TY - CHAP A1 - Müller, Klaus A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter T1 - Low-cost-Plot-Technologie fur die Mikrostrukturierung von Gassensoren T2 - Sensoren im Fokus neuer Anwendungen, 5. Dresdner Sensor-Symposium, 10. - 12. Dezember 2001, Dresden N2 - Bei der Herstellung von Mikrosensoren ist die Strukturierung von Elektroden oder elektrischen Zu-leitungen mit einem hohen Miniaturisierungsgrad ein entscheidender Punkt. Dazu müs-sen häufig teure Verfahren (Lithographie, Maskentechniken) herangezogen werden.Dieser Beitrag beschreibt eine low-cost-Technologie zur Herstellung organischer Mikrostrukturen für elektronische und messtechnische Anwendungen im Bereich der Sensorik. Geplottete Strukturen mit Polypyrrol und Poly(3,4-Ethylen-Dioxy-Thiophen), dotiert mit Polystyrolsulfonat (PEDOT/PSS) wurden als Widerstandssensoren für die Detektion von Luftfeuchte ein-gesetzt. Die prinzipielle Ein-satzmöglichkeit unserer Technik im Bereich der organischen Elektronik konnten wir mit dem Bau organischer Feldeffekttransistoren nachweisen. Mit einem computergesteu-erten Plotter des Typs Rol-land DXY-1150A, Plot-Kapillaren für das Tuschezeichnen, handelsüblichen Folien für wasserlösliche Tinten als Substrat und kolloidalen Graphit als leitendes Material konnten wir Auflösungen, das heißt insbesondere Kanalbreiten bzw. Elektrodenabstände im Bereich von 20+10%B5m (auf 2cm Länge) her-stellen. Y1 - 2002 SN - 3-935712-71-5 SP - 166 EP - 169 PB - w.e.b. Universitätsverlag CY - Dresden ER - TY - CHAP A1 - Batchelor, David R. A1 - Berg, A. A1 - Simon, Sylvio A1 - Wagner, Lothar A1 - Viehweger, Bernd A1 - Schmeißer, Dieter T1 - Development of Joining Techniques through Pressforming of Steel and Aluminium Y1 - 2001 UR - http://www.materialsweek.org/proceedings/index.htm ER - TY - CHAP A1 - Henkel, Karsten A1 - Elling, B. A1 - Danz, R. A1 - Büchtemann, A. A1 - Straube, Oliver A1 - Paloumpa, Ioanna A1 - Yfantis, Alexandros D. A1 - Schmeißer, Dieter T1 - Piezoelectric polymer sensor for high pressures in forming machines Y1 - 2001 UR - http://www.materialsweek.org/proceedings/index.htm ER - TY - CHAP A1 - Hulea, Iulian A1 - Hoffmann, Patrick A1 - Brinza, Monica A1 - Batchelor, David R. A1 - Schmeißer, Dieter T1 - The interface of friction-welded Al-Fe joints. ATB Metallurgy Y1 - 2001 ER - TY - CHAP A1 - Jaegermann, Wolfram A1 - Schmeißer, Dieter T1 - Elementary Processes at Solid/Electrolyte Interfaces Y1 - 2001 ER - TY - CHAP A1 - Yfantis, Alexandros D. A1 - Tsiniarakis, G. A1 - Labrakopoulos, S. A1 - Yfantis, Alexandros D. A1 - Schmeißer, Dieter T1 - Conductive polymers of pyrrole as pigments in organic anticorrosive coatings-application for aluminium alloys Y1 - 2001 ER - TY - CHAP A1 - Sidorenko, Alexander A1 - Tokarev, Igor A1 - Krenek, Radim A1 - Burkov, Yevgen A1 - Schmeißer, Dieter A1 - Minko, S. A1 - Stamm, Manfred ED - Champion, Yannick ED - Fecht, Hans-Jörg T1 - Generation of Nanostructured Materials from Thin Films of Block Copolymer Assembles T2 - Nano-architectured and manostructured materials, fabrication, control and properties, EUROMAT 2003 Y1 - 2004 SN - 3-527-31008-8 SP - 143 EP - 150 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Schmeißer, Dieter A1 - Müssig, Hans-Joachim T1 - Pr-silicate formation on SiO2 covered 3C-SiC(111) T2 - Physics of semiconductors, 27th International Conference on the Physics of Semiconductors Y1 - 2005 SN - 0-7354-0257-4 SP - 75 EP - 76 PB - AIP, American Inst. of Physics CY - New York, NY ER - TY - CHAP A1 - Schmeißer, Dieter T1 - Chemical Bonding in Low-k Dielectric Materials for Interconnect Isolation: Characterization using XAS and EELS KW - XAS KW - EELS KW - low-k Materials Y1 - 2006 ER - TY - CHAP A1 - Hoffmann, Patrick A1 - Schmeißer, Dieter A1 - Engelmann, Hans-Jürgen A1 - Zschech, Ehrenfried A1 - Stegmann, Heiko A1 - Himpsel, Franz J. A1 - Denlinger, Jonathan D. ED - Tsui, Ting Y. T1 - Characterization of chemical bonding in low-k dielectric materials for interconnect isolation: A XAS and EELS Study T2 - Materials, technology and reliability of low-k dielectrics and copper interconnects, symposium held April 18 - 21, 2006, San Francisco, California Y1 - 2006 SN - 978-1-55899-870-5 SP - 55 EP - 62 PB - Materials Research Society CY - Warrendale, Pa. ER - TY - CHAP A1 - Schmeißer, Dieter A1 - Zheng, Fan A1 - Perez-Dieste, Virginia T1 - Silicate Formation at the Interface of Pr-Oxide as a High-K Dielectric and Si(001) surfaces Y1 - 2006 ER - TY - CHAP A1 - Domaradzki, Jarosław A1 - Schmeißer, Dieter A1 - Kaczmarek, Danuta A1 - Beuckert, Guido A1 - Prociow, E. L. A1 - Borkowska, Angnieszka A1 - Kudrawiec, Robert A1 - Misiewicz, J. T1 - Characterization of Nanocrystalline TiO2 - HfO2 Thin Films Prepared by Low Pressure Hot Target Reactive Magnetron Sputtering Y1 - 2006 ER - TY - CHAP A1 - Schmeißer, Dieter A1 - Zheng, Fan A1 - Himpsel, Franz J. A1 - Engelmann, Hans-Jürgen A1 - Zschech, Ehrenfried T1 - Silicate Formation at the Interface of High-k Dielectrics and Si(001) Surfaces Y1 - 2006 ER - TY - CHAP A1 - Zschech, Ehrenfried A1 - Stegmann, Heiko A1 - Schmeißer, Dieter A1 - Hoffmann, Patrick T1 - Chemical Bonding, Permittivity, and Elastic Properties in Locally Modified Organosilicate Glass Y1 - 2006 ER - TY - CHAP A1 - Tallarida, Massimo A1 - Schmeißer, Dieter A1 - Zheng, Fan T1 - X-ray Absorption and Photoemission Spectroscopy of 3C- and 4H-SiC Y1 - 2006 ER - TY - CHAP A1 - Tallarida, Massimo A1 - Sohal, Rakesh A1 - Schmeißer, Dieter T1 - Resonant photoemission at the oxygen K edge as a tool to study the electronic properties of defects at SiO2/Si and SiO2/SiC interfaces Y1 - 2006 ER - TY - CHAP A1 - Sohal, Rakesh A1 - Torche, Mohamed A1 - Schmeißer, Dieter T1 - Al-Oxynitrides as a Buffer Layer for Pr2O3/SiC Interfaces Y1 - 2006 ER - TY - CHAP A1 - Schmeißer, Dieter A1 - Wehner, Stefan A1 - Hoffmann, Patrick A1 - Brand, Helmut R. A1 - Küppers, Jürgen ED - Descalzi, Orazio T1 - Influence of the Substrate on the Pattern Formation of a Surface Reaction T2 - Nonequilibrium statistical mechanics and nonlinear physics, XV Conference on Nonequilibrium Statistical Mechanics and Nonlinear Physics, Mar del Plata, Argentina, 4 - 8 December 2006 Y1 - 2007 SN - 978-0-7354-0421-2 SP - 121 EP - 126 PB - AIP Publishing CY - Melville, New York ER - TY - CHAP A1 - Müller, Sebastian A1 - Schmeißer, Dieter T1 - Synchrotron radiation spectroscopy studies of ultrathin chromium films on titanium dioxide T2 - International Students and Young Scientists Workshop "Photonics and Microsystems", 2009, 25 - 27 June 2009, Harz University, Wernigerode, Germany KW - synchrotron KW - radiation KW - spectroscopy KW - ultrathin KW - titanium KW - chromium Y1 - 2009 SN - 978-1-4244-4303-1 SP - 64 EP - 68 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Kolanek, Krzysztof A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Schmeißer, Dieter T1 - In situ measurements of the atomic layer deposition of high-k dielectrics by atomic force microscope for advanced microsystems T2 - International Students and Young Scientists Workshop "Photonics and Microsystems", 2009, 25 - 27 June 2009, Harz University, Wernigerode, Germany KW - atomic layer deposition KW - microsystems KW - high-k dielectrics Y1 - 2009 SN - 978-1-4244-4303-1 SP - 47 EP - 51 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Klocek, Jolanta A1 - Friedrich, Daniel A1 - Schmeißer, Dieter A1 - Hecker, Michael A1 - Zschech, Ehrenfried T1 - The stability of C60 and its derivatives upon handling in microsystems technologies T2 - International Students and Young Scientists Workshop "Photonics and Microsystems", 2009, 25 - 27 June 2009, Harz University, Wernigerode, Germany KW - c60 KW - derivatices Y1 - 2009 SN - 978-1-4244-4303-1 SP - 43 EP - 46 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Kolanek, Krzysztof A1 - Schmeißer, Dieter T1 - Nobel "in-situ2" Approach to Modified ALD Processes for Nano-functional Metals Oxide Films KW - in-situ2 KW - ALD KW - nano-functional Y1 - 2009 ER - TY - CHAP A1 - Heim, S. A1 - Friedrich, Daniel A1 - Guttmann, P. A1 - Rehbein, S. A1 - Chumakov, Dmytro A1 - Ritz, Y. A1 - Schneider, G. A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried T1 - Dynamical X-ray Microscopy Study of Stress-Induced Voiding in Cu Interconnects KW - x-ray KW - Microscopy KW - Interconnects Y1 - 2009 UR - http://link.aip.org/link/?APCPCS/1143/20/1 ER - TY - CHAP A1 - Seifarth, Olaf A1 - Wilke, A. A1 - Walczyk, Christian A1 - Dabrowski, Jarek Marek A1 - Zaumseil, Peter A1 - Schmeißer, Dieter A1 - Müssig, Hans-Joachim A1 - Schroeder, Thomas T1 - Band gap and electronic structure determination with XAS and UPS of thin Pr-oxide films on Si(111) T2 - Proceedings of 15th Workshop on Dielectrics in Microelectronics, Bad Saarow, 23 - 25 June 2008, Bad Saarow (Berlin) KW - band gab KW - XAS KW - UPS KW - Si(111) Y1 - 2008 SP - 285 EP - 286 ER - TY - CHAP A1 - Henkel, Karsten A1 - Burkov, Yevgen A1 - Bergholz, Matthias A1 - Karavaev, Konstantin A1 - Sohal, Rakesh A1 - Torche, Mohamed A1 - Schmeißer, Dieter T1 - Al-Oxynitride as a buffer layer for high-k dielectrics T2 - Proceedings of 15th Workshop on Dielectrics in Microelectronics, Bad Saarow, 23 - 25 June 2008, Bad Saarow (Berlin) KW - buffer layer KW - high-k KW - dielectric Y1 - 2008 SP - 161 EP - 162 ER - TY - CHAP A1 - Henkel, Karsten A1 - Mandal, Dipankar A1 - Seime, Bernd A1 - Paloumpa, Ioanna A1 - Lazareva, I. A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Electrical investigations on MFIS structures consisting P[VDF/TrFE] as ferro-electric layer for non-volatile memory applications T2 - Proceedings of 15th Workshop on Dielectrics in Microelectronics, Bad Saarow, 23 - 25 June 2008, Bad Saarow (Berlin) KW - MFIS, P[VDF/TrFE] KW - ferroelectric KW - non-volatile Y1 - 2008 SP - 159 EP - 160 ER - TY - CHAP A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried T1 - HfO2 ALD-growth studied by in situ photoemission T2 - Proceedings of 15th Workshop on Dielectrics in Micoelectronics, Bad Saarow, 23 - 25 June 2008 KW - ald KW - photoemission Y1 - 2008 SP - 289 EP - 290 ER - TY - CHAP A1 - Wyrodek, Jakub A1 - Tallarida, Massimo A1 - Weisheit, Martin A1 - Schmeißer, Dieter T1 - Determination of interfacial layers in high-k nanomaterials by ADXPS measurements Y1 - 2010 ER - TY - CHAP A1 - Starzyk, Łukasz A1 - Tallarida, Massimo A1 - Schmeißer, Dieter T1 - Band alignment of high-k/SiO2/Si stacks incorporating Zr and Al oxides prepared by atomic layer deposition Y1 - 2010 ER - TY - CHAP A1 - Broczkowska, K. A1 - Klocek, Jolanta A1 - Friedrich, Daniel A1 - Henkel, Karsten A1 - Kolanek, Krzysztof A1 - Urbanowicz, A. A1 - Schmeißer, Dieter A1 - Miller, M. A1 - Zschech, Ehrenfried T1 - Fullerene based materials for ultra-low-k application T2 - International Students and Young Scientists Workshop "Photonics and Microsystems", Szklarska, Poreba, Poland, 25 - 27 June 2010 Y1 - 2010 SN - 978-1-4244-8324-2 SP - 39 EP - 43 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Karavaev, Konstantin A1 - Tallarida, Massimo A1 - Schmeißer, Dieter ED - Vierhaus, Heinrich Theodor T1 - In-situ Atomic Layer Deposition growth of Hafnium oxide T2 - DEDIS-Nano-Days, October 11th and October 12th, 2007 Y1 - 2007 SP - 13 EP - 19 PB - BTU CY - Cottbus ER - TY - CHAP A1 - Henkel, Karsten A1 - Torche, Mohamed A1 - Sohal, Rakesh A1 - Schwiertz, Carola A1 - Hoffmann, Patrick A1 - Schmeißer, Dieter ED - Dudley, Michael T1 - Pr-O-N Dielectrics for MIS Stacks on Silicon and Silicon Carbide Surfaces T2 - Silicon carbide 2006 - materials, processing and devices, symposium held April 18 - 20, 2006, San Francisco, California, U.S.A. Y1 - 2006 SN - 978-1-55899-867-4 SP - 353 EP - 358 PB - Materials Research Society CY - Warrendale, Pa. ER - TY - CHAP A1 - Müller, Klaus A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter T1 - Carbon-Plot-Micostructuring for All-Polymer-Transistors Y1 - 2001 ER - TY - CHAP A1 - Yfantis, Alexandros D. A1 - Bourdas, N. A1 - Lambrakopoulos, S. A1 - Yfantis, N. A1 - Paloumpa, Ioanna A1 - Yfantis, Alexandros D. T1 - Conductive polymers precoats-application on metallisation of ABS Y1 - 2003 ER - TY - CHAP A1 - Yfantis, Alexandros D. A1 - Bourdas, N. A1 - Lambrakopoulos, S. A1 - Yfantis, N. A1 - Paloumpa, Ioanna A1 - Yfantis, Alexandros D. T1 - Primers of conductive polymers-application in powder coatings technology Y1 - 2003 ER - TY - CHAP A1 - Yfantis, Alexandros D. A1 - Bourdas, N. A1 - Yfantis, N. A1 - Yfantis, Alexandros D. A1 - Lambrakopoulos, S. A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter T1 - A study of anticorrosive conversion coatings based on conductive polymers of pyrrole Y1 - 2002 ER - TY - CHAP A1 - Hoffmann, Patrick A1 - Mikalo, Ricardo Pablo A1 - Batchelor, David R. A1 - Beuckert, Guido A1 - Schmeißer, Dieter A1 - Kittler, Martin A1 - Ourmazd, A. A1 - Lewerenz, Hans-Joachim T1 - Solare Energieumwandlung in dünnen Schichten Y1 - 2000 ER - TY - CHAP A1 - Hoffmann, Patrick A1 - Batchelor, David R. A1 - Schmeißer, Dieter T1 - Spectro-Microscopic analyses in metallurgical systems: spheroidic graphite in cast iron and the interface of friction-welded Al-Fe joints Y1 - 2000 ER - TY - CHAP A1 - Gehrlich, Lukas A1 - Ohsiek, Susanne A1 - Klein, C. A1 - Geiß, M. A1 - Friedemann, Michael A1 - Kücher, Peter A1 - Schmeißer, Dieter T1 - Ultrathin TaN/Ta barrier modifications to fullfill next technology node requirements T2 - 2011 IEEE International Interconnect Technology Conference and 2011 Materials for Advanced Metallization (IITC/MAM 2011), Dresden, Germany, 8 - 12 May 2011 Y1 - 2011 SN - 978-1-4577-0503-8 U6 - https://doi.org/10.1109/IITC.2011.5940322 SP - 82 EP - 84 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Mandal, Dipankar A1 - Henkel, Karsten A1 - Schmeißer, Dieter T1 - Control of the Crystalline Polymorph, Molecular Dipole and Chain Orientations in P(VDF-HFP) for High Electrical Energy Storage Application T2 - International Conference on Nanoscience, Technology and Societal Implications (NSTSI), 2011 Y1 - 2012 SN - 978-1-4577-2035-2 U6 - https://doi.org/10.1109/NSTSI.2011.6111801 PB - IEEE ER - TY - CHAP A1 - Richter, Matthias A1 - Schmeißer, Dieter T1 - The Co2p oxidation state in Co-PI catalysts T2 - Meeting Abstracts-Electrochemical Society, Pacific Rim Meeting on Electrochemical and Solid-State Science, Honolulu, 2012 Y1 - 2012 N1 - MA2012-02(14) SP - 1803 PB - The Electrochemical Society ER - TY - CHAP A1 - Richter, Matthias A1 - Friedrich, Daniel A1 - Schmeißer, Dieter T1 - Multiple Auger decay at resonant photo-excitation in carbon thin films T2 - Meeting Abstracts-Electrochemical Society, Pacific Rim Meeting on Electrochemical and Solid-State Science, Honolulu, 2012 Y1 - 2012 UR - http://ma.ecsdl.org/content/MA2012-02/50/3509.full.pdf+html N1 - MA2012-02(50) SP - 3509 PB - The Electrochemical Society ER - TY - CHAP A1 - Schmeißer, Dieter A1 - Richter, Matthias A1 - Tallarida, Massimo ED - Heber, Jörg ED - Schlom, Darrell ED - Tokura, Yoshinori ED - Waser, Rainer ED - Wuttig, Matthias T1 - Intrinsic defects in TiO2 to explain resistive switching devices T2 - Frontiers in Electronic Materials: A Collection of Extended Abstracts of the Nature Conference Frontiers in Electronic Materials, June 17 to 20 2012, Aachen, Germany KW - resonant photoelectron spectroscopy KW - Auger processes KW - XPS KW - X-ray absorption spectroscopy Y1 - 2012 SN - 978-3-527-41191-7 U6 - https://doi.org/10.1002/9783527667703.ch45 SP - 255 EP - 256 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Mandal, Dipankar A1 - Henkel, Karsten A1 - Das, Suken A1 - Schmeißer, Dieter ED - Heber, Jörg ED - Schlom, Darrell ED - Tokura, Yoshinori ED - Waser, Rainer ED - Wuttig, Matthias T1 - Control of β- and γ-Phase formation in electroactive P(VDF-HFP) films by silver nano-particle doping T2 - Frontiers in Electronic Materials: A Collection of Extended Abstracts of the Nature Conference Frontiers in Electronic Materials, June 17 to 20 2012, Aachen, Germany KW - P(VDF.HFP) KW - electroactive phase KW - nanoparticle doping KW - FTIR Y1 - 2012 SN - 978-3-527-41191-7 U6 - https://doi.org/10.1002/9783527667703.ch69 SP - 640 EP - 641 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Tallarida, Massimo T1 - III-V/oxide interfaces investigated with synchrotron radiation photoemission spectroscopy T2 - Meeting Abstracts-Electrochemical Society, Pacific Rim Meeting on Electrochemical and Solid-State Science, Honolulu, 2012 KW - interfaces KW - III/V KW - Synchrotron Photoemission Spectroscopy Y1 - 2012 UR - http://ma.ecsdl.org/content/MA2012-02/31/2587.full.pdf+html N1 - MA2012-02(31) SP - 2587 EP - 2587 PB - The Electrochemical Society ER - TY - CHAP A1 - Mai, Andreas A1 - Dauderstädt, Ulrike A1 - Pahner, D. A1 - Krellmann, M. A1 - Schmeißer, Dieter A1 - Wagner, M. T1 - In situ determination of laser induced degradation of micro-mirror arrays T2 - International Students and Young Scientists Workshop Photonics and Microsystems, Cottbus, Germany, 8 - 10 June 2011 N2 - The Fraunhofer Institute for Photonic Microsystems (Fraunhofer IPMS) develops spatial light modulators (SLMs) based on arrays of tiltable micro mirrors on a semiconductor chip. Typical applications are pattern generation for deepUV-laser mask writing or structured illumination in microscopy. Development and optimization of such SLMs requires detailed knowledge of the device behaviour under operating conditions. Here, the flatness of each single mirror effects the image resolution and contrast of the generated pattern and is amongst others a characteristic property of SLMs. In this context a surface topography measurement under laser exposure (in situ) was designed. The interferometric setup uses the phase-shift principle and allows a resolution in z-direction in the single-digit nanometer range. During irradiation with UV-laser light at 248 nm (KrF) and energy densities of up to 20 mJ/cm2 the change in single micro-mirrors topography was detected in situ. Measurementswith varying pulse energies were carried out to identify an impacton the device performance. In general, the setup is neither limited to a specific illumination wavelength nor to micro-mirrors as structures under test. KW - micro-mirror arrays KW - laser induced degradation Y1 - 2011 SN - 978-1-4577-1651-5 U6 - https://doi.org/10.1109/STYSW.2011.6155850 SP - 84 EP - 88 PB - IEEE CY - Piscataway, NJ ER - TY - CHAP A1 - Cuypers, Daniel A1 - Dorp, Dennis H. von A1 - Tallarida, Massimo A1 - Brizzi, Simone A1 - Rodriguez, Leonard A1 - Conard, Thierry A1 - Arnauts, Sophia A1 - Schmeißer, Dieter A1 - Adelmann, Christoph A1 - De Gendt, Stefan T1 - Study of InP Surfaces After Wet Chemical Treatments T2 - Meeting Abstracts-Electrochemical Society, San Francisco, 2013 KW - Synchrotron Radiation Photoelectron Spectroscopy KW - InP KW - Wet chemical treatment Y1 - 2013 UR - http://ma.ecsdl.org/content/MA2013-02/30/2132.full.pdf+html N1 - MA2013-02(30) SP - S. 2132 PB - The Electrochemical Society ER - TY - CHAP A1 - Henkel, Karsten A1 - Tallarida, Massimo A1 - Haeberle, Jörg A1 - Gargouri, Hassan A1 - Naumann, Franziska A1 - Gruska, Bernd A1 - Arens, Michael A1 - Schmeißer, Dieter ED - Glück, Bernhard K. ED - Schmidt, Sindy ED - Stein, Erhard ED - Raschke, Jörg-Uwe ED - Richter, Hans T1 - PE-ALD-Al2O3-Schichten für die Passivierung von Solarzellen T2 - Tagungsband Photovoltaik-Meeting: Anwendungen-Qualität-Perspektiven, Senftenberg, 16.04.2014 N2 - Dünne Al2O3-Schichten wurden bei Substrattemperaturen zwischen Raumtemperatur und 200°C mittels PE-ALD auf Si-Substraten abgeschieden und ellipsometrisch, spektroskopisch und elektrisch charakterisiert. Ihr Potenzial für die chemische und Feldeffektpassivierung der Oberflächenrekombination wird bewertet. KW - Al2O3 KW - Atomlagenabscheidung (ALD) KW - Passivierung KW - PE-ALD KW - negative fixe Oxidladungen Y1 - 2014 SP - 7 EP - 14 PB - Cottbus-Senftenberg CY - BTU ER - TY - CHAP A1 - Krenek, Radim A1 - Cimrova, Vera A1 - Seifarth, Olaf A1 - Bocharova, Vera A1 - Gorodyska, Ganna A1 - Sidorenko, Alexander A1 - Schmeißer, Dieter A1 - Stamm, Manfred T1 - Electronic Properties of Metals Embedded into Porous Polymeric Nanotemplates T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 41 N2 - We report on electrical measurements (current-voltage characteristics (CVC)) of metals which are templated via porous polymeric nanotemplates. The nanotemplates are based on self-organization of poly(styrene-block 4-vinylpyridine) (PS-PVP). The cylindrical pores of 8 nm in the diameter are ordered in a hexagonal lattice (24 nm in the period). Chromium and gold were embedded in the nanotemplates by magnetron sputtering, nickel was electrodeposited. These thin films were characterized by AFM, ellipsometry, x-ray reflectivity, XAS, XPS and NEXAFS. CVC were acquired by a connection common for light emitting diodes discussing a further use of nanotemplated metals in these devices. To make the connection, the nanotemplate was deposited on glass with ITO electrodes, then metal was embedded into it and finally Al electrodes were evaporated on the device. Behaviour of space charge limited currents (SCLC) was observed. Also, we deal with the electrical mode of AFM as well. Finally electronic behaviour of the metallic nanorods embedded in polymeric nanotemplates is discussed in respective to the structure and chemical composition obtained by AFM and x-ray techniques. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/cpp/session/25/contribution/2 SN - 0420-0195 SP - S. 108 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Tallarida, Massimo A1 - Sohal, Rakesh A1 - Schmeißer, Dieter T1 - Electronic properties of the 2x1 3C-SiC surface reconstruction studied with resonant photoemission T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 41 N2 - We have studied the 2x1 reconstructed surface of the 3C-SiC polytype by means of photoemission spectroscopy. The reconstruction was characterized through Si2p and C1s core level and angle-integrated valence band spectroscopy, and confirmed by the observation of a two-domain 2x1 LEED pattern. The electronic properties of this surface were investigated by collecting valence band spectra at photon energies near the Si2p and C1s absorption edges. The results show a strong dependence of the photoemission intensity on the excitation energy with characteristic resonances for certain valence band features. With a detailed study of the resonances we are able to assign the electronic origin of the resonating states and the nature of the electronic transition near the absorption edges. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/hl/session/5/contribution/2 SN - 0420-0195 SP - S. 239 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Wehner, Stefan A1 - Hofmann, Patrick A1 - Schmeißer, Dieter A1 - Brand, Helmut R. A1 - Küppers, Jürgen T1 - Pattern formation in the CO + O reaction on Ir(111) surfaces under the influence of noise T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 41 N2 - The rate of CO oxidation on Ir(111) surfaces exhibits bistability at T = 500 K in a range of the CO fraction Y in the CO + O reactant gas flux. Quadrupol mass spectrometer measurements of the CO2 rates as a function of the noise strength imposed on Y are well reproduced by parameter-free modeling. We present Photoelectron emission microscopy (PEEM) measurements and 2D calculations of the spatio-temporal patterns of CO and O rich domains. The role of combined multiplicative and additive noise on Y for CO and O domain wall motion and island nucleation-growth-coalescence processes is analysed. For small noise amplitudes few islands nucleate and grow up to some 100 µ m in diameter, before they merge with another island. With increasing noise amplitudes more islands nucleate. With large noise amplitudes bursts to and switching between the branches is observed. The domain wall velocity is found to be independent of the noise strength and island size. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/syss/session/1/contribution/9 SN - 0420-0195 SP - S. 708 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Wehner, Stefan A1 - Hoffmann, Patrick A1 - Schmeißer, Dieter A1 - Brand, Helmut R. A1 - Küppers, Jürgen T1 - CO oxidation on Ir(111) surfaces: consequences of anisotropic diffusion and noise T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 41 N2 - The CO oxidation reaction on Iridium(111) surfaces shows bistability in a limited range of the CO fraction of the reactant gas flux Y and a wide range of temperatures T. The two branches are characterized by their reactivity for CO2 formation. The upper rate (high CO2 formation) rate is related to high oxygen coverage on the surface, the lower rate (little CO2 formation) to high CO coverage. Quadrupol mass spectroscopy and PEEM (photoelectron emission microscopy) was employed to study the influence of a noisy reactant gas flux composition on the spatio-temporal pattern development in the CO oxidation reaction on flat Ir(111) and stepped Ir(977) surfaces. PEEM shows nucleation and growth of few oxygen resp. CO islands at small noise amplitudes. Anisotropic diffusion of CO parallel and normal to the steps causes elliptic shapes of large islands. The long axes of the ellipses are aligned along the steps. At increased noise amplitudes the density of islands becomes larger. 2D modeling of the phenomena based on reaction-diffusion differential equations reproduces the experimental findings quite nicely. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/o/session/14/contribution/37 SN - 0420-0195 SP - S. 475 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Seime, Bernd A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Buffer layer investigation of MFIS stacks with an organic ferroelectric layer T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 42 N2 - Ferroelectric field effect transistors are considered as future non volatile and non destructive readout memory cells. Conventional Perowskite-type ferroelectric materials are shown to work but they need expensive high temperature and high partial pressure processing steps inducing also unintentional and undefined interfacial layers.A possible low cost solution is the use of poly[vinylidene fluoride trifluoroethylene (P[VDF/TrFE]). This is a ferroelectric polymer which can be spin coated at room temperature onto silicon suited with well defined buffer layers. Using P[VDF/TrFE] we focus on metal ferroelectric insulator semi-conductor (MFIS) structures. In MFIS structure a part of the programming voltage drops over the buffering insulator. We report on attempts to minimize this fraction by optimizing the voltage divider over the buffer and the ferroelectric layers. CV measurements for different thickness of the buffer (10-235nm) and the ferroelectric layer(100nm-1μm) and for different permittivity values of the buffer layer(SiO2, Al2O3, HfO2) will be presented. This work is supported by Deutsche Forschungsgemeinschaft within priority program 1157 (DSCH 745/11-1). Y1 - 2007 UR - http://www.dpg-verhandlungen.de/year/2007/conference/regensburg/part/df/session/11/contribution/1 SN - 0420-0195 SP - S. 216 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Mandal, Dipankar A1 - Müller, Klaus A1 - Seifarth, Olaf A1 - Hoffman, Patrick A1 - Henkel, Karsten A1 - Schmeißer, Dieter T1 - Study of reactions at the interface P(VDF/TrFE)/Al and P(VDF/TrFE)/PEDOT:PSS T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 42 N2 - Due to potential use in non volatile memory application, Poly(vinylidene fluoride/trifluoroethylene) (P(VDF-TrFE)) is a great deal of interest, especially to produce organic field effect transistors (OFET). Right now it was found that Aluminum is one of the cost-effective inorganic electrode candidate. On the other hand, poly(3,4 ethylenedioxythiophene):poly(4-styrenesulfonate)(PEDOT:PSS) shows promising behavior for the application as organic electrode. In part of our investigations we have systematically studied surface interactions of organic ferroelectric thin films (P(VDF-TrFE))with inorganic (Al) and organic layers (PEDOT:PSS). By X-ray photoelectron spectroscopy (XPS) is has been found that there is a interfacial reaction with Al and the copolymer. In contrast, for electrodes, made of PEDOT: PSS, we found not such kind of behavior. In this case, we found no evidence for any surface reaction. Furthermore, we present our results concerning the orientation of permanent dipoles in the co-polymer (formed between hydrogen and fluorine atom). Here, we use Near-edge X-ray absorption fine structure (NEXAFS) analysis at the U 49/2 - PGM2 beam line of the BESSY-II Synchrotron. This work is supported by Deutsche Forschungsgemeinschaft (DFG) within priority program 1157 (DSCH 745/11-1). Y1 - 2007 UR - http://www.dpg-verhandlungen.de/year/2007/conference/regensburg/part/syoe/session/8/contribution/18 SN - 0420-0195 SP - S. 797 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Henkel, Karsten A1 - Sohal, Rakesh A1 - Torche, Mohamed A1 - Schwiertz, Carola A1 - Burkov, Yevgen A1 - Schmeißer, Dieter T1 - PrOx/AlON stacks as a high-k candidate on SiC T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 42 N2 - We study the chemical stability and electrical properties of Pr-oxides-SiC MIS stacks. In MISFET devices for high power applications the electric field scaling at the interface between semiconductor and insulator is determined by the ratio of their permittivity values. A high-k material can be used to optimize the performance of such devices. In previous studies we had to understand that the chemical reactivity of the PrOx/SiC interface causes a destructive interaction yielding silicate and graphite formation as well as poor electrical performance after direct deposition of PrOx onto SiC. Therefore we introduced an additional chemically inert layer and in this contribution we focus on PrOx/AlON as a suitable insulator stack. In our spectroscopic investigations we recognized a stable AlON/3C-SiC interface even for annealing steps up to 900∘C. First electrical characterizations are performed on Si substrates and we find a strong improvement in the leakage current by several orders of magnitude down to values of 10−7 A/cm2 at an EOT of 4nm and interface state densities of mean values of 5*1011/eVcm2. We also report on our ongoing electrical characterization of such stacks on SiC substrates. This work is supported by Deutsche Forschungsgemeinschaft within priority program 1157 (DSCH 745/9-2). Y1 - 2007 UR - http://www.dpg-verhandlungen.de/year/2007/conference/regensburg/part/df/session/10/contribution/8 SN - 0420-0195 SP - S. 215 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Sebastian A1 - Schmeißer, Dieter T1 - The initial stages of Chromium growth on Titaniumdioxide-Investigations using synchrotron radiation T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 42 N2 - We investigate the interface of Cr-TiO2 during the initial stages of Cr deposition. Experiments are carried out at BESSY II (BL U49/2-PGM2). Using XPS, XAS and ResPES we obtain information about electronic structure at the interface. We confirm the results of growth studies by Christian Winde obtained by TEM-EELS. In addition, we find that Cr deposition induces two gap states which appear about 1 eV and 3 eV below EF. Using ResPES, these states can be identified as being Cr-like and Ti-like respectively. Core-level-XPS and CIS-spectra of the lower gap state indicate the existence of mainly Cr4+ at low coverage (< 1 ML). At higher coverage (≈ 2.5 ML) metallic Cr is observed as well as metallic Ti. Oxidized Cr occurs mainly as Cr3+. CIS-spectra of higher gap state show metallic behavior with both Cr- and Ti-like character. CIS-spectra of lower gap-state confirm the existence of Cr3+. Reference: Christian Winde, Herstellung und Charakterisierung von Cr Schichten auf TiO2 (110)Oberflächen, PhD Thesis, University of Stuttgart, 2002 Y1 - 2007 UR - http://www.dpg-verhandlungen.de/year/2007/conference/regensburg/part/o/session/33/contribution/8 SN - 0420-0195 SP - S. 598 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Nielsen, Karl-Wilhelm A1 - Bauer, Sebastian A1 - Senn, Konrad A1 - Goennenwein, Sebastian T. B. A1 - Opel, Matthias A1 - Cezar, Julio C. A1 - Schmeißer, Dieter A1 - Gross, Rudolf T1 - X-ray magnetic circulardichroism in cobalt-doped ZnO T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 42 N2 - Cobalt-doped ZnO is a diluted magnetic semiconductor with a reported Curie-temperature well above 300 K. Nevertheless, the origin of the ferromagnetic exchange still is under debate. To clearify this issue we have investigated cobalt-doped ZnO thin films with x-ray magnetic circular dichroism (XMCD). The (0001)-oriented Zn0.95Co0.05O thin films were grown on (0001) ZnO, (0001) Al2O3, and (0001) ScAlMgO4 substrates by pulsed laser deposition. The magnetic properties were measured by SQUID magnetometry and XMCD. Room temperature magnetization measurements by SQUID magnetometry and XMCD in the fluorescence yield mode reveal ferromagnetic behavior with similar shape of the magnetization curves, however, with different absolute values. XMCD magnetization in total electron yield, which is surface sensitive, show only small magnetic moments, most likely due to a magnetically dead surface layer. This work is supported by the DFG via SPP1157. Y1 - 2007 UR - http://www.dpg-verhandlungen.de/year/2007/conference/regensburg/part/ma/session/15/contribution/13 SN - 0420-0195 SP - S. 454 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Kachel, Krzysztof A1 - Richter, Matthias A1 - Philip, Shine A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Performance of organic solar cells with a ferroelectric component T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Charge dissociation and recombination are important factors for the efficiency of organic solar cells, even in blended systems of different polymers. As a new approach, the influence of additional blended ferroelectric nanoparticles on the solar cell performance is investigated. The ferroelectric dipole of the nanoparticle causes a local field, which could lead to a longer recombination time of the polaron pairs. As solar cell system we use bulk heterojunction cells or bilayer structures based on regioregular poly(3-hexylthiophene) (P3HT) as the donor and phenyl-C61-butyric acid methyl ester (PCBM) as the acceptor molecule. As ferroelectric additive we use the ferroelectric copolymer poly(vinylidene fluoride trifluoroethylene) (P(VDF-TrFE)) or BaTiO3. The copolymer is spincoated as ultrathin film of 20nm, whereas the BaTiO3 is incorporated as nanodispersion into the donor-acceptor blend. We present the solar cell parameters for the different geometries and ferroelectric materials as a function of ferroelectric content and of the alignment of the ferroelectric dipoles after application of an external electric field. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/cpp/session/27/contribution/6 SN - 0420-0195 SP - S. 153 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Klocek, Jolanta A1 - Friedrich, Daniel A1 - Zagorodniy, Kostyantyn A1 - Schmeißer, Dieter T1 - Spectroscopic investigations of interaction between C60 fullerene and nitrogen atom from amine group T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - We investigated interactions between fullerene molecule and amine group from 3-aminopropyl-trimethoxysilane (3AT). Theoretical calculations show that the material obtained as a result of interactions between 3AT and C60 fullerene may have extremely low dielectric constant around 1.6, so it could be considered as a candidate for ultra low-k (ULK) material applications. We prepared films composed of 3AT and fullerene by using two preparation techniques: spin-coating and evaporation. Interactions between these two components were investigated by using X- ray photoelectron spectroscopy (XPS) and Near Edge X-ray Absorption Fine Structure Spectroscopy (NEXAFS). We found that there are strong chemical reactions between the nucleophilic nitrogen atom from 3AT and electrophilic fullerene molecule. Results of NEXAFS measurements suggest that due to direct interactions between 3AT and C60 the shape of fullerene molecule is changed. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/23/contribution/1 SN - 0420-0195 SP - S. 231 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Kolanek, Krzysztof A1 - Karavaev, Konstantin A1 - Tallarida, Massimo A1 - Schmeißer, Dieter T1 - Atomic layer deposition of HfO2 onto SiO2 substrates investigated in-situ by non-contact UHV/AFM T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - We investigated in-situ the atomic layer deposition (ALD) of HfO2 onto SiO2 substrates with ultra high vacuum (UHV) non-contact atomic force microscope (NC-AFM). The ALD process was started after detailed analysis of the initial Si(001)/SiO2 substrate. The ALD cycles, made by using tetrakis-di-methyl-amido-Hf (TDMAHf) and water as precursors, were performed on the SiO2 substrate maintained at 230 ∘C. We studied the relation between the film growth and the root mean square surface roughness, surface skewness, kurtosis, fractal dimension and correlation length. In the initial stages of the ALD process with our analysis of the surface height histograms we were capable of determination: HfO2 layer thickness, surface coverage and surface roughness of a substrate and deposited material. Observation of the surface height histograms evolution during deposition allowed us to verify conformal and effective ALD growth on SiO2 substrate. With this detailed analysis of the surface topography we confirmed the completion of the first HfO2 layer after four ALD cycles. Y1 - 2010 SN - 0420-0195 SP - S. 248 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Michling, Marcel A1 - Tallarida, Massimo A1 - Kolanek, Krzysztof A1 - Schmeißer, Dieter T1 - In-situ EELS and UPS measurements on HfO2 ALD layers T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - In this contribution we report on our in-situ cycle-by-cycle (up to 10 cycles) investigations of the HfO2 ALD process using the methods of EELS and UPS. We used TDMA-Hf as a precursor and p-type Si wafer with natural oxide as the substrate. The EELS measurements were done with a primary energy of 52,5 eV and the UPS measurements with He I (21,218 eV). The change in the onset of the loss function is readily observed. Already after two cycles the value approach to the bulk value of HfO2. Upon ALD growth there is a remarkable decrease in the intensity of states within the gap. They are rather smooth and saturate after 10 cycles. With UPS we follow the variation of the VB onset and changes in the secondary electron onset. We summarize our data in a band diagram not based on bulk values but on cycle dependent quantities. With these cycle-by-cycle experiments we study the initial growth of HfO2 especially in the very first cycles. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/24/contribution/5 SN - 0420-0195 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Sebastian A1 - Schmeißer, Dieter T1 - Synchrotron radiation spectroscopy studies of the initial interaction between cobalt and titanium dioxide T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Small metallic particles deposited on oxide surfaces can serve as heterogeneous catalysts, as for example TiO2 supported cobalt is a known Fischer-Tropsch-Catalyst. The goal of the presented studies is to investigate the interaction between cobalt and TiO2 in the initial step of growth by synchrotron radiation based spectroscopy. PES studies of TiO2 supported cobalt show a reduction of the oxide support, accompanied by an oxidation of the deposited material. The oxidation is not complete, but metallic cobalt is found already in the very first step of growth. Uniform decrease of both substrate PES lines indicate very weak interaction between overlayer and TiO2. An atomic multiplet calculation including charge transfer and crystal field effects is applied to simulate the experimental Co 2p XAS and XPS spectra of the oxidized component. The results allow the identification of the local coordination as well as the identification of the oxidation state of cobalt. Y1 - 2010 SN - 0420-0195 SP - S. 652 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Philip, Shine A1 - Richter, Matthias A1 - Friedrich, Daniel A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Spectroscopic investigations of P3HT/PCBM films for organic BHJ solar cells T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Investigations of the electronic structure and composition of regioregular poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) based films using Near Edge X-Ray Absorption Fine Structure (NEXAFS) are presented. The measurements were performed at the U49/2-PGM2 beam line of BESSY II, Berlin recording TEY (total electron yield) and TFY (total fluorescence yield) data. Samples prepared by spin coating a mixture of P3HT dissolved in chloroform and PCBM dissolved in chlorobenzene onto ITO (indium tin oxide) coated glass slides were analyzed. Upon measuring the pure P3HT and PCBM, all reported excitations were observed, whereas the blended system is a weighted superposition of the related peaks. Analyzing the data we calculate the composition of the mixture. We also show angular dependent NEXAFS measurements of the P3HT/PCBM blend in order to measure the orientation and distribution of the P3HT polymer. Additionally, we show a new approach for organic solar cell application. BaTiO3 nanoparticles were incorporated as nanodispersion into the donor-acceptor blend or the ferroelectric copolymer poly(vinylidene fluoride trifluoroethylene) (P(VDF-TrFE)) was spincoated as an ultrathin film below the blend. Y1 - 2010 SN - 0420-0195 SP - S. 153 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Richter, Matthias A1 - Friedrich, Daniel A1 - Philip, Shine A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Study of P3HT/PCBM based films by NEXAFS T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - In this contribution we report on investigations of the electronic structure and composition of regioregular poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) based films by using Near Edge X-Ray Absorption Fine Structure (NEXAFS). The measurements were done at the U49/2-PGM2 beam line of BESSY II, Berlin using TEY (total electron yield) and TFY (total fluorescence yield) detection. The samples were produced by spin casting a mixture of P3HT (dissolved in chloroform) and PCBM (dissolved in chlorobenzene) on ITO (indium tin oxide) coated glass slides. Measurements of pure P3HT and PCBM show all typical excitations, whereas the blended system is a weighted superposition of the related peaks. Analyzing these weighted superposition, we observe in the surface sensitive TEY data an accumulation of P3HT, whereas in the bulk sensitive TFY signal an as expected mixture is found. We also show angular dependent NEXAFS measurements of the P3HT/PCBM blend in order to measure the orientation and distribution of the P3HT polymer. Additionally, we will show a new approach for organic solar cell application by introducing ferroelectric nanoparticles into the mixture. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/df/session/7/contribution/4 SN - 0420-0195 SP - S. 194 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Schmidt, Stephan A1 - Schmeißer, Dieter T1 - Cobalt/nickel mixed oxides - cathode materials for Li-Ion-Batteries T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Replacing Co by large amounts of Ni is considered to reduce costs in Li-Ion-Batteries while maintaining their performance. We are interested in whether this replacement causes changes in the valence band (VB) and conduction band (CB) states or not. Samples were prepared as thin films from nitrate solutions on metal substrates and annealed in air and UHV. The Co to Ni ratio was varied from 50/50 over 40/60 and 30/70 up to 20/80. The results are compared to the pure Co-oxide. Experiments were carried out at the U49/2 beamline at BESSYII, Berlin. XPS of the TM2p states reveals the existence of charge transfer ground states and different oxidation states. NEXAS at the Co2p, Ni2p and O1s edges projects the density of unoccupied states while resonant PES at these edges provides the related partial density of states (pDOS) and thus can be used to distinguish between the different contributions of TM3d and O2p states in the valence band region. We find systematic variation of the VB structure, the valence band maximum and a shift at the O1s absorption edge while the TM2p XPS and absorption spectra do not seem to be affected by the mixing. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/o/session/45/contribution/6 SN - 0420-0195 SP - S. 596 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Starzyk, Łukasz A1 - Tallarida, Massimo A1 - Schmeißer, Dieter T1 - Electrically optimized high-κ metal gate MOSFET by specific modification of the band alignment T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - The electrical optimization of metal/oxide/semiconductor gate stacks by specific modification of the band alignment for advanced MOS technology incorporating high dielectric constant (κ) materials is explored. Because of requirements concerning continued scaling of MOSFET transistors, gate oxides and cobalt electrode have been grown successively on Si substrate respectively by means of atomic layer deposition (ALD) and evaporation. The thicknesses of high-κ films were around 2 nm. In case of work function engineering, interfaces’ chemistry plays a fundamental role. We applied synchrotron radiation based x-ray photoelectron spectroscopy (SR XPS) to characterize our samples, which allows step by step in situ investigations. Co 2p, Al 2p, Hf 4f, Si 2p and O 1s core levels spectra were measured and analyzed. From valence band (VB) spectra we determined Schottky barrier height and electronic bands offsets. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/23/contribution/3 SN - 0420-0195 SP - S. 231 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Wyrodek, Jakub A1 - Tallarida, Massimo A1 - Schmeißer, Dieter A1 - Weisheit, Martin T1 - Determination of interfacial layers in high - k ALD nanolaminate materials by ARXPS and SRXPS measurements T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - The interfacial layers of high dielectric constant (high - k) nanolaminate films are here explored. Problems concerning ALD nanolaminate layers deals mainly with lack of accurate methods to determine in depth profile of few nm thick stacks. Modified angle resolved XPS(ARXPS) and synchrotron radiation XPS(SRXPS) are proposed as methods suitable in layer profiling. Studied stacks containing ZrO/HfO or AlO/ZrO, were prepared on Si substrates by atomic layer deposition (ALD). Two sets of experiments were covered. First dealt with initial growth (up to 20 cycles, with thickness d < 2nm) of AlO/ZrO and included layer by layer insitu investigation by SRXPS. Second experiment refer to industrial grown ZrO/HfO films ( d ∼ 3nm ) processed with various parameters resulting in both, layer by layer and homogenous depositions. For those samples exsitu XPS, with angle dependent variation of probing depth, measurements were covered. By comparing obtained intensity ratios for different angles with computational developed stack model it was found that no simple layer by layer but some intermixing growth occurred including interaction with silicon substrate. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/24/contribution/6 SN - 0420-0195 SP - S. 232 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Bergholz, Matthias A1 - Schmeißer, Dieter T1 - Band gap determination of thin Praseodymiumoxide layers on Aluminiumoxynitride films T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - High-k dielectrics are important as never bevore in semiconductor industry. We investigate Pr2O3 as one representative of this group on Silicon and Silicon-Aluminium oxynitride substrates. In earlier work we observed the positive influence of this AlOxNy intermediate layer on the electrical properties of the Pr2O3 layer. Now we present in-situ EELS, XPS and UPS measurements of gradually grown thin Pr2O3 on AlOxNy. From these measurements we determine the band structure and find a very fast change of the band gap for the first few Ångström, coupled with n-type behaviour for the Pr2O3 film. These results are compared with RIXS measurements of a 5 nm Pr2O3 on a 1 nm thick AlOxNy layer. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/ds/session/23/contribution/4 SN - 0420-0195 SP - S. 243 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Burkov, Yevgen A1 - Henkel, Karsten A1 - Schmeißer, Dieter T1 - X-ray photoemission spectroscopy of Aluminium Oxynitride on Si(001) and the rise as buffer layers T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - Praseodymium oxide (PrxOy) is one of the candidate as high-k transistor gate dielectrics, but aluminium oxynitride (AlxONy) as buffer layer is needed to prevent diffusions from the silicon into PrxOy and to hinder charge injection from the semiconductor into the insulator. The thermal stability and thickness dependence of aluminum oxynitride (AlxONy) has been investigated by synchrotron radiation photoemission spectroscopy (SR-PES). AlxONy layers were prepared by low energy ion-beam assisted deposition (LE-IBAD) at room temperature on a silicon substrate cleaned with HF-acid. Aluminium oxynitride is stable till 800∘C. From photoemission spectra we can assess that silicon oxynitride is built as first and then the growth of AlxONy follows. Resonant inelastic X-ray scattering measurements with synchrotron radiation have been performed. The combination of X-ray absorption spectroscopy (XAS) and RIXS make possible to determinate the band gap of AlxONy. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/ds/session/23/contribution/5 SN - 0420-0195 SP - S. 243 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Henkel, Karsten A1 - Seime, Bernd A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - C(V) and C(t) measurements on MFIS structures consisting P[VDF/TrFE] as ferroelectric layer T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - Ferroelectric Field Effect Transistors (FeFETs) are considered as a candidate for future non volatile and non destructive readout memory cells. A possible low cost solution is the use of poly[vinylidene fluoride trifluoroethylene (P[VDF/TrFE]). Using P[VDF/TrFE] we focus on metal ferroelectric insulator semiconductor (MFIS) capacitor structures. In this contribution we will summarize our investigations related to capacitance measurements in dependence of applied bias (C(V)) and time (C(t)). The thickness of the ferroelectric layer as well as the thickness and the material of the buffer layer have been investigated for optimization of the write voltage. CV measurements at higher temperatures deliver decreased flatband voltage shifts within one CV loop resulting in lower memory windows. At temperatures around 100∘C the hysteresis totally vanished, pointing out the ferroelectric behavior of the system. C(t) measurements at a constant bias have been performed for retention analysis of the MFIS stack. After applying a writing pulse we could distinguish between a higher and a lower capacitance state for more than 5 days. This work is supported by Deutsche Forschungsgemeinschaft within priority program 1157 (SCHM 745/11-2). Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/sysa/session/4/contribution/7 SN - 0420-0195 SP - S. 828 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Karavaev, Konstantin A1 - Tallarida, Massimo A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried T1 - In-situ ALD growth of Hafnium oxide films T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - We report on a novel system for in-situ atomic layer growth (ALD) of high-k dielectric films. First results were obtained for Hf-oxide samples by using Hf-tetrachloride as precursor and water as oxidizer. We compare the photoelectron spectra of Si2p, O1s and Hf4f of our in-situ prepared films with samples (ex-situ) prepared by industrial ALD reactors and discuss similarities and differences observed in the core level spectra of the various samples by considering the different growth conditions. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/ds/session/23/contribution/12 SN - 0420-0195 SP - S. 244 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Mandal, Dipankar A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Dipole orientation of the P[VDF-TrFE] co-polymer films: A NEXAFS study T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - Ferroelectric properties of copolymers of vinylidene fluoride with trifluoroethylene (P[VDF-TrFE]) has become great deal of interest due to potential use in non volatile memory technology. Permanent dipoles (formed between the alternating hydrogen and fluorine atom within the copolymer) ordering of orientation are crucial for device efficiency. Here we focus on thickness dependence dipole orientation in these co-polymer films. In our systematic studies, we found there is prominent dipole re-orientation effect also for the intrinsic films (~10 nm thickness) before applying the electric field. It is observed after the application of the field, the dipoles re-oriented in opposite direction. Therefore, we conclude that the lowest thickness of the film should have well grown crystalline lamellae structure. As a result, c-axis of crystallites acts as well define manner in plane of the surface and for that reason the b-axis is more free. Because the b-axis is parallel to the polarization direction, it is easy to get a preferred orientation of the dipoles. For thicker films (here up to 100 nm), the average orientation effect is hindered, so a very low re-orientation effect has been observed. For this investigation, we used Near Edge X-ray Absorption Spectroscopy, at the U 49/2-PGM beam line of BESSY-II, Berlin. This work is supported by DFG within SPP1157 (SCHM 745/11-2). Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/sysa/session/5/contribution/76 SN - 0420-0195 SP - S. 840 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Klaus A1 - Mandal, Dipankar A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter T1 - Interface reactions of ferroelectric copolymer layers with different electrode materials T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 43 N2 - The ferroelectric copolymer poly(vinylidene fluoride trifluoroethylene) (P(VDF-TrFE)) is a possible material for low cost applications as organic nonvolatile memory element. We present an XPS interface investigation of the copolymer/electrode interface. Below 100nm film thickness, interface phenomena becomes important. Possible interface reactions could lead to a reduction of the ferroelectric functionality.We present a comparative study of the two interfaces Al/P(VDF-TrFE) and PEDOT:PSS/P(VDF-TrFE). The result is a clear indication of a surface reaction in between the Aluminum-electrodes. In contrast, for PEDOT:PSS the measurements shows a layer by layer formation of the interface PEDOT:PSS/PVDF without any reaction. Second, we present a study of remanent polarization of ultrathin spincoated films of the copolymer, in a thickness range from 5 to 100mn, with organic electrodes like PEDOT:PSS. The measurements are carried out by using the flatband shift of a capacitance-voltage (CV) characteristic. This shift of flatband voltage is used as value for the electric polarization of the polymer. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/sysa/session/5/contribution/16 SN - 0420-0195 SP - S. 830 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Sebastian A1 - Schmeißer, Dieter T1 - Direct Observation of d2L2 Charge Transfer States in TiO2 thin films by Resonant Photoelectron Spectroscopy T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - We investigate the electronic structure of TiO2 thin films by SR-PES, NEXAFS and ResPES. The films are prepared in a combined in-situ/ex-situ process that leads to stoichiometric thin films (≈ 10 nm) in Rutile structure. We focus on ResPES at the Ti 2p edge. When the photon energy is close to the Ti 2p absorption edge we observe additional features about 13 eV below the valence band main features. These features show clear spectator auger decay at the resonance leading to d0 final state. From this, we deduce the existence of the d2L2 initial charge transfer state as this is the only possible channel that enables the corresponding spectator auger decay. These features have the same origin as the satellite structures observed in core level spectra, esp. 2p and 3p. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/o/session/32/contribution/3 SN - 0420-0195 SP - S. 592 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried T1 - Photoemission and absorption spectroscopy for in situ investigations of the ALD growth T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - We have investigated the growth of Hf-oxide on Si by means of photoemission and X-ray absorption spectroscopy using synchrotron radiation at Bessy, Berlin. The Hf-oxide layers were grown via atomic layer deposition (ALD) using an in-situ ALD reactor attached to the investigation chamber. The XPS and XAS spectra were measured after every deposition cycle by transferring the sample into the investigation chamber without breaking the vacuum. From the experimental data we have obtained information about the early stages of the Hf-oxide growth, concerning in particular the reactivity of the interface with Si. Due to the possibility to study the layers after every cycle and with different oxidation parameters without exposing them to contaminants, the in situ investigation revealed to be a very important method to understand the growth properties of Hf-oxide. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/ds/session/22/contribution/5 SN - 0420-0195 SP - S. 242 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Opel, Matthias A1 - Nielsen, Karl-Wilhelm A1 - Bauer, Sebastian A1 - Goennenwein, Sebastian T. B. A1 - Gross, Rudolf A1 - Cezar, Julio C. A1 - Schmeißer, Dieter A1 - Simon, Jürgen A1 - Mader, Werner T1 - Ferromagnetism and magnetic clusters in cobalt-doped ZnO T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - Ferromagnetic semiconductors (FMS) - i.e. semiconductors exhibiting long-range magnetic ordering - are intriguing materials. However, in spite of intensive research in the last decade, the existence of homogeneous FMS with a Curie temperature around or above room temperature still is controversial. A particularly tedious issue are local sample inhomogeneities or magnetic clusters, which can yield strong magnetic signals resembling the behaviour expected for a homogeneous FMS. Using pulsed laser deposition, we have grown cobalt-doped ZnO films on single crystalline ZnO substrates. Combining x-ray magnetic circular dichroism, DC magnetometry, and AC susceptibility measurements with a detailed structural analysis by high resolution x-ray diffraction, transmission electron microscopy, and electron-spectroscopic imaging, we can unambigously trace the characteristic, ferromagnetic-like behaviour of our ZnO:Co samples at room-temperature to nanometer-sized superparamagnetic metallic cobalt precipitates. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/ma/session/3/contribution/6 SN - 0420-0195 SP - S. 430 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Lazareva, I. A1 - Koval, Yuri A1 - Müller, P. A1 - Paloumpa, Ioanna A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Field effect transistor of graphitized polyimide with P(VDF-TrFE) as gate insulator T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - Surfaces of polyimide films were graphitized by low-energy ion irradiation. The conductivity was between 10−5 to 200 S/cm [1]. We prepared field effect transistors using this material. Ferroelectric P(VDF-TrFE) was used as gate insulator. The thickness of P(VDF-TrFE) varied from 120 nm to 1200 nm. Properties of P(VDF-TrFE) were investigated by current-voltage measurements of metal/ P(VDF-TrFE)/metal capacitors. We have found that at room temperature, the coercive field of P(VDF-TrFE) does not depend on the film thickness. At lower temperatures the coercive field increases proportionally to the reciprocal temperature. Remnant polarization is 9.5 µC/cm2. It slightly rises with decreasing temperature. Our recent results of field effect mobility, carrier concentration and threshold voltage are presented. [1] I. Lazareva, Y. Koval, M. Alam, S. Strömsdörfer, P. Müller, Appl. Phys. Lett. 90, 262108 (2007) Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/df/session/11/contribution/6 SN - 0420-0195 SP - S. 195 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Bergholz, Matthias A1 - Sohal, Rakesh A1 - Schmeißer, Dieter T1 - ELS to determine the band gap of thin dielectric layers T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 41 N2 - In ultra thin layers of high-K materials the value of the band gap can be derived not explicitly although it is a key quantity in the electric behavior. We use ELS with a monochromatized (50 meV - 150 meV) electron gun and primary energies between 20 eV and 30 eV. Starting with the native SiO2/Si(001) layers we find that loss function of the substrate dominates for using primary energies beyond 50 eV. In contrast at energies below 50 eV the loss intensity can be used to derived the band gap with an accuracy of ±200 meV. We compare thin (<3 nm) films of HfOx, Pr2O3,Al2O3 and Si-Oxynitrides and discuss the band gap values as well as the scattered intensity observed within the gap. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/ds/session/8/contribution/2 SN - 0420-0195 SP - S. 156 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Henkel, Karsten A1 - Torche, Mohamed A1 - Schwiertz, Carola A1 - Paloumpa, Ioanna A1 - Sohal, Rakesh A1 - Müller, Klaus A1 - Schmeißer, Dieter T1 - Inorganic and organic layers for high-k and organic memory applications T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 41 N2 - We report about organic and inorganic MIS stacks for new possibilities for high frequency and high power applications as well as for non volatile memory cell. The organic stack contains a ferroelectric polymer as the functional layer. Poly[vinylidene fluoride trifluoroethylene] (P[VDF/TrFE]) is spin coated from a solution onto oxidised silicon substrates. We report on the polarisation induced flatband voltage shifts. For the inorganic stack our attempt is to combine higk-k dielectrics with high band gap semiconductors (SiC). Praseodymium oxide layers are prepared by electron beam evaporation from Pr6O11 powder and in situ controlling of interface and volume composition (XPS). Praseodymium silicate layers were prepared either by metal evaporation onto a thin ox- ide on top of the semiconductor and following annealing steps or by a wet chemical process out of aqueous Pr(NO3)3 solutions. Using spectro-scopic characterisation we investigate the stability of the various inter-faces within the stacks as well as the reactivity of the metal electrodes on thin Pr2O3. We report the results of electrical characterisation consisting of permittivity values, leakage current and density of interface states. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/df/session/1/contribution/4 SN - 0420-0195 SP - S. 127 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Klaus A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter T1 - P(VDF/TrFE) as ferroelectric insulation layer for organic field effect transistors T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 41 N2 - The ferroelectric polymer poly(vinylidene fluoride trifluoroethylene)(P(VDF-TrFE)) is used as insulating material for organic field effect tran-sistors (OFET) and metal-insulator-semiconductor (MIS)-structures. For the MIS-structures, we find the typical hysteresis in the CV charac-teristic upon increasing the voltage scan window. Based on these results, we fabricate OFET with regioregular poly(3-hexlythiophene)(P3HT) as organic semiconductor. The transistors are constructed in bottom gate architecture with thin layers of spincoated P(VDF-TrFE) as gate insulation (100nm). The drain-source current of the OFET is reversible affected by the polarized gate, which gives opportunities for organic nonvolatile memory elements. We present characteristic features like the hysteretic drain current response or the data retention. Furthermore, we present measurements with Kelvin probe force microscopy, a method which gives informations on the lateral distributions of the surface potential. Y1 - 2006 UR - http://www.dpg-verhandlungen.de/year/2006/conference/dresden/part/cpp/session/23/contribution/28 SN - 0420-0195 SP - S. 101 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Hoffmann, Patrick A1 - Schmeißer, Dieter A1 - Himpsel, Franz J. A1 - Engelmann, Hans-Jürgen A1 - Zschech, Ehrenfried A1 - Stegmann, Heiko A1 - Denlinger, Jonathan D. T1 - Characterization of Chemical Bonding in Low-K Dielectric Materials for Interconnect Isolation: XAS and EELS Study T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 41 N2 - The use of low dielectric constant materials in the on-chip interconnect process reduces interconnect delay, power dissipation and crosstalk noise. In CVD deposited organo-silicate glass (OSG) the substitution of oxygen in SiO2 by methyl groups (-CH3) reduces the permittivity significantly (from 4.0 in SiO2 to 2.6-3.3 in the OSG). However, plasma processing removes C and H containing molecular groups. Therefore, compositional analysis and chemical bonding characterization of structured films with nanometer resolution is necessary. OSG thin films as-deposited and after plasma treatment are studied using XAS and EELS. In both techniques, the fine structure near the C1s edge allows to identify C-H, C-C, and C-O bonds. XAS spectra have been recorded for non-patterned films and EELS spectra for patterned structures. The chemical bonding is compared for as-deposited and plasma-treated low-k materials. The flu-orescence and the electron yield recorded while XAS measurement are compared. Examination of the C 1s near-edge structures reveal a mod-ified bonding of the remaining C atoms in the plasma-treated sample regions. Y1 - 2006 SN - 0420-0195 SP - S. 156 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, P. A1 - Chowdhury, F. A1 - Dremov, V. A1 - Koval, Yuri A1 - Lichtenberg, F. A1 - Müller, S. A1 - Schmeißer, Dieter A1 - Pentcheva, R. T1 - Resistive memory switching in perovskite-derivative single crystals T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - We investigated several layered perovskite derivatives of the family AnBnO3n+2, such as LaTiO3.41, CaNbO3.41 and SrNbO3.41, which can be considered as a stacking of blocks consisting of 5 perovskite layers. Electric transport across these layers takes place via intrinsic tunnelling. Mesa devices with a cross-sectional area of 50 to 200 µm2 and a height between 30 and 500 nm were fabricated by electron-beam lithography and ion-beam etching. Both dc I-V characteristics and pulsed current injection have shown switching between different resistive states in these materials. The resistive states have long-term stability, which makes them interesting for memory applications. The transport experiments suggest that switching and resistive memory are controlled by trapping and release of charge carriers. Furthermore, photoelectron and NEXAFS spectroscopy of cleaved LaTiO3.41 surfaces have been performed. The results are compared to recent correlated band theory (LDA+U) calculations. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/synf/session/1/contribution/11 SN - 0420-0195 SP - S. 818 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Seifarth, Olaf A1 - Walczyk, Christian A1 - Lupina, Grzegorz A1 - Dabrowski, Jaroslaw A1 - Weidner, Günter A1 - Zaumseil, Peter A1 - Schmeißer, Dieter A1 - Storck, Peter A1 - Müssig, Hans-Joachim A1 - Schroeder, Thomas T1 - On the electronic and dielectric characterisation of thin cubic PrO2 layers on Silicon T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 43 N2 - For the integration of 100 % Ge onto the Si platform, a buffer oxide approach has been developed recently, using rare earth oxides to tune the lattice constant between the Si and the Ge. Among these buffer oxides, PrO2 is a prospective candidate with high quality crystalline growth on Si, moderated by an interfacial Pr-silicate between. In order to specify electronic properties of thin PrO2 and its interface on Si(111), especially the width of the band gap, we performed synchrotron radiation based XPS, UPS and XAS measurements at the U49/2 PGM 2 beamline at BESSY II and correlate the results with our structural characterisation performed by TEM and XRD. In order to evaluate the dielectric properties of thin PrO2 layers on Si(111), we performed temperature-, time-, voltage-, and layer thickness-dependent leakage current measurements (J-V). Here, we identified relaxation behaviour in the leakage current, successfully addressed to defect like states inside the Pr-silicate interface layer, corroborated by frequency dependent capacitance versus voltage (C-V) measurements. Y1 - 2008 UR - http://www.dpg-verhandlungen.de/year/2008/conference/berlin/part/df/session/12/contribution/6 SN - 0420-0195 SP - S. 196 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Friedrich, Daniel A1 - Michling, Marcel A1 - Klocek, Jolanta A1 - Schmeißer, Dieter A1 - Avdoshenko, Stas A1 - Chumakov, Dmytro A1 - Zschech, Ehrenfried T1 - Study of C60 based films formation by NEXAFS T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - The C60 fullerenes and some of its -OH, -CF3 and -Cl derivates are candidates for application as ultra-low-k insulators in the semiconductor industry. Future preparation of thin films based on these materials requires the stability of the substituted fullerenes against chemical handling and processing steps. The latter issue was addressed by our NEXAFS studies that were done by synchrotron radiation at the beam line U49/2-PGM2 at BESSY II. Performed were the C K-edge NEXAFS studies in total fluorescence and total electron yield modes. The C60 based films were deposited on silicon by spraying from solutions. The influence of the different substitutional groups with C60 molecules was studied. The data were compared to the reference spectra of a pure C60 film. For C60(OH)24, C60-Cl2 and C60(CF3)12 a variance of the intensity of the π*-resonance as well as shift to higher energies of 0.5 eV (-OH), 0.6 eV (-F), 0.7 eV (-Cl) were observed. The results confirm the necessary stability of the used C60 derivatives and shall be used for optimization of the film deposition chemistry and conditions. Y1 - 2009 SN - 0420-0195 SP - S. 145 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Karavaev, Konstantin A1 - Tallarida, Massimo A1 - Schmeißer, Dieter T1 - Evolution of the interfacial layer during the atomic layer deposition of HfO2 on Si/SiO2 substrates T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - We studied the formation of the interfacial layer in the Si/SiO2/HfO2 system using the in-situ Atomic Layer Deposition (ALD) reactor developed in our group [1,2]. We measured the X-ray photoelectron and X-ray absorption spectra with synchrotron radiation at the beamline U49-2/PGM2-BESSY II. The ALD growth was obtained using different Hf-precursors (HfCl4,TEMAHf and TDMAHf) on various prepared substrates at different temperatures. The investigation was carried out in-situ giving the possibility to determine the properties of the grown film after every ALD cycle without breaking the vacuum. We observed the evolution of the Si/SiO2/HfO2 system during the formation of first three Hf-oxide layers, detecting the interfacial growth of SiO2 during the initial ALD cycles from the XPS spectra of Si2p. We discuss how the interfacial layer growth depends on the various ALD parameters. [1] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Appl. Phys. 104, 064116 (2008); [2] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Vac. Sci. Technol. B, accepted for publication. Y1 - 2009 SN - 0420-0195 SP - S. 160 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Kolanek, Krzysztof A1 - Karavaev, Konstantin A1 - Tallarida, Massimo A1 - Schmeißer, Dieter T1 - In-situ investigations of the atomic layer deposition of HfO2 with UHV/AFM T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - We studied in-situ the atomic layer deposition (ALD) of HfO2 with ultra high vacuum (UHV) atomic force microscope (AFM), using the ALD reactor developed by our group [1, 2]. The reactor was attached to the Omicron Large Sample-UHV/AFM system in the AFM-Lab of the Angewandte Physik-Sensorik chair at the BTU-Cottbus. We investigated different Si(001)/SiO2 substrates and surface preparation techniques performed before the ALD process. After each ALD cycle (using TDMAHf and H2O as precursors), we studied the influence of the HfO2 growth on the root mean square (RMS) roughness; the surface fractal dimension and the height histogram: the surface skewness and kurtosis. We focused on the influence of the substrate temperature on the surface topography during the ALD. The in-situ studies of the ALD process with the UHV/AFM system correlated with the experiments performed with photoelectron spectroscopy can be used for understanding the fundamental properties of the ALD of HfO2 on Si(001). [1] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Appl. Phys. 104, 064116 (2008); [2] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Vac. Sci. Technol. B, accepted for publication. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/ds/session/11/contribution/6 SN - 0420-0195 SP - S. 160 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Kraatz, Matthias A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried A1 - Ho, Paul S. T1 - Electromigration simulation for on-chip Cu interconnects T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - We are investigating the influence of copper microstructure on electromigration degradation effects and interconnect lifetimes using computer simulation. The simulation is carried out in three dimensions. For the copper microstructure, a Monte Carlo technique was used to model the Cu grain growth. Different diffusivities where applied to grain boundaries and top interface of the interconnect model according to the qualitative crystallographic orientation of adjacent grains. The grain boundary network and the top interface form the diffusion paths for the electromigration mass transport. Along the diffusion paths, the fluxes of vacancies where calculated including mechanical stress and electromigration driving forces using a finite difference method. Positive flux divergent sites of the FDM lattice are treated as void nucleation sites after a critical vacancy concentration is reached. The resistance increase due to void growth was calculated using a cellular automaton, masking current free regions as quasi voids and adding the resistance of the slices of the lattice normal to the electron flow direction in series. A parallel computing environment was used to generate large numbers of interconnect models in order to obtain a pool of data for statistical analysis of interconnect lifetimes. The results of this analysis will be shown Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/ds/session/13/contribution/4 SN - 0420-0195 SP - S. 161 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Michling, Marcel A1 - Friedrich, Daniel A1 - Schmeißer, Dieter A1 - Koval, Yuri A1 - Müller, Paul T1 - Study of polyimide after graphitization with low-energy Ar+ Ion irradiation by NEXAFS T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - In this contribution we report on investigations of the electronic structure of Ar+ irradiated polyimide samples by using NEXAFS. The NEXAFS measurements were done at the U49/2-PGM2 beam line of BESSY II, Berlin using TEY and TFY detection. Polyimide samples are prepared using low Ar+ dose while the temperature of the samples is varied between 300K and 700K. In the NEXAFS data at the Carbon K-edge we see substantial changes between different samples. The differences appear in particular in the more surface sensitive TEY-Signal. The NEXFS data are consistent with the graphitization of the surface upon Ar+ bombardment as we identify the characteristic absorption bands of graphitic carbon. Its relative content increases with increasing sample temperature. In contrast, in the more bulk sensitive TFY data, the emission characteristic of polyimide is maintained. The possibility to cover insulating polymers with a conducting layer is a great demand for many applications. Because of the relative low price of the basic materials, the irradiation with low-energy Ions will play an important roll in the microelectronic of the future. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/df/session/15/contribution/5 SN - 0420-0195 SP - S. 147 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Müller, Sebastian A1 - Schmeißer, Dieter T1 - Investigation of ultra-thin Chromium layers on Titanium Dioxide by resonant photoemission T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - Oxide supported metal films and clusters offer interesting properties with a wide range of possible applications. In this context, Titanium Dioxide is chosen as a model substrate due to its simple electronic structure with a d0 configuration. We study the interaction of ultrathin Chromium films deposited on TiO2 film with focus on the modifications of the valence band and band gap region. Normal photoemission in bulk and surface sensitive modes as well as resonant photoemission at the Cr 2p and Ti 2p edges are used to distinguish the different Cr 3d and Ti 3d contributions to the valence band. In the initial step we find to gap states of distinct character with a sharp resonance of the Cr 3d related state at the Cr 2p edge. With increasing layer thickness we observe that this resonance extends to about 20 eV below the Fermi-Energy. Datasets of valence band spectra measured around the Cr 2p edge show 2 resonant mechanisms in this case i.e. a participator channel for the 3d state accompanied by a spectator channel at fixed kinetic energy. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/o/session/3/contribution/5 SN - 0420-0195 SP - S. 453 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Richter, Matthias A1 - Müller, Klaus A1 - Philip, Shine A1 - Paloumpa, Ioanna A1 - Henkel, Karsten A1 - Schmeißer, Dieter T1 - Temperature dependence of organic solar cell parameters T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 44 N2 - The influence of an annealing step on the parameters of bulk heterojunction organic solar cells is investigated. In order to fabricate the solar cells we use glass coated with ITO (Indiumtinoxide) as a substrate on which the active layer consisting of P3HT and PCBM is spincoated. Al-electrodes are evaporated on top of the active layer. We use PEDOT:PSS as buffer layer. Each sample is annealed at different temperatures for a short time. Between every temperature step the I-V characteristic of the cell is measured. The following parameters are derived afterwards: FF, Isc (density), Voc. Also the efficiency is estimated. The results show a maximum cell efficiency for drying at 100°C for 20sec. A further important step for preparation is the drying procedure of the PEDOT:PSS layer. Here an improvement of about 50% in cell efficiency is measured after drying at 50°C for 5 days under inert gas atmosphere. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/syop/session/4/contribution/2 SN - 0420-0195 SP - S. 671 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Kolanek, Krzysztof A1 - Schmeißer, Dieter T1 - Basics of the atomic layer deposition of HfO2 onto Si/SiO2 substrates: in-situ investigations with XPS, XAS and UHV-AFM T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 44 N2 - We developed a reactor for investigating in-situ the atomic layer deposition (ALD) of HfO2. X-ray photoelectron and X-ray absorption spectra were collected after each ALD cycle using synchrotron radiation at the beamline U49-2/PGM2 - BESSY II, Berlin. The morphology of the substrate and thin film surfaces was investigated after each ALD cycle with an UHV-AFM microscopy attached to the ALD reactor. We studied the ALD on differently prepared substrates, at different substrate temperatures, and using different Hf-precursors (HfCl4, TEMAHf, TDMAHf). We observed the evolution of the Si/SiO2/HfO2 system during the formation of the first three Hf-oxide layers [1]; we detected the incorporation of Cl into the Hf-oxide films and proposed a mechanism responsible for the Cl contamination [2]; we found evidence of the interfacial-SiO2 growth during the initial ALD cycles and of dipole formation at the HfO2/SiO2 interface. In this contribution we illustrate the basics of the technique used, and discuss the physical-chemical properties of ALD on the basis of the experimental results. [1] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Appl. Phys. 104, 064116 (2008); [2] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Vac. Sci. Technol. B, accepted for publication. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/ds/session/11/contribution/4 SN - 0420-0195 SP - S. 159 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Tallarida, Massimo A1 - Karavaev, Konstantin A1 - Kolanek, Krzysztof A1 - Schmeißer, Dieter T1 - In-situ experimental approach to the study of atomic layer deposition with atomic force microscope, X-ray photoelectron and X-ray absorption spectroscopy T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft ; Reihe 6, Bd. 44 N2 - We describe our experimental approach to the investigation of atomic layer deposition (ALD). ALD is a powerful deposition technique for growing conformal thin films of composite materials with atomically accurate thickness on large area [1]. Despite the enormous industrial interest growing around ALD, its fundamental properties were not yet properly studied. We developed an ALD reactor for the in-situ investigations using XPS, XAS and AFM as experimental techniques. We studied the chemical-physical properties of the growing thin films after each deposition cycle. Here, we illustrate the recent results concerning the ALD of HfO2 obtained using different Hf-precursors on various substrates [2]. We show how the in-situ investigations could deliver an important insight into the fundamental characteristics of ALD and how these information could be used to modify and optimize the deposition parameters. [1] M. Leskelä, M. Ritala, Thin Solid Films, 409, 138, 2002; [2] M. Tallarida, K. Karavaev, and D. Schmeisser, J. Appl. Phys. 104, 064116 (2008). Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/ds/session/26/contribution/15 SN - 0420-0195 SP - S.176 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Seifarth, Olaf A1 - Walczyk, Christian A1 - Lupina, Grzegorz A1 - Zaumseil, Peter A1 - Schmeißer, Dieter A1 - Müssig, Hans-Joachim A1 - Schroeder, Thomas T1 - The electronic band diagram of thin PrO2(111) / Pr-silicate buffers on Si(111) and its relevance to dielectric properties T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 44 N2 - Thin dielectric buffers of cubic PrO2(111) on Si(111) are ideally suited to integrate Ge onto Si by moderating the lattice mismatch between the materials. The leakage current across this dielectric buffer is strongly influenced by the electronic band diagram and defects inside the band gap. Therefore, we measured the band offsets, band gaps and defect positions by means of synchrotron radiation based photoemission spectroscopy techniques (XPS and XAS) with special emphasis on the Pr-silicate interface. In a next step we compare the spectroscopic data with information from dielectric studies, based on temperature dependent leakage current studies. We observe a close relation between dielectric properties and the electronic structure. Y1 - 2009 UR - http://www.dpg-verhandlungen.de/year/2009/conference/dresden/part/df/session/6/contribution/5 SN - 0420-0195 SP - S. 136 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Friedrich, Daniel A1 - Michling, Marcel A1 - Schmeißer, Dieter A1 - Koval, Yuri A1 - Müller, Paul T1 - Characterization of ion beam modified polyimide layers T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Ion beam modified polyimide show high conductivity. In our investigation we focus on the electronic structure and the element composition, in order to understand the mechanism of conductivity. In our experiments we use the methods NEXAFS and PES. The measurements were done at the U49/2-PGM2 beam line of BESSY II, Berlin. We find an increase of the sp2 hybridized graphite contribution, after low Ar+ ion doses bombardment while the temperature of the samples is varied from 300 K to 650 K. In addition we follow the He+ bombardment induced changes by in-situ monitoring of the O1s, N1s content in the polyimide films. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/38/contribution/10 SN - 0420-0195 SP - S. 247 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Dudek, Peter A1 - Lupina, Grzegorz A1 - Kozłowski, Grzegorz A1 - Dabrowski, Jarek Marek A1 - Lippert, Gunther A1 - Müssig, Hans-Joachim A1 - Schmeißer, Dieter A1 - Schroeder, Thomas T1 - Band structure and electrical properties of MBE grown HfO2 - based alkaline earth perovskites T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 45 N2 - Ultra thin dielectric films (<20 nm) deposited on TiN electrodes are interesting for MIM capacitor application. High capacitance density and dielectric permittivity must be accompanied by extremely low leakage currents (10−8 A/cm2) at bias 0.5 V. To achieve such low leakage currents, high band gap and proper band alignment is required. Occupied electronic states can be probed with standard laboratory photoemission methods. Probing of unoccupied states is more challenging. Synchrotron based PES in combination with XAS forms a powerful method to study the band alignment. ASAM end station located at the U 49/2 PGM 2 beamline of BESSY II (Berlin) offers excellent conditions for performing such measurements. We investigated HfO2 - based alkaline earth perovskite - BaHfO3 with subsequent admixture of TiO2, resulting in formation of BaHf0.5Ti0.5O3 compound. The analysis of data indicates that band gap for HfO2 is similar to BaHfO3 and amounts 5.8 eV; for BaHf0.5Ti0.5O3 it decreases to 3.8 eV. We conclude that the addition of TiO2 to BaHfO3 increases significantly the dielectric permittivity but also impacts the band gap alignment. The conduction band offset shrinks, influencing the leakage current behavior. Y1 - 2010 UR - http://www.dpg-verhandlungen.de/year/2010/conference/regensburg/part/ds/session/24/contribution/4 SN - 0420-0195 SP - S. 232 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Friedrich, Daniel A1 - Koval, Yuri A1 - Müller, Paul A1 - Schmeißer, Dieter T1 - Electronic structure of thin spin-coated polyimide layers T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 46 N2 - The conductivity of polyimide layers can be modified by several orders of magnitude by ion beam radiation. In order to understand the electronic structure of the pure polyimide before ion beam modification we focus in our preliminary experiments on spectroscopic investigations of thin as prepared polyimide films. The films were made by spin coating from a PMDA/ODA solution with subsequent vacuum annealing at 350°C. The layer thickness can be controlled by changing the concentration of PMDA/ODA in the solution realizing a thickness down to 3.5nm. For the characterization of the as prepared thin polyimide films the techniques NEXAFS, ResPES, XPS and CIS were applied at the U49/2-PGM2 beam line of Bessy II, Berlin. Our data including the valence band, core levels and absorption spectrum were compared with theoretical LCAO calculations. Based on these results we are able to attribute all spectral features to the specific atomic bonds in the molecule. Y1 - 2011 UR - http://www.dpg-verhandlungen.de/year/2011/conference/dresden/part/ds/session/63/contribution/3 SN - 0420-0195 SP - S. 311 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Hoffmannbeck, David A1 - Richter, Matthias A1 - Städter, Matthias A1 - Paloumpa, Ioanna A1 - Henkel, Karsten A1 - Schmeißer, Dieter T1 - Spectroscopic and microscopic characterization of potential catalysts for the hydrogenation of CO2 T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 46 N2 - The reduction of CO2 emissions is a general demand of the society in order to avoid irreversible climate changes. We are investigating potential catalysts for the hydrogenation of CO2 in particular for its application in the so called oxyfuel combustion process. In order to understand the catalytic behavior of the investigated materials we use the techniques X-Ray Photoemission (XPS) and -absorption (XAS) Spectroscopy as well as X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The prospective of our work is to figure out the electronic and structural properties of the material and to optimize proper catalysts or design new ones for best catalytic activity. Beside the spectro-microscopic investigations the catalysts are tested under Sabatier reaction conditions in terms of activity, stability and sensitivity against poisoning. In our preliminary work we constructed a Sabatier reactor system with analytical parts based on infrared absorption and mass spectroscopy modules. First spectroscopic and catalytic results achieved on a commercially available Ru/Al2O3 catalyst will be presented. Y1 - 2011 UR - http://www.dpg-verhandlungen.de/year/2011/conference/dresden/part/o/session/60/contribution/123 SN - 0420-0195 SP - S. 483 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Kraatz, Matthias A1 - Zhang, Lijuan A1 - Schmeißer, Dieter A1 - Zschech, Ehrenfried A1 - Ho, Paul S. T1 - Statistical Analysis of Computer-simulated On-Chip Interconnect Electromigration Lifetimes under the Influence of Microstructure and Strengthened Top Interface T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 46 N2 - We are investigating the statistics of computer-simulated interconnect electromigration (EM) lifetimes with regard to the effects of microstructure and a strengthened top interface. The degradation process of EM once threatened the entire existence of integrated circuit industry in the 1960s and has remained a major reliability concern. Ongoing miniaturization and the introduction of new materials further complicate the task of EM-resistant chip manufacturing. We have developed a simple two-dimensional finite difference simulation that models the mass transport by electromigration along the grain boundaries and the top interface of interconnect segments that allows us to do calculations of void nucleation and growth. A parallel computer simulates hundreds of interconnects simultaneously and statistical analysis becomes feasible. A Monte Carlo grain growth algorithm (a modified Potts version) is applied to model the grain structure of the interconnect segments. We will show that the simulation can be used to compare simulation and experiment qualitatively. Four cases have been studied: interconnect segments with small/large grains and weak/strong top interface. Y1 - 2011 UR - http://www.dpg-verhandlungen.de/year/2011/conference/dresden/part/ds/session/7/contribution/2 SN - 0420-0195 SP - S. 292 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Mbua, Roy A1 - Müller, Klaus A1 - Richter, Matthias A1 - Henkel, Karsten A1 - Paloumpa, Ioanna A1 - Schmeißer, Dieter A1 - Kramm, Ulricke T1 - Investigation of new Catalysts for PEM Fuel Cells T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 46 N2 - Increasing green house emissions amplify global warming concerns worldwide. Fuel cells, based on polymer electrolyte membranes (PEM) are part of the solution to this issue. We aim at developing and testing new catalysts for fuel cells. Platinum catalysts perform best in PEM fuel cells to date but they are very expensive. For fuel cells to be perfectly applicable and economically affordable, an alternative catalyst with similar or even greater efficiency should be developed. Metal phthalocyanines are known to be good oxygen reduction catalysts and are associated with high electron transfer properties. We investigated Cobalt Phthalocyanine in its pure state mixed with Carbon Black (CoPc:Carbon Black=1:9) untreated and also after a treatment in N2 at several temperatures, up to 1000°C for 30 minutes. Results of XPS and EDX analyses reveal that the treatment at higher temperatures causes a rearrangement in the chemical states of Co, N and C atoms. Furthermore, results of cycling voltammetry (CV) analysis reveal that CoPc treated in N2 at 800°C exhibited a higher current density, in conclusion, a higher catalytic activity than the untreated CoPc. Y1 - 2011 UR - http://www.dpg-verhandlungen.de/year/2011/conference/dresden/part/o/session/60/contribution/119 SN - 0420-0195 SP - S. 483 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Michling, Marcel A1 - Kolanek, Krzysztof A1 - Schmeißer, Dieter A1 - Tallarida, Massimo T1 - A growth model for the HfO2 ALD process T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft, Reihe 6, Bd. 46 N2 - In this contribution we report on our in-situ2 cycle-by-cycle (up to the 25 cycles) investigation of the HfO2 atomic layer deposition (ALD) process using the method of x-ray photoelectron spectroscopy (XPS) and electron energy loss spectroscopy (EELS). We used Tetrakis-Dimethyl-Amino-Hafnium (TDMA-Hf) and H2O as precursors and p-type Si wafer with native oxide as a substrate. The XPS measurements were carried out at BESSY II in Berlin with primary energies of 150 eV and 640 eV and the EELS measurements were done with a primary energy of 50 eV. We measured the O1s, Si2p core level and the valence band including the Hf 4f core level. From the Hf4f to Si2p ratios taken at each energy we developed a growth model for the first monolayer and for the following layers too. From our data we conclude, that in the first monolayer up to the fourth ALD cycle an island growth occurs. The height of these islands is about 0,5nm. After the first monolayer is completed, a layer- by-layer growth can be expected. In order to proof this observation we have simulated the Hf/Si ratio for different excitation energies and found a very good agreement with our measurement data. The EELS data especially the evaluation of the loss function onset confirm our growth model. Y1 - 2011 UR - http://www.dpg-verhandlungen.de/year/2011/conference/dresden/part/ds/session/12/contribution/1 SN - 0420-0195 SP - S. 294 PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER -