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 - 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 - GEN A1 - Lippert, Gunther A1 - Dabrowski, Jarek Marek A1 - Oberbeck, Lars A1 - Schroeder, Uwe A1 - Costina, Ioan A1 - Lupina, Grzegorz A1 - Ratzke, Markus A1 - Zaumseil, Peter A1 - Müssig, Hans-Joachim T1 - Morphology and composition of selected high-k materials and their relevance to dielectric properties of thin films T2 - Journal of the electrochemical society Y1 - 2008 U6 - https://doi.org/10.1149/1.2875741 SN - 1945-7111 VL - 155 IS - 5 SP - G97 EP - G114 ER - TY - CHAP A1 - Torche, Mohamed A1 - Müller, Klaus A1 - Henkel, Karsten A1 - Lupina, Grzegorz A1 - Goryako, Andrey A1 - Wollweber, Jürgen A1 - Schmeißer, Dieter T1 - Investigations of 3C-SiC growth on Si (001) T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft N2 - Carbide was grown on Si (001) - substrates with supply of C2H2. Investigation of the interface Si/SiC (buffer layer) is essential for optimized preparation conditions, leading to a high quality of the growing SiC crystal. In addition to the lattice mismatch of 20 per cent between Si and SiC, which causes defects like dislocations or stacking faults, the chemical homogeneity of this layer is important. XPS was used to characterize the first state of SiC crystal growth on the Si substrate. Carbonizing with C2H2 leads to surface reactions which build up the buffer layer. By using electron spectroscopy, it was possible to characterize the SiC/Si (001) buffer layer, depending on the following reaction parameters: Tsubstrate , PC2H2 , PH2 , the ratio of pressures and the reaction time. The measurements were performed in terms of the content of carbide, oxide and roughness/etching-efficiency (Profilometer) for the reaction parameters above. We found, that the most critical parameter is the temperature of the substrate (Tsubstrate). KW - 3C-SiC KW - chemical vapor deposition (CVD) KW - X-ray photoelectron spectroscopy (XPS) Y1 - 2004 UR - http://www.dpg-verhandlungen.de/year/2004/conference/regensburg/part/hl/session/44/contribution/42?lang=de PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - CHAP A1 - Lupina, Grzegorz A1 - Schroeder, Thomas A1 - Dabrowski, Jarek Marek A1 - Schmeißer, Dieter A1 - Müssig, Hans-Joachim T1 - Ti-doping of Pr silicate layers for high-k dielectrics applications T2 - Verhandlungen der Deutschen Physikalischen Gesellschaft N2 - Near-term downscaling of the metal-oxide-semiconductor field-effect transistors (MOSFETs) requires the replacement of the SiO2 gate oxide with a material having a higher dielectric constant. Recent studies indicate that silicate materials are the most promising candidates; among them are Pr silicates. Applying a combination of x-ray photoelectron spectroscopy (XPS), electrical measurements (C-V), and ab initio calculations, we investigated the effect of thin Ti doping on the structural and electrical properties of the gate stacks composed of a Pr silicate film and a SiO2-based interfacial buffer layer. Metallic Ti was deposited at room temperature after the formation of the Pr silicate dielectric. The resulting layered structures were annealed under ultra-high vacuum (UHV) at various temperatures between 70∘C and 880∘C. XPS indicates that the evaporated layer preserves its metallic character over the whole range of UHV annealing temperatures. Synchrotron radiation XPS at BESSY II shows that large amounts of Ti atoms incorporated into the Pr silicate remain metallic even after air exposure at room temperature. Annealing in nitrogen ambient at 300∘C leads to the oxidation of these atoms so that a mixed Pr:Ti silicate is formed. We show that the so formed dielectrics exhibit an improved equivalent oxide thickness and a reduced density of interface states. KW - high-k KW - X-ray photoelectron spectroscopy KW - ab inito calculations KW - Capacitance-voltage measurements KW - Pr silicate Y1 - 2005 UR - http://www.dpg-verhandlungen.de/year/2005/conference/berlin/part/df/session/6/contribution/5?lan=en PB - Deutsche Physikalische Gesellschaft CY - Bad Honnef ER - TY - GEN A1 - Niu, Gang A1 - Capellini, Giovanni A1 - Lupina, Grzegorz A1 - Niermann, Tore A1 - Salvalaglio, Marco A1 - Marzegalli, Anna A1 - Schubert, Markus Andreas A1 - Zaumseil, Peter A1 - Krause, Hans-Michael A1 - Skibitzki, Oliver A1 - Lehmann, Michael A1 - Montalenti, Francesco A1 - Xie, Ya-Hong A1 - Schröder, Thomas T1 - Photodetection in hybrid single layer graphene/fully coherent Ge island nanostructures selectively grown on Si nano-tip patterns T2 - ACS Applied Materials and Interfaces Y1 - 2016 SN - 1944-8252 VL - 8 IS - 3 SP - 2017 EP - 2026 ER - TY - GEN A1 - Dabrowski, Jarek Marek A1 - Lippert, Gunther A1 - Avila, J. A1 - Baringhaus, Jens A1 - Colambo, I. A1 - Dedkov, Yu. S. A1 - Herziger, Felix A1 - Lupina, Grzegorz A1 - Maultzsch, J. A1 - Schaffus, T. A1 - Schröder, Thomas A1 - Sowinska, Małgorzata A1 - Tegenkamp, Christoph A1 - Vignaud, D. A1 - Asensio, Maria Carmen T1 - Understanding the growth mechanism of graphene on Ge/Si(001) surfaces T2 - Scientific Reports Y1 - 2016 U6 - https://doi.org/10.1038/srep31639 SN - 2045-2322 IS - 6 SP - Art. 31639 ER - TY - GEN A1 - Bartolomeo, Antonio di A1 - Passacantando, Maurizio A1 - Niu, Gang A1 - Schlykow, Viktoria A1 - Lupina, Grzegorz A1 - Giubileo, Filippo A1 - Schröder, Thomas T1 - Observation of field emission from GeSn nanoparticles epitaxially grown on silicon nanotip arrays T2 - Nanotechnology Y1 - 2016 SN - 1361-6528 SN - 0957-4484 VL - 27 IS - 48 SP - 485707 ER - TY - GEN A1 - Lukosius, Mindaugas A1 - Dabrowski, Jarek Marek A1 - Lisker, Marco A1 - Kitzmann, Julia A1 - Schulze, Sebastian A1 - Lippert, Gunther A1 - Fursenko, Oksana A1 - Yamamoto, Yuji A1 - Schubert, Markus Andreas A1 - Krause, Hans-Michael A1 - Wolff, Andre A1 - Mai, A. A1 - Schröder, Thomas A1 - Lupina, Grzegorz T1 - Metal-free, CVD Graphene synthesis on 200 mm Ge / Si(001) substrates T2 - ACS Applied Materials and Interfaces Y1 - 2016 U6 - https://doi.org/10.1021/acsami.6b11397 SN - 1944-8244 SN - 1944-8252 VL - 8 IS - 49 SP - 33786 EP - 33793 ER - TY - GEN A1 - Bartolomeo, Antonio di A1 - Giubileo, Filippo A1 - Romeo, Francesco A1 - Sabatino, Paolo A1 - Carapella, Giovanni A1 - Iemmo, Laura A1 - Schröder, Thomas A1 - Lupina, Grzegorz T1 - Graphene field effect transistors with Niobium contacts and asymmetric transfer characteristics T2 - Nanotechnology Y1 - 2015 SN - 1361-6528 SN - 0957-4484 VL - 26 IS - 47 SP - 475202 ER -