TY - CHAP A1 - Schreiner, Rupert A1 - Langer, Christoph A1 - Prommesberger, Christian A1 - Mingels, Stephan A1 - Serbun, Pavel A1 - Müller, Günter T1 - Field emission from surface textured extraction facets of GaN light emitting diodes T2 - 26th International Vacuum Nanoelectronics Conference (IVNC), 8-12 July 2013, Roanoke, VA, USA N2 - We report on the field emission properties of GaN LED surfaces. The textured extraction facet acts both as light scattering layer in order to increase the light extraction efficiency of the LED as well as nanostructured cathode surface for the field emission (FE) of electrons. The LED emits blue light with a peak wavelength of around 450 nm. The FE properties were investigated by a scanning microscope. Integral measurements as well as regulated voltage scans for 1 nA FE current over an area of 400 * 400 µm2were used to investigate both overall and local FE properties. A high number of well-distributed emitters with an average field enhancement factor ß of 85 and stable integral emission currents up to 100 µA at an electric field of   80 V/µm (Øanode= 880 µm) were found. Photo-field-emission spectroscopy (PFES) using a tunable pulsed laser revealed an enhanced photo absorption of the InGaN/GaN quantum well structures near the emission wavelength of the LED (<3.5 eV), whereas at high photon energies (>4.1 eV) photoemission from the GaN surface was observed. KW - Gallium nitride KW - Iron KW - Light emitting diodes KW - Cathodes KW - Surface texture KW - Surface waves KW - Photonics Y1 - 2013 U6 - https://doi.org/10.1109/ivnc.2013.6624721 PB - IEEE ER - TY - CHAP A1 - Navitski, Aliaksandr A1 - Serbun, Pavel A1 - Müller, Günter A1 - Schreiner, Rupert A1 - Dams, Florian T1 - Efficient and reliable field emission from silicon tip arrays for miniaturized electron sources T2 - 2011 24th International Vacuum Nanoelectronics Conference ; 18-22 July 2011 Wuppertal N2 - Silicon-based cathodes with precisely aligned field emitter arrays (FEA) applicable for miniaturized electron sources were successfully developed and fabricated. The cathode chips contain about 3×105 Si tips/cm2 in a triangular array with a tip height of 2.5 μm, tip radius of 20 nm, and lateral distance between tips of 20 μm. Amazingly homogeneous and well-aligned field emission (FE) from all tips (i.e. 100% efficiency) and maximum stable currents of typically 0.1 μA for p- and 0.6 μA for n-type Si were reproducibly achieved. Current-voltage characteristics of p-type Si tips exhibit the expected saturation at around 10 nA due to limited supply of electrons from a depletion layer, while the n-type Si tips show the usual FN behaviour. Additional coating of the Si tips with a 10 nm Au layer resulted in at least 5 times higher average FE current levels i.e. typically 3 μA but lead, however, to a 30% increase of the onset voltage. KW - cathodes KW - coatings KW - elemental semiconductors KW - field emission KW - field emitter arrays KW - miniaturized electron sources KW - silicon tips KW - structured cold cathode Y1 - 2011 UR - https://ieeexplore.ieee.org/document/6004567?arnumber=6004567 SN - 978-3-00-035081-8 SN - 978-1-4577-1243-2 SN - 2380-6311 SN - 2164-2370 SP - 71 EP - 72 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Pirker, Luka A1 - Ławrowski, Robert Damian A1 - Schreiner, Rupert A1 - Remškar, Maja A1 - Višić, Bojana T1 - MoₓWₓ₋₁S₂ Nanotubes for Advanced Field Emission Application JF - Advanced Functional Materials N2 - Transition metal dichalcogenide (TMDC) nanotubes complement the field of low-dimensional materials with their quasi-1D morphology and a wide set of intriguing properties. By introducing different transition metals into the crystal structure, their properties can be tailored for specific purpose and applications. Herein, the characterization and a subsequent preparation of single-nanotube field emission devices of MoxWx-1S2 nanotubes prepared via the chemical vapor transport reaction is presented. Energy-dispersive X-ray spectroscopy, Raman spectroscopy, and X-ray diffraction indicate that the molybdenum and tungsten atoms are randomly distributed within the crystal structure and that the material is highly crystalline. High resolution transmission electron microscopy and electron diffraction (ED) patterns further corroborate these findings. A detailed analysis of the ED patterns from an eight-layer nanotube reveal that the nanotubes grow in the 2H structure, with each shell consists of one bilayer. The work function of the nanotubes is comparable to that of pure MoS2 and lower of pure WS2 NTs, making them ideal candidates for field emission applications. Two devices with different geometrical setup are prepared and tested as field emitters, showing promising results for single nanotube field emission applications. Y1 - 2023 U6 - https://doi.org/10.1002/adfm.202213869 SN - 1616-3028 N1 - Early View. Online Version of Record before inclusion in an issue SP - 1 EP - 8 PB - Wiley ER - TY - JOUR A1 - Broser, Christian A1 - Falter, Thomas A1 - Ławrowski, Robert Damian A1 - Altenbuchner, Amelie A1 - Vögele, Daniel A1 - Koss, Claus A1 - Schlamp, Matthias A1 - Dunnweber, Jan A1 - Steffens, Oliver A1 - Heckner, Markus A1 - Jaritz, Sabine A1 - Schiegl, Thomas A1 - Corsten, Sabine A1 - Lauer, Norina A1 - Guertler, Katherine A1 - Koenig, Eric A1 - Haug, Sonja A1 - Huber, Dominik A1 - Birkenmaier, Clemens A1 - Krenkel, Lars A1 - Wagner, Thomas A1 - Justus, Xenia A1 - Saßmannshausen, Sean Patrick A1 - Kleine, Nadine A1 - Weber, Karsten A1 - Braun, Carina N. A1 - Giacoppo, Giuliano A1 - Heinrich, Michael A1 - Just, Tobias A1 - Schreck, Thomas A1 - Schnabl, Andreas A1 - Gilmore, Amador Téran A1 - Roeslin, Samuel A1 - Schmid, Sandra A1 - Wellnitz, Felix A1 - Malz, Sebastian A1 - Maurial, Andreas A1 - Hauser, Florian A1 - Mottok, Jürgen A1 - Klettke, Meike A1 - Scherzinger, Stefanie A1 - Störl, Uta A1 - Heckner, Markus A1 - Bazo, Alexander A1 - Wolff, Christian A1 - Kopper, Andreas A1 - Westner, Markus A1 - Pongratz, Christian A1 - Ehrlich, Ingo A1 - Briem, Ulrich A1 - Hederer, Sebastian A1 - Wagner, Marcus A1 - Schillinger, Moritz A1 - Görlach, Julien A1 - Hierl, Stefan A1 - Siegl, Marco A1 - Langer, Christoph A1 - Hausladen, Matthias A1 - Schreiner, Rupert A1 - Haslbeck, Matthias A1 - Kreuzer, Reinhard A1 - Brückl, Oliver A1 - Dawoud, Belal A1 - Rabl, Hans-Peter A1 - Gamisch, Bernd A1 - Schmidt, Ottfried A1 - Heberl, Michael A1 - Gänsbauer, Bianca A1 - Bick, Werner A1 - Ellermeier, Andreas A1 - Monkman, Gareth J. A1 - Prem, Nina A1 - Sindersberger, Dirk A1 - Tschurtschenthaler, Karl A1 - Aurbach, Maximilian A1 - Dendorfer, Sebastian A1 - Betz, Michael A. A1 - Szecsey, Tamara A1 - Mauerer, Wolfgang A1 - Murr, Florian ED - Baier, Wolfgang T1 - Forschung 2018 T3 - Forschungsberichte der OTH Regensburg - 2018 KW - Forschung KW - Forschungsbericht Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-13826 SN - 978-3-9818209-5-9 CY - Regensburg ER - TY - JOUR A1 - Rück, Thomas A1 - Bierl, Rudolf A1 - Lechner, Alfred A1 - Graf, Antonia A1 - Dams, Florian A1 - Schreiner, Rupert A1 - Auchter, Eberhard A1 - Kriz, Willy A1 - Deubzer, MIchael A1 - Schiller, Frank A1 - Mottok, Jürgen A1 - Niemetz, Michael A1 - Margull, Ulrich A1 - Hagel, Georg A1 - Utesch, Matthias A1 - Waldherr, Franz A1 - Böhm, Matthias A1 - Fraunhoffer, Judith A1 - Gardeia, Armin A1 - Schneider, Ralph A1 - Streubel, Janet A1 - Landes, Dieter A1 - Studt, Reimer A1 - Peuker, Dominik A1 - Scharfenberg, Georg A1 - Hook, Christian A1 - Schuster, Dietwald A1 - Ehrlich, Ingo A1 - Dinnebier, Heinrich A1 - Briem, Ulrich A1 - Lämmlein, Stephan A1 - Koder, Alexander A1 - Bialek, Adam A1 - Genewsky, Axel A1 - Neumeier, Michael A1 - Schlosser, Philipp A1 - Rabl, Hans-Peter A1 - Paule, Matthias A1 - Galster, Christoph A1 - Schiedermeier, Michael A1 - Zwickel, Andreas A1 - Hobmeier, Christoph A1 - Bischoff, Tobias A1 - Rill, Georg A1 - Schaeffer, Thomas A1 - Arbesmeier, Martin A1 - Groß, Andreas A1 - Schlegl, Thomas A1 - Becker, Mark A1 - Senn, Konrad A1 - Schliekmann, Claus A1 - Scholz, Peter A1 - Sippl, Christian A1 - Grill, Martin ED - Eckstein, Josef T1 - Forschungsbericht 2011 / Hochschule für Angewandte Wissenschaften - Fachhochschule Regensburg T3 - Forschungsberichte der OTH Regensburg - 2011 Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-7321 SN - 1868-3533 CY - Regensburg ER - TY - CHAP A1 - Herdl, Florian A1 - Bachmann, Michael A1 - Wohlfartsstätter, Dominik A1 - Düsberg, Felix A1 - Dudeck, Markus A1 - Eder, Magdalena A1 - Meyer, Manuel A1 - Pahlke, Andreas A1 - Edler, Simon A1 - Schels, Andreas A1 - Hansch, Walter A1 - Schreiner, Rupert A1 - Wohlfartsstatter, Dominik A1 - Dusberg, Felix T1 - A novel current dependent field emission performance test T2 - 2021 34th International Vacuum Nanoelectronics Conference (IVNC): 5-9 July 2021, Lyon, France N2 - A current dependent performance test for comparison of different field emitter arrays is introduced. Statistical analysis is enabled due to a short measurement time and as a main feature the electric field shift, comparable to the degradation of the emitter is examined. Significance of the test method is shown by a comparison of field emitter arrays with different doping levels. KW - Current measurement KW - Field emitter arrays KW - Statistical analysis KW - Systematics KW - Time measurement KW - Tools KW - Vacuum systems Y1 - 2021 U6 - https://doi.org/10.1109/IVNC52431.2021.9600695 SP - 1 EP - 2 ER - TY - CHAP A1 - Bieker, Johannes A1 - Roustaie, Farough A1 - Schlaak, Helmut F. A1 - Langer, Christoph A1 - Schreiner, Rupert T1 - Field emission characterization of in-situ deposited metallic nanocones T2 - 2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany N2 - An in-situ fabrication technique based on ion track etched template electrodeposition of metallic nanocones was used for the production of field emitter cathodes. Gold nanocones with a height of 24 microns, a base diameter between 3 to 4 microns and a tip diameter below 300 nanometers were deposited on a circular electrode with a diameter of 2.5 mm. The integral field emission (FE) measurements of samples with cone densities of 6 · 104 cones/cm2 (sample A) and 1 · 106 cones/cm2 (sample B) yielded in a maximum current of 37.5 μA at an applied field of 12.5 V/μm for sample A and 29.1 μA at 9.4 V/μm for sample B. The stability of emission current was investigated for over 48 hours and no degradation was observed. KW - CATHODES KW - Current measurement KW - FABRICATION KW - field emission KW - ion track template KW - Ions KW - Iron KW - nanocones KW - Vacuum technology KW - Voltage measurement Y1 - 2017 U6 - https://doi.org/10.1109/IVNC.2017.8051571 SP - 120 EP - 121 PB - IEEE ER - TY - CHAP A1 - Schels, Andreas A1 - Edler, Simon A1 - Hansch, Walter A1 - Bachmann, Michael A1 - Herdl, Florian A1 - Dusberg, F. A1 - Eder, Magdalena A1 - Meyer, Manuel A1 - Dudek, M. A1 - Pahlke, Andreas A1 - Schreiner, Rupert ED - Purcell, Stephen ED - Mazellier, Jean-Paul T1 - Current dependent performance test used on different types of silicon field emitter arrays T2 - 2021 34th International Vacuum Nanoelectronics Conference (IVNC): 5-9 July 2021, Lyon, France N2 - A current dependent performance test is used to investigate the influence of doping and emitter geometry on the lifetime of silicon field emitter arrays. The measurements reveal an improved performance for lower n-type dopant concentrations. Furthermore, two new types of field emitters are introduced by slightly varying the original fabrication process [1]. The comparison shows superiority of tip like emitters over blade like structures. Y1 - 2021 SN - 978-1-6654-2589-6 U6 - https://doi.org/10.1109/IVNC52431.2021.9600787 SP - 1 EP - 2 PB - IEEE CY - Piscataway, NJ ER - TY - JOUR A1 - Schels, Andreas A1 - Herdl, Florian A1 - Hausladen, Matthias A1 - Wohlfartsstätter, Dominik A1 - Edler, Simon A1 - Bachmann, Michael A1 - Pahlke, Andreas A1 - Schreiner, Rupert A1 - Hansch, Walter T1 - Quantitative Field Emission Imaging for Studying the Doping-Dependent Emission Behavior of Silicon Field Emitter Arrays JF - Micromachines N2 - Field emitter arrays (FEAs) are a promising component for novel vacuum micro- and nanoelectronic devices, such as microwave power amplifiers or fast-switching X-ray sources. However, the interrelated mechanisms responsible for FEA degradation and failure are not fully understood. Therefore, we present a measurement method for quantitative observation of individual emission sites during integral operation using a low-cost, commercially available CMOS imaging sensor. The emission and degradation behavior of three differently doped FEAs is investigated in current-regulated operation. The measurements reveal that the limited current of the p-doped emitters leads to an activation of up to 55% of the individual tips in the array, while the activation of the n-type FEA stopped at around 30%. This enhanced activation results in a more continuous and uniform current distribution for the p-type FEA. An analysis of the individual emitter characteristics before and after a constant current measurement provides novel perspectives on degradation behavior. A burn-in process that trims the emitting tips to an integral current-specific ideal field enhancement factor is observed. In this process, blunt tips are sharpened while sharp tips are dulled, resulting in homogenization within the FEA. The methodology is described in detail, making it easily adaptable for other groups to apply in the further development of promising FEAs. Y1 - 2023 U6 - https://doi.org/10.3390/mi14112008 VL - 14 IS - 11 PB - MDPI ER - TY - CHAP A1 - Schels, Andreas A1 - Herdl, Florian A1 - Hausladen, Matthias A1 - Wohlfartsstätter, Dominik A1 - Bachmann, Michael A1 - Edler, Simon A1 - Düsberg, Felix A1 - Pahlke, Andreas A1 - Buchner, Philipp A1 - Schreiner, Rupert A1 - Hansch, Walter T1 - Beta Factor Mapping of Individual Emitting Tips During Integral Operation of Field Emission Arrays T2 - 2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA N2 - Emission uniformity mappings of field emitter arrays provide important insight into degradation mechanisms, but are often laborious, non-integral, costly, or not quantifiable. Here, a low-cost Raspberry Pi HQ camera is used as an extraction anode to quantify the emission distribution in field emitter arrays. A verification measurement using controlled SEM electron beams proves, that current-voltage characteristics of individual emission sites can be determined by combining the integral electrical data with the image data. The characteristics are used to quantify the field enhancement factors of an 30x30 silicon field emitter array during integral operation. Comparison of the field enhancement factor distributions before and after a one-hour constant current operation at 1 µA shows an increase from 50 actively emitting tips before to 156 after the measurement. It is shown, that the distribution of field enhancement factors shifts towards lower values, due to the increasing degradation for high field enhancement tips, especially above 1500. KW - field emission KW - field emission imaging KW - field emission distribution KW - field enhancement factor KW - CMOS imaging KW - beta factor Y1 - 2023 SN - 979-8-3503-0143-4 U6 - https://doi.org/10.1109/IVNC57695.2023.10188957 SP - 224 EP - 226 PB - IEEE ER - TY - CHAP A1 - Herdl, Florian A1 - Kueddelsmann, Maximillian J. A1 - Schels, Andreas A1 - Bachmann, Michael A1 - Edler, Simon A1 - Wohlfartsstätter, Dominik A1 - Düsberg, Felix A1 - Prugger, Alexander A1 - Dillig, Michael A1 - Dams, Florian A1 - Schreiner, Rupert A1 - Coileáin, Cormac Ó. A1 - Zimmermann, Stefan A1 - Pahlke, Andreas A1 - Duesberg, Georg S. T1 - Characterization and Operation of Graphene-Oxide-Semiconductor Emitters at Atmospheric Pressure Levels T2 - 2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA N2 - In recent years Graphene-Oxide-Semiconductor (GOS) electron emitters have attracted a lot of interest due to their outstanding durability in modest vacuum conditions. However, the performance at ambient pressure remains largely unexplored. In this study GOS-emitters are characterized in nitrogen and air at atmospheric pressure, and compared with their vacuum characteristics. For this purpose, lifetime and IV-characteristics measurements are shown. Furthermore, the GOS-emitter was operated as an ionization source for ion mobility spectrometry (IMS) at ambient conditions. KW - durability KW - graphene compounds KW - ion mobility KW - semiconductor-insulator boundaries Y1 - 2023 SN - 979-8-3503-0143-4 U6 - https://doi.org/10.1109/IVNC57695.2023.10188974 SP - 14 EP - 16 PB - IEEE ER - TY - CHAP A1 - Hausladen, Matthias A1 - Buchner, Philipp A1 - Schels, Andreas A1 - Edler, Simon A1 - Bachmann, Michael A1 - Schreiner, Rupert T1 - An Integrated Field Emission Electron Source on a Chip Fabricated by Laser-Micromachining and Mems Technology T2 - 2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA N2 - A silicon field emission electron source consisting of a cathode and a grid electrode has been fabricated by laser micromachining. The cathode features 21×21 tips on an area of 4×4 mm 2 , With a self-aligning MEMS technology for the aperture grid, a high electron transmission (99 %) was achieved. Onset voltages of 50…70 V were observed for an emission current of 1 nA. A stable emission current of 1 mA ± 1.3 % at an extraction voltage of 250 V was observed during a 30-min operation. KW - Apertures KW - Field Emission KW - Field Emission Array KW - Ions KW - Laser-Micromachining KW - Lasers KW - Micromechanical devices KW - Silicon KW - Silicon Field Emission Array KW - Steady-state KW - Vacuum systems Y1 - 2023 SN - 979-8-3503-0143-4 U6 - https://doi.org/10.1109/IVNC57695.2023.10189001 SP - 115 EP - 116 PB - IEEE ER -