@inproceedings{WickLindnerZimmeretal., author = {Wick, Michael and Lindner, Gerhard and Zimmer, Katja and Schreiner, Rupert and Fuhrmann, Thomas and Seebauer, Gudrun and Xu, Boqing and Zheng, Jihong and Wang, Ning}, title = {German-Chinese cooperative Bachelor in engineering physics/optoelectronics}, series = {14th Conference on Education and Training in Optics and Photonics: ETOP 2017; Hangzhou, China 29.05.2017 - 31.05.2017}, booktitle = {14th Conference on Education and Training in Optics and Photonics: ETOP 2017; Hangzhou, China 29.05.2017 - 31.05.2017}, editor = {Liu, Xu and Zhang, Xi-Cheng}, publisher = {SPIE}, isbn = {9781510613812}, doi = {10.1117/12.2269943}, abstract = {The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further.}, language = {en} } @inproceedings{KnappLangerPrommesbergeretal., author = {Knapp, Wolfram and Langer, Christoph and Prommesberger, Christian and Lindner, Matthias and Schreiner, Rupert}, title = {Investigations of the transition from field electron emission to stable plasma discharge in a micro electron source at vacuum pressure}, series = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, booktitle = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, publisher = {IEEE}, doi = {10.1109/IVNC.2017.8051594}, pages = {166 -- 167}, abstract = {We report on the transition from field electron emission to plasma discharges. During an experiment with a miniaturized field emission electron source a plasma discharge accompanied by a luminous effect was observed. A novel graphical evaluation method was used to interpret and to compare the observed phenomenon.}, language = {en} } @article{SchreinerSchweizer, author = {Schreiner, Rupert and Schweizer, Heinz C.}, title = {High-frequency operation of 1.57-μm laterally coupled distributed feedback lasers with self-aligned ohmic contacts and nickel surface gratings}, series = {IEEE Journal of Selected Topics in Quantum Electronics}, volume = {9}, journal = {IEEE Journal of Selected Topics in Quantum Electronics}, number = {5}, publisher = {IEEE}, doi = {10.1109/JSTQE.2003.819469}, pages = {1179 -- 1182}, abstract = {Laterally coupled distributed feedback lasers with self-aligned ohmic contacts show the advantage of a considerably simplified fabrication process. These lasers exhibit superior spectral properties with full benefit from the gain coupling mechanism. Side-mode suppression ratios up to 55- and 3-dB bandwidths beyond 15 GHz were obtained for these devices.}, language = {en} } @article{DamsSchreiner, author = {Dams, Florian and Schreiner, Rupert}, title = {Influencing factors on the sensitivity of MEMS-based thermal conductivity vacuum gauges}, series = {Journal of vacuum science \& technology A}, volume = {32}, journal = {Journal of vacuum science \& technology A}, number = {3}, publisher = {AVS}, doi = {10.1116/1.4867486}, abstract = {The measurement range of thermal conductivity vacuum gauges is mainly influenced by the sensitivity of the sensing element to variations in pressure. An enhanced definition of sensitivity shows its theoretical dependence on the geometric measures of the sensor element at the whole pressure range. This value gives the possibility of direct comparison between different types of sensor structures without the influence of the operating conditions. To study the influencing factors, sensor chips with heated surfaces in the order of some tens of mm 2 were realized by microelectromechanical systems-based fabrication techniques. By a silicon-glass hybrid process two cold planes were formed in a distance of 150 mu m above and below the heated element. The thermal conductance of devices with different geometric measures was determined in constant temperature operating mode by usage of embedded measurement equipment. In this configuration the sensor signals were sensitive to pressure in a region from 10(-5) mbar. The sensitivity was extracted by a fit of the theoretical model to the measurement data and showed the predicted dependencies on the geometric measures. (C) 2014 American Vacuum Society.}, language = {en} } @article{DamsNavitskiPrommesbergeretal., author = {Dams, Florian and Navitski, Aliaksandr and Prommesberger, Christian and Serbun, Pavel and Langer, Christoph and M{\"u}ller, G{\"u}nter and Schreiner, Rupert}, title = {Homogeneous Field Emission Cathodes With Precisely Adjustable Geometry Fabricated by Silicon Technology}, series = {IEEE Transactions on Electron Devices}, volume = {59}, journal = {IEEE Transactions on Electron Devices}, number = {10}, publisher = {IEEE}, issn = {0018-9383}, doi = {10.1109/TED.2012.2206598}, pages = {2832 -- 2837}, abstract = {Silicon-based cathodes with precisely aligned field emitter arrays of sharp tips applicable for miniaturized electron sources were successfully fabricated and characterized. This was made possible by an improved fabrication process using wet thermal oxidation, wet etching, and reactive-ion etching steps with adjustable anisotropy. As substrate materials, both p-doped silicon and n-doped silicon were used. The cathode chips contain about 3 × 10 5 Si tips/cm 2 in a triangular array with tip heights of 2.5 μm, tip radii of less than 30 nm, and spacing of 20 μm. Well-aligned field emission (FE) and excellent homogeneity from all tips (i.e., 100\% efficiency) and maximum stable currents of typically 0.1 μA (0.6 μA) for p (n)-type Si were reproducibly achieved. The current-voltage characteristics of the p-Si tips exhibit the expected saturation at around 10 nA with around ten times better current stability, whereas the n-Si tips show the usual Fowler-Nordheim behavior. Additional coating of the Si tips with 5-nm Cr and 10-nm Au layers resulted in improved stability and at least five times higher average FE current limits (about 3 μA) at about 30\% higher operation voltage.}, language = {en} } @article{TanYeapChowetal., author = {Tan, Pi Lin and Yeap, Guan Yeow and Chow, Wen Shyang and Schreiner, Rupert and Cheong, Kuan Yew}, title = {Effect of Thickness of Porphyrin on Electrical Properties of Organic Devices}, series = {Advanced Materials Research (AMR)}, volume = {1024}, journal = {Advanced Materials Research (AMR)}, publisher = {Trans Tech Publications Ltd.}, address = {Baech}, issn = {1662-8985}, doi = {10.4028/www.scientific.net/AMR.1024.381}, pages = {381 -- 384}, abstract = {The study on electrical properties for both 2,3,7,8,12,13,17,18-octaethyl-21,23H-porphine Cu (II) (Cu-porphyrin) and 2,3,7,8,12,13,17,18-octaethyl-21,23H-porphine (porphyrin) thin film, which were fabricated using spin coating method was conducted. Porphyrins were diluted with chloroform of various concentrations (0.05 mg/ml, 0.1 mg/ml, 0.5 mg/ml, 2.0 mg/ml and 3.0 mg/ml). The solution was spin coated on top of glass substrates. A layer of aluminum was evaporated on top of the organic thin film through thermal evaporation and shadow mask was placed on top of the organic thin film where two electrodes with a gap of 50 μm were formed. Surface morphology of the organic thin film was observed by scanning electron microscope (SEM) and profilometer. Different concentrations of organic solutions greatly affected the molecular packing and arrangement order of the organic thin film and thickness of the organic layer and eventually affected electrical properties of the devices.}, language = {en} } @article{LangerBerndtSchreiner, author = {Langer, Christoph and Berndt, Dominik and Schreiner, Rupert}, title = {Sensitivity of thermal conductivity vacuum gauges for constant current and constant temperature operation}, series = {Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics}, volume = {40}, journal = {Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics}, number = {5}, publisher = {AIP Publishing}, doi = {10.1116/6.0001964}, abstract = {To optimize the measurement range of thermal conductivity vacuum gauges, an expression for the sensitivity is required that takes into account all geometrical, material-specific, and operating parameters. Therefore, equations of the sensor output signal as a function of the pressure for the constant current and the constant temperature mode have been developed analytically. Based on these equations, the sensitivity of the vacuum gauge and its influencing parameters was investigated and discussed. For comparable conditions, the constant temperature operation shows a significantly higher sensitivity for high pressures, while the constant current operation shows higher sensitivity at low pressures. The sensitivity in both the constant current and the constant temperature mode depends on the ratio of the filament surface area and the parasitic thermal conductance. In addition, for the constant current operation, the sensitivity also depends on the current value and the temperature coefficient of the filament resistor. For the constant temperature operation, the sensitivity additionally depends on the distance of the filament and the reference plane. However, to extend the measurement range of a thermal conductivity vacuum gauge toward low pressures, a reduction of the parasitic thermal conductance is mandatory for both the constant current and the constant temperature mode.}, language = {en} } @inproceedings{DamsPrommesbergerSchreiner, author = {Dams, Florian and Prommesberger, Christian and Schreiner, Rupert}, title = {Fabrication process of silicon-tip-arrays for field emission applications}, series = {24th International Vacuum Nanoelectronics Conference (IVNC), 2011 : 18 - 22 July 2011, Historische Stadthalle Wuppertal, Germany}, booktitle = {24th International Vacuum Nanoelectronics Conference (IVNC), 2011 : 18 - 22 July 2011, Historische Stadthalle Wuppertal, Germany}, publisher = {IEEE}, isbn = {978-3-00-035081-8}, issn = {2380-6311}, pages = {49 -- 50}, abstract = {A micromachined process to assemble homogeneous and reproducible tip arrays for field emission applications is developed and characterized. As substrate material p- as well as n-doped silicon is used. Lateral position of the tips is defined by structuring silicon dioxide to discs in a photolithographic process. Vertical structure of the tips is defined by a combination of RIE dry etching with controlled anisotropy and thermally oxidization of silicon in order to sharpen the tips. Hence field emitter arrays (FEAs) can be assembled both as bare and coated cathodes. To assemble field emission diodes, this fabrication process allows placing a metal anode in a micrometer order distance to the tips by a self-aligning procedure. The anode is placed in an evaporation process whereupon sharpening oxide is used as isolator between anode and cathode. Electrical characterization of the cathodes showed very good homogeneity, well alignment and stability over time of emission current from all tips (i.e. 100\% efficiency).}, language = {en} } @inproceedings{SchreinerMulotWiedmannetal., author = {Schreiner, Rupert and Mulot, M. and Wiedmann, J{\"o}rg and Coenning, W. and Porsche, J. and Gentner, Jean-Louis and Berroth, Manfred and Scholz, Ferdinand and Schwizer, H.}, title = {Dynamic measurements on narrow linewidth complex coupled 1.55 μm DFB lasers with gain and index grating in antiphase}, series = {Conference Proceedings. Eleventh International Conference on Indium Phosphide and Related Materials (IPRM'99), 16-20 May 1999, Davos, Switzerland}, booktitle = {Conference Proceedings. Eleventh International Conference on Indium Phosphide and Related Materials (IPRM'99), 16-20 May 1999, Davos, Switzerland}, publisher = {IEEE}, address = {Piscataway}, isbn = {0-7803-5562-8}, doi = {10.1109/ICIPRM.1999.773626}, pages = {25 -- 28}, abstract = {We report on dynamic measurements on antiphase complex coupled 1.55 /spl mu/m DFB lasers. The antiphase complex coupling mechanism is realized by periodically etching the active layer and quarternary InGaAsP overgrowth. This new fabrication approach results in very narrow linewidths measured on devices with rather short resonator lengths. The minimum linewidth for a 375 /spl mu/m long ridge waveguide laser was only 250 kHz at an optical output power of 4 mW. The RC-limited 3dB-bandwidth for those devices was /spl sim/6 GHz. Using circuit model corrections, the intrinsic bandwidth limitation of those lasers was found to be 17.4 GHz.}, language = {en} } @inproceedings{SchreinerNaegeleKoerbletal., author = {Schreiner, Rupert and Naegele, Peter and Koerbl, Michael and Groening, Albert and Gentner, Jean-Louis and Schweizer, Heinz C.}, title = {Monolithically integrated tunable laterally-coupled distributed feedback lasers with self-aligned Ti/Pt/Au ohmic contacts}, series = {Proceedings Volume 4871, Semiconductor Lasers and Optical Amplifiers for Lightwave Communication SystemsSemiconductor Lasers and Optical Amplifiers for Lightwave Communication Systems}, booktitle = {Proceedings Volume 4871, Semiconductor Lasers and Optical Amplifiers for Lightwave Communication SystemsSemiconductor Lasers and Optical Amplifiers for Lightwave Communication Systems}, editor = {Mirin, Richard P. and Menoni, Carmen S.}, publisher = {SPIE}, doi = {10.1117/12.457281}, pages = {160}, abstract = {We present a new method for fabrication of tunable InGaAsP-InP single mode lasers without epitaxial overgrowth. These devices show the advantage of a considerably simplified fabrication process compared to conventional tunable laser types. The lasers comprise an active Bragg reflector integrated with an uncorrugated separately pumped gain region. To overcome the extensive and expensive overgrowth step we realized a surface grating on both sides of the ridge mesa, which provides DFB operation. By adjusting the current through the Bragg reflector, the wavelength can be tuned between 1590.8 nm and 1595.2 nm. A maximum of 11 wavelength channels with an average spacing of ~0.5 nm and a constant optical output power of ~0.5 mW are addressable.}, language = {en} } @article{CheongAwKarimovetal., author = {Cheong, Kuan Yew and Aw, Kean and Karimov, Khasan S. and Zhao, Feng and Mahroof-Tahir, Mohammad and Schreiner, Rupert}, title = {Advances in Smart Materials and Applications}, series = {Advances in Materials Science and Engineering}, journal = {Advances in Materials Science and Engineering}, publisher = {Hindawi}, doi = {10.1155/2014/517342}, abstract = {This is one of a series of special issues published in Advances in Materials Science and Engineering, focusing on the latest advances of smart materials and their applications. Evolution of engineering materials is strongly depending on the growing transformation of complexity in engineering products. New materials being designed are required to provide specific properties and demonstrate certain functional characteristics by manipulating their dimension, chemistry, and structure through various advanced technologies. Therefore, "smartness" of a material has become the topic of interest. Properties of smart materials may change accordingly to the applied external stimuli. Under the direction of the editorial team, we showcase advances of organic and inorganic based smart materials and their applications in areas of specific interest such as energy, environment, and health. A total of 9 articles are published in this special issue. Six articles are focused on production, synthesis, and optimization of smart materials; and the remaining are dedicated to application of smart materials.}, language = {en} } @inproceedings{SaravananGerlachPeschkeetal., author = {Saravanan, Brem Kumar and Gerlach, Philipp and Peschke, Martin and Knoedl, Thomas and Schreiner, Rupert and Hanke, Christian and Stegmueller, Bernhard}, title = {Integrated DFB laser electro-absorption modulator based on identical MQW-double stack active layer for high-speed modulation beyond 10 GBIT/S}, series = {16th IPRM. 2004 International Conference on Indium Phosphide and Related Materials, 31 May - 04 June 2004, Kagoshima, Japan}, booktitle = {16th IPRM. 2004 International Conference on Indium Phosphide and Related Materials, 31 May - 04 June 2004, Kagoshima, Japan}, publisher = {IEEE}, isbn = {0-7803-8595-0}, doi = {10.1109/ICIPRM.2004.1442656}, pages = {236 -- 238}, abstract = {Integrated DFBLD-EAM-SOA devices utilizing an identical MQW active region have been realized in the AlGaInAs/InP material system. A fiber-coupled optical power of >6 mW with a 10 dB static extinction, 44 dB SMSR single-mode spectrum and a 3 dBe cutoff frequency of 25 GHz was measured.}, language = {en} } @article{ZahnerSchreinerStierstorferetal., author = {Zahner, Th and Schreiner, Rupert and Stierstorfer, R. and Kus, O. and Li, S. T. and Roessler, R. and Pedarnig, J. D. and B{\"a}uerle, D. and Lengfellner, H.}, title = {Off-diagonal Seebeck effect and anisotropic thermopower in Bi2Sr2CaCu2O8 thin films}, series = {Europhysics Letters}, volume = {40}, journal = {Europhysics Letters}, number = {6}, publisher = {IOP Sciences}, doi = {10.1209/epl/i1997-00521-4}, pages = {673 -- 678}, abstract = {The anisotropy ΔS of the thermopower in thin films of the high-Tc superconductor Bi2Sr2CaCu2O8 is investigated using off-c-axis epitaxial film growth and the off-diagonal Seebeck effect. The measurements represent a new method for the investigation of anisotropic transport properties in solids, taking advantage of the availability of oriented grown crystalline thin films instead of using bulk crystals. First results for the temperature dependence ΔS(T) in Bi2Sr2CaCu2O8 thin films are presented and described within a two-band model. Subjecting the films to heat treatments in different gases at relatively low temperatures, ΔS could reversibly be changed in a wide range.}, language = {en} } @inproceedings{KnodlHankeSaravananetal., author = {Knodl, Thomas and Hanke, Christian and Saravanan, Brem Kumar and Peschke, Martin and Schreiner, Rupert and Stegmuller, Bernhard}, title = {Integrated 1.3-μm InGaAlAs-InP laser-modulator with double-stack MQW layer structure}, series = {Proceedings Volume 5451, Integrated Optics and Photonic Integrated Circuits}, booktitle = {Proceedings Volume 5451, Integrated Optics and Photonic Integrated Circuits}, editor = {Righini, Giancarlo C. and Honkanen, Seppo}, publisher = {SPIE}, doi = {10.1117/12.544610}, pages = {1}, abstract = {We present first experimental results of the successful transfer of our monolithic integrated double-stack multi quantum well laser-modulator approach from the traditional InGaAsP/InP to the more promising InGaAlAs/InP material system. In continuous wave operation at room temperature, the devices achieved threshold currents of <21 mA, fiber coupled optical power levels up to 570 μW and static extinction ratios in the range of 15 dB/V. The measured small-signal modulation bandwidth of about 10 GHz is capacitance limited due to a conservative device layout.}, language = {en} } @inproceedings{SchreinerGrabeldingerWiedmannetal., author = {Schreiner, Rupert and Grabeldinger, H. and Wiedmann, J. and Wunstel, K. and Porsche, J. and Scholz, Ferdinand and Schweizer, H.}, title = {Complex coupled 1.55 mu m tunable super-grating DFB lasers and photonic filters}, series = {Compound semiconductors 1999 : proceedings of the Twenty-Sixth International Symposium on Compound Semiconductors held in Berlin, Germany, 22 - 26 August 1999}, booktitle = {Compound semiconductors 1999 : proceedings of the Twenty-Sixth International Symposium on Compound Semiconductors held in Berlin, Germany, 22 - 26 August 1999}, publisher = {Inst. of Physics Publ.}, address = {Bristol [u.a.]}, isbn = {0-7503-0704-8}, abstract = {We report on the investigation and realization of photonic filters based on the combination of fractional compositions of a few basic grating periods. Using a minimum set of two basic periods Lambda(1) and Lambda(2) we demonstrate comb-like few mode photonic band gap structures with arbitrary numbers of bands and frequency spacing between the bands. Optically integrated filters of different comb periods result in switchable wavelength filters for channel selection in WDM applications.}, language = {en} } @inproceedings{SchreinerSchweizer, author = {Schreiner, Rupert and Schweizer, Heinz C.}, title = {High frequency operation of 1.57 μm laterally gain coupled DFB lasers with self aligned ohmic contacts and nickel surface gratings}, series = {IEEE 18th International Semiconductor Laser Conference; 29 Sept.-3 Oct. 2002, Garmisch, Germany}, booktitle = {IEEE 18th International Semiconductor Laser Conference; 29 Sept.-3 Oct. 2002, Garmisch, Germany}, publisher = {IEEE}, isbn = {0-7803-7598-X}, doi = {10.1109/ISLC.2002.1041099}, pages = {21 -- 22}, abstract = {Laterally coupled DFB lasers with self-aligned ohmic contacts show the advantage of a, considerably simplified fabrication process. Side-mode-suppresion-ratios up to 55 dB and 3 dB-bandwidths beyond 15 GHz were obtained for these devices.}, language = {en} } @inproceedings{PodstranskyHausladenZlamaletal., author = {Podstr{\´a}nsk{\´y}, J{\´a}chym and Hausladen, Matthias and Zl{\´a}mal, Jakub and Kn{\´a}pek, Alexandr and Schreiner, Rupert}, title = {Single Column Multiple Electron Beam Imaging from N-Type Silicon}, series = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, booktitle = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, publisher = {IEEE}, isbn = {979-8-3503-7976-1}, doi = {10.1109/IVNC63480.2024.10652470}, pages = {1 -- 2}, abstract = {This work is aimed at measuring the electron emission from multiple cathodes formed by n-doped silicon and imaging the electron beams focused by an einzel lens on a CMOS camera. The experimental results are compared with computer simulation to understand the electron emission from the semiconductor cathode and the observed imaging imperfections. Finally, modifications to the experimental setup are suggested that should lead to improvement in the extraction current and spot size of focused electron beams and also better understanding of the processes taking place in the experiment.}, language = {en} } @article{SchmidtDenkerDashielletal., author = {Schmidt, Oliver G. and Denker, Ullrich and Dashiell, Michael W. and Jin-Phillipp, Neng Yun and Eberl, Karl and Schreiner, Rupert and Gr{\"a}beldinger, Hedwig and Schweizer, Heinz C. and Christiansen, Silke H. and Ernst, Frank}, title = {Laterally aligned Ge/Si islands: a new concept for faster field-effect transistors}, series = {Materials Science and Engineering B}, volume = {89}, journal = {Materials Science and Engineering B}, number = {1-3}, publisher = {Elsevier}, address = {New York, NY}, issn = {1873-4944}, doi = {10.1016/S0921-5107(01)00810-8}, pages = {101 -- 105}, abstract = {Self-assembled and coherently strained Ge dots were grown on a Si/SiGe superlattice, which was deposited on a flat Si(001) substrate surface patterned with a regular array of straight trenches. The superlattice translates the surface modulation of the substrate into a strain-field modulation, which causes the Ge dots on its surface to form along straight lines above the buried trenches. This approach provides self-assembled Ge dots with excellent lateral periodicity, which might be useful for fabricating dot-based field-effect-transistors (DotFETs). Here, we propose the concept of a modulation-doped p-channel DotFET (p-MOD-DotFET). The p-MOD-DotFET relies on embedded Ge-rich nanostructures, which provide p-channels through the Ge-rich dots. A high Ge concentration in the dots is desirable in order to exploit the high hole mobility of Ge-rich material. We show that the commonly observed Si-Ge intermixing during Si capping of Ge dots can be suppressed by overgrowing the islands at low temperature.}, language = {en} } @inproceedings{EilerHoeglLindneretal., author = {Eiler, Julian and H{\"o}gl, Christina and Lindner, Matthias and Bachmann, Michael and Schreiner, Rupert}, title = {Miniaturized Surface Dielectric Barrier Discharge Plasma Actuators for Application in Chemical Analysis Systems}, series = {2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA}, booktitle = {2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA}, publisher = {IEEE}, isbn = {979-8-3503-0143-4}, doi = {10.1109/IVNC57695.2023.10188884}, pages = {40 -- 42}, abstract = {A new concept for a miniaturized planar ion source based on a surface dielectric barrier discharge (SDBD) is presented. A fabrication method based on a stamping process is described, and the plasma actuators are characterized based on their power in dependence of the applied voltage. The voltage for plasma ignition is approx. 1 kV with a maximum plasma power of 40 W/m at 3,4 kV.}, language = {en} } @inproceedings{BartlBuchnerHausladenetal., author = {Bartl, Mathias and Buchner, Philipp and Hausladen, Matthias and Asgharzadehkhorasani, Ali and Bachmann, Michael and Schreiner, Rupert}, title = {Simulations and Investigations of Silicon Nanowire Field Emitters}, series = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, booktitle = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, publisher = {IEEE}, doi = {10.1109/IVNC63480.2024.10652355}, pages = {1 -- 2}, abstract = {The emission behavior of field emission electron sources consisting of a silicon nanowire cathode, an extraction grid electrode and a planar anode was investigated based on a particle tracing simulation using FEM. The focus was on the influence of the grid geometry as well as the positioning of the grid relative to the emitters on the electron transmission. The highest transmission can be achieved with the emitter tips protruding 10 µm trough the extraction grid openings. The transmission decreases more rapidly with increasing distance between the tip and the grid the thicker the grid is.}, language = {en} } @article{HausladenBuchnerBartletal., author = {Hausladen, Matthias and Buchner, Philipp and Bartl, Mathias and Bachmann, Michael and Schreiner, Rupert}, title = {Integrated multichip field emission electron source fabricated by laser-micromachining and MEMS technology}, series = {Journal of Vacuum Science \& Technology B}, volume = {42}, journal = {Journal of Vacuum Science \& Technology B}, number = {1}, publisher = {AIP Publishing}, doi = {10.1116/6.0003233}, abstract = {In this work, high-current field emission electron source chips were fabricated using laser-micromachining and MEMS technology. The resulting chips were combined with commercially available printed circuit boards (PCBs) to obtain a multichip electron source. By controlling the separate electron sources using an external current control circuit, we were able to divide the desired total current evenly across the individual chips deployed in the PCB-carrier. In consequence, we were able to show a decreased degradation due to the reduced current load per chip. First, a single electron source chip was measured without current regulation. A steady-state emission current of 1 mA with a high stability of ±1.3\% at an extraction voltage of 250 V was observed. At this current level, a mean degradation slope of -0.7 μA/min with a nearly perfect transmission ratio of 99\% ± 0.4\% was determined. The measurements of a fully assembled multichip PCB-carrier electron source, using a current control circuit for regulation, showed that an even distribution of the desired total current led to a decreased degradation. This was determined by the increase in the required extraction voltage over time. For this purpose, two current levels were applied to the electron source chips of the PCB-carrier using an external current control circuit. First, 300 μA total current was evenly distributed among the individual electron source chips followed by the emission of 300 μA per electron source chip. This allows the observation of the influence of a distributed and nondistributed total current, carried by the electron source chips. Thereby, we obtained an increase in the mean degradation slope from +0.011 V/min (300 μA distributed) to +0.239 V/min (300 μA per chip), which is approximately 21 times higher. Moreover, our current control circuit improved the current stability to under 0.1\% for both current levels, 300 μA distributed and 300 μA per chip.}, language = {en} } @article{RemškarJelencCzepurnyietal., author = {Remškar, Maja and Jelenc, Janez and Czepurnyi, Nikolai and Malok, Matjaž and Pirker, Luka and Schreiner, Rupert and H{\"u}ttel, Andreas K.}, title = {Modulations of the work function and morphology of a single MoS2 nanotube by charge injection}, series = {Nanoscale Advances}, journal = {Nanoscale Advances}, publisher = {Royal Society of Chemistry (RSC)}, issn = {2516-0230}, doi = {10.1039/d4na00490f}, abstract = {Both the miniaturization of transistor components and the ongoing investigation of material systems with potential for quantum information processing have significantly increased current interest of researchers in semiconducting inorganic nanotubes. Here we report on an additional outstanding aspect of these nanostructures, namely the intrinsic coupling of electronic and mechanical properties. We observe electronic and morphology changes in a single MoS2 nanotube, exposed to charge injections by means of an atomic-force-microscopy tip. An elliptic deformation of the nanotube and helical twisting of the nanotube are visible, consistent with the reverse piezoelectric effect. Work-function changes are found to be dependent on the polarity of the injected carriers. An unexpected long-term persistence of the shape deformations is observed and explained with accumulation of structural defects and the resultant strain, which could cause a memory-like charge confinement and a long lasting modulation of the work function.}, language = {en} }