@misc{SchwartzKlossekKittleretal., author = {Schwartz, Bernhard and Klossek, Andre and Kittler, Martin and Oehme, Michael and Kasper, Erich and Schulze, J{\"o}rg}, title = {Electroluminescence of Germanium-LEDs on Silicon}, series = {Physica Status Solidi C}, volume = {11}, journal = {Physica Status Solidi C}, number = {11-12}, doi = {10.1002/pssc.201400056}, pages = {1686 -- 1691}, language = {en} } @misc{OehmeWidmannKosteckietal., author = {Oehme, Michael and Widmann, Daniel and Kostecki, Konrad and Zaumseil, Peter and Schwartz, Bernhard and Gollhofer, Martin and K{\"o}rner, Roman and Bechler, Stefan and Kittler, Martin and Kasper, Erich and Schulze, J{\"o}rg}, title = {GeSn/Ge Multi Quantum Well Photodetectors on Si Substrates}, series = {Optics Letters}, volume = {39}, journal = {Optics Letters}, number = {16}, issn = {1539-4794}, doi = {10.1364/OL.39.004711}, pages = {4711 -- 4714}, language = {en} } @misc{SchwartzSaringArguirovetal., author = {Schwartz, Bernhard and Saring, Philipp and Arguirov, Tzanimir V. and Oehme, Michael and Kostecki, Konrad and Kasper, Erich and Schulze, J. and Kittler, Martin}, title = {Analysis of EL Emitted by LEDs on Si Substrates Containing GeSn/Ge Multi Quantum Wells as Active Layers}, series = {Solid State Phenomena}, volume = {242}, journal = {Solid State Phenomena}, issn = {1012-0394}, doi = {10.4028/www.scientific.net/SSP.242.361}, pages = {361 -- 367}, language = {en} } @misc{SchwartzReicheKittler, author = {Schwartz, Bernhard and Reiche, Manfred and Kittler, Martin}, title = {Influence of strain, donor concentration, carrier confinement, and dislocation density on the efficiency of luminiscence of Ge-based structures on Si substrate}, series = {Physica Status Solidi : C, Current Topics in Solid State Physics}, volume = {14}, journal = {Physica Status Solidi : C, Current Topics in Solid State Physics}, number = {7}, issn = {1610-1642}, pages = {1700018-1 -- 1700018-5}, language = {en} } @misc{KittlerReicheSchwartzetal., author = {Kittler, Martin and Reiche, Manfred and Schwartz, Bernhard and Uebensee, Hartmut and Kosina, Hans and Stanojevic, Zlatan and Baumgartner, Oskar and Ortlepp, Thomas}, title = {Transport of Charge Carriers along Dislocations in Si and Ge}, series = {Physica status solidi. A, Applications and materials science}, volume = {Volume 216}, journal = {Physica status solidi. A, Applications and materials science}, number = {17}, issn = {1862-6319}, doi = {10.10002/pssa.201900287}, pages = {7}, abstract = {Experimental observations and quantum mechanical device simulations point to different electronic properties of dislocations in silicon and germanium. The experimental data suggest a supermetallic behavior of the dislocations in Si and thus the high strain in the dislocation core is thought to cause the confinement of the charge carriers, which leads to the formation of a 1D electron gas along a dislocation (quantum wire). The resulting significant increase in the electron concentration corresponds to a marked increase in the drain current of metal-oxide-semiconductor field-effect transistor (MOSFET). The specific resistance of an individual dislocation in Ge is about nine orders of magnitude higher than for a dislocation in Si. The experimental measurements of the strain in dislocation cores in Ge are still missing. Based on the band structure data, the generation of a strain equivalent to that of the dislocation cores in Si appears to be very challenging because of the transition from an indirect into a direct semiconductor with about tenfold lower strain levels. The lower strain in the dislocation core in germanium may not support the carrier confinement as proposed for the dislocation core of silicon, and consequently 1D electron gases are not expected to form along the dislocations in Ge.}, language = {en} } @inproceedings{SchwartzOehmeKoerneretal., author = {Schwartz, Bernhard and Oehme, Michael and K{\"o}rner, Roman and Bechler, Stefan and Schulze, J{\"o}rg and Kittler, Martin}, title = {Luminescence of strained Ge on GeSn virtual substrate grown on Si (001)}, series = {Silicon Photonics XII, 30 January-1 February 2017, San Francisco, California, United States}, booktitle = {Silicon Photonics XII, 30 January-1 February 2017, San Francisco, California, United States}, publisher = {SPIE}, address = {Bellingham, Washington}, isbn = {978-1-5106-0657-9}, doi = {10.1117/12.2249564}, pages = {7}, language = {en} } @phdthesis{Schwartz, author = {Schwartz, Bernhard}, title = {Germanium-Laser f{\"u}r die Silizium-Photonik}, doi = {10.26127/BTUOpen-4864}, pages = {120}, language = {de} } @misc{WendavFischerVirgilioetal., author = {Wendav, Torsten and Fischer, Inga Anita and Virgilio, Michele and Capellini, Giovanni and Oliveira, F. and Cerqueira, M. F. and Benedetti, A. and Chiussi, Stefano and Zaumseil, Peter and Schwartz, Bernhard and Busch, Kurt and Schulze, J.}, title = {Photoluminescence from ultrathin Ge-rich multiple quantum wells observed up to room temperature: Experiments and modeling}, series = {Physical Review B 94}, volume = {94}, journal = {Physical Review B 94}, number = {24}, doi = {10.1103/PhysRevB.94.245304}, pages = {245304}, language = {en} } @misc{SchwartzReicheKittler, author = {Schwartz, Bernhard and Reiche, Manfred and Kittler, Martin}, title = {Temperature dependence of luminescence from dislocated Ge on Si substrate}, series = {Materials Today: Proceedings}, volume = {5}, journal = {Materials Today: Proceedings}, number = {3,1}, issn = {2214-7853}, doi = {10.1016/j.matpr.2018.03.061}, pages = {14712 -- 14721}, abstract = {For mono-crystalline Ge the indirect luminescence intensity declines upon growing temperature from 80 to 300 K, whereas for dislocated Ge structures the opposite behavior occurs. These findings are comparable to earlier observations on Si. The drop of the luminescence in dislocated material upon lowering temperature was attributed to the increase of the competing non-radiative recombination due to shallow dislocation states. In opposition to the indirect luminescence, the character of the direct Ge luminescence, i.e. incline of intensity upon growing temperature, is not converted by dislocations. The measured behavior of the direct peak position of Ge, in the temperature range between 80 and 300 K, is in accordance with calculated dependence and reflects the direct bandgap energy. The observed red shifts in dislocated Ge structures are shown to be produced by tensile strain, bandgap narrowing and by the Sn-content of GeSn quantum wells, respectively. A direct influence of dislocations could not be observed. Satisfying understanding of the existing temperature behavior of the indirect Ge peak position is on embryonic stage}, language = {en} } @misc{SchwartzArguirovKittleretal., author = {Schwartz, Bernhard and Arguirov, Tzanimir V. and Kittler, Martin and Oehme, Michael and Kostecki, Konrad and Kasper, Erich and Schulze, J{\"o}rg}, title = {Comparison of EL emitted by LEDs on Si substrates containing Ge and Ge/GeSn MQW as active layers}, series = {Silicon Photonics X, 9-12 February 2015, San Francisco, California, United States}, journal = {Silicon Photonics X, 9-12 February 2015, San Francisco, California, United States}, publisher = {International Society for Optics and Photonics}, doi = {10.1117/12.2080816}, language = {en} } @misc{SchwartzOehmeKosteckietal., author = {Schwartz, Bernhard and Oehme, Michael and Kostecki, Konrad and Widmann, Daniel and Gollhofer, Martin and K{\"o}rner, Roman and Bechler, Stefan and Fischer, Inga Anita and Wendav, Torsten and Kasper, Erich and Schulze, J{\"o}rg and Kittler, Martin}, title = {Electroluminescence of GeSn/Ge MQW LEDs on Si substrate}, series = {Optics Letters}, volume = {40}, journal = {Optics Letters}, number = {13}, doi = {10.1364/OL40.003209}, pages = {3209 -- 3212}, language = {en} } @misc{KoernerSchwarzFischeretal., author = {K{\"o}rner, Roman and Schwarz, Daniel and Fischer, Inga Anita and Augel, Lion and Bechler, Stefan and H{\"a}nel, Linda A. and Kern, Michael and Oehme, Michael and Rolseth, Erlend Granbo and Schwartz, Bernhard and Weißhaupt, David and Zhang, Wogong and Schulze, J{\"o}rg}, title = {The Zener-Emitter: A Novel Superluminescent Ge Optical Waveguide-Amplifier with 4.7 dB Gain at 92 mA Based on Free-Carrier Modulation by Drect Zener Tunneling Monolithically Integrated on Si}, series = {2016 IEEE International Electronic Devices Meeting (IEDM), 3-7 Dec. 2016}, journal = {2016 IEEE International Electronic Devices Meeting (IEDM), 3-7 Dec. 2016}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-5090-3901-2}, pages = {22.5.1 -- 22.5.4}, language = {en} }