@misc{KrauseBeleniotisBengtssonetal., author = {Krause, Sascha and Beleniotis, Petros and Bengtsson, Olof and Rudolph, Matthias and Heinrich, Wolfgang}, title = {Characterization of the Impairment and Recovery of GaN-HEMTs in Low-Noise Amplifiers under Input Overdrive}, series = {2021 IEEE MTT-S International Microwave Symposium (IMS), 07-25 June 2021, Atlanta, GA, USA}, journal = {2021 IEEE MTT-S International Microwave Symposium (IMS), 07-25 June 2021, Atlanta, GA, USA}, isbn = {978-1-6654-0307-8}, issn = {2576-7216}, doi = {10.1109/IMS19712.2021.9574839}, pages = {515 -- 518}, language = {en} } @misc{BeleniotisSchniederRudolph, author = {Beleniotis, Petros and Schnieder, Frank and Rudolph, Matthias}, title = {Simulating Drain Lag of GaN HEMTs with physics-based ASM Model}, series = {2020 15th European Microwave Integrated Circuits Conference (EuMIC), 10-15 January 2021, Utrecht, Netherlands}, journal = {2020 15th European Microwave Integrated Circuits Conference (EuMIC), 10-15 January 2021, Utrecht, Netherlands}, isbn = {978-2-87487-060-6}, pages = {165 -- 168}, language = {en} } @misc{BeleniotisChevtchenkoRudolph, author = {Beleniotis, Petros and Chevtchenko, Serguei A. and Rudolph, Matthias}, title = {Statistical Medeling of GaN HEMTs by Direct Transfer of Veriations to Model Parameters}, series = {16th European Microwave Integrated Circuits Conference (EuMIC), 03-04 April 2022, London, United Kingdom}, journal = {16th European Microwave Integrated Circuits Conference (EuMIC), 03-04 April 2022, London, United Kingdom}, isbn = {978-2-87487-064-4}, doi = {10.23919/EuMIC50153.2022.9783780}, pages = {63 -- 66}, language = {en} } @misc{KrauseZervosBeleniotisetal., author = {Krause, Sascha and Zervos, Christos and Beleniotis, Petros and Ritter, Dan and Rudolph, Matthias and Heinrich, Wolfgang}, title = {On the Influence of Transistor Dimensions on the Dispersive Behavior in A1GaN/GaN HEMT-Based PAs and Robust LNAs}, series = {IEEE/MTT-S International Microwave Symposium - IMS 2022, 19-24 June 2022 Denver, CO, USA}, journal = {IEEE/MTT-S International Microwave Symposium - IMS 2022, 19-24 June 2022 Denver, CO, USA}, publisher = {IEEE}, address = {Piscataway}, isbn = {978-1-6654-9613-1}, doi = {10.1109/IMS37962.2022.9865474}, pages = {914 -- 917}, language = {en} } @misc{BeleniotisSchniederKrauseetal., author = {Beleniotis, Petros and Schnieder, Frank and Krause, Sascha and Haque, Sanaul and Rudolph, Matthias}, title = {An efficient drain-lag model for microwave GaN HEMTs based on ASM-HEMT}, series = {International Journal of Microwave and Wireless Technologie}, volume = {14}, journal = {International Journal of Microwave and Wireless Technologie}, number = {2}, issn = {1759-0795}, doi = {10.1017/S1759078721001483}, pages = {134 -- 142}, language = {en} } @misc{ZervosBeleniotisRudolph, author = {Zervos, Christos and Beleniotis, Petros and Rudolph, Matthias}, title = {Prediction of the large-signal GaN HEMT performance using accurate TCAD-compact modeling method}, series = {2024 19th European Microwave Integrated Circuits Conference (EuMIC)}, journal = {2024 19th European Microwave Integrated Circuits Conference (EuMIC)}, publisher = {IEEE}, doi = {10.23919/EuMIC61603.2024.10732230}, pages = {186 -- 189}, language = {en} } @misc{ZervosBeleniotisRudolph, author = {Zervos, Christos and Beleniotis, Petros and Rudolph, Matthias}, title = {A computational analysis of the impact of thin undoped channels in surface-related current collapse of AlGaN/GaN HEMTs}, series = {Semiconductor Science and Technology}, volume = {39}, journal = {Semiconductor Science and Technology}, number = {9}, publisher = {IOP Publishing}, issn = {0268-1242}, doi = {10.1088/1361-6641/ad689c}, pages = {1 -- 8}, abstract = {Abstract This study provides an insight into the impact of thin purely undoped GaN channel thickness (t ch) on surface-related trapping effects in AlGaN/GaN high electron mobility transistors. Our TCAD study suggests that in cases where parasitic gate leakage is the driving trapping mechanism that promotes the injection of electrons from the Schottky gate contact into surface states, this effect can be alleviated by reducing t ch of the undoped GaN channel. We show that by decreasing t ch from 130 to 10 nm, devices exhibit a reduction in gate-related current collapse under the specific class-B RF operating bias conditions as a consequence of a substantial decrease in the off-state gate leakage with reducing t ch. Large-signal simulations revealed an increase by 3 W mm-1 and about 12\% output power and power-added efficiency due to the decrease of gate-related collapse. This work, for the first time, highlights the role of a proper purely undoped GaN t ch selection to alleviate gate-related surface trapping in the design of GaN-based microwave power amplifiers.}, language = {en} } @misc{BeleniotisKrauseZervosetal., author = {Beleniotis, Petros and Krause, Sascha and Zervos, Christos and Rudolph, Matthias}, title = {A Physics-Based Model for Slow Gate-Induced Electron Trapping in GaN HEMTs}, series = {IEEE Transactions on Electron Devices}, volume = {71}, journal = {IEEE Transactions on Electron Devices}, number = {7}, publisher = {Institute of Electrical and Electronics Engineers (IEEE)}, issn = {0018-9383}, doi = {10.1109/TED.2024.3397234}, pages = {4058 -- 4065}, language = {en} } @misc{BeleniotisZervosKrauseetal., author = {Beleniotis, Petros and Zervos, Christos and Krause, Sascha and Chevtchenko, Serguei and Ritter, Dan and Rudolph, Matthias}, title = {Investigation of traps impact on PAE and linearity of AlGaN/GaN HEMTs relying on a combined TCAD-compact model approach}, series = {IEEE Transactions on Electron Devices}, volume = {71 (2024)}, journal = {IEEE Transactions on Electron Devices}, number = {6}, publisher = {Institute of Electrical and Electronics Engineers (IEEE)}, issn = {0018-9383}, doi = {10.1109/TED.2024.3388386}, pages = {3582 -- 3589}, language = {en} } @misc{YazdaniZervosBeleniotisetal., author = {Yazdani, Hossein and Zervos, Christos and Beleniotis, Petros and Brusaterra, Enrico and Hilt, Oliver and Rudolph, Matthias and W{\"u}rfl, Joachim}, title = {Importance of Scaling in RF GaN HEMTs for Reduction of Surface Traps-Induced Drain Lag}, series = {Physica Status Solidi (a)}, journal = {Physica Status Solidi (a)}, publisher = {Wiley}, issn = {1862-6300}, doi = {10.1002/pssa.202300885}, pages = {1 -- 8}, abstract = {Drain lag is a well-known phenomenon that leads to radio frequency performance degradation in AlGaN/GaN high-electron-mobility transistors. Herein, it is demonstrated that a reduction of the gate-to-drain distance (Lgd) from 2.0 to 0.5 μm results in 7\% reduction in the current collapse. This improvement is attributed to a decrease in surface trapping, which, in this case, is found to have a greater impact on current collapse than relatively slow traps in the buffer layer. To support this argument, TCAD simulations are conducted. Load-pull analysis confirms that scaling the devices to Lgd = 0.5 μm provides 15\% better output power density at 10 GHz than Lgd = 2.0 μm. Additionally, a new passivation layer for reduced surface traps exhibits a 20 to 30\% higher output power density and at least a 10\% improvement in power-added efficiency at 20 GHz on a nominally identical GaN-on-semi-insulating SiC epi-wafer.}, language = {en} }