The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform
F. Nakamura - One of the best experts on this subject based on the ideXlab platform.
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Enhancement‐mode AlGaN/GaN HEMTs with thin InGaN cap layer
Physica Status Solidi (c), 2008Co-Authors: M. Ito, Shigeru Kishimoto, F. Nakamura, Takashi MizutaniAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer has been proposed to implement the normally-off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised leading to the normally- off operation. Fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally-off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm forthe device with a 1.9-μm-long gate. By etching-off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance. The transconductance was increased from 130 to 145 mS/mm by annealing the devices at 250 °C for 20 minutes in a N2 atmosphere. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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AlGaN/GaN HEMTs With Thin InGaN Cap Layer for Normally Off Operation
IEEE Electron Device Letters, 2007Co-Authors: Takashi Mizutani, M. Ito, Shigeru Kishimoto, F. NakamuraAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer have been proposed to implement the normally off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised, which leads to the normally off operation. The fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm for the device with a 1.9-mum-long gate. By etching off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance.
Takashi Mizutani - One of the best experts on this subject based on the ideXlab platform.
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Enhancement‐mode AlGaN/GaN HEMTs with thin InGaN cap layer
Physica Status Solidi (c), 2008Co-Authors: M. Ito, Shigeru Kishimoto, F. Nakamura, Takashi MizutaniAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer has been proposed to implement the normally-off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised leading to the normally- off operation. Fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally-off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm forthe device with a 1.9-μm-long gate. By etching-off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance. The transconductance was increased from 130 to 145 mS/mm by annealing the devices at 250 °C for 20 minutes in a N2 atmosphere. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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AlGaN/GaN HEMTs With Thin InGaN Cap Layer for Normally Off Operation
IEEE Electron Device Letters, 2007Co-Authors: Takashi Mizutani, M. Ito, Shigeru Kishimoto, F. NakamuraAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer have been proposed to implement the normally off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised, which leads to the normally off operation. The fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm for the device with a 1.9-mum-long gate. By etching off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance.
M. Ito - One of the best experts on this subject based on the ideXlab platform.
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Enhancement‐mode AlGaN/GaN HEMTs with thin InGaN cap layer
Physica Status Solidi (c), 2008Co-Authors: M. Ito, Shigeru Kishimoto, F. Nakamura, Takashi MizutaniAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer has been proposed to implement the normally-off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised leading to the normally- off operation. Fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally-off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm forthe device with a 1.9-μm-long gate. By etching-off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance. The transconductance was increased from 130 to 145 mS/mm by annealing the devices at 250 °C for 20 minutes in a N2 atmosphere. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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AlGaN/GaN HEMTs With Thin InGaN Cap Layer for Normally Off Operation
IEEE Electron Device Letters, 2007Co-Authors: Takashi Mizutani, M. Ito, Shigeru Kishimoto, F. NakamuraAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer have been proposed to implement the normally off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised, which leads to the normally off operation. The fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm for the device with a 1.9-mum-long gate. By etching off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance.
Shigeru Kishimoto - One of the best experts on this subject based on the ideXlab platform.
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Enhancement‐mode AlGaN/GaN HEMTs with thin InGaN cap layer
Physica Status Solidi (c), 2008Co-Authors: M. Ito, Shigeru Kishimoto, F. Nakamura, Takashi MizutaniAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer has been proposed to implement the normally-off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised leading to the normally- off operation. Fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally-off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm forthe device with a 1.9-μm-long gate. By etching-off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance. The transconductance was increased from 130 to 145 mS/mm by annealing the devices at 250 °C for 20 minutes in a N2 atmosphere. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
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AlGaN/GaN HEMTs With Thin InGaN Cap Layer for Normally Off Operation
IEEE Electron Device Letters, 2007Co-Authors: Takashi Mizutani, M. Ito, Shigeru Kishimoto, F. NakamuraAbstract:AlGaN/GaN HEMTs with a thin InGaN cap layer have been proposed to implement the normally off HEMTs. The key idea is to employ the polarization-induced field in the InGaN cap layer, by which the conduction band is raised, which leads to the normally off operation. The fabricated HEMT with an In0.2Ga0.8N cap layer with a thickness of 5 nm showed normally off operation with a threshold voltage of 0.4 V and a maximum transconductance of 85 mS/mm for the device with a 1.9-mum-long gate. By etching off the In0.2Ga0.8N cap layer at the access region using gate electrode as an etching mask, the maximum transconductance has increased from 85 to 130 mS/mm due to a reduction of the parasitic Source Resistance.
Daisuke Ueda - One of the best experts on this subject based on the ideXlab platform.
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Source Resistance reduction of algan gan hfets with novel superlattice cap layer
IEEE Transactions on Electron Devices, 2005Co-Authors: Tomohiro Murata, Masahiro Hikita, Yutaka Hirose, Yasuhiro Uemoto, K Inoue, Tsuyoshi Tanaka, Daisuke UedaAbstract:We have developed a novel AlGaN-GaN heterojunction field effect transistor (HFET) with an ultralow Source Resistance by employing the novel superlattice (SL) cap structure. The particular advantage of the SL cap, i.e., the existence of multiple layers of the polarization-induced two-dimensional electron gas (2DEG) with high mobility and high concentration at each AlGaN-GaN interface, is fully exploited for lowering the lateral Resistance and the potential barrier at the interface of the SL cap and the HFET barrier layer. By designing the AlGaN-GaN thickness ratio, we have established a method to obtain the optimized SL structure and have achieved an extremely low Source Resistance of 0.4 /spl Omega//spl middot/mm which is lower not only than HFETs with the conventional structure but also than those with the n-GaN cap structure. The SL cap HFET fabricated on a sapphire substrate exhibited excellent dc and RF performance, i.e., maximum transconductance of over 400 mS/mm, maximum drain current of 1.2 A/mm, a cutoff frequency of 60 GHz, a maximum frequency of oscillation of 140 GHz, and a very low noise figure minimum of 0.7 dB at 12 GHz.