In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improv...In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improve microwave power performance.The breakdown voltage(BV)is increased to more than 200 V for the fabricated device with gate-to-source and gate-to-drain distances of 1.08 and 2.92μm.A record continuous-wave power density of 11.2 W/mm@10 GHz is realized with a drain bias of 70 V.The maximum oscillation frequency(f_(max))and unity current gain cut-off frequency(f_(t))of the AlGaN/GaN HEMTs exceed 30 and 20 GHz,respectively.The results demonstrate the potential of AlGaN/GaN HEMTs on freestanding GaN substrates for microwave power applications.展开更多
Enhancement-mode(E-mode)GaN-on-Si radio-frequency(RF)high-electron-mobility transistors(HEMTs)were fabri-cated on an ultrathin-barrier(UTB)AlGaN(<6 nm)/GaN heterostructure featuring a naturally depleted 2-D electro...Enhancement-mode(E-mode)GaN-on-Si radio-frequency(RF)high-electron-mobility transistors(HEMTs)were fabri-cated on an ultrathin-barrier(UTB)AlGaN(<6 nm)/GaN heterostructure featuring a naturally depleted 2-D electron gas(2DEG)channel.The fabricated E-mode HEMTs exhibit a relatively high threshold voltage(VTH)of+1.1 V with good uniformity.A maxi-mum current/power gain cut-off frequency(fT/fMAX)of 31.3/99.6 GHz with a power added efficiency(PAE)of 52.47%and an out-put power density(Pout)of 1.0 W/mm at 3.5 GHz were achieved on the fabricated E-mode HEMTs with 1-μm gate and Au-free ohmic contact.展开更多
In this paper, we explore the electrical characteristics of high-electron-mobility transistors(HEMTs) using a TaN/AlGaN/GaN metal insulating semiconductor(MIS) structure. The high-resistance tantalum nitride(TaN) film...In this paper, we explore the electrical characteristics of high-electron-mobility transistors(HEMTs) using a TaN/AlGaN/GaN metal insulating semiconductor(MIS) structure. The high-resistance tantalum nitride(TaN) film prepared by magnetron sputtering as the gate dielectric layer of the device achieved an effective reduction of electronic states at the TaN/AlGaN interface, and reducing the gate leakage current of the MIS HEMT, its performance was enhanced. The HEMT exhibited a low gate leakage current of 2.15 × 10^(-7) mA/mm and a breakdown voltage of 1180 V. Furthermore, the MIS HEMT displayed exceptional operational stability during dynamic tests, with dynamic resistance remaining only 1.39 times even under 400 V stress.展开更多
In this study, the effects of 1 MeV electron radiation on the D-mode GaN-based high electron mobility transistors(HEMTs) were investigated after different radiation doses. The changes in electrical properties of the d...In this study, the effects of 1 MeV electron radiation on the D-mode GaN-based high electron mobility transistors(HEMTs) were investigated after different radiation doses. The changes in electrical properties of the device were obtained, and the related physical mechanisms were analyzed. It indicated that under the radiation dose of 5 × 10^(14) cm^(-2), the channel current cannot be completely pinched off even if the negative gate voltage was lower than the threshold voltage, and the gate leakage current increased significantly. The emission microscopy and scanning electron microscopy were used to determine the damage location. Besides, the radiation dose was adjusted ranging from 5 × 10^(12) to 1 × 10^(14) cm^(-2), and we noticed that the drain-source current increased and the threshold voltage presented slightly negative shift. By calculations, it suggested that the carrier density and electron mobility gradually increased. It provided a reference for the development of device radiation reinforcement technology.展开更多
报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al ...报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al Ga N / Ga N HEMT在 1.8GHz,Vds=30 V时输出功率为 2 8.93d Bm,输出功率密度达到 3.9W/mm ,功率增益为 15 .5 9d B,功率附加效率 (PAE)为 4 8.3% .在 6 .2 GHz,Vds=2 5 V时该器件输出功率为 2 7.0 6 d Bm ,输出功率密度为 2 .5 W/ mm ,功率增益为 10 .2 4 d B,PAE为 35 .2 % .展开更多
在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性...在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性的影响 .用准二维物理模型计算了 Al Ga N/ Ga N HEMT器件的输出特性 ,给出了相应的饱和电压和阈值电压 ,并对计算结果和 Al Ga N/ Ga N HEMT器件的结构优化进行了分析 .展开更多
文摘In this letter,high power density AlGaN/GaN high electron-mobility transistors(HEMTs)on a freestanding GaN substrate are reported.An asymmetricΓ-shaped 500-nm gate with a field plate of 650 nm is introduced to improve microwave power performance.The breakdown voltage(BV)is increased to more than 200 V for the fabricated device with gate-to-source and gate-to-drain distances of 1.08 and 2.92μm.A record continuous-wave power density of 11.2 W/mm@10 GHz is realized with a drain bias of 70 V.The maximum oscillation frequency(f_(max))and unity current gain cut-off frequency(f_(t))of the AlGaN/GaN HEMTs exceed 30 and 20 GHz,respectively.The results demonstrate the potential of AlGaN/GaN HEMTs on freestanding GaN substrates for microwave power applications.
基金supported in part by the National Key Research and Development Program of China under Grant 2022YFB3604400in part by the Youth Innovation Promotion Association of Chinese Academy Sciences(CAS)+4 种基金in part by CAS-Croucher Funding Scheme under Grant CAS22801in part by National Natural Science Foundation of China under Grant 62074161,Grant 62004213,and Grant U20A20208in part by the Beijing Municipal Science and Technology Commission project under Grant Z201100008420009 and Grant Z211100007921018in part by the University of CASin part by IMECAS-HKUST-Joint Laboratory of Microelectronics.
文摘Enhancement-mode(E-mode)GaN-on-Si radio-frequency(RF)high-electron-mobility transistors(HEMTs)were fabri-cated on an ultrathin-barrier(UTB)AlGaN(<6 nm)/GaN heterostructure featuring a naturally depleted 2-D electron gas(2DEG)channel.The fabricated E-mode HEMTs exhibit a relatively high threshold voltage(VTH)of+1.1 V with good uniformity.A maxi-mum current/power gain cut-off frequency(fT/fMAX)of 31.3/99.6 GHz with a power added efficiency(PAE)of 52.47%and an out-put power density(Pout)of 1.0 W/mm at 3.5 GHz were achieved on the fabricated E-mode HEMTs with 1-μm gate and Au-free ohmic contact.
基金supported by the National Natural Science Foundation of China(Grant No.1237310)The Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2020321)+1 种基金the National Natural Science Foundation of China(Grant No.92163204)The Key Research and Development Program of Jiangsu Province(Grant No.BE2022057-1)。
文摘In this paper, we explore the electrical characteristics of high-electron-mobility transistors(HEMTs) using a TaN/AlGaN/GaN metal insulating semiconductor(MIS) structure. The high-resistance tantalum nitride(TaN) film prepared by magnetron sputtering as the gate dielectric layer of the device achieved an effective reduction of electronic states at the TaN/AlGaN interface, and reducing the gate leakage current of the MIS HEMT, its performance was enhanced. The HEMT exhibited a low gate leakage current of 2.15 × 10^(-7) mA/mm and a breakdown voltage of 1180 V. Furthermore, the MIS HEMT displayed exceptional operational stability during dynamic tests, with dynamic resistance remaining only 1.39 times even under 400 V stress.
基金supported by the Key Program of the National Natural Science Foundation of China (Grant No. 62334002)the National Natural Science Foundation of China (Grant No. 62174008)。
文摘In this study, the effects of 1 MeV electron radiation on the D-mode GaN-based high electron mobility transistors(HEMTs) were investigated after different radiation doses. The changes in electrical properties of the device were obtained, and the related physical mechanisms were analyzed. It indicated that under the radiation dose of 5 × 10^(14) cm^(-2), the channel current cannot be completely pinched off even if the negative gate voltage was lower than the threshold voltage, and the gate leakage current increased significantly. The emission microscopy and scanning electron microscopy were used to determine the damage location. Besides, the radiation dose was adjusted ranging from 5 × 10^(12) to 1 × 10^(14) cm^(-2), and we noticed that the drain-source current increased and the threshold voltage presented slightly negative shift. By calculations, it suggested that the carrier density and electron mobility gradually increased. It provided a reference for the development of device radiation reinforcement technology.
文摘报道了研制的 Al Ga N / Ga N微波功率 HEMT,该器件采用以蓝宝石为衬底的非掺杂 Al Ga N/ Ga N异质结构 ,器件工艺采用了 Ti/ Al/ Ni/ Au欧姆接触和 Ni/ Au肖特基势垒接触以及 Si N介质进行器件的钝化 .研制的 2 0 0μm栅宽 T型布局 Al Ga N / Ga N HEMT在 1.8GHz,Vds=30 V时输出功率为 2 8.93d Bm,输出功率密度达到 3.9W/mm ,功率增益为 15 .5 9d B,功率附加效率 (PAE)为 4 8.3% .在 6 .2 GHz,Vds=2 5 V时该器件输出功率为 2 7.0 6 d Bm ,输出功率密度为 2 .5 W/ mm ,功率增益为 10 .2 4 d B,PAE为 35 .2 % .
文摘在考虑 Al Ga N / Ga N异质结中的压电极化和自发极化效应的基础上 ,自洽求解了垂直于沟道方向的薛定谔方程和泊松方程 .通过模拟计算 ,研究了 Al Ga N / Ga N HEMT器件掺杂层 Al的组分、厚度、施主掺杂浓度以及栅偏压对二维电子气特性的影响 .用准二维物理模型计算了 Al Ga N/ Ga N HEMT器件的输出特性 ,给出了相应的饱和电压和阈值电压 ,并对计算结果和 Al Ga N/ Ga N HEMT器件的结构优化进行了分析 .
