The potential of AlGaN-based ultrawide-bandgap high-electron-mobility transistors (HEMTs) with high (> 60%) Al composition for use in high-power switching applications is studied. The devices are simulated with a gate length of 2 µm, and their figures of merit are evaluated as functions of the gate-to-drain distance, operating temperature, and different substrates. At room temperature (RT), the maximum drain current, I_D (at a gate voltage of V_GS = 2 V), I_ON/I_OFF ratio, threshold voltage, and subthreshold swing are found to be 219 mA/mm, ~ 10⁹, −11.4 V, and 85 mV/decade, respectively, at a drain bias of V_DS of 15 V for the device with L_GD = 3.5 µm. The breakdown voltages are calculated as 396–830 V for the devices with gate-to-drain spacing L_GD varying from 3.5 to 9.5 µm, respectively. The lowest OFF-state power dissipation of 0.73 nW/mm is found for the device with L_GD = 3.5 µm at RT. The device also shows excellent behavior at high temperatures. The high-Al-content AlGaN-based HEMT with an AlN/sapphire substrate shows outstanding thermal stability and exhibits little thermal droop at high voltages. These results indicate that the structure proposed herein is an excellent choice for high-power switching devices.

中文翻译：

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用于高功率开关的超宽带AlGaN基HEMT

研究了具有高（> 60％）Al组成的基于AlGaN的超宽带隙高电子迁移率晶体管（HEMT）在高功率开关应用中的潜力。器件以2 µm的栅极长度进行仿真，其品质因数根据栅极到漏极的距离，工作温度和不同的基板进行评估。在室温（RT）下，发现最大漏极电流I _D（在V _GS  = 2 V的栅极电压下），I _ON / I _OFF比，阈值电压和亚阈值摆幅约为219 mA / mm，〜在V _DS的漏极偏置下分别为10 ⁹，-11.4 V和85 mV /十倍对于L _GD  = 3.5 µm的器件，最大为15V 。对于栅漏间距L _GD分别为3.5至9.5 µm的器件，击穿电压计算为396–830V 。对于 在RT时L _GD = 3.5 µm的器件，其关断状态功耗最低，为0.73 nW / mm 。该器件在高温下也表现出出色的性能。具有AlN /蓝宝石衬底的高Al含量基于AlGaN的HEMT具有出色的热稳定性，并且在高电压下几乎没有热下垂。这些结果表明，本文提出的结构是高功率开关器件的绝佳选择。