Normally-off AlGaN channel heterostructure field effect transistors (HFETs) have been proposed and investigated numerically by taking advantage of the polarization engineering perspective in III-nitrides. The utilization of polarization-matched InAlN/AlGaN heterostructures shifted the threshold voltage to approximately 1.1 V for an Al0.3Ga0.7N channel HFET. Compared to the AlGaN/GaN HFEF with a low breakdown voltage, the normally-off InAlN/AlGaN HFETs show substantially enhanced breakdown characteristics. Besides, the two-dimensional electron gas (2DEG) mobility in the InAlN/AlGaN HFETs exhibits much less reduction with the increasing temperature than that in the AlGaN/GaN HFET, according to the calculation of electron mobility dominated by alloy disorder scattering and polar optical phonon scattering. As a result, the temperature dependences of the power figures of merit based on the conduction loss consideration in terms of 2DEG mobility variation and Johnson figure of merit show superior potential for polarization-matched InAlN/AlGaN HFETs in high-power and high-frequency electronics applications particularly operating at elevated temperatures. This work provides a useful way for demonstration of normally-off AlGaN channel HFETs and is also helpful for design of future devices, which can be beneficially exploited from polarized III-nitride heterostructures.

中文翻译：

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通过 InAlN/AlGaN 异质结构的极化工程，用于演示常关型 AlGaN 沟道场效应晶体管

通过利用 III 族氮化物的极化工程视角，已经提出并数值研究了常关型 AlGaN 沟道异质结构场效应晶体管 (HFET)。对于 Al0.3Ga0.7N 沟道 HFET，极化匹配 InAlN/AlGaN 异质结构的使用将阈值电压移动到大约 1.1 V。与具有低击穿电压的 AlGaN/GaN HFEF 相比，常关型 InAlN/AlGaN HFET 显示出显着增强的击穿特性。此外，根据由合金无序散射和极性光学主导的电子迁移率计算，InAlN/AlGaN HFET 中的二维电子气（2DEG）迁移率随温度升高的降低幅度远小于 AlGaN/GaN HFET。声子散射。因此，基于 2DEG 迁移率变化和约翰逊品质因数方面的传导损耗考虑的功率品质因数的温度依赖性显示了极化匹配 InAlN/AlGaN HFET 在高功率和高频电子应用中的优越潜力，特别是在升高的温度。这项工作为演示常关型 AlGaN 沟道 HFET 提供了一种有用的方法，也有助于未来器件的设计，这可以从极化的 III 族氮化物异质结构中得到有益的利用。