The introduction of AlGaN back-barrier increases the confinement of the two-dimensional electrons and further improves the high-frequency performance of AlGaN/AlN/GaN HEMTs. We investigate the effect of AlGaN back-barrier on irradiation tolerance of GaN-based HEMTs in terms of 2DEG density and electron scattering. The Schroödinger-Poisson equations are solved using a self-consistency method to calculate the conduction energy band and 2DEG density, which takes into account the Ga vacancies caused by proton irradiation. The electron scattering depending on phonons, ionized impurities, dislocations, and the interface AlN/GaN interface roughness is also studied, and 2DEG mobility is calculated for GaN-based HEMTs with and without back-barrier. The calculation results show that, after the same proton irradiation, the 2DEG density and mobility in GaN-based HEMT with back-barrier decrease more dramatically than that without back-barrier. The results may give some suggestions to those designing the radiation-resistant GaN-based HEMTs.

AlGaN背势垒的引入增加了二维电子的约束，进一步提高了AlGaN/AlN/GaN HEMT的高频性能。我们在 2DEG 密度和电子散射方面研究了 AlGaN 背势垒对基于 GaN 的 HEMT 的辐照耐受性的影响。薛定谔-泊松方程使用自洽方法求解，以计算导能带和 2DEG 密度，其中考虑了质子辐射引起的 Ga 空位。还研究了取决于声子、电离杂质、位错和界面 AlN/GaN 界面粗糙度的电子散射，并计算了具有和不具有背势垒的 GaN 基 HEMT 的 2DEG 迁移率。计算结果表明，相同质子辐照后，有背势垒的 GaN 基 HEMT 的 2DEG 密度和迁移率比没有背势垒的 HEMT 下降得更显着。研究结果可为设计抗辐射 GaN 基 HEMT 的人员提供一些建议。