质子辐照对AlGaN/GaN HEMT亚阈值摆幅特性的影响

Influence of Proton Irradiation on Subthreshold Swing Characteristics of AlGaN/GaN HEMTs

研究了具有不同栅漏间距的AlGaN/GaN高电子迁移率晶体管(HEMT)的亚阈值摆幅特性在0.4 MeV质子辐照(质子总注量为2.16×10^(12)cm^(-2))后的变化规律。质子辐照前,各器件的亚阈值摆幅基本一致;质子辐照后,器件的亚阈值摆幅随着栅漏间距的减小而逐渐降低。基于辐照前后器件的电容-电压曲线和输出特性得到低场载流子输运特性,并据此分析了亚阈值摆幅的变化原因。发现与器件尺寸相关的极化散射效应是不同尺寸器件在辐照后亚阈值摆幅发生不同变化的主要原因。为AlGaN/GaN HEMT的性能优化提供了全新的视角与维度。

The change rule of subthreshold swing characteristics for AlGaN/GaN high electron mobility transistors(HEMTs) with different gate-drain distances after 0.4 MeV proton irradiation(proton total fluence is 2.16 × 10^(12)cm^(-2)) was studied.Before proton irradiation, the subthreshold swing of each device was basically the same.After proton irradiation, the subthreshold swing of the device gradually decreased with the decrease of gate-drain distance.The low-field carrier transport characteristic was obtained based on the capacitance-voltage curves and output characteristic of the device before and after irradiation, and the reasons for the change of subthreshold swing were analyzed accordingly.It is found that the polarization scattering effect related to the size of the device is the main reason for the different changes of the subthreshold swing of devices with different sizes after irradiation.It provides a new perspective and dimension for optimizing the performances of AlGaN/GaN HEMTs.