变温C-V和传输线模型测量研究AlGaN/GaN HEMT温度特性

Temperature Characteristics of AlGaN/GaN HEMTs Using C-V and TLM for Evaluating Temperatures

通过对异质结材料上制作的肖特基结构变温C-V测量和传输线模型变温测量，研究了蓝宝石衬底AIGaN／GaN异质结高电子迁移率晶体管的直流特性在25-200℃之间的变化，分析了载流子浓度分布、沟道方块电阻、欧姆比接触电阻和缓冲层泄漏电流随温度的变化规律，得出了器件饱和电流随温度升高而下降主要由输运特性退化造成，沟道泄漏电流随温度的变化主要由栅泄漏电流引起的结论，同时，证明了GaN缓冲层漏电不是导致器件退化的主要原因。

The DC characteristics of AIGaN/GaN HEMTs are measured in a temperature range from 25 to 200℃. On the same wafer, Schottky C-V and transmission line model measurements are carried out at different temperatures. The temperature dependence of the distribution of the two-dimensional electron gas, the sheet resistance, the ohmic specific contact resistance, and the buffer leakage current are analyzed. We conclude that the reduced saturation current is mainly due to the degradation of the electron transport property. The channel leakage current arises from the gate leakage current, and the leakage of the GaN buffer layer plays a secondary role.