深入研究了两种增强型AlGaN/GaN高电子迁移率晶体管(HEMT)高温退火前后的直流特性变化.槽栅增强型AlGaN/GaN HEMT在500℃N2中退火5min后,阈值电压由0.12V正向移动到0.57V,器件Schottky反向栅漏电流减小一个数量级.F注入增强型AlGaN/GaN HEMT在400℃N2中退火2min后,器件阈值电压由0.23V负向移动到-0.69V,栅泄漏电流明显增大.槽栅增强型器件退火过程中Schottky有效势垒提高,增强了栅对沟道载流子的耗尽能力,使器件阈值电压正方向移动,同时降低了栅反向漏电流,而且使得栅能工作在更高能的正向栅压下.F注入增强型器件在退火后由于F离子对二维电子气的耗尽作用在退火后减弱,造成阈值电压负方向移动;F注入对势垒的提高作用在退火后有所减弱,引起了Schottky泄漏电流明显增大.退火后F注入增强型器件的沟道电子迁移率得到明显恢复。 The DC characteristics of two kinds of enhanced AlGaN / GaN HEMTs before and after high temperature annealing were investigated in detail.The threshold voltage increased from 0.12V forward Moving to 0.57V, the device Schottky back-gate leakage current is reduced by one order of magnitude. After the F-injection enhancement AlGaN / GaN HEMT is annealed in N2 at 400 ℃ for 2min, the threshold voltage of the device is shifted from 0.23V to -0.69V in negative direction, The current significantly increases.The Schottky effective barrier increases during the annealing of the trench-gate enhancement device, which enhances the gate-to-channel carrier depletion capability, moves the threshold voltage of the device in the positive direction and decreases the gate reverse leakage current, But also makes the gate work under a higher energy forward gate voltage.F-injection enhancement device after annealing due to F ion depletion of two-dimensional electron gas after annealing weakened, causing the threshold voltage to move in the negative direction; F injection pair The enhancement effect of the barrier is weakened after annealing, causing the Schottky leakage current to increase significantly. The channel electron mobility of the F-implanted enhancement device after annealing is significantly recovered.