Enhancement mode AIGaN/GaN HEMTs by fluorine ion thermal diffusion with high Vth stability

摘要

A method of fluorine ion thermal diffusion has been proposed to realize enhancement-mode AIGaN/GaN HEMTs. By AIF(3) solid diffusion source, fluorine ion has successfully diffused in the gate region of AIGaN layer at 800 degrees C 2 h with a diffusion depth about 20 nm demonstrated by secondary ion mass spectrometry. The fabricated device exhibits a positive threshold voltage of 1.8 V, a drain current density of 95 mA mm(-1) at V-g = 4 V, a peak transconductance of 50 mS mm(-1), a breakdown voltage of 700 V. Besides, the device is also demonstrated with good V-th stability under different stress conditions. (C) 2019 The Japan Society of Applied Physics