Effects of various surface treatments on gate leakage, subthreshold slope, and current collapse in AlGaN/GaN high-electron-mobility transistors

摘要

The reduction in the gate leakage current and the improvement in subthreshold characteristics and current collapse in AlGaN/GaN high-electron-mobility transistors (HEMTs) with various surface treatments were investigated. We applied wet treatment, digital etching (O_2 or N_2O), or plasma treatment (CF_4 or SF_6) before SiN_x passivation. Among these treatments, SF_6 plasma treatment suppressed gate leakage current, reduced subthreshold slope, and improved pulsed current-voltage (Ⅰ-Ⅴ) characteristics most effectively.