RTN Analysis of Schottky p-GaN gate HEMTs Under Forward Gate Stress: Impact of Temperature

Abstract

This study presents a comprehensive analysis of random telegraph noise (RTN) to evaluate the impact of forward gate bias (VGS) and temperature (T) on defects creation and activation in the gate epi-stack of GaN-based Schottky p-GaN gate HEMTs. Results reveal three RTN components in the fresh device currents at elevated temperatures (90 °C to 150 °C), attributed to pre-existing defects within the AlGaN barrier, influencing both the gate leakage and the drain current. Temperature-dependent RTN analysis is used to extract the activation energies of these traps. Conversely, no RTN components are observed in fresh device currents at lower temperatures (≤70 °C), highlighting the role of thermal excitation in defects activation. Under forward gate stress, four additional RTN components emerge, suggesting new traps formation. Findings highlight the combined roles of temperature and VGS in activating pre-existing defects and inducing new ones within the gate epi-stack of Schottky p-GaN gate HEMTs.