Determining Drain Current Characteristics and Channel Temperature Rise in GaN HEMTs

We experimentally investigated how self-heating affected the transient response of drain current in AlGaN/GaN high-electron-mobility transistors. Since drain current depends on temperature, we measured the drain current to assess the transient temperature rise of the active area. Based on the transient temperature rise, we used the structure function method to analyze the resistance to temperature rise. This can be used to extract the chip temperature rise even for a packaged device. We verified the proposed electrical method by comparing its results to those measured by the forward-Schottky-junction-characteristic method, revealing good agreement.