[MoC4] GaN HEMTs for Power (I)

5:30 PM - 5:45 PM JST(8:30 AM - 8:45 AM UTC)

[MoC4-05] Electro-Thermal Characterization of AlGaN/GaN HEMTs Uder Different Pulsing Modes by Thermoreflectance Thermal Imaging

〇Minji Kim¹, Jiun Oh¹, Joon Seop Kwak¹ (1. Korea Inst. of Energy Tech. (Korea))

This study explores how different pulsing conditions—specifically between gate pulse and drain pulse—trigger fundamentally different self-heating effects in depletion-mode AlGaN/GaN HEMTs, even under identical power dissipation. Since localized temperature increases near the gate edge and drain area significantly affect the device's reliability, high-resolution thermoreflectance microscopy was utilized for temperature mapping with sub-micron resolution. The technique discussed converts reflectance changes into absolute temperature measurements using calibrated thermoreflectance coefficients, C_TR. Thermal image indicates that both gate pulse and drain pulse create distinct thermal hotspots between gate and drain region. These observations offer critical insights for improving heat dissipation and understanding failure mechanisms related to hotspot formation in pulsing scenarios.