부산대학교 도서관

The modified thermal device model was adapted to determine the channel temperature of the AlGaN/GaN HEMT operating under pulsed and quasi-static conditions. The differential analysis of the isothermal and thermal part of the resulting current, as well as ambient temperature variation, is utilized to determine the average channel temperature. Ambient temperature increases in the device operating range is required under low-power operation only, while under high-power operation the thermal stress of the device is significantly reduced due to small ambient temperature variation. In addition, trapping phenomena incorporation is demonstrated to obtain more accurate results utilizing the HEMT threshold voltage shift and transconductance. For experimental verification of the thermal model, Al0.25Ga0.75N/GaN HEMT electrical properties are investigated. Experimentally verified results are in a good agreement with numerical simulations.