SiC衬底AlGaN/GaN HEMT的热分析与测试

Thermal Analysis and Measuring of AlGaN/GaN HEMT Grown on SiC Substrate

对SiC衬底AlGaN/GaN HEMT的结温进行了理论计算与实测。计算中考虑了衬底材料热导率随温度的变化以及器件源、漏电阻上的热损耗,不同耗散功率下的理论计算与红外显微镜实测结果比较表明,两者相差最大不超过10℃。由于理论计算结果是在解析解的基础上运用计算机迭代计算获得,所耗时间较短,故这一结果对于改善器件结构以提高AlGaN/GaN HEMT及其MMIC电路的性能将有较大帮助。

Thermal modeling and measurement of A1GaN/GaN HEMT grown on SiC substrate are presented. Temperature dependent thermal conductivity of substrate and the power dissipated on source and drain resistances are considered during modeling. The measured temperatures agree well with calculated ones under different power dissipated, and the maximum difference between them is less than 10℃. The theoretical calculation is based on the analytical expression of temperature profile and is finished using iteration under the aid of computer. The time consumed is less than that of using numerical simulations. The obtained result will facilitate the designer to improve the performance of AlGaN/GaN HEMT and MMIC.