The performance comparison and the temperature profile of AlGaN/GaN HEMT on different substrates are investigated. It results the maximum drain-source current (I_DS) of 1.08 A/mm, 1.04 A/mm, 0.81 A/mm and 0.669 A/mm for AlGaN/GaN HEMT on Diamond, Sapphire, Silicon Carbide and Silicon substrates respectively. In addition, it contributes the breakdown voltage of 62 V, 100.4 V, 174 V and 298 V for Sapphire, Diamond, Silicon and Silicon Carbide based HEMT respectively. It also exhibits the maximum current gain cut off frequency of 17.4 GHz, 25 GHz, 45.91 GHz and 47.07 GHz for the HEMT grown on SiC, Silicon, Sapphire and Diamond substrates respectively. The trade off between the breakdown voltage and the cut-off frequency is observed in all HEMT devices. Hence, the Johnson figure of merit (f_T × BV_GD) is calculated to inspect the choice of substrate for AlGaN/GaN HEMT device. Furthermore, the simulation result reveals very high Johnson figure of merit for the HEMT grown on Silicon Carbide substrate (5.18 × 10¹² V/s), than Sapphire (2.84 × 10¹² V/s), Silicon (4.35 × 10¹² V/s) and Diamond (4.72 × 10¹² V/s) based HEMT devices. Hence, the SiC based HEMT will be a trend for future high power and high frequency applications.

研究了不同衬底上AlGaN / GaN HEMT的性能比较和温度曲线。对于金刚石，蓝宝石，碳化硅和硅衬底上的AlGaN / GaN HEMT，其最大漏极-源极电流（I _DS）分别为1.08 A / mm，1.04 A / mm，0.81 A / mm和0.669 A / mm。此外，对于基于蓝宝石，金刚石，硅和碳化硅的HEMT，它分别贡献了62 V，100.4 V，174 V和298 V的击穿电压。对于分别在SiC，硅，蓝宝石和金刚石衬底上生长的HEMT，它还表现出最大电流增益截止频率为17.4 GHz，25 GHz，45.91 GHz和47.07 GHz。在所有HEMT器件中都观察到了击穿电压和截止频率之间的折衷。因此，约翰逊的品质因数（f _T计算 BV _GD）以检查AlGaN / GaN HEMT器件的衬底选择。此外，仿真结果显示，在碳化硅衬底上生长的HEMT（5.18×10 ¹²  V / s）的约翰逊品质因数比蓝宝石（2.84×10 ¹²  V / s），硅（4.35×10 ¹²  V / s）高。s）和基于Diamond（4.72×10 ¹²  V / s）的HEMT设备。因此，基于SiC的HEMT将成为未来高功率和高频应用的趋势。