High Temperature Performance of AlGaN/GaN HEMTs with a Partial GaN Cap Layer

In this paper, the AlGaN/GaN HEMTs with a partial GaN cap layer was successfully fabricated. The ohmic contact, and on-state output high temperature performance of AlGaN/GaN HEMTs with a partial GaN cap layer was tested at different temperatures. The measurement results have shown that the output saturation current gradually decreases with the increasing temperature. In the mean time, the degradation of the output saturation current of AlGaN/GaN HEMTs with a partial GaN cap layer is alleviated to some extent, compared with the conventional AlGaN/GaN HEMTs. This is due to the optimization of the electric field distribution and the corresponding optimization of the thermal field distribution through ISE TCAD simulation results.