High-Performance LPCVD-SiNx/InAlGaN/GaN MIS-HEMTs With 850-V 0.98-m Omega.cm(2) for Power Device Applications

Abstract

We demonstrate the electrical performances of the quaternary InAlGaN/GaN MIS-HEMTs with high quality SiNx gate dielectric and surface passivation layer deposited by low pressure chemical vapor deposition (LPCVD) at 780 degrees C. Excellent LPCVD-SiNx/InAlGaN interface and SiNx film quality were obtained, resulting in very high output current density, a very small threshold voltage hysteresis and steep subthreshold slope. The LPCVD-SiNx/InAlGaN/GaN MIS-HEMT device exhibited high on/off current ratio, large gate voltage swing, high breakdown voltage, and very low dynamic on-resistance (R-ON) degradation, meaning effective current collapse suppression compared to the plasma enhanced chemical vapor deposition -SiN x /InAlGaN/GaN MIS-HEMTs. The corresponding specific on-resistance (RoN, sp ) for LPCVD-SiN x device was as low as 0.98 m Omega.cm(2), yielding a high figure of merit of 737 MW/cm(2) . These results demonstrate a great potential of the LPCVD-SiNx /InAlGaN/GaN MIS-HEMTs for high-power switching applications.