Effect of Silicon Nitride PECVD Growth on AlGaN/GaN HEMT Dispersion and Breakdown Characteristics

摘要

In this work, we have fabricated AlGaN/GaN HEMTs and examined the effect of modifications to the Si_3N_4 deposition process on device RF dispersion and breakdown. Higher RF power can be attained with a device having low dispersion and high breakdown. Some researchers have utilized silicon dioxide as a passivation layer to increase the device breakdown but these devices still suffered from dispersion. Others have used silicon nitride which successfully reduces dispersion, but these devices have lower breakdown as a result of the nitride. By modifying the deposition parameters of the PECVD silicon nitride process, we have successfully achieved lower dispersion and enhanced breakdown.