Passivation of AlGaN/GaN HEMT by Silicon Nitride

We report here the passivation of AlGaN/GaN HEMT devices with silicon nitride films deposited by inductively coupled plasma chemical vapour deposition (ICPCVD). With low power ammonia plasma pretreatment and silicon nitride film passivation having refractive index of 2.01 and 2,000 A0 thickness, 80–95 % current recovery and minimum knee walkout have been achieved on different samples.