Silicon nitride passivation with ammonia plasma pretreatment for improving reliability of AlGaN/GaN HEMTs

摘要

This invention pertains to an electronic device and to a method for making it. The device is a heterojunction transistor, particularly a high electron mobility transistor, characterized by presence of a 2 DEG channel. Transistors of this invention contain an AlGaN barrier and a GaN buffer, with the channel disposed, when present, at the interface of the barrier and the buffer. Surface treated with ammonia plasma resembles untreated surface. The method pertains to treatment of the device with ammonia plasma prior to passivation to extend reliability of the device beyond a period of time on the order of 300 hours of operation, the device typically being a 2 DEG AlGaN/GaN high electron mobility transistor with essentially no gate lag and with essentially no rf power output degradation.