Reliability improvement achieved by N2O radical treatment for AlGaN/GaN heterojunction field-effect transistors

摘要

Recently, O2 or N2O plasma treatment has been extensively investigated about the passivation effect of AlGaN/GaN HFETs [1–3]. However, the effect was not consistent. Due to ion bombardment on the sample surface, the devices might be significantly degraded [2,3], suggesting that it might be difficult to suppress the plasma damage. On the other hand, Tapajna et al. [4] have reported the reliability issue of such oxidation process. In this work, a method called N2O radical treatment will be introduced. With this method, we suppressed the current collapse of AlGaN/GaN HFETs by ∼40%. And the reliability was also improved by ∼60%.