The effects of nitride-based plasma pre-treatment upon AlGaN/GaN high-electron-mobility transistors on silicon substrates were investigated. Here, N2 and NH3 plasma pre-treatment methods were used to overcome the RF dispersion effect caused by nitrogen-vacancy related defect reduction. It was found that the nitride-based plasma pre-treatment was effective in overcoming the RF dispersion. The NH3 plasma pre-treatment markedly reduced the RF dispersion, from 63 to 1%. This was attributed to a reduction in the effective VN-related defect density and to the elimination of carbon/oxide residuals upon the surface. A NH3 plasma pre-treatment, prior to SiNx 100nm passivation, markedly improved the total output power.

Effects of Nitride-Based Plasma Pretreatment Prior to SiNx Passivation in AlGaN/GaN High-Electron-Mobility Transistors on Silicon Substrates. J.H.Kim, H.G.Choi, M.W.Ha, H.J.Song, C.H.Roh, J.H.Lee, J.H.Park, C.K.Hahn: Japanese Journal of Applied Physics, 2010, 49, 04DF05