Chemical vapor deposition of silicon nitride film enhanced by surface-wave plasma for surface passivation of AlGaN/GaN device

Surface passivation of AlGaN/GaN device by silicon nitride (SiN) deposition using surface-wave plasma enhanced chemical vapor deposition (SPECVD) technique which is proposed by author's group has been studied. SiN deposition condition by SPECVD using bis(dimethylamino)dimethylsilane (BDMADMS) precursor was investigated. Effect of passivation in terms of current-voltage characteristics of gateless AlGaN/GaN device is discussed by comparing the characteristics without passivation layer and with passivation layer by SPECVD and the conventional plasma chemical vapor deposition (PCVD). Increase of the current and decrease of the current hysteresis in AlGaN/GaN device were observed in SiN passivated samples by SPECVD technique. These results revealed that passivation by SPECVD technique is promising for AlGaN/GaN-based high output current transistors and their stable operation.