Comparison of SiO2-based double passivation scheme by e-beam evaporation and PECVD for surface passivation and gate oxide in AlGaN/GaN HEMTs

- Double-insulator scheme by different deposition methods are first studied.
- E-beam-based SiO2 shows the best result due to the reduction of gate leakage current.
- E-beam-based SiO2 and double scheme form a competitive insulator for HEMT.
- Authors plan to try other tool, such as LPCVD, TCVD and ADM to obtain optimal result.