Channel modulated AlGaN/GaN HEMTs employing fluoride plasma treatment

We proposed channel modulated AlGaN/GaN high electron mobility transistors (HEMTs) employing fluoride plasma treatment and carried out the detailed numerical simulation of device operation using ISE-TCAD. The reduction of peak electric field is required to achieve the high breakdown voltage of AlGaN/GaN HEMTs. Proposed channel modulated AlGaN/GaN HEMTs created the fluoride plasma treated region between the gate and the drain. The fluoride plasma treated region modulated the two-dimensional electron gas (2-DEG) channel concentration, and effectively reduced the peak electric field without any field plates. The reduction of peak electric field in the gate-to-drain region made the breakdown voltage increased by 206 %. DC characteristics of channel modulated AlGaN/GaN HEMTs remained practically the same as those of the conventional AlGaN/GaN HEMTs. The breakdown voltage could be increased without a significant degradation of DC characteristics due to the SiO₂ passivation layer. The deposition of SiO₂ passivation layer combining with fluoride plasma treatment is a powerful process for channel modulated AlGaN/GaN HEMTs.