Performance Limits of Vertical 4H-SiC and 2H-GaN Superjunction Devices

Abstract

We have evaluated the specific on-resistance (Ron,sp) vs. BV trade-off limit of vertical superjunction (SJ) devices for 4H-SiC and 2H-GaN using a previously published analytical model. In addition, we have identified and replaced some unsuitable assumptions found in previous work. Our results show that the Ron,sp of vertical SJ devices is between one and four orders of magnitude lower than the 1D limit of 4H-SiC and 2H-GaN devices at same breakdown voltage, but significantly higher than the previous projected limit for 4H-SiC. The optimized specific on-resistance for SJ devices is lower than that for conventional devices by factors of 3X and 100X for 1kV and 10kV devices respectively. These figures are, however, 25X higher than previous projections.