Counter-Doped JTE, an Edge Termination for HV SiC Devices With Increased Tolerance to the Surface Charge

In this paper, a comparison of different techniques for SiC high-voltage devices is performed using numerical simulations. In particular, the method of counter doping (CD) introduced in the junction termination extension (JTE) region to create a multizone termination effect is investigated. Simulation shows that compared with the other edge termination techniques, CD-JTE greatly reduces the sensitivity of breakdown voltage (BV) to JTE doses and surface charges. The multizone CD-JTE with outer rings shows that for a 30-μm thick epi-layer, 90% of the theoretical BV is achievable with a wide tolerance of 11 × 10¹²/cm² to the JTE dose and 85% of the theoretical BV with an increased tolerance of 6.19 × 10¹²/cm² to the positive surface charges, both superior to other JTE structures investigated in this paper.