Design of Ion-Implanted Junction Termination Extension for Vertical GaN Pin Rectifiers

Abstract

In recent years, GaN bipolar switches have attracted much research interests for the implementation of high-power and high-voltage applications that laterally-scaled GaN-based power field-effect transistors were not optimally implemented. In the context of vertical power device design, a proper electric field engineering would be of crucial importance to exploit the device performance that could potentially reach the theoretical power switching limit for a given material system. In this report, we studied the effectiveness of the floating guard ring design of a vertical GaN p-i-n (PIN) rectifiers for kV-range applications using a planar device fabrication that involves the use of ion-implantation as a mean of device isolation and the formation of floating guard rings. We found the gap between floating guard ring has major impact on the electric field distribution in vertical PIN rectifiers. As a result, 1 kV of blocking voltage was achieved by 6 floating guard ring design using nitrogen-ion implanted isolation.