Trench sidewall doping for lateral power devices

Sidewall doping of trenches with a high aspect ratio and a high grade of anisotropy (90° +- 0.5°) by ion implantation has been investigated. Two-dimensional (2D) process simulation and delineation experiments have shown a good agreement between simulation and experimental results. The doping of the trenches has been evaluated in order to manufacture functional wells for lateral power devices. 2D device simulation has been performed to compare optimized sidewall profiles of lateral power devices with the profiles reached by ion implantation. From these data, the process parameters for the ion implantation process referring to optimal device performance have been determined.