Manufacturing methods for accurately aligned and self-balanced superjunction devices

摘要

A method for manufacturing a semiconductor power device on a semiconductor substrate supporting a drift region composed of an epitaxial layer by growing a first epitaxial layer followed by forming a first hard mask layer on top of the epitaxial layer; applying a first implant mask to open a plurality of implant windows and applying a second implant mask for blocking some of the implant windows to implant a plurality of dopant regions of alternating conductivity types adjacent to each other in the first epitaxial layer; repeating the first step and the second step by applying the same first and second implant masks to form a plurality of epitaxial layers then carrying out a device manufacturing process on a top side of the epitaxial layer with a diffusion process to merge the dopant regions of the alternating conductivity types as doped columns in the epitaxial layers.