MANUFACTURING METHODS FOR ACCURATELY ALIGNED AND SELF-BALANCED SUPERJUNCTION DEVICES

摘要

This invention discloses a method for manufacturing a semiconductor power device on a semiconductor substrate supporting a . drift region composed of an epitaxial layer. The method includes a first step of growing a first epitaxial layer followed by forming a first hard mask layer on top of the epitaxial layer; a second step of 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; and a third step of repeating the first step and the second step by applying the same first and second implant masks to form a plurality of epitaxial layers, each of which is implanted with the dopant regions of the alternating conductivity types. Then the manufacturing processes proceed by carrying out a device manufacturing process on a top side of the epitaxial layer on top of the dopant regions of the alternating conductivity types with a diffusion process to merge the dopant regions of the alternating conductivity types as doped columns in the epitaxial layers.

主权项

1. A method for manufacturing a semiconductor power device on a semiconductor substrate supporting a drift region composed of an epitaxial layer thereon, the method comprising:
1) growing a first epitaxial layer followed by forming a first hard mask layer on top of the epitaxial layer; 2) applying a first implant mask to open a plurality of implant windows in ire the hard mask and implanting a dopant of first conductivity type forming a plurality of space apart doped regions of the first conductivity type; 3) applying a second implant mask on top of the hard mask for blocking some of the implant windows to implant a plurality of dopant regions of second conductivity type opposite to the first conductivity type, the first conductivity type doped regions and the second conductivity type doped regions being arranged alternately to each other in the first epitaxial laver; and 4) repeating the step 1) to step 3) by applying the same first and second implant masks to form a plurality of epitaxial layers and implanting each of the epitaxial layers to form the dopant regions of the alternating conductivity types arranged alternately to each other in each of the epitaxial layers.