SUPER JUNCTION FOR SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING THE SAME

摘要

A super junction for semiconductor device includes a silicon substrate with a first conductive type epitaxial layer, a plurality of highly-doped second conductive type columns formed in the first conductive type epitaxial layer, and a plurality of lightly-doped (first conductive type or second conductive type) side walls formed on outer surfaces of the highly-doped second conductive type. The semiconductor device is super-junction MOSFET, super junction MOSFET, super junction Schottky rectifier, super junction IGBT, thyristor or super junction diode.

主权项

1. A method for manufacturing super junction for semiconductor device, comprising steps in the sequence of:
(a) providing a silicone substrate and forming a first conductive type epitaxial layer thereon; (b) forming two patterned mask layers on the first conductive type epitaxial layer, the patterned a mask layers comprising a top mask layer and a bottom mask layer under the top mask layer; (c) ion-implanting a high-concentration second conductive type ion on a portion of the first conductive type epitaxial layer, the portion is not covered by the two patterned mask layers; (d) undercutting the bottom mask layer and removing the top mask layer; (e) ion-implanting a low-concentration second conductive type ion or a low-concentration first conductive type on a portion of the first conductive type epitaxial layer, the portion is not covered by the undercut bottom mask layer; (f) removing the undercut bottom mask layer and forming a first conductive type epitaxial covering layer on resulting structure; (g) repeating above step (b) to step (f) to form a plurality of high-concentration second conductive type dopant layers and a plurality of low-concentration dopant layers; (h) forming a field oxide layer on resulting structure and performing thermal driving-in to connect the plurality of high-concentration second conductive type dopant-layers and to connect the plurality of low-concentration dopant-layers such that a heavily-doped second conductive type column and a lightly-doped sidewall are formed in the first conductive type epitaxial layer.