Methods for forming n-type buried layer in a substrate by performing non-doping implant through oxide layer formed over the substrate

Abstract

Disclosed herein are approaches for reducing buried channel recess depth using a non-doping ion implant prior to formation of the buried channel. In one approach, a method may include providing an oxide layer over a substrate, performing a non-doping implantation process through the oxide layer to form an amorphous region in the substrate, and forming a photoresist over the oxide layer. The method may further include forming a buried layer in the substrate by implanting the substrate through an opening in the photoresist, and performing an oxidation and dopant drive-in process to the amorphous region and to the buried layer to form a second oxide layer.