Patent ID: 6100159
Filing Date: 2000-08-08
Classification: H01L

Abstract:
A method for fabricating a silicon substrate for use in fabricating a quasi-soi semiconductor device, said method comprising the steps of:(a) providing a silicon substrate member;(b) fabricating at least one passivation layer consisting of silicon nitride over said silicon substrate member and protecting an underlying substrate surface region for facilitating subsequent fabrication of at least one pair of isolation trenchs;(c) fabricating at least one pair of isolation trench regions by etching portions of said at least one passivation layer and portions of said substrate surface region and forming said at least one pair of isolation trenches, said formed at least one pair of isolation trenches defining an epitaxial silicon growing region;(d) fabricating an epitaxial silicon layer over said epitaxial silicon growing region;(e) fabricating an MOS gate structure region for said quasi-soi semiconductor device, said MOS gate structure region comprising a silicon dioxide layer grown over said epitaxial silicon layer and a polysilicon layer deposited over said silicon dioxide layer;(f) fabricating a spacer region around said MOS gate structure region, said spacer region being formed by a low-pressure CAD (LPCVD) process depositing a silicon dioxide layer and performing an anisotropic plasma etching step;(g) fabricating a channel region beneath said silicon dioxide layer recited in step (e) and said spacer region, said channel region being formed by an angled implant process for implanting a dopant material;(h) fabricating a salicidated source region for said quasi-soi semiconductor device adjacent said channel region; and(i) fabricating a salicidated drain region for said quasi-soi semiconductor device on said epitaxial layer at an opposing end of said source region, said source and drain regions comprising implant dopant material extending from said channel region to form an electrical path to a respective one of said isolation trench regions.