Patent ID: 6069057
Filing Date: 2000-05-30
Classification: H01L,Y10S

Abstract:
A method for fabricating a trench-isolation structure comprising the following steps of:(a) providing a silicon substrate;(b) forming a buffer layer overlying said silicon substrate;(c) forming a nitride layer overlying said buffer layer;(d) patterning said nitride layer to form an opening;(e) forming a polysilicon layer conformably overlying said nitride layer;(f) etching back said polysilicon layer to form spacers on sidewalls of said opening;(g) removing a portion of said buffer layer not covered by said spacers to expose said substrate;(h) etching said exposed substrate to form a trench, and removing said spacers;(i) forming a channel stop layer in said substrate below said trench;(j) oxidizing portions of said substrate around said trench to form an oxide layer;(k) forming an isolating layer at least filling in said trench;(l) planarizing said isolating layer to form an isolating plug remaining in said trench.