Patent ID: 6686252
Filing Date: 2004-02-03
Classification: H01L

Abstract:
A method of forming a semiconductor device with improved leakage control, comprising in the sequence recited:providing a semiconductor substrate having a top surface; forming a trench in said substrate, said trench having a bottom, a first sidewall and an opposite second sidewall; forming a blocking layer on said first and second sidewalls of said trench; removing said blocking layer from said second sidewall of said trench; forming a leakage stop implant in said substrate under a less than whole portion of the bottom of said trench, a first side of said leakage stop implant self-aligned to said blocking layer on said first sidewall of said trench and a second and opposite side of said leakage stop implant self-aligned to said second sidewall of said trench; filling said trench with an insulator; and forming an N-well in said substrate adjacent to and in contact with said first sidewall, said N-well extending under said trench and forming an upper portion of an isolation junction with said leakage stop implant, said upper portion of said isolation junction located entirely under said trench.