Patent ID: 7081382
Filing Date: 2006-07-25
Classification: H01L

Abstract:
1. A method of fabricating a trench device structure with a single-side buried strap, comprising the steps of: providing a semiconductor substrate having a deep trench therein; forming a buried trench capacitor in a lower portion of the deep trench; forming a collar insulating layer lining an upper portion of the deep trench; forming a first conductive layer overlying the buried trench capacitor in the trench and surrounded by and lower than the collar insulating layer by a predetermined height; removing a first portion of the collar insulating layer from the deep trench to expose a first portion of the semiconductor substrate while a second portion of the collar insulating layer remains to isolate a second portion of the semiconductor substrate; forming a second conductive layer overlying the first conductive layer in the deep trench, wherein the second conductive layer is lower than the surface of the semiconductor substrate and a portion of the second conductive layer is isolated from the semiconductor substrate by the second portion of the collar insulating layer; and forming the single-side buried strap region in the semiconductor substrate directly contacting the second conductive layer without isolation by the collar insulating layer.