Patent ID: 7592229
Filing Date: 2009-09-22
Classification: H01L

Abstract:
1. A method of fabricating a recess-gate transistor device, comprising: providing a semiconductor substrate having thereon a gate trench etched into said semiconductor substrate, and said gate trench comprising a trench bottom and a trench sidewall; forming, on the trench sidewall, a spacer comprising a polysilicon layer; forming a trench bottom oxide layer at said trench bottom; removing said spacer to expose said trench sidewall; forming a source/drain diffusion region on said trench sidewall; forming an insulating mask layer on said trench sidewall after forming the source/drain diffusion region; removing said trench bottom oxide layer to form an arc-shaped trench bottom after forming the insulating mask layer; forming a gate dielectric layer on said arc-shaped trench bottom; and filling said gate trench with conductive gate material after forming the gate dielectric layer.