Patent ID: 8309405
Filing Date: 2012-11-13
Classification: H01L

Abstract:
1. A method of forming a nonvolatile memory device, comprising: forming an electrically insulating layer comprising a composite of a sacrificial layer having upper and lower surfaces and first and second mold layers directly on the upper and lower surfaces, respectively, on a substrate; forming an opening extending through the electrically insulating layer, said opening exposing inner sidewalls of the first and second mold layers and the sacrificial layer; lining a sidewall of the opening with an electrically insulating protective layer; forming a first semiconductor layer on an inner sidewall of the electrically insulating protective layer within the opening; selectively etching at least a portion of the sacrificial layer from between the first and second mold layers to define a recess therein that exposes an outer sidewall of the electrically insulating protective layer; selectively etching the exposed outer sidewall of the electrically insulating protective layer to expose a portion of the first semiconductor layer; forming a gate dielectric layer on the exposed portion of the first semiconductor layer in the recess; and forming a gate electrode on the gate dielectric layer.