Patent ID: 8076198

Claim:
A method of fabricating a nonvolatile memory device, the method comprising: alternately stacking first and second material layers in two or more layers on a semiconductor substrate; forming trenches on the semiconductor substrate, penetrating the stacked first and second material layers and exposing sidewalls of the first and second material layers by performing a first etching process; after performing the first etching process, removing the second material layers exposed in the trenches by performing a second etching process; wherein the first and second material layers are formed of materials that have the same main component and have different impurity contents, respectively; wherein the forming of the trenches includes forming first trenches and forming a second trench after forming the first trenches; wherein the method further includes forming a semiconductor pattern at an inner wall of the first trenches after forming the first trenches; wherein the removing of the second material layers includes removing the second material layers exposed by the second trench and exposing portions of sidewalls of the semiconductor pattern; and wherein the method further includes forming a charge storage layer and a conductive pattern on the exposed semiconductor pattern.