Three-dimensional memory device and manufacturing method thereof

Abstract

A method for manufacturing three-dimensional memory, comprising the steps of: forming a stack structure composed of a plurality of first material layers and a plurality of second material layers on a substrate; etching the stack structure to expose the substrate, forming a plurality of first vertical openings; forming a filling layer in each of the first openings; etching the stack structure around each of the first openings to expose the substrate, forming a plurality of second vertical openings; forming a vertical channel layer and a drain in each of the second openings; removing the filling layer by selective etching, re-exposing the first openings; partially or completely removing the second material layers by lateral etching, leaving a plurality of recesses; forming a plurality of gate stack structure in the recesses; forming a plurality of common sources on and/or in the substrate at the bottom of each of the first openings. In accordance with the three-dimensional memory manufacturing method of the present invention, the deep trenches of word-line in the TCAT three-dimensional device are replaced with deep-hole etching to realize the same function, thereby improving the integration density, simplifying the etching process of stacked structure, and maintaining the control performance of the metal gate.

Dependencies are inferred from the claim text.