Patent ID: 11943928
Assignee: YANGTZE MEMORY TECHNOLOGIES CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 11:
12. A method for forming a channel hole plug structure in a three-dimensional (3D) memory device, comprising:
forming an alternating dielectric stack disposed on a substrate;
forming an insulating layer and a hard mask layer on the alternating dielectric stack;
forming a channel structure penetrating the insulating layer, the hard mask layer, and the alternating dielectric stack;
forming a photoresist patterning on the hard mask layer;
using the photoresist patterning as a mask to remove a top portion of the channel structure to form a recess, wherein:
a size of a bottom aperture of the recess is greater than a size of a top surface of the channel structure; and
a size of a top aperture of the recess is greater than a size of the bottom aperture of the recess; and

forming a channel hole plug in the recess, wherein a projection of the channel hole plug in a lateral plane covers a projection of the channel structure in the lateral plane.