The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 29, 2020
Filed:
Nov. 20, 2018
Yangtze Memory Technologies Co., Ltd., Wuhan, CN;
Baoyou Chen, Wuhan, CN;
Weihua Cheng, Wuhan, CN;
Hai Hui Huang, Wuhan, CN;
Zhuqing Huang, Wuhan, CN;
Guanping Wu, Wuhan, CN;
Hongbin Zhu, Wuhan, CN;
Yu Qi Wang, Wuhan, CN;
YANGTZE MEMORY TECHNOLOGIES CO., LTD., Wuhan, CN;
Abstract
Embodiments of methods for forming channel holes in 3D memory devices using a nonconformal sacrificial layer are disclosed. In an example, a dielectric stack including interleaved first dielectric layers and second dielectric layers is formed on a substrate. An opening extending vertically through the dielectric stack is formed. A nonconformal sacrificial layer is formed along a sidewall of the opening, such that a variation of a diameter of the opening decreases. The nonconformal sacrificial layer and part of the dielectric stack abutting the nonconformal sacrificial layer are removed. A channel structure is formed in the opening after removing the nonconformal sacrificial layer and part of the dielectric stack.