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:
Jan. 03, 2023
Filed:
Nov. 21, 2020
Yangtze Memory Technologies Co., Ltd., Wuhan, CN;
YANGTZE MEMORY TECHNOLOGIES CO., LTD., Wuhan, CN;
Abstract
Embodiments of a marking pattern in forming the staircase structure of a three-dimensional (3D) memory device are provided. In an example, a marking pattern for controlling a trimming rate of a photoresist trimming process includes a plurality of interleaved layers, the plurality of interleaved layers including at least two layers of different materials stacking along a vertical direction over a substrate. In some embodiments, the marking pattern also includes a central marking structure that divides the marking area into a first marking sub-area farther from a device area and a second marking sub-area closer to the device area, a first pattern density of the first marking sub-area being higher than or equal to a second pattern density of the second marking sub-area.