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. 27, 2022
Filed:
Jun. 23, 2020
Yangtze Memory Technologies Co., Ltd., Hubei, CN;
Yangtze Memory Technologies Co., Ltd., Hubei, CN;
Abstract
A method for forming a three-dimensional (3D) memory device is disclosed. In some embodiments, the method includes forming an alternating dielectric stack on a substrate, and forming a plurality of channel holes penetrating the alternating dielectric stack vertically to expose at least a portion of the substrate. A first mask can be formed to cover the channel holes in a first area and expose the channel holes in a second area. The method also includes forming a recess in the alternating dielectric stack in the second area, followed by forming a second mask in the recess. The second mask covers the channel holes in the second area and exposes the channel holes in the first area. The memory film at bottom of each channel hole in the first area can therefore be removed, while the memory film in the second area can be protected by the second mask.