Title:
METHOD FOR FORMING STAIRCASE STRUCTURE OF THREE-DIMENSIONAL MEMORY DEVICE
Document Type and Number:
WIPO Patent Application WO/2019/200565
Kind Code:
A1
Abstract:
Embodiments of a method for forming a staircase structure of 3D memory devices are disclosed. The method comprises (i) forming an alternating layer stack including multiple layers disposed on a substrate in a vertical direction; (ii) removing a portion of the alternating layer stack to form multiple step-platforms in a staircase region of the alternating layer stack; (iii) forming a hard mask layer to cover top surfaces of the step-platforms; (iv) forming multiple openings in the hard mask layer to expose a portion of each of the step-platforms; (v) forming a photoresist layer to cover the top surfaces of the step-platforms and the hard mask layer; (vi) using a same set of trim-etch processes to pattern the photoresist layer to form a set of staircases on each of the step-platforms; (vii) removing the photoresist layer and the hard mask layer; and repeating (iii), (iv), (v), (vi) and (vii) sequentially.
Inventors:
ZHOU YUTING (CN)
XIAO LIHONG (CN)
XU JIAN (CN)
LI SIZHE (CN)
TANG ZHAOHUI (CN)
LI ZHAOSONG (CN)
XIAO LIHONG (CN)
XU JIAN (CN)
LI SIZHE (CN)
TANG ZHAOHUI (CN)
LI ZHAOSONG (CN)
Application Number:
PCT/CN2018/083562
Publication Date:
October 24, 2019
Filing Date:
April 18, 2018
Export Citation:
Assignee:
YANGTZE MEMORY TECH CO LTD (CN)
International Classes:
H01L27/11578
Foreign References:
| US20180082940A1 | 2018-03-22 | |||
| KR20110001691A | 2011-01-06 | |||
| US20140363980A1 | 2014-12-11 | |||
| CN105514018A | 2016-04-20 |
Attorney, Agent or Firm:
NTD UNIVATION INTELLECTUAL PROPERTY AGENCY LTD. (CN)
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