US 12,148,618 B2
Mask structure, semiconductor structure and methods for manufacturing same
Penghui Xu, Hefei (CN); Qiang Wan, Hefei (CN); Tao Liu, Hefei (CN); Sen Li, Hefei (CN); Jun Xia, Hefei (CN); Kangshu Zhan, Hefei (CN); and Jinghao Wang, Hefei (CN)
Assigned to CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed by CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed on Jan. 14, 2022, as Appl. No. 17/647,993.
Application 17/647,993 is a continuation of application No. PCT/CN2021/105740, filed on Jul. 12, 2021.
Claims priority of application No. 202110333446.6 (CN), filed on Mar. 29, 2021.
Prior Publication US 2022/0310393 A1, Sep. 29, 2022
Int. Cl. H01L 21/033 (2006.01); H10B 12/00 (2023.01)
CPC H01L 21/0338 (2013.01) [H01L 21/0335 (2013.01); H01L 21/0337 (2013.01); H10B 12/00 (2023.02)] 17 Claims
OG exemplary drawing
 
1. A method for manufacturing a mask structure, comprising:
forming a pattern transfer layer, a first etching stop layer, a first sacrificial layer and a first hard mask layer sequentially stacked from bottom to top;
patterning the first sacrificial layer and the first hard mask layer, to obtain a first sacrificial pattern, the first sacrificial pattern exposing the first etching stop layer;
forming a first initial mask pattern on side walls of the first sacrificial pattern;
removing the first sacrificial pattern;
removing, based on the first initial mask pattern, a part of the first etching stop layer of which a top surface being exposed;
removing the first initial mask pattern, and using a remaining part of the first etching stop layer on an upper surface of the pattern transfer layer as a first mask pattern, the first mask pattern extending in a first direction;
forming a first filling layer, the first filling layer covering an upper surface of an exposed part of the pattern transfer layer and the first mask pattern, wherein an upper surface of the first filling layer is higher than an upper surface of the first mask pattern; and
forming a second mask pattern on the first mask pattern, the second mask pattern extending in a second direction, and the second direction intersecting the first direction; and, wherein forming the second mask pattern on the first mask pattern comprises:
forming a second etching stop layer, a second sacrificial layer and a second hard mask layer sequentially stacked from bottom to top on the upper surface of the first filling layer;
patterning the second sacrificial layer and the second hard mask layer, to form a second sacrificial pattern, the second sacrificial pattern exposing the second etching stop layer;
forming a second initial mask pattern on side walls of the second sacrificial pattern; and
removing the second sacrificial pattern.