US 12,310,003 B2
Semiconductor device and method of making the same
Pingheng Wu, Hefei (CN)
Assigned to CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Appl. No. 17/593,829
Filed by CHANGXIN MEMORY TECHNOLOGIES, INC., Anhui (CN)
PCT Filed Jun. 19, 2020, PCT No. PCT/CN2020/097170
§ 371(c)(1), (2) Date Sep. 24, 2021,
PCT Pub. No. WO2021/103505, PCT Pub. Date Jun. 3, 2021.
Claims priority of application No. 201911207283.6 (CN), filed on Nov. 29, 2019.
Prior Publication US 2022/0173110 A1, Jun. 2, 2022
Int. Cl. H10B 12/00 (2023.01); H01L 21/762 (2006.01); H10D 62/10 (2025.01)
CPC H10B 12/34 (2023.02) [H01L 21/762 (2013.01); H10B 12/053 (2023.02); H10B 12/488 (2023.02); H10D 62/115 (2025.01)] 17 Claims
OG exemplary drawing
 
1. A method for manufacturing a semiconductor device, comprising steps of:
providing a substrate comprising a shallow trench isolation region and an active region on a top surface;
forming trenches in the shallow trench isolation region and in the active region respectively, the trenches comprising a first trench located in the shallow trench isolation region and a second trench located in the active region, wherein a depth of the first trench is greater than or equal to a depth of the second trench, and a width of the first trench is greater than or equal to a width of the second trench;
forming a word line conductive layer on the substrate, wherein a part of the word line conductive layer is located in each of the trenches;
forming a first insulating thin film on the word line conductive layer in which an air gap structure is formed in the first insulating thin film by controlling a step coverage of the first insulating thin film; and
removing the first insulating thin film from the top surface of the substrate to form a first insulating layer, wherein the first insulating layer embeds the air gap structure; and
wherein the air gap structure is avoided to form above word line contact landing area, wherein the word line contact landing area refers to end of the word line conductive layer.