US 12,136,568 B2
Semiconductor structure and method for forming same
Luguang Wang, Hefei (CN)
Assigned to CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed by CHANGXIN MEMORY TECHNOLOGIES, INC., Hefei (CN)
Filed on Jan. 26, 2022, as Appl. No. 17/648,964.
Application 17/648,964 is a continuation of application No. PCT/CN2021/109155, filed on Jul. 29, 2021.
Claims priority of application No. 202110357903.5 (CN), filed on Apr. 1, 2021.
Prior Publication US 2022/0319923 A1, Oct. 6, 2022
Int. Cl. H01L 23/48 (2006.01); H01L 21/768 (2006.01)
CPC H01L 21/76898 (2013.01) [H01L 21/7682 (2013.01); H01L 23/481 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A semiconductor structure, comprising:
a base, comprising a substrate and a dielectric layer, wherein the substrate has a front surface and a back surface that are oppositely arranged, and the dielectric layer is located on the front surface;
a connecting hole, penetrating the back surface of the substrate and extending to the dielectric layer;
a connecting structure, located in the connecting hole; and
an insulating structure, located between the connecting structure and an inner wall of the connecting hole,
wherein the connecting structure comprises a first conductive structure and a second conductive structure that are interconnected, the insulating structure comprises a first insulating layer and a second insulating layer, the first insulating layer is located between the inner wall of the connecting hole and the first conductive structure, and a distance from a surface of the first conductive structure to the back surface of the substrate is greater than a distance from a surface of the first insulating layer to the back surface of the substrate, the second insulating layer is located between the inner wall of the connecting hole and the second conductive structure, and the first insulating layer, the second insulating layer, the inner wall of the connecting hole and the connecting structure define an air gap, and
wherein the second insulating layer seals the air gap, or the second insulating layer and the second conductive structure jointly seal the air gap.