Bonding contacts having capping layer and method for forming the same

Abstract

In an example, a semiconductor device includes a first semiconductor structure including a memory array device, a second semiconductor structure including a peripheral device, and a bonding structure comprising a first bonding pad, a second bonding pad, and a remainder layer located between and in contact with the first and second bonding pad in a vertical direction. The first bonding pad is located between the remainder layer and the first semiconductor structure in the vertical direction. The second bonding pad is located between the remainder layer and the second semiconductor structure in the vertical direction. A conductive material of the remainder layer is cobalt metal different from the first and second bonding pads.

What is claimed is: 
     
         1 . A semiconductor device, comprising:
 a first semiconductor structure comprising a memory array device;   a second semiconductor structure comprising a peripheral device; and   a bonding structure comprising a first bonding pad, a second bonding pad, and a remainder layer located between and in contact with the first and second bonding pad in a vertical direction,   wherein the first bonding pad is located between the remainder layer and the first semiconductor structure in the vertical direction, and the second bonding pad is located between the remainder layer and the second semiconductor structure in the vertical direction; and   a conductive material of the remainder layer is cobalt metal different from the first and second bonding pads.   
     
     
         2 . The semiconductor device of  claim 1 , wherein a width of a surface of the second bonding pad in contact with the remainder layer is greater than a width of a surface of the first bonding pad in contact with the remainder layer in a lateral direction. 
     
     
         3 . The semiconductor device of  claim 2 , wherein a width of the remainder layer is greater than or equal to the width of the second bonding pad in contact with the remainder layer in the lateral direction. 
     
     
         4 . The semiconductor device of  claim 1 , wherein
 the remainder layer comprises a first remainder layer and a second remainder layer that are in contact with each other and are oppositely arranged in the vertical direction; and   the first remainder layer is in contact with the first bonding pad, and the second remainder layer is in contact with the second bonding pad.   
     
     
         5 . The semiconductor device of  claim 4 , wherein
 a width of the first remainder layer is greater than or equal to the width of a surface of the first bonding pad in contact with the first remainder layer in a lateral direction;   a width of the second remainder layer is greater than or equal to the width of a surface of the second bonding pad in contact with the second remainder layer in the lateral direction; and   the width of the second remainder layer is greater than the width of the first remainder layer in the lateral direction.   
     
     
         6 . The semiconductor device of  claim 1 , wherein the first or second bonding pad comprises copper. 
     
     
         7 . The semiconductor device of  claim 1 , wherein a thickness of the remainder layer is between about 1 nm and about 5 nm. 
     
     
         8 . The semiconductor device of  claim 1 , wherein
 the bonding structure comprises a first dielectric layer and a second dielectric layer; and   the first bonding pad is located in the first dielectric layer, and the second bonding pad is located in the second dielectric layer.   
     
     
         9 . The semiconductor device of  claim 8 , wherein a selectivity of the conductive material of the remainder layer is greater on the first or second bonding pad than on the first or second dielectric layer. 
     
     
         10 . The semiconductor device of  claim 8 , further comprising a first adhesion layer between the first bonding pad and the first dielectric layer, and a second adhesion layer between the second bonding pad and the second dielectric layer. 
     
     
         11 . The semiconductor device of  claim 1 , wherein
 at least one of the first bonding pad and the second bonding pad comprises a first end and a second end which are oppositely arranged in the vertical direction, and the first end is close to the remainder layer relative to the second end, and   a width of the first end is greater than a width of the second end in a lateral direction.   
     
     
         12 . A bonded structure, comprising:
 a first bonding pad;   a second bonding pad; and   a remainder layer located between and in contact with the first bonding pad and second bonding pad in a vertical direction,   wherein the first bonding pad includes a first surface in contact with the remainder layer and a second surface opposite to the first surface in the vertical direction; and   a width of the first surface is greater than a width of the second surface in a lateral direction.   
     
     
         13 . The bonded structure of  claim 12 , wherein a conductive material of the remainder layer is cobalt metal different from the first and second bonding pads. 
     
     
         14 . The bonded structure of  claim 12 , wherein the first or second bonding pad comprises copper. 
     
     
         15 . The bonded structure of  claim 12 , wherein
 the second bonding pad comprises a third surface in contact with the remainder layer and a fourth surface opposite to the third surface in the vertical direction, and   a width of the third surface is greater than the width of the first surface in the lateral direction, and a width of the remainder layer is greater than or equal to the width of the third surface in the lateral direction.   
     
     
         16 . The bonded structure of  claim 15 , wherein the width of the third surface is greater than a width of the fourth surface in the lateral direction. 
     
     
         17 . The bonded structure of  claim 12 , wherein
 the remainder layer comprises a first remainder layer and a second remainder layer which are in contact with each other and are oppositely arranged in the vertical direction;   the first remainder layer is in contact with the first bonding pad, and the second remainder layer is in contact with the second bonding pad;   a width of the first remainder layer is greater than or equal to the width of a surface of the first bonding pad in contact with the first remainder layer in a lateral direction;   a width of the second remainder layer is greater than or equal to the width of a surface of the second bonding pad in contact with the second remainder layer in the lateral direction; and   the width of the second remainder layer is greater than the width of the first remainder layer in the lateral direction.   
     
     
         18 . A semiconductor device, comprising:
 a first semiconductor structure comprising a memory array device;   a second semiconductor structure comprising a peripheral device; and   a bonding structure comprising a first dielectric layer and a first bonding pad located in the first dielectric layer, a second dielectric layer and a second bonding pad located in the second dielectric layer, and a remainder layer between the first bonding pad and the second bonding pad,   wherein the remainder layer is configured to prevent metal in the first bonding pad from diffusing to the second dielectric layer or to prevent metal in the second bonding pad from diffusing to the first dielectric layer.   
     
     
         19 . The semiconductor device of  claim 18 , wherein a selectivity of a conductive material of the remainder layer is greater on the first or second bonding pad than on the first or second dielectric layer. 
     
     
         20 . The semiconductor device of  claim 19 , wherein the conductive material of the remainder layer is cobalt metal different from the first and second bonding pads.