Three-dimensional memory device containing self-aligned interlocking bonded structure and method of making the same

A bonded structure comprising:

• a first substrate having a first bonding-side planar surface and a first mesa structure that protrudes from the first bonding-side planar surface, wherein the first mesa structure comprises a first metal pad structure containing a first metallic material and including a first metallic surface;
• a second substrate having a second bonding-side planar surface and a first recess cavity that is recessed from the second bonding-side planar surface, wherein a second metal pad structure comprising a second metallic material and including a second metallic surface is located at a recessed region of the first recess cavity, and the first mesa structure is disposed within a volume of the first recess cavity and the first bonding-side planar surface contacts the second bonding-side planar surface;
• and
• a metal connection pad comprising a third metallic material which is bonded to the first metal pad structure and the second metal pad structure, and which is located within a volume of the first recess cavity that is not filled by the first mesa structure;
• wherein:
• the first metallic surface is more proximal to a two-dimensional plane including an interface between the first bonding-side planar surface and the second bonding-side planar surface than a tip portion of the first mesa structure is to the two-dimensional plane;
• and
• the second metallic surface is more distal from the two-dimensional plane than a recessed planar surface of the first recess cavity that is parallel to the two-dimensional plane.

A bonded structure comprising:

• a first substrate having a first bonding-side planar surface and a first mesa structure that protrudes from the first bonding-side planar surface, wherein the first mesa structure comprises a first metal pad structure containing a first metallic material and including a first metallic surface;
• a second substrate having a second bonding-side planar surface and a first recess cavity that is recessed from the second bonding-side planar surface, wherein a second metal pad structure comprising a second metallic material and including a second metallic surface is located at a recessed region of the first recess cavity, and the first mesa structure is disposed within a volume of the first recess cavity and the first bonding-side planar surface contacts the second bonding-side planar surface;
• and
• a metal connection pad comprising a third metallic material which is bonded to the first metal pad structure and the second metal pad structure, and which is located within a volume of the first recess cavity that is not filled by the first mesa structure;
• wherein:
• the first metallic material comprises a first metal nitride material;
• the second metallic material comprises a second metal nitride material;
• and
• the third metallic material comprises a material selected from tungsten, ruthenium, and cobalt.

A bonded structure comprising:

• a first substrate having a first bonding-side planar surface and a first mesa structure that protrudes from the first bonding-side planar surface, wherein the first mesa structure comprises a first metal pad structure containing a first metallic material and including a first metallic surface;
• a second substrate having a second bonding-side planar surface and a first recess cavity that is recessed from the second bonding-side planar surface, wherein a second metal pad structure comprising a second metallic material and including a second metallic surface is located at a recessed region of the first recess cavity, and the first mesa structure is disposed within a volume of the first recess cavity and the first bonding-side planar surface contacts the second bonding-side planar surface;
• a metal connection pad comprising a third metallic material which is bonded to the first metal pad structure and the second metal pad structure, and which is located within a volume of the first recess cavity that is not filled by the first mesa structure;
• first semiconductor devices located over a front side of the first substrate;
• and
• second semiconductor devices located over a front side of the second substrate.

A bonded structure comprising:

• a first substrate having a first bonding-side planar surface and a first mesa structure that protrudes from the first bonding-side planar surface, wherein the first mesa structure comprises a first metal pad structure containing a first metallic material and including a first metallic surface;
• a second substrate having a second bonding-side planar surface and a first recess cavity that is recessed from the second bonding-side planar surface, wherein a second metal pad structure comprising a second metallic material and including a second metallic surface is located at a recessed region of the first recess cavity, and the first mesa structure is disposed within a volume of the first recess cavity and the first bonding-side planar surface contacts the second bonding-side planar surface;
• and
• a metal connection pad comprising a third metallic material which is bonded to the first metal pad structure and the second metal pad structure, and which is located within a volume of the first recess cavity that is not filled by the first mesa structure;
• wherein:
• the first substrate comprises a second recess cavity that is recessed from the first bonding-side planar surface, wherein a third metal pad structure including a third metallic surface is located at a recessed region of the second recess cavity;
• the second substrate comprises a second mesa structure that protrudes from the second bonding-side planar surface, wherein the second mesa structure comprises a fourth metal pad structure including a fourth metallic surface, and the second mesa structure is disposed within a volume of the second recess cavity;
• and
• another metal connection pad comprising the third metallic material is bonded to the third metal pad structure and the fourth metal pad structure, and is located within a volume of the second recess cavity that is not filled by the second mesa structure.