Metal bonding structure and manufacturing method thereof

A method comprising:

• forming a first wafer that includes a first metal structure disposed within a body of the first wafer,
• wherein the first metal structure provides a first lattice structure within the body of the first wafer;
• forming a first set of recessed portions in a top surface of the first wafer;
• depositing a first plurality of metal elements within the first set of recessed portions;
• forming a second wafer including a second metal structure within a body of the second wafer,
• wherein the second metal structure provides a second lattice structure within the body of the second wafer;
• forming a second set of recessed portions in a top surface of the second wafer;
• depositing a second plurality of metal elements within the second set of recessed portions;
• depositing a solder bump on a first metal element, of the first plurality of metal elements, or a second metal element, the second plurality of metal elements;
• and
• bonding the top surface of the first wafer to the top surface of the second wafer,
• wherein the first plurality of metal elements are bonded to the second plurality of metal elements,
• wherein the first metal element is bonded to the second metal element via the solder bump, and
• wherein a third metal element, of the first plurality of metal elements, is bonded to a fourth metal element, of the second plurality of metal elements, without a solder bump.

A semiconductor structure comprising:

• a first wafer comprising:
• a first metal structure that provides a first lattice structure within a body of the first wafer;
• and
• a first plurality of metal elements extending between the first metal structure and a surface of the first wafer;
• and
• a second wafer comprising:
• a second metal structure that provides a second lattice structure within a body of the second wafer;
• and
• a second plurality of metal elements extending between the second metal structure and a surface of the second wafer,
• wherein the first wafer is coupled to the second wafer at an interface,
• wherein the first plurality of metal elements and the second plurality of metal elements form a metal bonding structure that extends from the first metal structure to the second metal structure through the interface,
• wherein a first metal element, of the first plurality of metal elements, is bonded to a second metal element, of the second plurality of metal elements, via a solder bump, and
• wherein a third metal element, of the first plurality of metal elements, is bonded to a fourth metal element, of the second plurality of metal elements, without a solder bump.