Semiconductor device

A semiconductor device, comprising:

• an upper pad;
• an upper dielectric layer that surrounds the upper pad, the upper dielectric layer extends in a first direction and a second direction that intersects the first direction;
• a lower pad in contact with the upper pad and the upper dielectric layer;
• and
• a lower dielectric layer that surrounds the lower pad and contacts the upper pad and the upper dielectric layer, the lower dielectric layer extends in the first direction and the second direction,
• wherein the upper pad, the upper dielectric layer, the lower pad, and the lower dielectric layer define an upper space that surrounds a lower portion of the upper pad and a lower space that surrounds an upper portion of the lower pad,
• wherein the upper space includes a first pad overlap section that overlaps the lower pad in a third direction that intersects the first direction and the second direction, and a first dielectric layer overlap section that overlaps the lower dielectric layer in the third direction,
• wherein the lower pad includes a first surface in contact with the upper dielectric layer and a second surface in contact with the upper pad,
• wherein the first pad overlap section is between the first surface and the second surface of the lower pad,
• wherein the first and second surfaces of the lower pad are flat, and
• wherein the lower pad further includes a protrusion part that protrudes between the first surface and the second surface of the lower pad.

A semiconductor device, comprising:

• a first substrate that extends in a first direction and a second direction that intersects the first direction;
• a second substrate spaced apart from the first substrate and that extends in the first direction and the second direction;
• a lower pad electrically connected to the first substrate;
• a lower dielectric layer that surrounds the lower pad;
• an upper pad electrically connected to the second substrate and in contact with the lower pad and the lower dielectric layer;
• and
• an upper dielectric layer that surrounds the upper pad and contacts the lower pad and the lower dielectric layer,
• wherein the upper pad, the upper dielectric layer, the lower pad, and the lower dielectric layer define an upper space that surrounds a lower portion of the upper pad and a lower space that surrounds an upper portion of the lower pad,
• wherein the upper space includes a first pad overlap section that overlaps the lower pad in a third direction that intersects the first direction and the second direction, and a first dielectric layer overlap section that overlaps the lower dielectric layer in the third direction,
• wherein the lower space includes a second pad overlap section that overlaps the upper pad in the third direction and a second dielectric layer overlap section that overlaps the upper dielectric layer in the third direction,
• wherein the lower pad includes a first protrusion part that protrudes toward the first pad overlap section,
• wherein the upper pad includes a second protrusion part that protrudes toward the second pad overlap section,
• wherein the first protrusion part is at a level higher than a level of a top surface of the lower dielectric layer in the third direction,
• wherein the second protrusion part is at a level lower than a level of a bottom surface of the upper dielectric layer in the third direction,
• wherein the upper pad includes a first surface in contact with the lower dielectric layer and a second surface in contact with the lower pad, and
• wherein the second protrusion part protrudes between the first surface and the second surface of the upper pad.