Semiconductor devices including bonded semiconductor layers and manufacturing methods of the same

A manufacturing method of a semiconductor device, the method comprising:

• preparing a first semiconductor layer including a wire and an electrical element, wherein a plurality of metal pads is on a surface of the first semiconductor layer;
• and
• stacking and bonding a second semiconductor layer on the surface of the first semiconductor layer,
• wherein the plurality of metal pads includes a first metal pad and a second metal pad,
• wherein the second metal pad is smaller in surface area or diameter on the surface of the first semiconductor layer than the first metal pad, and
• wherein the second metal pad is between a first region of the surface of the first semiconductor layer where the first metal pad is and a second region of the surface of the first semiconductor layer where a surface metal density is zero (0).

A semiconductor device comprising:

• a silicon interposer;
• a memory that includes a plurality of semiconductor chip dies stacked on the silicon interposer;
• and
• a logic circuit on the silicon interposer, wherein the logic circuit includes a central processing unit or a graphics processing unit,
• wherein at least one of the silicon interposer, the plurality of semiconductor chip dies, and the logic circuit includes a plurality of metal pads on a surface thereof,
• wherein the plurality of metal pads includes a first metal pad and a second metal pad,
• wherein the second metal pad is smaller in surface area or diameter on the surface than the first metal pad, and
• wherein the second metal pad is between a first region of the surface where the first metal pad is and a second region of the surface where a surface metal density is zero (0).