Semiconductor structure and method for forming the same

A semiconductor structure, comprising:

• an image sensor device, wherein the image sensor device comprises:
• a first substrate, wherein the first substrate comprises a first interconnect region and a pixel region;
• a photo-sensing region formed in the first substrate in the pixel region;
• a first oxide layer formed below the photo-sensing region;
• a first bonding layer formed below the first oxide layer;
• and
• a first bonding via formed through the first bonding layer and the first oxide layer;
• and
• a logic circuit device formed below the image sensor device, wherein the logic circuit device comprises:
• a second substrate, wherein the second substrate comprises a second interconnect region and a logic region;
• a transistor device formed over the second substrate;
• a second oxide layer formed over the transistor device;
• a second bonding layer formed over the second oxide layer;
• and
• a second bonding via formed through the second bonding layer and the second oxide layer in the second interconnect region;
• and
• the hybrid bonding structure between the image sensor device and the logic circuit device, and the hybrid bonding structure comprises the first bonding via bonded to the second bonding via.

A method for forming a semiconductor structure, comprising:

• forming a first semiconductor device, wherein the step of forming the first semiconductor device comprises:
• forming a first oxide layer over a first substrate, wherein the first substrate comprises a pixel region and a first interconnect region;
• forming a first bonding layer over the first oxide layer;
• forming a first recess in the first bonding layer in the pixel region;
• forming a first trench through the first bonding layer and the first oxide layer in the first interconnect region;
• filling a conductive material in the first recess and the first trench to form a first dummy pad and a first bonding via;
• forming a second semiconductor device, wherein the step of forming the second semiconductor device comprises:
• forming a second oxide layer over a second substrate, wherein the first substrate comprises a logic region and a second interconnect region;
• forming a second bonding layer over the second oxide layer;
• forming a second recess in the second bonding layer in the logic region;
• forming a second trench through the second bonding layer and the second oxide layer;
• filling the conductive material in the second recess and the second trench to form a second dummy pad and a second bonding via;
• and
• bonding the first semiconductor device and the second semiconductor device by bonding the first bonding via to the second bonding via, and bonding the first dummy pad to the second dummy pad.