Three-dimensional memory device and method for forming the same

A method for forming a three-dimensional (3D) memory device, comprising:

• forming a memory array structure over a first semiconductor layer;
• forming a second semiconductor layer over the memory array structure;
• after forming the second semiconductor layer over the memory array structure, forming a peripheral device in contact with the second semiconductor layer;
• and
• forming an interconnection layer over the peripheral device,
• wherein the second semiconductor layer is disposed between the peripheral device and the memory array structure.

A method for forming a three-dimensional (3D) memory device, comprising:

• forming a first dielectric layer over a first semiconductor layer;
• forming a memory array structure in the first dielectric layer;
• bonding a second semiconductor layer to the first dielectric layer, wherein the second semiconductor layer comprises a second dielectric layer, and the second dielectric layer is bonded to the first dielectric layer;
• forming a heterogeneous interface in the second semiconductor layer;
• removing a portion of the second semiconductor layer along the heterogeneous interface to form a third semiconductor layer over the memory array structure;
• forming a peripheral device in the third semiconductor layer;
• and
• forming an interconnection layer over the peripheral device,
• wherein the third semiconductor layer is disposed between the peripheral device and the memory array structure.