Semiconductor device and method for forming the same

A method for forming a semiconductor device, comprising:

• forming transistors over a front-side surface of a device substrate;
• forming a first interconnect structure over the transistors;
• forming an oxide layer and a bevel oxide over the device substrate;
• partially removing the oxide layer and the bevel oxide until a top surface of the oxide layer is substantially level with a top surface of the bevel oxide;
• attaching a carrier substrate to the oxide layer and the bevel oxide;
• and
• polishing a back-side surface of the device substrate,
• wherein the device substrate has a device recessed portion formed on the front-side surface.

A semiconductor device, comprising:

• a device layer;
• a front-side interconnect structure over a front-side surface of the device layer;
• a back-side interconnect structure over a back-side surface of the device layer;
• an oxide layer covering a central region of the front-side interconnect structure;
• and
• a bevel oxide covering a bevel region of the front-side interconnect structure,
• wherein the oxide layer and the bevel oxide are made of different dielectric materials.