Semiconductor device and manufacturing method thereof

Abstract

A semiconductor device and a manufacturing method thereof are provided which can suppress corrosion by chemicals in processes, while preventing generation of thermal stress on a mark. A semiconductor device includes a semiconductor layer with front-side main surface and a back-side main surface opposed, to the front-side main surface, a plurality of light receiving elements formed in the semiconductor layer for performing photoelectric conversion, a light receiving lens disposed above the back-side main surface for supp_ying light to the light receiving element, and a mark formed inside the semiconductor layer. The mark extends from the front-side main surface to the back-side main surfaces The mark has a deeply located surface recessed toward the front-side main surface rather than the back-side main surface. The deeply located surface is formed of silicon.

1 - 15 . (canceled) 
     
     
         16 . A semiconductor device, comprising:
 a semiconductor layer with a front-side main surface and a back-side main surface opposed to the front-side main surface;   a plurality of light receiving elements formed in the semiconductor layer for performing photoelectric conversion;   a light receiving lens disposed above the back-side main surface of the semiconductor layer and supplying light to the light receiving element; and   a mark formed inside the semiconductor layer,   wherein the mark is formed from the front-side main surface to the back-side main surface in a trench extending through the semiconductor layer from the front-side main surface to the back-side main surface, and   wherein the mark includes:   a first mark component formed of a silicon nitride film in contact with an inner peripheral wall of the trench, and   a second mark component formed of a silicon oxide film to cover the first mark component in the trench.   
     
     
         17 . The semiconductor device according to  claim 16 , wherein the first mark component is disposed to be in contact with an end surface of the second mark component extending from the front-side main surface to the back-side main surface at a boundary between the second mark component and the back-side main surface.