Semiconductor device and manufacturing method thereof

摘要

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 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 for supplying 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 surface. 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.

主权项

1. A manufacturing method of a semiconductor device, comprising the steps of:
providing a semiconductor substrate with a front-side main surface and an opposed main surface, which is opposed to the front-side main surface, said semiconductor substrate having an insulating layer embedded therein between the front-side main surface and the opposed main surface and a semiconductor layer between the front-side main surface and the insulating layer; forming a trench extending from the front-side main surface to a back-side of the semiconductor layer, the back-side of the semiconductor layer facing the insulating layer; forming a mark within the trench, said mark having a deeply located surface recessed with respect to the back-side of the semiconductor layer, said mark comprising at least a film of material that is the same as a material of said semiconductor layer; forming in the semiconductor layer a plurality of light receiving elements at the front-side main surface; removing a region of the semiconductor substrate that is between the opposed main surface and the back-side of the semiconductor layer; and disposing a light receiving lens for supplying light to one of the light receiving elements using the mark for alignment.