Semiconductor device and a manufacturing method thereof

A method for manufacturing a semiconductor device including a chip region,

• the method comprising the steps of:
• providing a semiconductor substrate having main surfaces;
• forming a photoelectric conversion element in the semiconductor substrate;
• forming a trench part extending from one of the main surfaces of the semiconductor substrate toward the other main surface side opposite to the one main surface, and for applying a light to the photoelectric conversion element;
• forming an insulation film covering the entire side surface of the trench part, and thereby forming a mark-like appearance part;
• forming a coupling part to be coupled with the mark-like appearance part;
• forming a pad electrode to be coupled with the coupling part at a position overlapping the the mark-like appearance part on the one main surface side of the semiconductor substrate;
• and
• forming an opening reaching the pad electrode from the other main surface side of the semiconductor substrate in such a manner as to expose at least a part of the other main surface side of the pad electrode,
• wherein the mark-like appearance part and the coupling part are formed in such a manner as to surround at least a part of the outer circumference of the opening in plan view.