Method of manufacturing semiconductor device

摘要

Provided is a semiconductor device having improved performance and an improved manufacturing yield. Over photodiodes formed in a semiconductor substrate, a plurality of first to third embedded insulating films are stacked to form a waveguide for light incident on each of the photodiodes. The first embedded insulating film is formed simultaneously with plugs when the plugs are formed. The second embedded insulating film is formed simultaneously with first wires when the first wires are formed. The third embedded insulating film is formed simultaneously with second wires when the second wires are formed.

主权项

1. A method of manufacturing a semiconductor device, comprising the steps of:
(a) providing a semiconductor substrate; (b) forming a light receiving element in the semiconductor substrate; (c) after the step (b), forming a first interlayer insulating film over the semiconductor substrate; (d) forming a first opening in the first interlayer insulating film; (e) forming a first metal film over the first interlayer insulating film so as to fill the first opening therewith; (f) forming a second opening in the first metal film; (g) etching the first interlayer insulating film exposed from the second opening to form a third opening in the first interlayer insulating film; (h) forming a first insulating film over the first metal film so as to fill the third opening and the second opening therewith; (i) polishing the first insulating film and the first metal film to remove the first metal film located outside the first opening and the first insulating film located outside the third opening to leave the first metal film in the first opening and leave the first insulating film in the third opening; (j) after the step (i), forming a second interlayer insulating film over the first interlayer insulating film; (k) forming a fourth opening in the second interlayer insulating film; (l) forming a second metal film over the second interlayer insulating film so as to fill the fourth opening therewith; (m) forming a fifth opening in the second metal film; (n) etching the second interlayer insulating film exposed from the fifth opening to form a sixth opening in the second interlayer insulating film; (o) forming a second insulating film over the second metal film so as to fill the sixth opening and the fifth opening therewith; and (p) polishing the second insulating film and the second metal film to remove the second metal film located outside the fourth opening and the second insulating film located outside the sixth opening to leave the second metal film in the fourth opening and leave the second insulating film in the sixth opening, wherein the first insulating film embedded in the third opening in the step (i) is located over the light receiving element, wherein the second insulating film embedded in the sixth opening in the step (p) is located over the first insulating film embedded in the third opening in the step (i), and wherein the second insulating film embedded in the sixth opening in the step (p) and the first insulating film embedded in the third opening in the step (i) function as a waveguide for light incident on the light receiving element.