Image pickup device and method of manufacturing the same

Abstract

To prevent deterioration in the sensitivity of a pixel part caused by variation in the distance between a waveguide and a photo diode and by decay of light due to suppression of reflection of entering light. In a pixel region, there is formed a waveguide which penetrates through a fourth interlayer insulating film or the like and reaches a sidewall insulating film. The sidewall insulating film is configured to have a stacked structure of a silicon oxide film and a silicon nitride film. The waveguide is formed so as to penetrate through even the silicon nitride film of the sidewall insulating film and to reach the silicon oxide film of the sidewall insulating film, or so as to reach the silicon nitride film of the sidewall.

What is claimed is: 
     
         1 . An image pickup device, comprising:
 a photo diode for converting entering light into a charge formed in a semiconductor substrate;   a transfer transistor for transferring the charge generated in the photo diode;   a gate electrode of the transfer transistor formed over the semiconductor substrate;   a sidewall insulating film covering a side wall face of the gate electrode and covering a surface of the photo diode;   a liner film formed over the side wall film and covering the gate electrode;   an interlayer insulating film formed over the liner film;   a plurality of wiring layers formed in the interlayer insulating film and not located over the photo diode in a planar view; and   a waveguide penetrating through the interlayer insulating film and the liner film and located over the photo diode in a planar view,   wherein a bottom of the waveguide penetrates is located in the sidewall insulating film.   
     
     
         2 . The image pickup device according to the  claim 1 ,
 wherein the sidewall insulating film includes:   a first silicon oxide film; and   a first silicon nitride film formed between the first silicon oxide film and the liner film, and   wherein the waveguide is formed so as to penetrate through the first silicon nitride film and to reach the first silicon oxide film.   
     
     
         3 . The image pickup device according to the  claim 2 ,
 wherein the liner film includes a second silicon nitride film.   
     
     
         4 . The image pickup device according to the  claim 1 ,
 wherein the sidewall insulating film includes:   a first silicon oxide film; and   a first silicon nitride film formed between the first silicon oxide film and the liner film, and   wherein the bottom of the waveguide is located in the silicon nitride film.   
     
     
         5 . The image pickup device according to the  claim 1 ,
 wherein the photo diode includes:   a p-type impurity region formed in the semiconductor substrate, and   an n-type impurity region formed in the p-type impurity region.   
     
     
         6 . The image pickup device according to the  claim 1 ,
 wherein the waveguide includes:   a protective film covering a surface of an opening part penetrating through the interlayer insulating film; and   an embedding member filling the opening part covered with the protective film.   
     
     
         7 . The image pickup device according to the  claim 6 ,
 wherein the protective film is a silicon nitride film; and   wherein the embedding member is a coating-based material.   
     
     
         8 . The image pickup device according to the  claim 1 ,
 wherein the waveguide includes a predetermined film filling an opening part penetrating through the interlayer insulating film.   
     
     
         9 . The image pickup device according to the  claim 8 ,
 wherein the predetermined film is a silicon nitride film.   
     
     
         10 . The image pickup device according to the  claim 1 ,
 wherein each of the wiring layer includes an aluminum film