Solid-state imaging device, method for manufacturing solid-state imaging device, and electronic apparatus

Abstract

A solid-state imaging device including a light-receiving portion, which serves as a pixel, and a waveguide, which is disposed at a location in accordance with the light-receiving portion and which includes a clad layer and a core layer embedded having a refractive index distribution in the wave-guiding direction.

1 . A method for manufacturing a solid-state imaging device comprising the steps of:
 forming a clad layer on a light-receiving portion serving as a pixel; and   embedding a core layer, which has a refractive index distribution in a wave-guiding direction, into a trench portion surrounded by the clad layer,   wherein,
 the clad layer and the core layer constitute the waveguide. 
   
     
     
         2 . The method for manufacturing a solid-state imaging device according to  claim 1 , wherein in the embedding the core layer:
 a high density plasma film formation method is used,   the D/S ratio is controlled, where D represents a deposition rate and S represents a sputtering rate,   a first film exhibiting high embeddability and having a low refractive index is embedded on the bottom side of the trench portion, and   a second film having a refractive index higher than that of the first film is embedded on the first film.   
     
     
         3 . The method for manufacturing a solid-state imaging device according to  claim 1 , wherein in the embedding the core layer:
 a high density plasma film formation method is used,   gases selected from the group consisting of silane based gases, N 2 , O 2 , TEOS, ammonia, argon, trimethylsilane, tetramethylsilane, and the like are used,   the ratio and the flow rate of the gases are controlled, and   a SiON film, a SiN film, or a SiC film is embedded selectively so as to form the core layer.   
     
     
         4 . The method for manufacturing a solid-state imaging device according to  claim 3 , wherein the first film is formed from a plurality of films having different refractive indices. 
     
     
         5 . The method for manufacturing a solid-state imaging device according to  claim 3 , wherein the first film is formed from a film in which the refractive index is changed continuously. 
     
     
         6 . The method for manufacturing a solid-state imaging device according to  claim 1 , the method further comprising the step of:
 forming an antireflection film on the surface of the light-receiving portion before the forming a clad layer,   wherein,
 the core layer is embedded in such a way as to come into contact with the antireflection film. 
   
     
     
         7 . The method for manufacturing a solid-state imaging device according to  claim 2 , the method further comprising the step of:
 forming an intra-layer lens on the second film after the second film serving as the core layer is formed.   
     
     
         8 . The method for manufacturing a solid-state imaging device according to  claim 1 , wherein the embedding a core layer comprising the steps of:
 embedding a first film into the trench portion surrounded by the clad layer by a high density plasma film formation method; and   forming a second film having a refractive index higher than that of the first film on the first film by a parallel plate plasma CVD method.   
     
     
         9 . The method for manufacturing a solid-state imaging device according to  claim 8 , the method further comprising the step of:
 forming an intra-layer lens on the second film after the second film serving as the core layer is formed.   
     
     
         10 . The method for manufacturing a solid-state imaging device according to  claim 1 , the method further comprising the step of:
 forming an antireflection film, which has a refractive index higher than that of the clad layer, on the surface of the light-receiving portion before the forming a clad layer,   wherein,
 the clad layer is formed in such a way as to present on the antireflection film.