Solid-state imaging device and method for manufacturing the same

Abstract

The solid-state imaging device according to one embodiment of the present invention includes a semiconductor substrate, a plurality of photoelectric conversion regions arrayed in the vertical direction and the horizontal direction on the surface of the substrate, and an electric charge transfer region disposed between the photoelectric conversion regions adjacent in the horizontal direction of the substrate. The substrate comprises a n-type semiconductor substrate, a first p-type impurity region formed on the n-type semiconductor substrate, a semiconductor regions formed on the first p-type impurity region, and a second p-type impurity region disposed below the electric charge transfer region. The photoelectric conversion region and the electric charge transfer region are n-type impurity regions formed on the surface portion of the semiconductor region. A third p-type impurity region is formed in at least one region selected from the group consisting of a region located between the photoelectric conversion regions adjacent in the vertical direction and a region located below the second p-type impurity region between the photoelectric conversion regions adjacent in the horizontal direction in the semiconductor region.

1 - 11 . (Cancelled).  
     
     
         12 . A method for manufacturing a solid-state imaging device comprising a semiconductor substrate, a plurality of photoelectric conversion regions arrayed in the vertical direction and the horizontal direction on the surface of the substrate, and an electric charge transfer region disposed between the photoelectric conversion regions adjacent in the horizontal direction of the substrate; the method comprising: 
 forming a first p-type impurity region and a semiconductor region on a n-type semiconductor substrate in this order;    forming the photoelectric conversion region that is a n-type impurity region and the electric charge transfer region that is a n-type impurity region on the surface portion of the semiconductor region;    forming a second p-type impurity region below the electric charge transfer region; and    forming a third p-type impurity region is formed in at least one region selected from the group consisting of a region located between the photoelectric conversion regions adjacent in the vertical direction and a region located below the second p-type impurity region between the photoelectric conversion regions adjacent in the horizontal direction in the semiconductor region.    
     
     
         13 . The method for manufacturing a solid-state imaging device according to  claim 12 , wherein the third p-type impurity region is formed by ion-implanting p-type impurities into the semiconductor region, followed by diffusing the p-type impurities up to the deep part of the substrate by heat treatment.  
     
     
         14 . The method for manufacturing a solid-state imaging device according to  claim 13 , wherein the acceleration voltage of the ion-implantation is in the range from 1 MeV to 2 MeV.  
     
     
         15 . The method for manufacturing a solid-state imaging device according to  claim 14 , wherein the third p-type impurity region is formed by implanting the p-type impurities into the semiconductor region by carrying out ion-implantation plural times by varying the acceleration voltage.  
     
     
         16 . The method for manufacturing a solid-state imaging device according to  claim 15 , wherein the acceleration voltage of the ion-implantation is in the range from 1 MeV to 4 MeV.  
     
     
         17 . The method for manufacturing a solid-state imaging device according to  claim 15 , wherein plural ion-implantations can be carried out so that the ion-implantation at higher acceleration voltage is carried out at smaller dose amount.  
     
     
         18 . The method for manufacturing a solid-state imaging device according to  claim 12 , further comprising forming a fourth p-type impurity region between the photoelectric conversion regions adjacent in the vertical direction on the surface portion of the semiconductor region.  
     
     
         19 . The method for manufacturing a solid-state imaging device according to  claim 18 , wherein the impurity concentration of the third p-type impurity region is set to be lower than the impurity concentration of the fourth p-type impurity region.  
     
     
         20 . A method for manufacturing a solid-state imaging device comprising a semiconductor substrate, a plurality of photoelectric conversion regions arrayed in the vertical direction and the horizontal direction on the surface of the substrate, and an electric charge transfer region disposed between the photoelectric conversion regions adjacent in the horizontal direction of the substrate; the method comprising: 
 forming a first type impurity region of a second conductivity type and a semiconductor region on a first′ conductivity type semiconductor substrate in this order;    forming the photoelectric conversion region that is a first conductivity type impurity region and the electric charge transfer region that is a first conductivity type impurity region on the surface portion of the semiconductor region;    forming a second impurity region of the second conductivity type below the electric charge transfer region; and    forming a third impurity region of the second conductivity type in at least one region selected from the group consisting of a region located between the photoelectric conversion regions adjacent in the vertical direction and a region located below the second impurity region of the second conductivity type between the photoelectric conversion regions adjacent in the horizontal direction in the semiconductor region.    
     
     
         21 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein the third impurity region of the second conductivity type is formed by ion-implanting second conductivity type impurities into the semiconductor region, followed by diffusing the second conductivity type impurities up to the deep part of the substrate by heat treatment.  
     
     
         22 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein the acceleration voltage of the ion-implantation is in the range from 1 MeV to 2 MeV.  
     
     
         23 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein the third impurity region of the second conductivity type is formed by implanting the second conductivity type impurities into the semiconductor region by carrying out ion-implantation plural times by varying the acceleration voltage.  
     
     
         24 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein the acceleration voltage of the ion-implantation is in the range from 1 MeV to 4 MeV.  
     
     
         25 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein plural ion-implantations can be carried out so that the ion-implantation at higher acceleration voltage is carried out at smaller dose amount.  
     
     
         26 . The method for manufacturing a solid-state imaging device according to  claim 20 , further comprising forming a fourth impurity region of the second conductivity type between the photoelectric conversion regions adjacent in the vertical direction on the surface portion of the semiconductor region.  
     
     
         27 . The method for manufacturing a solid-state imaging device according to  claim 20 , wherein the impurity concentration of the third impurity region of the second conductivity type is set to be lower than the impurity concentration of the forth impurity region of the second conductivity type.