Cmos image sensor and method of manufacturing same

Abstract

Disclosed are a complementary metal oxide semiconductor (CMOS) image sensor and a method of forming the same. The CMOS image sensor comprises a semiconductor substrate having a photodiode region and a transistor region. An optical path is formed between a micro lens on the photodiode region and a photodiode formed on the semiconductor substrate. The optical path comprises an inner lens formed between an intermetal insulation layer on the photodiode region and a transparent optical region formed on the inner lens. The transparent optical region generally has a different refractive index from the inner lens.

1 . A complementary metal oxide semiconductor (CMOS) image sensor, comprising: 
 a substrate having a photodiode region and a transistor region;    a photodiode formed in the photodiode region;    a transistor formed in the transistor region;    a planarized insulation layer covering the photodiode and the plurality of transistors;    an intermetal insulation layer formed from a first material on the planarized insulation layer;    a metal wire layer formed on the transistor region at least partially within the intermetal insulation layer;    an inner lens formed on the planarized insulation layer over the photodiode as part of the intermetal insulation layer; and,    a transparent optical region formed from a second material different from the first material and formed at least partially within the intermetal insulation layer over the inner lens.    
   
   
       2 . The CMOS image sensor of  claim 1 , wherein the inner lens is a convex lens.  
   
   
       3 . The CMOS image sensor of  claim 1 , wherein the inner lens is a concave lens.  
   
   
       4 . The CMOS image sensor of  claim 1 , wherein the intermetal insulation layer comprises a film formed from at least one material selected from a group consisting of an oxide and a nitride.  
   
   
       5 . The CMOS image sensor of  claim 4 , wherein the inner lens is formed from an oxide film.  
   
   
       6 . The CMOS image sensor of  claim 1 , wherein the transparent optical region is formed from a material having a different refractive index from that of the inner lens.  
   
   
       7 . The CMOS image sensor of  claim 6 , wherein the inner lens is a convex lens and the transparent optical region is formed of a material having a lower refractive index than the inner lens.  
   
   
       8 . The CMOS image sensor of  claim 6 , wherein the inner lens is a concave lens and the transparent optical region is formed of a material having a higher refractive index than the inner lens.  
   
   
       9 . The CMOS image sensor of  claim 6 , wherein the inner lens is formed of an oxide film and the transparent optical region is formed of an organic polymer compound.  
   
   
       10 . The CMOS image sensor of  claim 1 , further comprising: 
 a transparent optical liner formed between the inner lens and the transparent optical region.    
   
   
       11 . The CMOS image sensor of  claim 10 , where in the transparent optical liner is formed of a material having a different refractive index from the inner lens and the transparent optical region.  
   
   
       12 . The CMOS image sensor of  claim 11 , wherein the transparent optical liner is formed of a silicon nitride, a silicon oxide-nitride, or an organic polymer compound.  
   
   
       13 . The CMOS image sensor of  claim 10 , wherein the inner lens is formed of an oxide film, the transparent optical liner is formed of a silicon nitride, a silicon oxide-nitride, or an organic polymer compound, and the transparent optical region is formed of an organic polymer compound.  
   
   
       14 . The CMOS image sensor of  claim 10 , wherein the inner lens is a convex lens and the transparent optical liner is formed with a convex shape on an upper surface of the inner lens.  
   
   
       15 . The CMOS image sensor of  claim 14 , wherein the transparent optical liner has lower refractive index than the inner lens and the transparent optical region has a lower refractive index than the transparent optical liner.  
   
   
       16 . The CMOS image sensor of  claim 10 , wherein the inner lens is a concave lens and the transparent optical liner is formed with a concave shape on an upper surface of the inner lens.  
   
   
       17 . The CMOS image sensor of  claim 16 , wherein the transparent optical liner has a higher refractive index than the inner lens and the transparent optical region has a higher refractive index than the transparent optical liner.  
   
   
       18 . The CMOS image sensor of  claim 18 , wherein the inner lens is formed on a common plane with the metal wire layer.  
   
   
       19 . The CMOS image sensor of  claim 1 , further comprising: 
 a color filter formed on the transparent optical region; and,    a micro lens formed on the color filter and opposite the photodiode.    
   
   
       20 . The CMOS image sensor of  claim 19 , further comprising a planarized layer covering the metal wire layer and the transparent optical region; 
 wherein the color filter is formed on the planarized layer.    
   
   
       21 . The CMOS image sensor of  claim 20 , wherein the planarized layer is formed of the same material as the transparent optical region.