Auto-focus image sensor and digital image processing device including the same

Abstract

The inventive concepts provide an auto-focus image sensor and a digital image processing device including the same. The auto-focus image sensor includes a substrate including at least one first pixel used for detecting a phase difference and at least one second pixel used for detecting an image, a deep device isolation portion disposed in the substrate to isolate the first pixel from the second pixel, and a light shielding pattern disposed on the substrate of at least the first pixel. The amount of light incident on the first pixel is smaller than the amount of light incident on the second pixel by the light shielding pattern.

What is claimed is: 
     
         1 . An Image sensor comprising:
 a substrate including a plurality of pixels, the plurality of pixels comprising
 a first plurality of auto-focus pixels arranged in a first line along a first direction; and 
 a second plurality of auto-focus pixels arranged in a second line along a second direction perpendicular to the first direction, 
   wherein the first plurality of auto-focus pixels including a first AF pixel covered by a first light shield and a second AF pixel covered by a second light shield,   wherein the second plurality of auto-focus pixels including a third AF pixel covered by a third light shield and a fourth AF pixel covered by a fourth light shield,   wherein the first light shield is disposed on first and second quadrants of the first AF pixel so that a first opening is formed at third and fourth quadrants of the first AF pixel,   wherein the second light shield is disposed on third and fourth quadrants of the second AF pixel so that a second opening is formed at first and second quadrants of the second AF pixel,   wherein the third light shield is disposed on second and third quadrants of the third AF pixel so that a third opening is formed at first and fourth quadrants of the third AF pixel, and   wherein the fourth light shield is disposed on first and fourth quadrants of the fourth AF pixel so that a fourth opening is formed at second and third quadrants of the fourth AF pixel.   
     
     
         2 . The image sensor of  claim 1 , wherein the plurality of pixels further comprises a plurality of image pixels to generate an image signal, and
 wherein each of the plurality of image pixels has a fifth opening bigger than each of the first to the fourth openings.   
     
     
         3 . The image sensor of  claim 2 , wherein each of the first to fourth AF pixels includes the first to fourth quadrants,
 the first and second quadrants are adjacent to each other in the second direction,   the third and fourth quadrants are adjacent to each other in the second direction,   the second and third quadrants are adjacent to each other in the first direction, and   the first and fourth quadrants are adjacent to each other in the first direction.   
     
     
         4 . The image sensor of  claim 3 , further comprising an isolation structure formed in the substrate and between adjacent ones of the plurality of pixels. 
     
     
         5 . The image sensor of  claim 4 , wherein the substrate having a first surface on which a gate electrode is disposed and a second surface opposite to the first surface, and
 wherein the isolation structure extends from the second surface to the first surface.   
     
     
         6 . The image sensor of  claim 5 , wherein the isolation structure includes a fixed charge layer and an insulation layer. 
     
     
         7 . The image sensor of  claim 6 , wherein the isolation structure further includes an air gap surrounded by the fixed charge layer. 
     
     
         8 . The image sensor of  claim 5 , further comprising a green color filter corresponding to each of the first to fourth AF pixels. 
     
     
         9 . The image sensor of  claim 5 , wherein the first plurality of auto-focus pixels are commonly coupled to a signal sensing line. 
     
     
         10 . The image sensor of  claim 9 , wherein the second plurality of auto-focus pixels commonly coupled to a selection line. 
     
     
         11 . The image sensor of  claim 2 , wherein total area of the first to fourth openings of the first to fourth AF pixels is about 50% of total area of the fifth openings of the plurality of image pixels. 
     
     
         12 . The image sensor of  claim 5 , further comprising a light shielding pattern overlapping on the isolation structure and having a mesh shape. 
     
     
         13 . The image sensor of  claim 12 , wherein the light shielding pattern is connected to the first to the fourth light shields. 
     
     
         14 . The image sensor of  claim 1 , further comprising at least three consecutive pixels of the plurality of pixels disposed between the first AF pixel and the second AF pixel. 
     
     
         15 . The image sensor of  claim 14 , wherein a middle of the at least three consecutive pixels is connected to a selection line to which the third AF and the fourth AF are connected. 
     
     
         16 . The image sensor of  claim 15 , further comprising a green color filter corresponding to at least one of the at least three consecutive pixels. 
     
     
         17 . An Image sensor comprising:
 a substrate including a plurality of pixels, the plurality of pixels comprising
 a first plurality of auto-focus pixels arranged in a first line along a first direction; 
 a second plurality of auto-focus pixels arranged in a second line along a second direction perpendicular to the first direction; and 
   a light shielding pattern on the substrate of the first and second plurality of auto-focus pixels,   wherein the first plurality of auto-focus pixels including a first AF pixel and a second AF pixel,   wherein the second plurality of auto-focus pixels including a third AF pixel and a fourth AF pixel,   wherein each of the first and second AF pixels includes top and bottom parts symmetric to each other in the first direction,   wherein each of the third and fourth AF pixels includes left and right parts symmetric to each other in the second direction, and   wherein the light shielding pattern has a first opening on the bottom part of the first AF pixel, a second opening on the top part of the second AF pixel, a third opening on the right part of the third AF pixel, and a fourth opening on the left part of the fourth AF pixel.   
     
     
         18 . The image sensor of  claim 17 , wherein the plurality of pixels further comprises a plurality of image pixels to generate an image signal,
 wherein the light shielding pattern has a fifth opening corresponding to each of the plurality of image pixels, and   the fifth opening is bigger than each of the first to the fourth openings.   
     
     
         19 . The image sensor of  claim 18 , wherein an area of each of the first to fourth openings is about 50% of an area of the fifth opening. 
     
     
         20 . The image sensor of  claim 17 , further comprising a green color filter corresponding to each of the first to fourth AF pixels.