Imaging element

Abstract

The present technology relates to an imaging element that can increase the degree of freedom of element arrangement. A photoelectric conversion unit, a through trench penetrating a semiconductor substrate in a depth direction and formed between pixels each including the photoelectric conversion unit, and a PN junction region in a side wall of the trench are included, and the through trench has an opening portion, and a P-type region is formed in the opening portion. A photoelectric conversion unit, a holding unit, a through trench formed between the photoelectric conversion unit and the holding unit, and a PN junction region in a side wall of the through trench are included, and the through trench has an opening portion and a readout gate for reading the charge from the photoelectric conversion unit is formed in the opening portion. The present technology can be applied to, for example, an imaging element.

What is claimed is: 
     
         1 . An imaging element comprising:
 a photoelectric conversion unit configured to perform photoelectric conversion;   a through trench penetrating a semiconductor substrate in a depth direction and formed between pixels each including the photoelectric conversion unit; and   a PN junction region configured by a P-type region and an N-type region in a side wall of the through trench, wherein   the through trench partially has an opening portion, and the P-type region is formed in the opening portion.   
     
     
         2 . The imaging element according to  claim 1 , wherein
 the opening portion is formed at least one corner of four corners of the pixel.   
     
     
         3 . The imaging element according to  claim 1 , wherein
 a contact region for fixing a potential is formed in at least one pixel of a plurality of pixels that is electrically conductive by the opening portion.   
     
     
         4 . The imaging element according to  claim 3 , wherein
 the electrically conductive pixels are pixels having a green color filter.   
     
     
         5 . The imaging element according to  claim 1 , wherein
 a light shielding film for covering the opening portion is formed on a light incident surface side of the opening portion.   
     
     
         6 . The imaging element according to  claim 1 , wherein
 a non-through trench is formed in the opening portion.   
     
     
         7 . The imaging element according to  claim 1 , wherein
 the P-type region of the opening portion is formed in a region sandwiched by non-through trenches.   
     
     
         8 . The imaging element according to  claim 1 , wherein
 the through trench is formed in an element isolation region.   
     
     
         9 . The imaging element according to  claim 1 , wherein
 the P-type region and an active region are formed in the opening portion.   
     
     
         10 . The imaging element according to  claim 9 , wherein
 a contact region for fixing a potential is formed in the opening portion.   
     
     
         11 . The imaging element according to  claim 1 , wherein
 the opening portion is formed in a side of the pixel.   
     
     
         12 . The imaging element according to  claim 11 , wherein
 the through trench formed in the opening portion is formed in a T shape.   
     
     
         13 . The imaging element according to  claim 11 , wherein
 the P-type region formed in the opening portion is formed larger than the P-type region formed in a portion other than the opening portion.   
     
     
         14 . The imaging element according to  claim 11 , wherein
 a floating diffusion (FD) region is formed in the opening portion.   
     
     
         15 . An imaging element comprising:
 a photoelectric conversion unit configured to perform photoelectric conversion;   a holding unit configured to hold a charge transferred from the photoelectric conversion unit;   a through trench penetrating a semiconductor substrate in a depth direction and formed between the photoelectric conversion unit and the holding unit; and   a PN junction region configured by a P-type region and an N-type region in a side wall of the through trench, wherein   the through trench partially has an opening portion, and a readout gate for reading the charge from the photoelectric conversion unit is formed in the opening portion.   
     
     
         16 . The imaging element according to  claim 15 , wherein
 the readout gate is formed in a vertical direction and a horizontal direction with respect to the photoelectric conversion unit.   
     
     
         17 . The imaging element according to  claim 15 , wherein
 the P-type region is formed in the opening portion.   
     
     
         18 . The imaging element according to  claim 15 , wherein
 a through trench is also formed in the opening portion.   
     
     
         19 . The imaging element according to  claim 15 , wherein
 the P-type region formed in the opening portion is formed larger than the P-type region formed in a portion other than the opening portion.   
     
     
         20 . The imaging element according to  claim 15 , wherein
 a contact region for fixing a potential is formed in at least one pixel of a plurality of pixels that is electrically conductive by the opening portion.