CMOS image sensor

Abstract

A pixel of a complementary metal oxide semiconductor (CMOS) image sensor includes a plurality of photodiodes for sensing light to thereby generate photoelectric charges in different regions; a plurality of transfer transistors for transferring photoelectric charges of corresponding photodiodes in response to a first control signal; a floating diffusion region for receiving photoelectric charges transferred by the plurality of transfer transistors; a rest transistor connected between a power supply voltage and the floating diffusion region for resetting the floating diffusion region by controlling a voltage loaded on the floating diffusion region in response to a second control signal; a drive transistor connected between the power supply voltage and the floating diffusion region to serve as a source follower buffer amplifier; and a select transistor connected between the drive transistor and a pixel output terminal for performing an addressing operation in response to a third control signal.

1 . A pixel of a complementary metal oxide semiconductor (CMOS) image sensor, comprising: 
 a plurality of photodiodes for sensing light to thereby generate photoelectric charges in different regions;    a plurality of transfer transistors for transferring photoelectric charges of corresponding photodiodes in response to a first control signal;    a floating diffusion region for receiving photoelectric charges transferred by the plurality of transfer transistors;    a rest transistor connected between a power supply voltage and the floating diffusion region for resetting the floating diffusion region by controlling a voltage loaded on the floating diffusion region in response to a second control signal;    a drive transistor connected between the power supply voltage and the floating diffusion region to serve as a source follower buffer amplifier; and    a select transistor connected between the drive transistor and a pixel output terminal for performing an addressing operation in response to a third control signal.    
     
     
         2 . A pixel layout method of a CMOS image sensor for arranging a pixel recited in  claim 1 , comprising the steps of: 
 arranging an active region for forming a photodiode, diffusion region and body of each transistors as a “T” shape;    forming a plurality of photodiodes separately in active region of head of the “T” shape; and    forming a floating diffusion region, a reset transistor, a drive transistor and a select transistor on the lower active region of the “T” shape.    
     
     
         3 . The pixel layout method as recited in  claim 2 , wherein unit pixels are lay out such that one unit pixel is formed upside down in comparison with a neighboring unit pixel so that the unit pixels engage each other.