Patent ID: 6756618
Filing Date: 2004-06-29
Classification: H01L

Abstract:
A complementary metal-oxide semiconductor (CMOS) image sensor, comprising:a first conductive type semiconductor substrate providing a first photodiode for sensing light having a first wavelength and a second photodiode for sensing light having a second wavelength, shorter than the first wave length, being closely located to the first photodiode, wherein each first and second photodiode includes: a first ion implantation region of a first conductive type formed in a semiconductor substrate of the first conductive type; a second ion implantation region of a second conductive type, contacting to a bottom surface of the first ion implantation region; a third ion implantation region of the second conductive type having a concentration lower than the second ion implantation region, contacting to a bottom surface of the second ion implantation region; and a fourth ion implantation region of the second conductive type having a concentration lower than the second ion implantation region, contacting to a bottom surface of the third ion implantation region; and wherein the second photodiode includes a fifth ion implantation region of a first conductive type, surrounding lateral surfaces of the third and the fourth ion implantation regions and contacting to a bottom surface of the fourth ion implantation region and having a concentration higher than the third and the fourth ion implantation regions.