Reduced crosstalk CMOS image sensors

摘要

CMOS image sensor having high sensitivity and low crosstalk, particularly at far-red to infrared wavelengths, and a method for fabricating a CMOS image sensor. A CMOS image sensor has a substrate (202, 302, 602), an epitaxial layer (204, 304, 606) above the substrate (202, 302, 602), and a plurality of pixels (210, 212, 310, 312, 402) extending into the epitaxial layer (204, 304, 606) for receiving light. The image sensor also includes at least one of a horizontal barrier layer (224, 324, 604) between the substrate (202, 302, 602) and the epitaxial layer (204, 304, 606) for preventing carriers generated in the substrate (202, 302, 602) from moving to the epitaxial layer (204, 304, 606), and a plurality of lateral barrier layers (322, 326, 520, 610) between adjacent ones of the plurality of pixels (310, 312, 402) for preventing lateral diffusion of electrons in the epitaxial layer (204, 304, 606).