Method and fabricating complementary metal-oxide semiconductor image sensor with reduced etch damage

摘要

The present invention relates to a method for fabricating a complementary metal-oxide semiconductor (CMOS) image sensor. Prior to forming an N-type ion implantation region and a first and a second P⁰-type ion implantation regions, an oxide layer and a nitride layer are sequentially formed on a substrate and are subsequently patterned to form a protective pattern structure with a specific arrangement with respect to a photodiode and a gate structure of a transfer transistor. Afterwards, the gate structure is formed on the substrate. In the existence of the protective pattern structure, an N-type ion implantation process for forming the N-type ion implantation region for use in the photodiode, a first P⁰-type ion implantation process for forming the first P⁰-type ion implantation region and a spacer formation process are consecutively performed. A second P⁰-type ion implantation process for forming the second P0-type ion implantation region is performed thereafter.