Method to form a cmos image sensor

Abstract

The present disclosure relates to a method and composition to limit crystalline defects introduced in a semiconductor device during ion implantation. A high-temperature low dosage implant is performed utilizing a tri-layer photoresist which maintains the crystalline structure of the semiconductor device while limiting defect formation within the semiconductor device. The tri-layer photoresist comprises a layer of spin-on carbon deposited onto a substrate, a layer of silicon containing hard-mask formed above the layer of spin-on carbon, and a layer of photoresist formed above the layer of silicon containing hard-mask. A pattern formed in the layer of photoresist is sequentially transferred to the silicon containing hard-mask, then to the spin-on carbon, and defines an area of the substrate to be selectively implanted with ions.