Patent ID: 6982187

Claim:
A method for making shallow trench type pixel for complimentary metal oxide semiconductor (CMOS) image sensor, comprising: forming a CMOS image sensor on an epitaxial wafer having a structure including an epitaxial layer doped with a low dopant concentration positioned on a p-type or n-type substrate doped with a high concentration; forming a first photoresist layer over said structure, patterning the first photoresist layer, and etching the epitaxial layer so as to form a shallow trench on a pixel area defined by trench isolation structures; removing said first photoresist layer; forming a second photoresist pattern coexistive with said trench isolation structures so as to form a photodiode junction in at least a portion of the shallow trench of the pixel area, and, then, conducting ion-implanting process; and removing said second photoresist pattern and conducting a thermal treatment process.