Nonsilicide source/drain pixel for 0.25-mu m CMOS image sensor

A nonsilicide source/drain pixel is proposed for high performance 0.25-mum CMOS image sensor. By using organic material spin coat and etch back, silic ide is only formed on poly gate which can be used as interconnection, not f or source/drain region that solve the optical opaque and undesirably large junction leakage of silicide, The performance of MOSFET has little change d ue to the high sheet resistance of nonsilicide source/drain. With HP anneal ing and double ion implanted source/drain junction, the dark current can be further reduced. The novel pixel (three transistors, 3.3 mum x 3.3 mum, fi ll factor: 28%) shows low dark current (less than 0.5 fA per pixel at 25 de greesC) and high photoresponse.