WELL-TO-SUBSTRATE PHOTODIODE FOR USE IN CMOS SENSOR BASED ON SALICIDE PROCESS

摘要

PPROBLEM TO BE SOLVED: To manufacture an image sensor by utilizing a modern salicided (CMOS) process in a preferred embodiment, in relation to an image sensor having a well (203)-to-substrate (200) diode as a photodetector. PSOLUTION: A field oxide film region (207) above a diode junction is transparent to visible light, thus allowing a photodiode to have competitive quantum efficiency as compared to devices having source/drain diffusion-to-substrate photodiodes fabricated based on a non-salicided process. The photodiode can be integrated as part of a sensor array with digital circuitry using a relatively unmodified digital CMOS fabricating process. Furthermore, the well-to-substrate structure allows the optical properties of the photodiode to be designed by modifying the well without deleterious effects, to approximately a first order, on the characteristics of a FET built in another similar well. PCOPYRIGHT: (C)2010,JPO&INPIT