METHOD FOR MANUFACTURING CMOS IMAGE SENSOR

摘要

A method for manufacturing a CMOS image sensor is provided to improve low illumination characteristics by minimizing the formation of electron-hole pairs due to crystal defects existing on a photodiode. A semiconductor substrate(100) having an isolation region and an active region is prepared. A plurality of gate polys(120) are formed on the active region. A photodiode(140) with a predetermined depth is formed in the resultant structure by implanting N type ions into the substrate through one side portion of the gate poly. A nitride layer is formed on the entire surface of the resultant structure. A spacer is formed at sidewalls of the photodiode region and gate polys by etching selectively the nitride layer using a spacer mask capable of blocking the photodiode region alone. A P type ion doped region is formed by implanting P type ions to a surface of the photodiode region using a mask capable of blocking the other regions except the photodiode region. The spacer is removed from the photodiode region.