Novel N Profile in Si-Ox Interface for CMOS Image Sensor Performance Improvement

摘要

A semiconductor device including first and second isolation regions supported by a substrate, a first array well supported by the first isolation region, the first array well having a first field implant layer embedded therein, the first field implant layer surrounding a first shallow trench isolation region, a second array well supported by the second isolation region, the second array well supporting a doped region and a drain and having a second field implant layer embedded therein, the second field implant layer surrounding a second shallow trench isolation region, a stack of photodiodes disposed in the substrate between the first and second isolation regions, and a gate oxide formed over an uppermost photodiode of the stack of the photodiodes, the gate oxide and a silicon of the uppermost photodiode forming an interface, a nitrogen concentration at the interface offset from a peak nitrogen concentration.