Collection efficiency and charge transfer optimization for a 4-T pixel with multi n-type implants  

作　　者：李伟平 徐江涛 徐超 李斌桥 姚素英 

机构地区：[1]School of Electronic and Information Engineering,Tianjin University

出　　处：《Journal of Semiconductors》2011年第12期91-94,共4页半导体学报（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Nos.61036004,60976030)

摘　　要：In order to increase collection efficiency and eliminate image lag, multi n-type implants were introduced into the process of a pinned-photodiode. For the purpose of improving the collection efficiency, multi n-type implants with different implant energies were proposed, which expanded the vertical collection region. To reduce the image lag, a horizontal gradient doping concentration eliminating the potential barrier was also formed by multi n-type implants. The simulation result shows that the collection efficiency can be improved by about 10% in the long wavelength range and the density of the residual charge is reduced from 2.59 × 10^9 to 2.62 × 10^7 cm^-3.In order to increase collection efficiency and eliminate image lag, multi n-type implants were introduced into the process of a pinned-photodiode. For the purpose of improving the collection efficiency, multi n-type implants with different implant energies were proposed, which expanded the vertical collection region. To reduce the image lag, a horizontal gradient doping concentration eliminating the potential barrier was also formed by multi n-type implants. The simulation result shows that the collection efficiency can be improved by about 10% in the long wavelength range and the density of the residual charge is reduced from 2.59 × 10^9 to 2.62 × 10^7 cm^-3.

关 键 词：CMOS image sensor PHOTODIODE collection efficiency charge transfer image lag 

分 类 号：TN364.2[电子电信—物理电子学]