Two-dimensional pixel image lag simulation and optimization in a 4-T CMOS image sensor  

作　　者：于俊庭 李斌桥 于平平 徐江涛 牟村 

机构地区：[1]School of Electronics Information Engineering,Tianjin University [2]Logistics Management Office,Hebei University of Technology

出　　处：《Journal of Semiconductors》2010年第9期59-63,共5页半导体学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.60806010,60976030);the Tianjin Innovation Special Funds for science and Technology,China(No.05FZZDGX00200)

摘　　要：Pixel image lag in a 4-T CMOS image sensor is analyzed and simulated in a two-dimensional model.Strategies of reducing image lag are discussed from transfer gate channel threshold voltage doping adjustment,PPD N-type doping dose/implant tilt adjustment and transfer gate operation voltage adjustment for signal electron transfer.With the computer analysis tool ISE-TCAD,simulation results show that minimum image lag can be obtained at a pinned photodiode n-type doping dose of 7.0×10^12 cm^-2,an implant tilt of -2°,a transfer gate channel doping dose of 3.0×10^12 cm^-2 and an operation voltage of 3.4 V.The conclusions of this theoretical analysis can be a guideline for pixel design to improve the performance of 4-T CMOS image sensors.Pixel image lag in a 4-T CMOS image sensor is analyzed and simulated in a two-dimensional model.Strategies of reducing image lag are discussed from transfer gate channel threshold voltage doping adjustment,PPD N-type doping dose/implant tilt adjustment and transfer gate operation voltage adjustment for signal electron transfer.With the computer analysis tool ISE-TCAD,simulation results show that minimum image lag can be obtained at a pinned photodiode n-type doping dose of 7.0×10^12 cm^-2,an implant tilt of -2°,a transfer gate channel doping dose of 3.0×10^12 cm^-2 and an operation voltage of 3.4 V.The conclusions of this theoretical analysis can be a guideline for pixel design to improve the performance of 4-T CMOS image sensors.

关 键 词：image lag two-dimensional simulation doping dose implant tilt CMOS image sensor 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TP391.9[自动化与计算机技术—控制科学与工程]