Measurement of charge transfer potential barrier in pinned photodiode CMOS image sensors  

作　　者：曹琛 张冰 王俊峰 吴龙胜 

机构地区：[1]Xi'an Microelectronics Technology Institute [2]Xi’anMicroelectronicsTechnologyInstitute

出　　处：《Journal of Semiconductors》2016年第5期56-60,共5页半导体学报（英文版）

基　　金：Project supported by the National Defense Pre-Research Foundation of China(No.51311050301095)

摘　　要：The charge transfer potential barrier （CTPB） formed beneath the transfer gate causes a noticeable image lag issue in pinned photodiode （PPD） CMOS image sensors （CIS）, and is difficult to measure straightforwardly since it is embedded inside the device. From an understanding of the CTPB formation mechanism, we report on an alternative method to feasibly measure the CTPB height by performing a linear extrapolation coupled with a horizontal left-shift on the sensor photoresponse curve under the steady-state illumination. The theoretical study was pertbrmed in detail on the principle of the proposed method. Application of the measurements oil a prototype PPD-CIS chip with an array of 160 ×160 pixels is demonstrated. Such a method intends to shine new light oil the guidance for the lag-free and high-speed sensors optimization based on PPD devices.The charge transfer potential barrier （CTPB） formed beneath the transfer gate causes a noticeable image lag issue in pinned photodiode （PPD） CMOS image sensors （CIS）, and is difficult to measure straightforwardly since it is embedded inside the device. From an understanding of the CTPB formation mechanism, we report on an alternative method to feasibly measure the CTPB height by performing a linear extrapolation coupled with a horizontal left-shift on the sensor photoresponse curve under the steady-state illumination. The theoretical study was pertbrmed in detail on the principle of the proposed method. Application of the measurements oil a prototype PPD-CIS chip with an array of 160 ×160 pixels is demonstrated. Such a method intends to shine new light oil the guidance for the lag-free and high-speed sensors optimization based on PPD devices.

关 键 词：CMOS image sensors （C1S） pinned photodiode （PPD） charge transfer potential barrier （CTPB） photoresponse curve 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TN364.2[自动化与计算机技术—控制科学与工程]