Identification of Radiation Induced Dark Current Sources in Pinned Photodiode CMOS Image Sensors

Author

Goiffon, V. ; Virmontois, C. ; Magnan, P. ; Cervantes, P. ; Place, S. ; Gaillardin, M. ; Girard, S. ; Paillet, P. ; Estribeau, M. ; Martin-Gonthier, P.

Author_Institution

Université de Toulouse, ISAE, Toulouse, France

Volume

59

Issue

4

fYear

2012

Firstpage

918

Lastpage

926

Abstract

This paper presents an investigation of Total Ionizing Dose (TID) induced dark current sources in Pinned PhotoDiodes (PPD) CMOS Image Sensors based on pixel design variations. The influence of several layout parameters is studied. Only one parameter is changed at a time enabling the direct evaluation of its contribution to the observed device degradation. By this approach, the origin of radiation induced dark current in PPD is localized on the pixel layout. The PPD peripheral shallow trench isolation does not seem to play a role in the degradation. The PPD area and a transfer gate contribution independent of the pixel dimensions appear to be the main sources of the TID induced dark current increase. This study also demonstrates that applying a negative voltage on the transfer gate during integration strongly reduces the radiation induced dark current.

Keywords

Current measurement; Dark current; Ionizing radiation; Layout; Logic gates; Photodiodes; Radiation effects; Active pixel sensors (APS); CMOS image sensors (CIS); RHBD; charge transfer; dark current; deep submicron process (DSM); image sensors; ionizing radiation; leakage current; monolithic active pixel sensors (MAPS); pinned photodiodes (PPD); radiation hardening; shallow trench isolation (STI); total ionizing dose (TID); transfer gate;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/TNS.2012.2190422

Filename

6186799