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

Vincent Goiffon (1) , Cédric Virmontois (1) , P. Magnan (1) , P. Cervantes (1) , Sébastien Place , M. Gaillardin (2) , Sylvain Girard (2) , Philippe Paillet (2) , Magali Estribeau (1) , P. Martin-Gonthier (1)

1 ISAE-SUPAERO - Institut Supérieur de l'Aéronautique et de l'Espace
2 DAM/DIF - DAM Île-de-France

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.

Domaines: Sciences de l'ingénieur [physics]

Vincent Goiffon, Cédric Virmontois, P. Magnan, P. Cervantes, Sébastien Place, et al.. Identification of Radiation Induced Dark Current Sources in Pinned Photodiode CMOS Image Sensors. IEEE Transactions on Nuclear Science, 2012, 59 (4), pp.918 - 926. ⟨10.1109/TNS.2012.2190422⟩. ⟨ujm-01011681⟩