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OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible.This is an author-deposited version published in : http://oatao.univ-toulouse.fr/
Eprints ID : 14524
To link to this article : DOI :
10.1109/TNS.2014.2360773
URL :http://dx.doi.org/10.1109/TNS.2014.2360773
To cite this version :
Goiffon, Vincent and Estribeau, Magali and
Cervantes, Paola and Molina, Romain and Gaillardin, Marc and
Magnan, Pierre
Influence of Transfer Gate Design and Bias on the
Radiation Hardness of Pinned Photodiode CMOS Image Sensors
.
(2014) IEEE Transactions on Nuclear Science, vol. 61 (6). pp.
3290-3301. ISSN 0018-9499
Any correspondance concerning this service should be sent to the repository administrator: staff-oatao@listes-diff.inp-toulouse.fr
Influence of Transfer Gate Design and Bias on the
Radiation Hardness of Pinned Photodiode
CMOS Image Sensors
Vincent Goiffon1, Magali Estribeau1, Paola Cervantes1, Romain Molina1, Marc Gaillardin2 and Pierre Magnan1
1
Université de Toulouse, ISAE-SUPAERO, 10 avenue E. Belin, F-31055, Toulouse, France
2
CEA, DAM, DIF, F-91297 Arpajon, France
ABSTRACT :
The effects of Cobalt 60 gamma-ray irradiation on Pinned Photodiode (PPD) CMOS Image Sensors (CIS) are investigated by comparing the Total Ionizing Dose (TID) response of several Transfer Gate (TG) and PPD designs manufactured using a 180 nm CIS process. The TID induced variations of Charge Transfer Efficiency (CTE), pinning voltage, Equilibrium Full Well Capacity (EFWC), Full Well Capacity (FWC) and dark current measured on the different pixel designs lead to the conclusion that only three degradation sources are responsible for all the observed radiation effects: the Pre-Metal Dielectric (PMD) positive trapped charge, the TG sidewall spacer positive trapped charge and, with less influence, the TG channel Shallow Trench
Isolation (STI) trapped charge. The different FWC evolutions with TID presented here are in very good agreement with a recently proposed analytical model. This work also demonstrates
that the peripheral STI is not responsible for the observed degradations and thus that the enclosed layout TG design does not improve the radiation hardness of PPD CIS. The results of
this study also lead to the conclusion that the TG OFF voltage bias during irradiation has no influence on the radiation effects. Alternative design and process solutions to improve the radiation hardness of PPD CIS are discussed.
