COTS CMOS active pixel sensors damage after alpha, thermal neutron, and gamma irradiation

BESSIA, F. A., PEREZ, M., SIDELNIK, I., HARO, M. S., BLOSTEIN, J. J., BERISSO, M. G., ... & LIPOVETZKY, J.

Neuquén

Conferencia; http://ieeexplore.ieee.org/document/7574085/; 2010

UNCo, IEEE CASS

This work compares the damage produced by alphaparticles, thermal neutrons and gamma photons to Commercial-Off-The-Shelf CMOS image sensors. Image sensors were exposedto alpha particles from the decay of Uranium and Americiumsources which caused permanent damage to pixels immediatelyafter a particle hit. Similar failure mode was seen when sensorswere exposed to thermal neutrons in the Neutron Imaging Facilityof the RA-6 Nuclear research reactor, whereas no damage wasseen after exposure to 137 Cs gamma rays. Due to the similaritybetween alpha and thermal neutron effects, and since silicontransmutation by neutron capture is very unlikely, we concludethat the Boron-Phosphorous Silicate Glass (BPSG) on top of thesilicon acts as a conversion layer producing charged particleswhich in turn cause damage to the sensor.