Deep-level traps in CCD image sensors

摘要

We have extended by five the number of deep-level traps known to create dark current in charge-coupled device (CCD) image sensors. These include Mn, Pt, and three much weaker traps that are as yet unidentified. Using dark current spectroscopy (DCS) we show that the generation rates at 55 deg range from 6400 electrons/s for Mn to only 2 electrons/s for the weakest trap, which lies 0.27 eV off mid-gap. These weak traps determine the bandwidths and resolution of the trap peaks seen in the dark current spectra.