Investigation of Bulk Electron Traps Created by Fast Neutron Irradiation in a Buried N-Channel CCD

Electron traps created by high energy (~15 MeV) neutron irradiation at 300°K have been characterized by the double pulse technique in an n-buried-channel CCD. Measurements have been made of electron emission from the traps as a function of time from 77°K to 300°K. Three distinct trap levels are observed at (Ec-Et) equals 0.14, 0.23, and 0.41 eV. Electron emission from the traps as a function of time does not follow the expected exponential time behavior. Analysis of the dispersion in the time vs. emission curves leads to apparent widths of 0.08 and 0.10 eV of the energy levels at Ec - 0.14 and Ec - 0.41 eV, respectively. Introduction rates of the levels and possible physical defects which create the levels are also discussed.