Modeling of Beta Conductivity in Tritiated Amorphous Silicon

Abstract

ABSTRACTThe change with time in the electrical conductivity of a hydrogenated-tritiated amorphous silicon film (a-Si:H:T) has been studied. The conductivity decreased with time after deposition. A model is developed to account for the decrease. The radioactive decay of tritium into helium produces energetic beta particles. Each β particle creates over 1500 electron-hole pairs in the film thereby increasing the conductivity of the film. The 3He atoms diffuse away leaving dangling bonds behind. We find that neutral dangling bonds (D0) are responsible for the decrease in conductivity by acting as recombination centers in the material.