Temporal changes in the electrical conductivity versus temperature behavior of a tritiated hydrogenated amorphous film were studied. The radioactive decay of T produced β particles (mean energy of 5.7keV) and 3He atoms. The high-energy particles created electron-hole pairs in the film. The 3He atoms diffused away; leaving dangling bonds. At first, the conductivity decreased with time. After some 240h, the conductivity increased. It was proposed that, during the first stage, neutral dangling bonds were responsible for the decrease; by acting as recombination centres. The subsequent increase was attributed to the formation of positively charged dangling bonds. The conductivity data obeyed the Meyer-Neldel rule.

Time Evolution of the Density of States of Tritiated Hydrogenated Amorphous Silicon F.Gaspari, T.Kosteski, S.Zukotynski, N.P.Kherani, W.T.Shmayda: Philosophical Magazine B, 2000, 80[4], 561-9