Longitudinal dark-conductance measurements were performed on vacuum-evaporated (111)-type thin (0.0003 to 0.0007mm) films. Effective activation energies which ranged from 0.44 to 0.50eV were deduced from the data. The conductance which was exhibited by the film could be separated into a bulk component and a surface component; with associated activation energies of 0.44 and 0.45eV, respectively. The addition of cationic dyes gave rise to an increase in the film conductance which was accompanied by a significant decrease in the activation energy. Anionic dyes caused a marked decrease in the conductance, without any corresponding increase in the activation energy.

J.Feldott: Crystal Lattice Defects and Amorphous Materials, 1987, 15[1-4], 345-9