GRAIN-BOUNDARY SCATTERING IN CUINSE2 FILMS

Electrical conductivity and Hall mobility of CuInSe2 films were measured in the temperature range of 77-400 K. The films were deposited with different Cu/In ratios ranging from 0.7-0.9 and at substrate temperatures of 620-720 K. Effects of grain boundary scattering on the electron transport properties were studied carefully and it was observed that scattering at the grain boundaries is a predominant factor controlling the electron transport properties at lower temperatures while complex scattering mechanisms become operative at higher temperatures. The energy values of trap levels and the densities of trap states were also obtained.