Electrical conductivity and thermo-electric power of a-Se80xInx and Se80xGe₂₀Inx thin films

The dc conductivity and thermo-electric power of a-Se 80–x In x (x = 5, 10, 15, 20, 30) and a-Se 80–x Ge 20 In x (x = 0, 5, 10, 15, 20) thin films are reported in the present work. The free-charge-carrier concentration is calculated with the help of dc conductivity and thermo-electric power measurements. The calculated values of the free-charge-carrier concentration have been used to evaluate the free-charge-carrier mobility from which the grain boundary potential was evaluated. The results are interpreted in terms of band tailing and the structure of Se–In, Se–Ge–In, and the grain boundary potential barrier. PACS Nos.: 73.61-p, 61.43Dq