| Abstract: | The growth and structural characteristics of chalcopyrite semiconductor CuInSe2 have been investigated with particular emphasis on the photovoltaic behaviour of the CdS/CuInSe2 thin film heterojunction. It has been found that the structural phase of the CuInSe2 has an important bearing on the photovoltaic behaviour of the heterojunction. Thus the heterojunctions having the sphalerite type cubic CuInSe2 as one of its component have been found to possess better conversion effciency than those employing the chalcopyrite type tetragonal form of CuInSe2. Evidences and argument have been put forward to show that the better efficiency with sphalerite phase arises due to smaller lattice mismatch with CdS base. In addition to the type of structural phase, the state of order of CuInSe2 phase has been found to affect the performance of heterojunctions. The heterojunctions having the disordered sphalerite type CuInSe2 structure exhibits a much lower efficiency than those embodying the ordered CuInSe2 phase. |
