SOME METHODOLOGIES USED FOR THE SYNTHESIS OF CUPROUS OXIDE: A REVIEW

Cuprous oxide, a semiconductor material has a direct band gap of about 2 eV. Since it is a direct band gap material this imparts higher efficiency especially when used for light emitting diodes (LED). For a long time it was believed that cuprous oxide is a p-type semiconductor but later on n-type cuprous oxide was also prepared. Both these types of cuprous oxides are useful in the fabrication of homo junctions instead of hetero junctions which give rise to higher efficiency of the solar cells. Different researchers have reported different semi-conducting properties of cuprous oxide. Since these properties not only depend upon the nature of the material but also upon the way they are synthesized. The reasons for different properties of the same material are because there may be different number of defects in the same material prepared through different routes. If we compare single crystal silicon to poly crystalline silicon, both have not exactly the same properties. Same is the case in fine and coarse grained materials. It is also noted that depending upon the synthesis conditions; the grain growth will take place at different preferred orientations and hence may result in different conductivity types. Therefore methods adopted for the synthesis of cuprous oxide by various researchers are discussed in this paper.