Electrical and photovoltaic properties of indium-tin-oxide/<i>p</i>-InSe/Au solar cells

Abstract

Conditions for efficiency improvement and optimization in indium-tin-oxide/p-indium-selenide solar cells are discussed in this paper. This aim is achieved by using low-resistivity p-indium-selenide and by incorporating a back-surface-field contact. This contact is insured by a p-indium selenide/gold barrier whose rectifying behavior is explained through the complex impurity structure of p-indium-selenide. Electrical and photovoltaic properties of the cells are also reported. The efficiency parameters under AM1 simulated conditions have been improved up to 32 mA/cm2 for the short-circuit current density, 0.58 V for the open-circuit voltage, and 0.63 for the filling factor. As a result, solar efficiencies larger than 10% in annealed cells and 8% in unannealed ones have been attained. The limitations of these devices are discussed by investigating the dependence of electrical and efficiency parameters in function of photon flux and temperature.