Synthesis of CuInSe 2 films by rapid thermal processing of stacked elemental layers

Abstract

CuInSe 2 (CIS) films were prepared by the stacked elemental layer (SEL) technique with subsequent post deposition rapid thermal processing. This technique offered uniform deposition over a considerably large area (∼4 cm 2) with perfect control on the individual elemental fluxes. In this method, elemental layers of Cu, In and Se were sequentially deposited on soda-lime glass substrates at room temperature (300 K) in appropriate thickness ratios to ensure the desired composition in the film. The layers were annealed by the rapid thermal process in a temperature range of 373–723 K with an interval of 100 K and at a high ramp rate (∼30 K s −1) using tungsten lamps to ascertain the optimum annealing condition. Structural investigations were carried out by the XRD measurements in order to optimize the annealing parameters (e.g., ramp rate and annealing temperature) for obtaining high quality CIS films free from the deleterious secondary binary phases. It was found that high quality films could be obtained by annealing the stack at 673 K for 3 min in argon atmosphere.