Characteristics of the boron doped CdSe films deposited by spray pyrolysis method

In this study, Boron doped CdSe films were deposited by spray pyrolysis under different deposition conditions. The influence of the preparation technique on the structural, morphological and optical properties of the Boron doped CdSe films were investigated by using X-ray diffraction (XRD), SEM analysis and optical transmission. The optical properties of the films were investigated from optical absorption coefficient and transmittance spectra data using double beam visible spectrophotometer. Boron doped CdSe films were prepared by spray pyrolysis technique at 2750C substrate temperature, which is using boric acid (H3BO3) as dopant source, and their properties were investigated as a function of doping concentration. Boron doping was achieved by adding 0.0025 M, 0.010 M, 0.015 M, 0.05 M. H3BO3 to the starting solution. The crystal structure of the films was studied by X-ray diffraction with Cu-K radiation (1.5406 oA). The range of 2 angle was from 20o to 80o. X-ray analysis showed that the films were polycrystalline fitting well with a cubic structure and have preferred orientation in the diffraction lines produced by the (100), (002), (101), (200)CdO, (103), (202), (210) and (300) planes of hexagonal (wurtzite) structure of CdSe, respectively. Optical band gap of the undoped and B-doped CdSe films were found to vary from 1.74 to 2.17 eV. The changes observed in the energy band gap and structural properties of the films related to the boric acid concentration are discussed in detail.