Chemical bath deposition and characterization of CdSe thin films for optoelectronic applications

Cadmium selenide (CdSe) thin films of high crystalline quality on glass substrate have been prepared by chemical bath deposition technique from an aqueous bath containing tetramine cadmium and sodium selenosulphate. Structural analysis using XRD shows that the film is single phase, crystallized in hexagonal structure with preferred growth in (111) direction. The energy band gap calculated from the absorption spectra of unannealed CdSe thin films shows an optical band gap of 1.8 eV and absorption coefficient near band edge (α)—0.58 × 10⁵ cm⁻¹. The conductivity of CdSe thin films is n-type.