Structural and Optoelectronic Properties of Nanocrystalline CdTe Thin Films Synthesized by Using SILAR Technique

Abstract

Nanocrystalline CdTe thin films were deposited on amorphous glass substrate using successive ionic layer adsorption and reaction (SILAR) technique. The films are characterized using XRD, FESEM, optical absorption techniques and electrical resistivity measurement. The XRD pattern revealed that nanocrystalline CdTe thin films has mixed phase of hexagonal and cubic crystal structure. The calculated crystallite size from the XRD measurement was found to be in the range of 9-12 nm. FESEM image showed uniform deposition of the material over entire glass substrate and film consists of interconnected spherical grains of nanometer size. Compositional analysis showed that the nanocrystalline CdTe thin film becomes cadmium deficient and tellurium richer. The optical absorption studies show that the films have a direct band gap of 1.51 eV. The room temperature resistivity of the synthesized nanocrystalline CdTe films measured by two probe method was found to 6.64 × 10 4 Ω.cm.

Influence of growth time on the properties of CdTe thin films grown by electrodeposition using acetate precursor for solar energy application

“…The structure, morphology, surface roughness, and optical properties of CdTe thin films depend on the growth method and optimization of growth parameters [5]. There are several methods to grow CdTe thin films, such as vacuum evaporation [12], chemical molecular beam deposition (CMBD) method [13], close space sublimation (CSS) [14], physical vapour deposition [15], successive ionic layer adsorption and reaction (SILAR) [16], pulsed laser deposition (PLD) [17], metal-organic chemical vapour deposition (MOCVD) [18], coprecipitation [19], Radio frequency (RF) sputtering [20], sol-gel [21], chemical bath deposition (CBD) [22] and electrodeposition (ED) [23]. Each growth technique has its advantages and disadvantages.…”