Tunability and Graded Energy Band Gap of Chemical Bath Deposited Cadmium Sulfide (CdS) Thin Film for Optoelectronic Applications
CdS thin films have continued to receive scientific and technological attention due to their potential applications in efficient solar energy conversion and utilization in device fabrication. In this research, CdS thin films were deposited on indium doped tin oxide (ITO) substrates of dimension 2.3 by 2.4 cm2. Three different aqueous bath solutions of CdS were formed by increasing the concentration of cadmium acetate as a source of cadmium while the concentration of ammonium chloride and thiourea as a source of sulfur remained constant in the reaction bath as against the usual convention to ascertain the strength of the constituents in the reaction. The energy band gap of the films decreases with increase in the concentration of cadmium as a constituent of the bath while the films optical transmittance was found to increase with increase in concentration. This indicates that the energy band gap of the films can be predetermined by the choice of the constituent of the concentration in the chemical bath deposition technique (CBD). The increase in the transmittance for both as deposited and annealed CdS confirms the suitability of the films as window layer device, solar cell and optoelectronic applications.
Sunday Samuel Oluyamo,
Abass Akande Faremi,
Tunability and Graded Energy Band Gap of Chemical Bath Deposited Cadmium Sulfide (CdS) Thin Film for Optoelectronic Applications, Nanoscience and Nanometrology.
Vol. 6, No. 1,
2020, pp. 5-9.
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