Synthesis of CdO:SnO2 alloyed thin films for solar energy conversion and optoelectronic applications

Abstract

CdO:SnO2, alloyed thin films were successfully deposited on glass substrates under the deposition condition of 60 °C of NaOH solution, using two solution based methods: successive ionic layer adsorption and reaction and solution growth technique. The crystallographic studies were done using X-ray diffractometer and scanning electron microscope. The deposited alloyed samples were annealed between 100 and 250 °C using Master Chef Annealing Machine. Rutherford backscattering Spectroscopy analysis confirmed the percentage of the elements of cadmium, tin, and oxygen in the alloyed thin films. The optical characterization was carried out using UV-1800 double beam spectrophotometer. The alloyed thin films of samples A14 and A16 of CdO:SnO2 show optical transmittance of 16–60% in the ultraviolet region, 61–59% in the visible, and 59–58% in the near-infrared regions of electromagnetic spectrum for sample A14 annealed at 100 °C. Sample A16 annealed at 150 °C has an optical transmittance of 27–70% in the ultraviolet region, 70–84% in the visible and 85–87% in the near infrared regions of electromagnetic spectrum. The two samples, have equal direct wide band gap of 3.70 ± 0.05 eV. From the spectral qualities, these compound alloyed thin films may be found useful in heat mirror applications, active layer in various types of solar cells and passive layer in heat and cold mirror application, galvanizing materials. It can also found interesting as semiconductor materials for electronic applications.