A CdTe film was deposited on to a soda-lime glass substrate using RF magnetron sputtering. A variable-angle ellipsometer was used to take amplitude and phase change measurements. The refractive index and extinction coefficient was extracted from a multi-oscillator model fit to the ellipsometry data, as a function of wavelength, from 300 to 1500 nm
R. E. Treharne, A. Seymour-Pierce, K. Durose, K. Hutchings, S. Roncallo, D. Lane, Optical design and fabrication of fully sputtered CdTe/CdS solar cells, J. Phys: Conf. Ser.286, 012038, (2011) (Numerical data kindly provided Dr. Robert Treharne)
Cadmium telluride (CdTe) is an inorganic compound that typically crystallizes in a cubic zincblende structure. It is a direct bandgap semiconductor with a bandgap energy of approximately 1.5 eV, making it highly suitable for photovoltaic applications, especially thin-film solar cells. CdTe solar cells are commercially significant due to their lower manufacturing costs and competitive efficiency levels compared to silicon-based cells. Besides photovoltaics, CdTe is also employed in infrared detectors, radiation detectors, and electro-optic modulators. However, the presence of cadmium, a toxic heavy metal, calls for stringent handling and disposal protocols and has prompted research into recycling methods. Synthesis methods for CdTe include physical vapor deposition, chemical vapor deposition, and close-spaced sublimation, among others, each offering unique advantages in terms of film quality and manufacturing scalability. Despite the environmental concerns related to its toxicity, CdTe remains a highly relevant material in renewable energy technologies and continues to attract research efforts aimed at mitigating its environmental impact.