Processing and Characterization of Tin Chalcogenide Thin Films by Thermal Evaporation
International Journal of Current Research and Review
Due to the limitations of currently used materials like indirect band gap Si and Ge, binary and ternary compounds of high melting point, toxicity and scarcity of elements, there is a significant demand for alternate compound semiconductors towards energy harnessing applications. Tin selenide (SnSe), being a member of the IV-VI chalcogenide family, has gained wide attention due to its favorable physical properties such as direct band gap, high absorption coefficient and optimum melting
... m melting temperature. Thin film deposition is intrinsically significant, because it offers a low temperature versatile process comprising low material consumption and provides large area module bearing tunable material properties compared to bulk counterparts. Therefore, special emphasis has been paid to prepare two dimensional SnSe thin film structures. In this regard, high pure (99.999%) Sn and Se elements were weighed in stoichiometric proportions and sealed in specially cleaned quartz ampoules. The ampoule containing the materials was heated in a muffle furnace and periodically rotated using a DC motor of 60 rpm, in order to forge the uniform SnSe precursor. Amorphous thin films have been deposited on glass substrates by thermal evaporation under high vacuum in room temperature using the stoichiometric SnSe charge. Optical microscopy (OM) and scanning electron microscopy (SEM) tools were employed to investigate the surface morphology of the prepared thin films. Systematic energy dispersive analysis by X-rays (EDAX) revealed the homogeneity and even distribution of Sn and Se in the samples. X-ray diffraction (XRD) studies were carried out to probe the atomic structure and quality. The grains were found distributed uniformly, without pinholes and the particle size has been enhanced upon controlled thermodynamic conditions.