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Crystal growth is the process in which solids in disordered and irregular state culminate around an embryo forming a solid phase nucleus with regular and periodic structure. This phenomenon can be considered as a first order phase transition. Nucleation occurs due to the presence of a surface wall of an ampoule, foreign particles or an impurity component in a three dimensional manner. In order to grow the antimony selenide (Sb 2 Se 3) bulk crystals, the Bridgman-Stockbarger method was employed. Generally, in melt growth methods, two possible types of interfaces occur, namely sharp and diffuse interface. The sharp interface is atomically flat whereas the diffuse interface is atomically rough. The perfection of the grown crystal depends on the type of interface during the liquid-solid transition phase. The critical energy of nucleation and subsequent growth was favored by the free energy of the interface (surface of the nucleus) and the driving force. In the present study, the liquid-solid interface was carefully optimized to obtain atomically smooth interface in order to increase the perfection of the grown crystals. The stoichiometric Sb2Se3 charge was kept in a specially designed quartz ampoule with tapered tip and was placed in the melt growth furnace under 720 °C and the ampoule was translated down at the rate of 4mm/h. The morphological investigations using optical microscopy of the obtained crystal disclosed the absence of imperfections on the surface. The chemical homogeneity of the melt grown Sb2Se3 crystal was assessed by Energy dispersive analysis by X-ray (EDAX) which revealed that the crystals were physically distinct with the right stoichiometric proportions corresponding to orthorhombic phase.

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