Among the inanimate objects, crystals have attracted man from timeimmemorial. The enchanting colors, the smooth surface with scintillatingreflections of light, the definite and varied shapes with sharp edges, the deeptransparency of some perfect crystals, all together aroused the aesthetic senseof early man who used them as ornaments. The utility of crystals has extendedfrom the bounds of ornaments to several useful applications in optical,electrical and opto-electronic devices.Today, crystals are the pillars of modern technology. The stronginfluence of single crystal in the present day technology is evident from therecent advancement in the field of semiconductors, polarizers, transducers,infrared detectors, ultrasonic amplifiers, ferrites, magnetic garnets, solid statelasers, nonlinear optic, piezoelectric, acousto-optic, photosensitive materialsand crystalline thin films for microelectronics and computer industries. Allthese developments were achieved because of the availability of single crystalslike silicon, germanium, gallium arsenide and invention of nonlinear opticalproperties in some inorganic, semi-organic and organic crystals. Researchersworldwide have always been in the search of new materials and their singlecrystal growth.The solid-state material can be classified into single crystals,polycrystalline and amorphous materials depending upon the arrangement ofconstituent molecules, atoms or ions. An ideal crystal is one, in which thesurroundings of each atom would be exactly the same as the surrounding ofevery other similar atom. Real crystals are finite and contain defects. However,2single crystals are solids in the most uniform condition that can be attained andthis is the basis for most of the uses of crystals.The uniformity in single crystals transmits electro magnetic waveswithout scattering. Hence, the process of producing single crystals, which offerhomogeneous media in the atomic level with directional properties, attractsimmense attention than any other process. The methods of growing crystals arevery wide and mainly dictated by the characteristics of the material and its size(Buckley, 1951; Mullin, 1976).

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