Synthesis, growth mechanism and physical properties of vapour-deposited GaTe platelets

The physical vapour deposition (PVD) method has been employed to yield gallium telluride (GaTe) platelets. The morphology and growth mechanism of these platelets were investigated with the aid of scanning electron micrographs. The stoichiometry and homogeneity of the grown samples were confirmed by chemical analysis. The X-ray diffraction (XRD) technique has been used to explore the structure and phase of the compound. On the basis of the Archimedes principle, the density of crystals was estimated to be 5.442 kg mm^-3. The resistivity and conductivity type were determined by the van der Pauw method. UV-vis-NIR studies revealed a direct transition with an energy gap of 1.69 eV. Mechanical properties such as microhardness, toughness, Young's modulus and elastic stiffness constant of GaTe crystals in response to the stress field due to an external load were studied to realize their suitability for radiation detector applications. The present observations provide an insight into the physical properties of the vapour-grown GaTe platelets, which are found to be superior over their melt counterparts.