RAMAN-STUDY OF OXYGEN-DEFICIENT YVO4 SINGLE-CRYSTALS

Oxygen deficiency which is an inherent problem in melt grown YVO4 sing le crystals was investigated by Micro-Probe Raman Spectroscopy (MPRS). External vibrational modes at 157cm(-1), 162cm(-1) and selected inter nal vibrational modes at 379cm(-1), 840cm(-1) of full Raman spectra we re compared with different YVO4 crystals grown by the Czochralski (CZ) technique both with and without annealing in an O-2 atmosphere as wel l as by top seeded solution growth technique (TSSG) in directly produc ed oxygen deficiency-flee form. Special differences of above mentioned frequencies and over 1000cm(-1) were observed in the Raman spectra, w hich could prove that the growth technologies generated different rate s of oxygen deficiency in addition to critical intrinsic segregation e ffects in YVO4 which significantly determine the crystal quality.