Crystallization in Ga-Sb-Se glasses and influence of the Se content

Crystallization in glasses composed of Ga, Sb and Se has been studied as a function of Se content. Six glass compositions are selected (Ga8Sb27Se65, Ga12Sb23Se65, Ga8Sb32Se60, Ga10Sb30Se60, Ga8Sb37Se55 and Ga8Sb40Se52), with different Se contents. Glass-ceramics are obtained by heating the glass 5 degrees C above its glass transition temperature. Glasses and glass-ceramics are characterized by differential scanning calorimetry, Raman spectroscopy, infrared spectroscopy and X-ray diffraction. A correlation between the Se content, the nature of the phase crystallizing and the electrical conducting properties of the material is evidenced. On one hand, antimony selenide Sb2Se3 crystallizes in over-stoichiometric and stoichiometric glasses compared to the x Ga2Se3 -(100-x) Sb2Se3 line. On the other hand, an unknown phase crystallizes in sub-stoichiometric glasses, followed by Sb2Se3. The resulting glass-ceramics are characterized by a conductivity reaching up to 2 S center dot cm(-1), two order of magnitude higher than other Se-based glass-ceramics.