Composition dependence of viscosity for molten Ga1−xAsx (0.0≤x≤0.53)

Abstract

Viscosity of molten Ga1−xAsx was directly measured by an oscillating cup method. The composition dependence of the synergism viscosity remarkably increases in the vicinity of stoichiometric composition; strong temperature dependence of viscosity was also observed at that composition. Activation energy for viscous flow at the stoichiometric Ga1−xAsx (x=0.5) melt ranges from 250 to 600 meV, which was larger than those of metals such as gallium and indium whose activation energies were about 60–100 meV. We estimate, therefore, that the melt of stoichiometric composition has middle-range ordering like an aggregation whose range is larger than that of short-range ordering in metals such as gallium and indium.