Study of the InP-InSb Quasi-binary Phase Diagram

An InP-InSb quasi-binary phase diagram was determined by differential thermal analysis, EPMA and microscopic observation. The eutectic temperature was found to be 525±3.7°C. By using the EPMA. The compositions of solids in equilibrium with liquid at 690 and 565°C are determined to be 98.5 and 98.2 mol% InP, respectively. The calculated quasi-binary phase diagram was found to agree well with the experimental data. In the thermodynamic calculation, the compositions of the eutectic point and the solubility limit of InSb in InP at the eutectic temperature were shown to be 0.02 mol% InP and 1.85 mol% InSb, respectively. It became clear that the liquid and solid phase interaction energy parameters are represented as Ωl=25000−18T and ΩS=6634 cal/mol, respectively.