NATIVE DEFECTS IN III-V-TERNARY ALLOY SEMICONDUCTORS GROWN FROM LIQUID-SOLUTIONS

A thermodynamic model of native defects developed by Van Vechten was extended and applied to III–V ternary alloy semiconductors grown from a liquid solution. Antisites and vacancies were taken to be dominant defects. In order to guarantee the solvability of the mass action equations, the equilibrium of defect-formation reactions and the liquid-solid phase equilibrium were considered with consistency; that is, the same thermodynamic data were used in calculations of the phase diagrams and the defect concentrations. In addition, the effects of the nonideality of the alloy were taken into account in the calculation of the free energies of the reactions. The Al-composition dependence and temperature dependence of the native defect concentrations in Ga1-xAlxAs were calculated as an example. © 1990 The Japan Society of Applied Physics.