Thermodynamic analysis of the MOVPE growth of InxGa1-xN

A chemical equilibrium model is applied to the growth of the InxGa1-xN alloy grown by metalorganic vapor-phase epitaxy (MOVPE). The equilibrium partial pressures and the phase diagram of deposition are calculated for the InxGa1-xN alloy. The vapor-solid distribution relationship is discussed in comparison with the experimental data reported in the literature. It is shown that the solid composition of the InxGa1-xN alloy grown by MOVPE is thermodynamically controlled and that the incorporation of group III elements into the solid phase deviates from a linear function of the input mole ratio of the group III metalorganic sources under the conditions of high mole fraction of decomposed NH3 (high value of alpha), high temperature and low input V/III ratio. The origin of the deviation of the solid composition from the linear relation is also discussed.