Growth and dissolution kinetics of III-V heterostructures formed by LPE

When a new layer of a heterostructure begins to form by LPE, conditions of nonequilibrium exist between the existing layer and the new solution. This process has been analyzed for a ternary system in terms of matter transport in both phases and the equilibrium phase diagram. The analysis has been applied to conditions under which the second wave-guiding layer of a double-heterostructure laser may be grown in the (GaAl)As system. It is shown that the active layer tends to dissolve in the subsequent solution. Conditions under which this may be prevented are illustrated. Also illustrated are the forms of the compositional profiles at the heterojunction as a function of growth conditions.