Calculation of the Al-Ga-In-As phase diagram and LPE growth of Al xGa yIn 1- x-yAs on InP

Abstract

The Al-Ga-In-As phase diagram which is necessary for the growth of Al x Ga y In 1- x-y As layers on InP was calculated by using the simple solution model. The quaternary layers were grown first onto InP(100) substrates from 700°C by the LPE method on the basis of the calculated phase diagram. The surface morphology of the layers was examined in relation to the growth conditions. It was found that pre-heating of the Al and Ga melts was very important for the growth of the quaternary layers. The growth condition of the lattice-matched layer with a 1.12 eV energy gap was obtained. It was difficult to grow thick Al x Ga y In 1- x- y As layers by LPE growth from 700°C due to the very large distribution coefficient of Al.