Growth and characterization of lattice-matched epitaxial films of GaxIn1−xAs/InP by liquid-phase epitaxy

We determined the conditions for successful lattice-matched growth by liquid-phase epitaxy near T = 620‡ C of GaXIn1−XAs on [111B] InP substrates. We have used the results of the growth of both lattice-matched and intentionally lattice-mismatched epitaxial layers, (0.4 ≤ X ≤ 0.7) to calculate a phase diagram which gives the correct liquidus temperature, (TL ± 1‡ C), and the correct solid composition, (± 5 % of the nominal composition), for the entire range of growth solutions considered for this important ternary semi-conductor system. The parameters appropriate to this calculation are significantly different from those used to describe the growth of GaXIn1−XAs on GaAs. The results of this calculation play an important part in the better understanding of the quaternary alloy GaXIn1−XAsyP1−y. Our measurements show that the ternary alloy lattice-matched to InP is Ga0.47In0.53As, semiconductor with a direct band gap about 0.75 eV at room temperature. We have grown p-n junction homostructures and double-heterostructures on InP substrates. These wafers have been used to make detectors in the 1.0 – 1.7/um range of the optical spectrum.