GROWTH OF GAYIN1-YAS-INP HETEROSTRUCTURES BY MOLECULAR-BEAM EPITAXY

Lattice-matched layers of GayIn1-yAs (y = 0.47) have been grown at 510°C on (100) InP substrates by molecular beam epitaxy. Epitaxial layers of highly uniform composition were achieved by mixing Ga and In together in a single source, Reproducible flux control was achieved by careful use of a quadrupole mass analyzer. In addition, the morphology, reflection electron diffraction, and electrical properties of GayIn1-yAs epitaxial layers were studied as function of y. When y ≃ 0.47 the epitaxial layers exhibit mirrorsmooth, featureless morphology devoid of misfit dislocation-induced crosshatching. Such crosshatching becomes prominent when y = 0.41 and y = 0.50. Further, those epitaxial layers which are under tensile stress (y > 0.47) tend to exhibit cracking when thermally cycled. The best unintentionally doped epitaxial layers had Nd − Na ≃ 2 × 1017 cm-3 and μ77 = 6500 cm2/Vsec. InP/Ga0.47In0.53As/InP double heterostructures have also been fabricated and made to lase at 77°K under optical excitation conditions. These lasers have a threshold of 6.2 kW/cm2 and an output wavelength of about 1.425 μm. © 1978, The Electrochemical Society, Inc. All rights reserved.