Cyclotron resonance measurements were carried out on high quality (In0.52Al0.48As)z(In0.53Ga0.47As)1−z thick layers grown on InP substrates by molecular beam epitaxy. The measurements were performed at 60 K and we were able to obtain the electron effective mass dependence with z in the whole range of composition 0≤z≤1. Using the band-gap values as obtained from photoluminescence measurements on the same samples at 60 K, nonparabolicity corrections were taken into account to obtain the effective mass m0* at the conduction band edge. A nonlinear variation m0* with z could be inferred from our experimental data. The expression m0*(z)/me=0.043+0.042z−0.016z2, which includes a quadratic dependence in z (or a so-called bowing parameter), gives a very good fit to our experimental data.

An investigation of the crystalline and optical properties of AlInAs as a function of the molecular-beam epitaxial growth conditions is reported. The surface reconstruction phases diagram has been established. We show the possibility of growing this material with smooth surface under (Al-In)-stabilized (4×2) reconstructed surface. Such layers present a specific photoluminescence behavior; transmission electron microscopy observations suggest the existence of spinodal decomposition. Films grown under usual (2×4) surface show 2-K photoluminescence peak as narrow as 16 meV (FWHM), but we found that no correlation may be established a priori between the optical and crystalline properties. A high silicon doping study is also reported. We show the segregation and accumulation of Si toward the surface at high level.

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We present a complete investigation of crystalline, optical, and electrical properties of molecular-beam-epitaxial-grown AlGaInAs lattice matched to InP covering the whole range of concentrations. Using the two indium cells method, we show very easy control of lattice matching of this quaternary system which can be written as (Al0.48In0.52As)z(Ga0.47In0.53As)1−z. X-ray double diffraction profiles do not depend on the Al concentration and they show sharp diffraction linewidth. The PL full widths at half maximum are comparable to the narrowest reported. Transmission electron microscopy shows excellent crystallinity for z up to 0.60. Room-temperature electron mobility higher than 4000 cm2/V s for z up to 0.40 is comparable to that of InP and is the best result reported up to now for these quaternary alloys. This system is thus quite suitable for microwave and optical devices applications.

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