Higher mobility of charge carriers in InAs/GaAs superlattices through the elimination of InGaAs alloy disorders on GaAs

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InP films have been deposited on amorphous sapphire substrate by means of the metallorganic chemical vapour deposition technique with and without PH3/H-2 plasma preactivation. Polycrystalline materials, having average grain sizes of about 40 nm, which, however, vary according to the growth parameters, were obtained. The structural and compositional disorder strongly influence the optical and electrical properties. The most structurally disordered films present the largest photoluminescence (PL) efficiency a

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Growth temperatures between 450 and 520 degrees C and V/III ratios of 2-8 were explored to optimize the crystalline quality and the transport properties of compressively strained InxGa1-xAs/InP heterostructures (0.53 < x < 1). 77 K Hall mobilities as high as 118000 cm(2) V-1 s(-1) with n(s) = 1.4 x 10(12) cm(-2) were measured on structures incorporating an In0.8Ga0.2As channel grown with optimized conditions.

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Modulation doped GaAs/In0·25Ga0·75As/Al0·3Ga0·7As high electron mobility transistor structures were grown using different molecular beam epitaxy growth temperatures and In0·25Ga0·75 As channel thicknesses. Drain current deep level transient spectroscopy (DLTS) and standard capacitance DLTS measurements were carried out on these devices using a Fourier transform technique. The results show that traps in the barrier as well as those in the buffer have an influence on the drain current of such transistors. In

Quantum wire heterostructures, such as V- and T-shaped wires, are very promising candidates for low-threshold lasing. A crucial issue is the excitonic vs. free-carrier nature of the radiative recombination. Here, we report on magnetophotoluminescence studies of GaAs and InGaAs V-shaped wires that allow to discriminate different regimes of radiative recombination.

Higher mobility of charge carriers in InAs/GaAs superlattices through the elimination of InGaAs alloy disorders on GaAs

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