MBE growth optimization of InAs (001) homoepitaxy

Abstract

The optimal conditions for growth of homoepitaxial InAs layers by molecular beam epitaxy were investigated over a wide range of substrate temperatures and As2/In flux ratios at a growth rate of 0.66 monolayer/s. Material quality was investigated using a variety of techniques: differential interference contrast microscopy, scanning electron microscopy, and atomic force microscopy. The results indicated that the InAs layer grown at a temperature between 430 and 450 °C with an As2/In flux ratio of about 15:1 yielded the highest quality, with a defect density of 2 × 104 cm−2 and a root mean square roughness of 0.19 nm. The quality can be further improved by growth at a lower growth rate of 0.22 monolayer/s. The morphology of large oval hillock defects on the InAs layers suggested that these defects originated at the substrate surface.

Molecular beam epitaxy of CuMnAs

“…local formation of multiple incoherent boundaries in close proximity. The overgrowth into a homogeneous layer could be locally further suppressed by the presence of impurities or adatom clustering within the holes [11,12]. The hole elongation is consistent with the presence of a diffusion anisotropy on the polar III-V surface [13], yielding islands that are elongated in the [110] direction of the substrate prior to coalescence.…”

Enhanced Crystal Quality of AlxIn1-xAsySb1-y for Terahertz Quantum Cascade Lasers

“…For each series P As 2 and the T g were kept constant while P Sb 2 was varied. P As 2 was chosen such that high crystal quality InAs can be grown under the same conditions [11]. The results are summarized in Figure 2a.…”

“…The range of T g used in this study was 410 • C to 480 • C. Since Al x In 1-x As y Sb 1-y should be used in heterostructures together with InAs, P As 2 is, in principle, dictated by the optimum BEP to grow high quality InAs [11]. In this study, P As 2 was varied in order to investigate its influence on the composition of Al 0.462 In 0.538 As y Sb 1-y .…”

Non-destructive carrier concentration determination in InAs thin films for THz radiation generating devices using fast differential reflectance spectroscopy

“…Optical spectroscopy experiments utilizing e.g. reflectance (Hinkey et al 2011;Berreman 1966), transmittance (Ye et al 2013) and ellipsometry (Raman et al 2011) measurements should be mentioned here and can be broadly classified as such.…”