We reveal a novel phenomenon observed after self-catalytic growth of GaAs nanowires (NWs) on Si(111) substrates treated with a Ga focused ion beam (FIB). Depending on the ion dose, NW arrays with various geometrical parameters can be obtained. A minor treatment of the substrate enables a slight increase in the surface density of NWs relative to an unmodified substrate area.
View Article and Find Full Text PDFThis paper presents the results of experimental studies of the effect of Si(111) surface modification by Ga-focused ion beam (FIB) at 30 kV accelerating voltage on the features of the epitaxial GaAs nanowire (NW) growth processes. We experimentally established the regularities of the Ga ions' dose effect during surface modification on the structural characteristics of GaAs NW arrays. Depending on the Ga ion dose value, there is one of three modes on the surface for subsequent GaAs NW growth.
View Article and Find Full Text PDFModern and future nanoelectronic and nanophotonic applications require precise control of the size, shape and density of III-V quantum dots in order to predefine the characteristics of devices based on them. In this paper, we propose a new approach to control the size of nanostructures formed by droplet epitaxy. We reveal that it is possible to reduce the droplet volume independently of the growth temperature and deposition amount by exposing droplets to ultra-low group-V flux.
View Article and Find Full Text PDFSemiconductor quantum dots (QDs) in the InAs/AlGaAs system are of great importance due to their promising optoelectronic and nanophotonic applications. However, control over emission wavelength governed by Al content in the matrix is still limited because of an influence of surface Al content on QD size and density. In this paper, we study the growth of In nanostructures by droplet epitaxy on various AlGaAs surfaces.
View Article and Find Full Text PDFThe paper presents the results of experimental studies of the influence of the local anodic oxidation control parameters on the geometric parameters of oxide nanoscale structures (ONS) and profiled nanoscale structures (PNS) on the surface of epitaxial structures of silicon doped gallium arsenide with an impurity concentration of 5 × 10 cm. X-ray photoelectron spectroscopy measurements showed that GaAs oxide consists of oxide phases GaO and AsO, and the thickness of the GaO layer is 2-3 times greater than the thickness of AsO area-i.e.
View Article and Find Full Text PDFFabrication of AB nanostructures by droplet epitaxy has many advantages over other epitaxial techniques. Although various characteristics of the growth by droplet epitaxy have been thoroughly studied for both lattice-matched and mismatched systems, little is known about physical processes hindering the formation of small size InAs/GaAs nanostructure arrays with low density and thin wetting layer. In this paper, we experimentally demonstrate that the indium droplet diameter can be reduced by decreasing the deposition time, but this reduction is limited by a critical thickness of droplet formation dependent on the substrate temperature.
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