Formation of self-assembled large droplet-epitaxial GaAs islands for the application to reduced reflection

Abstract

The structural and reflectance properties of large gallium (Ga) droplets and GaAs islands grown by droplet epitaxy (DE) were presented. The reflectance results of self-assembled large GaAs islands by DE suggest the possibility of a novel method for antireflective coating. The diameter, height, density, and aspect ratio of large Ga droplets were investigated up to the scale of optical size. After GaAs island growth, the reflectance of s-polarization at 70 degrees on in-situ measurement was reduced up to approximately 2%-20% in the wavelength range of 350-900 nm. For large GaAs islands, reduction of reflectance for s-, p-polarization at 20 degrees-80 degrees and reduction of reflectance at normal incidence was presented. This result shows that a layer of self-assembled large GaAs islands by DE can be a good candidate for an antireflector for high-quality optoelectronic devices. (C) 2013 AIP Publishing LLC