Metal 1D micro(nano) self-organized wires on semiconductor surface: Preparation, topology, and optical properties

Abstract

Preparation of selectively deposited wire-like 1D arrays of metal nanoparticles on patterned semiconductor surfaces is reported. A quasi-grating microrelief on the GaAs and InP (100) surfaces has been obtained by anisotropic etching in the mixture HF:H2SO4:H2O2 (2:2:1) and concentrated HCl, respectively. According to the AFM and SEM data, the quasi-periodic microrelief is a set of V-like grooves oriented along the [011] crystallographic direction, with a submicron period and a length over 10 μm. The gold coating has been grown by photostimulated chemical deposition. The surfaces with the quasi-periodic microrelief have been used as site templates for nanoparticle deposition. The EDX data show that gold particles are predominantly located at the microrelief tops and form a system of near-parallel wires. The metal-semiconductor system reflectance and the metal wire-like ensemble transmittance have been numerically simulated in the region of SPP excitation. The generalized effective-medium approximation has been invoked with regard to the gold coating anisotropy which results from the different electron scattering in the wire-parallel and perpendicular directions.