Selective-Area Deposition of Indium and Its Plasmonic Properties

We present an effective process sequence for the deposition
of
indium nanostructures using molecular beam epitaxy (MBE) on a silicon
substrate. Using a template structure composed of inverted pyramids
and V-grooves, we deposit indium nanostructures with various dimensions.
Spatially resolved cathodoluminescence spectroscopy (CL) using an
electron-beam energy of 30 keV electrons shows a localized surface
plasmon (LSP) resonance in spherical particles with a peak wavelength
at 300 nm and a full width at half-maximum of 70 nm for the smallest
particles (diameter of 85 nm), showing high optical quality of the
grown indium. V-groove template structures create indium nanowires
for which CL spectroscopy reveals efficient propagation of surface
plasmon polaritons (SPPs), and angle-resolved CL on the periodic inverted
pyramids reveals optical lattice resonances arising from the array’s
periodicity. The high optical quality of these nanostructures enables
further applications of plasmonic nanostructures in the ultraviolet
(UV) spectral range.