A study of external patterning and internal forces in nanostructure growth
Date of Issue2012
School of Electrical and Electronic Engineering
Uniform and orderly arranged gallium arsenide (GaAs) islands on GaAs(100) substrate are demonstrated by the combination of external patterning in the form of nanosphere lithography and internal forces in the form of catalytic effects and facet formation. The substrate was patterned with an array of 210nm diameter silica nanodisks arranged in a hexagonal fashion with periodicity of 280nm. GaAs islands were found to grow from underneath the silica nanodisks, evolving from disk shape into eventually a pyramidal shape, resulting in the toppling of the supported silica nanodisks. The resulting GaAs islands were observed to follow the size and the arrangement of the silica nanodisks closely. The phenomenon occurred consistently for each nanodisk across a large area of ~50 x 50 μm2. The demonstrated island shape evolution also shows the potential for the growth mechanism to be used to obtain island shape tunability.
DRNTU::Engineering::Electrical and electronic engineering::Antennas, wave guides, microwaves, radar, radio