Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10707357 | Journal of Crystal Growth | 2011 | 4 Pages |
Abstract
The nucleation and growth of GaAs nanowires fabricated by molecular beam epitaxy (MBE) following the Au-assisted vapor-liquid-solid mechanism were compared on GaAs(1Â 1Â 1)B and on Si(1Â 1Â 1) substrates. On both substrates, reflection high-energy electron diffraction (RHEED) patterns and scanning electron microscopy (SEM) images of several samples belonging to a growth time series were analyzed. During the nucleation stage, growth on Si(1Â 1Â 1) is dominated by horizontally growing traces and coalescing islands, while growth on GaAs(1Â 1Â 1)B proceeds instantly in the vertical direction. After this nucleation stage, the Si substrate is covered by a closed, rough GaAs layer, and nanowires of similar shape grow on both substrates with similar axial and radial growth rates. However, the diameter of the nanowires on Si(1Â 1Â 1) is different than that on GaAs(1Â 1Â 1)B, because the size of the Au droplets, which result from the annealing of a thin Au layer, is different on the two types of substrates.
Keywords
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Condensed Matter Physics
Authors
Steffen Breuer, Maria Hilse, Lutz Geelhaar, Henning Riechert,