Bachelor Defence: Anders Valdemar Bjørlig

”Ag Catalysed InAs Nanowire Growth and Scanning Electron Microscopy”

Abstract
This project studies the possibilities of Ag as catalyst for growth of InAs
Nanowires. Two experiments are done. One investigating the development
of a 10 nm Ag _lm during annealing at varying time scales and the other
exploring epitaxial growth of InAs Nanowires on (001) and (111)B substrates
with a 2 nm Ag _lm where the growth temperature is varied. Characterization
is done in a scanning electron microscope. The Ag _lm was deposited by
electron beam evaporation and the growth was conducted inside a molecular
beam epitaxy system. It is discovered that Ag particles appear already at
room temperature and that the mean particle area increases with annealing
time. Nanowire growth was present at 420_C growth temperature, but it was
not possible to prove that the Ag had catalysed it. Surface structure at this
temperature was made of triangular islands for the (111)B substrate and
square holes for the (001). The former is similar to results from a study done
with Au on GaAs (111)B where Nanowire growth was achieved indicating
that this is the preferable growth temperature for future experimentation.