Abstract
M.Sc. (Physics)
Silicon thin films can be manufactured with the aid of various deposition
techniques, each with its own unique properties. In this study the optical
properties of silicon manufactured with physical vapour deposition from an
electron beam source were studied as a function of layer thickness, deposition
rate and substrate temperature. The index of refraction (n and k) as well as
optical gap eg. were determined with the aid of characterization models derived
specific for optical techniques. These models are covered extensively in the
thesis. It was found that the layers were homogeneous and stable, but that
the deposition rate and substrate temperature did have a large influence on
the properties of the layers. The results show that structural changes, first
from the collumnar structure to an amorphous structure and with a further
increase in substrate temperature, also a transition from the amorphous to a
microcrystalline structure do occure at temperatures considerably lower than
what was previously anticipated. With variations in deposition rate it was
found that the disorder in the coating will increase with an increase in rate
resulting in a reverse transition from the microcrystalline structure to the
amorphous structure. Optical gaps in the range 1. 12eV to approximately 1. 38eV
were found to be possible with the correct choice of deposition parameters...