1 \chapter{Conclusions} \label{chapter_conclusion}
5 \item We fabricated a range of nanostructured metallic thin films on both Si and glass substrates using evaporative techniques. These films have been characterised using a combination of electronic and optical spectroscopy techniques.
7 \item Secondary electron microscopy analysis reveals striking differences in the structure of Au and Black Au films; Au films have been shown to consist of a regular periodic array of nanoparticles, whilst Black Au appears to consist of a highly randomised, porous mix of strand like structures.
9 \item A Total Current Spectroscopy experiment for characterisation of samples in situ has been integrated with the technology for sample preparation. We used this setup to investigate elastic scattering of electrons as a function of film deposition.
11 \item Results for Black metal films deposited on existing layers of metal films suggest that the Black metal films present a sharper, more step like potential barrier to the primary electrons.
12 \item Further improvements may be made to the Total Current Specroscopy experiment with a possibility to investigate inelastic scattering processes occuring in the metallic thin films.
16 The optical properties of Black Au have been investigated and compared with those of Au.
18 \item Transmission spectroscopy experiments support existing evidence for a plateau in the infra-red.
19 \item We found a minima in the transmission spectrum of a Black Au film at around $370$nm; this minima is absent in the spectrum of a similar thickness Au film.
22 \item Ellipsometry has been used to determine the optical constants of thin films of Ag and Black Ag. These results show a significant peak in both the refractive index and extinction coefficient of the Black Ag film in the region of $350$ to $400$nm. These peaks are absent for the Ag sample.