High quality boron doped diamond electrodes have been fabricated with a wide range of boron doping levels.
Ohmic diamond-titanium contacts were made by depositing the diamond films on top of a partially titanium coated silicon substrate. The electrical behaviour of these contacts was measured and compared to traditional top contacts. These novel titanium undercontacts provided a superior response and also significantly simplified the processing required to fabricate low doped diamond electrodes.
Reversible electrochemistry was seen on highly doped diamond electrodes.
AC impedance measurements have shown that electron transfer across the interface occurs via a surface state.
The electrochemistry of low doped diamond films has been shown to be highly dependent on surface termination. Hydrogen terminated diamond electrodes have exhibited reversible behaviour while oxygen terminated diamond electrodes have shown limited cathodic currents. These results are discussed in relation to a surface state mediated electron transfer mechanism.
Photocurrent spectroscopy; and intensity modulated photocurrent spectroscopy (IMPS) studies were performed.
Polycrystalline diamond with low boron doping levels was shown to behave as a p-type semiconductor.