Development and characterisation of polypyrrole/metal junctions for electronic applications

Preliminary results are presented on the fabrication and analysis of junctions formed between metals and semi‐conducting and conducting polypyrrole. Rectifying junctions were observed between aluminium and indium with semi‐conducting polypyrrole in a sandwich geometry using current‐voltage ( I‐V ) and capacitance‐voltage ( C‐V ) analysis techniques, respectively. All planar junctions analysed were non‐rectifying, while both gold and platinum were observed to form ohmic junctions in both the sandwich and planar geometries. Preliminary analysis using ideal Schottky barrier theory was attempted with various junction parameters determined, with significant deviation from the ideal theory observed. It is proposed that this deviation is due to the synthesis history of the polymer and the presence of an insulating oxide layer between the polymer and the metal.