Resists, Recording Materials and Fabrication of Patterns

A j-n-heterojunction type device can be fabricated on the basis of the junction formed between polypyrrole and PT derivatives, e.g. PT itself or 3-methylPT [128]. A 3-octa-decylPT/ fullerene Cgo junction device with a photo-induced charge transfer between 3-octadecylPT and fullerene Ceo is prepared in the following way a quartz plate is coated with a gold electrode, a layer of 3-alkylPT is brought up, followed by a layer of fullerene Ceo and at the end a layer of alumina as the second electrode [129]. 

Rectifying bilayer electrodes with sequential bilayer structures are prepared from any pair of 3-butylPT/polypyrrole and 3-bromoPT/polypyrrole by anodic electropolymerization on platinum electrodes [130]. 

In contrast to the above described process, thin films of soluble 3-hexylPT can be cross-linked and thus be made insoluble by radiation with UV/visible light [132, 133], Irradiation of thin polymeric films through a photomask and subsequent development with a suitable solvent leaves a polymer image of the mask. The resulting polymer pattern can be made electrically conductive by a chemical oxidation process. Such electronically conductive channels can be fabricated using conventional photolithographic techniques. 

Polysilane films treated with thiophene can be polymerized electrochemically on an indium tin oxide (ITO) glass electrode as an insoluble film under a pattern in such areas without UV light irradiation, whereas the polysilane film in such areas irradiated with UV light can be dissolved in a polar solvent such as propylene carbonate [134]. 

3-HexylPT films containing diphenyliodonium hexafluoroarsenate are used for optical recording by light irradiation followed by washing with chloroform [135]. 

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