ON THE DEGRADATION OF CONDUCTING LANGMUIR-BLODGETT-FILMS

Direct current through conducting Langmuir-Blodgett films was observed as a function of the applied voltage and alternating current as a fun ction of frequency. In some cases voltage-current characteristics appe ared to be quasi-ohmic but in other cases they exhibited tunneliing-li ke behaviour. This phenomenon was interpreted as being due to the prog ressive detachment of the film from the micro-electrodes, as confirmed by measurements of the conductivity as a function of time. This inter pretation was also confirmed by estimating the tunnelling barrier para meters from voltage-current characteristics, by conductivity measureme nts before and after thermal treatment of the samples and by conductiv ity measurements of samples stored in air and under vacuum.