Abstract
LB heterofilms of double layer consisting of arachic acid and 2-Pentadecy 1-7, 7', 8, 8'-Tetracyanoquinodimethane (C15•TCNQ) LB films were sandwiched between Al and Au thin evaporated films. Such layer structures of Al/LB hetero film/Au were deposited on the SiO2 insulating film of silicon wafers.
Resistance in the surface direction of the above layer structure were measured by the four point probe technique. As a result, very low resistance of 10-2-10-3Ω was obtained by the electrode system of gap 3.3mm with width 10mm. It was clarified in the experiments that the current flowed through the LB heterofilms of about 200-300A in thickness, accordingly the resistivity of LB heterofilms were calculated to be 10-8-10-9Ωcm. Such a value of resistivity was much smaller than the metal resistivity of 10-5Ωcm. Furthermore the current through the LB film was increased up to 1.3A that was equivalent to the very high current density of 4.1×105A/cm2. But the resistance was suddenly increased by 106 times at that time and the current was decreased to 3×10-4A. Such a switching phenomenon could be observed repeatedly in many times.
The ultralow resistance and the very high current density observed in the LB heterofilms will be explained by the model of the potential well filled with electron gas which was generated in the LB heterofilm by the polarization of C15•TCNQ LB film.
