A Measurement of Induced Charge in CnTCNQ Langmuir-Blodgett Films Sandwiched between Aluminum Electrodes

Electrical properties of CnTCNQ Langmuir-Blodgett films sandwiched between aluminum electrodes are studied using thermally stimulated electrical measurements, and both the effect of film structure and the influence of native aluminum oxide are stressed. A change in induced charges on an electrode (Δq2) is measured while heating a sample. The relation between Δq2 and the number of deposited layers is in good agreement with a simple model based on a double-layered dielectric system. The direction of polarization in a film as deposited is also investigated using a photo-induced current measurement.