Fabrication and characterization of Schottky barrier diodes with tetracyanoquinodimethane doped with bis(β-naphthyl)-tetrathiafulvalene

Stable Schottky barrier diodes with tetracyanoquinodimethane doped with 5% by weight bis(β-naphthyl)-tetrathiafulvalene as active ndoped semiconductor have been fabricated by physical vapor deposition. Gold and aluminum were used as ohmic and Schottky contacts, respectively. An ideality factor of 3.5 was deduced from current-voltage measurements. Several cycles of voltage sweeping were necessary before the diodes showed optimal characteristics. Charge migration is most likely the dominating mechanism behind this phenomenon. From capacitance-voltage measurements, at different frequencies, a charge carrier concentration of 2.2 × 1016 cm−3 was determined. A high charge carrier mobility of 14 cm2 V−1 s−1 was deduced. These devices showed no degradation after a month of storage in a laboratory environment.