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

Stable Schottky barrier diodes with tetracyanoquinodimethane doped with 5% by weight bis(beta-naphthyl)-tetrathiafulvalene as active n-doped 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 x 10(16) cm(-3) was determined. A high charge carrier mobility of 14 cm(2) V-1 s(-1) was deduced. These devices showed no degradation after a month of storage in a laboratory environment.