Hybrid metal-base transistor with base of sulfonated polyaniline and fullerene emitter

We demonstrate hybrid vertical architecture transistors that operate like metal-base transistors, using n-type silicon as the collector, sulfonated polyaniline as the base, and C-60 fullerene as the emitter. Electrical measurements suggest that the sulfonated polyaniline base effectively screens the emitter from electric field variations occurring in the collector leading to the metal-base transistor behavior. These devices operate at low voltages and show common-emitter current gain equal to 8, which is independent of the base current up to values of similar to 1.5 mu A and constant at collector voltages between 1 and 5 V.