Multilayer n-Type Organic Metal-Base Transistor

We have studied the effects of the fullerene C₇₀ on the device performance of a composite-emitter multilayer metal-base transistor (MBT). It is shown that the higher molecular weight leads to high common-emitter current gain β of over 252 in a wide range of collector-emitter voltage. By selecting an appropriate maximum and minimum base current IB, an on-to-off current ratio 4.73 × 10⁶ is achieved. This is a substantial improvement over an identical MBT employing C₆₀ having β = 8 and on-to-off current ratio 4.25.