Fabrication and characteristics of permeable-base organic transistors based on co-evaporated pentacene:Al base

In this letter, fabrication and characteristics of a p-type permeable-base organic transistor are reported. A hole-type organic semiconductor pentacene is used as emitter and collector. The permeable pentacene:Al base is formed by co-evaporating pentacene and Al in vacuum. The device performance has shown to depend on the evaporation rate of pentacene in the pentacene: Al co-evaporation, where the evaporation rate of Al is controlled at 1 nm/s. Controlling the evaporation rate of pentacene at 0.1 nm/s in the pentacene: Al co-evaporation, the device shows the optimal common-base current gain of near 1 and common-emitter current gain of similar to 137. (C) 2011 Elsevier B.V. All rights reserved.