Photoconduction and photovoltaic effects in Pentacene based on thin film organic phototransistor

Abstract

In this paper, Pentacene thin film phototransistors were fabricated and characterized. The magnitude of the photocurrent induced by illumination was found to be the result of two distinct effects: photovoltaic effect, which the photocurrent related to electron-hole pair generation, and photoconductor effect, that the current enhancement caused by a threshold voltage shift. The electrical parameters such as mobility µ, threshold voltage Vth, the Ion/Ioff ratio, the subthreshold S, the interface density of trap Dit, the total trap density Ntrap, and the photoresponse R value were determined. The effect of white light illumination where investigated.