High-sensitivity organic phototransistors prepared by floating film transfer method

Abstract

In this report, the performance characteristics of organic phototransistors (OPTs) prepared by the floating film transfer method (FTM) and spin coating (SC) technique are compared. The FTM OPT shows a 2-order-higher photosensitivity under an electrically induced off-state as compared with the SC OPT. Furthermore, the FTM OPT shows improved gate voltage tunabilities of photosensitivity and responsivity as compared with the SC OPT. These observed results are explained on the basis of the improved thin film morphology of the active poly(3-hexylthiophene-2,5-diyl) (P3HT) layer in the FTM OPT, pointing towards the significance of thin film processing conditions in obtaining high-sensitivity OPTs. © 2016 The Japan Society of Applied Physics.