Low-voltage organic transistors and inverters using HfOx dielectrics

Abstract

Based on the p-type pentacene and n-type N,N1-ditridecylperylene-3,4,9,10-tetracarboxylic diimide (PTCDI-C13), low-voltage organic field-effect transistors (OFETs) and inverters using hafnium (Hf)-based dielectrics were produced and characterized. All the pristine and cyclic olefin copolymer (COC)-passivated HfOx gate dielectrics were deposited by the solution-processed sol-gel chemistry, and organic thin films were deposited on the dielectrics by the neutral cluster beam deposition method. In comparison to the pristine HfOx-based OFETs, the COC-passivated transistors showed better device performance: higher hole and electron mobilities, reduced hysteresis, decreased trap densities, and particularly improved operational stability of n-type transistors. The inverters composed of the optimized p-and n-type OFETs with the asymmetric Au and LiF/Al electrodes using COC-passivated HfOx dielectrics exhibited high gains and good noise margins under ambient conditions. (C) 2015 Elsevier B.V. All rights reserved.