Chemical Vapor-Deposited Hexagonal Boron Nitride as a Scalable Template for High-Performance Organic Field-Effect Transistors

Abstract

Organic field-effect transistors have attracted much attention because of their potential use in low-cost, large-area, flexible electronics. High-performance organic transistors require a low density of grain boundaries in their organic films and a decrease in the charge trap density at the semiconductor-dielectric interface for efficient charge transport. In this respect, the role of the dielectric material is crucial because it primarily determines the growth of the film and the interfacial trap density. Here, we demonstrate the use of chemical vapor-deposited hexagonal boron nitride (CVD h-BN) as a scalable growth template/dielectric for high-performance organic field-effect transistors. The field-effect transistors based on C60 films grown on single-layer CVD h-BN exhibit an average mobility of 1.7 cm2 V-1 s-1 and a maximal mobility of 2.9 cm2 V-1 s-1 with on/off ratios of 107. The structural and morphology analysis shows that the epitaxial, two-dimensional growth of C60 on CVD h-BN is mainly responsible for the superior charge transport behavior. We believe that CVD h-BN can serve as a growth template for various organic semiconductors, allowing the development of large-area, high-performance flexible electronics.