Performance enhancement of pentacene and F16CuPc-based low-voltage devices using cross-linked blend gate dielectrics

Abstract

Herein is reported the fabrication and systematic comparative analysis of low-voltage organic filed-effect transistors (OFETs) and inverters using bare ZrOx dielectrics and inorganic-organic hybrid CZB (cross-linked ZrOx/1,6-bis(trimethoxysily)hexane blend) dielectrics. Solution-processed sol-gel chemistry was employed to prepare the gate dielectrics. Two active layers of p-type pentacene and n-type copper hexadecafluorophthalocyanine (F16CuPc) were deposited on the dielectrics using the neutral cluster beam deposition method. Compared with bare ZrOx-based transistors and inverters, the CZB-based devices with low leakage current and high capacitance exhibited significantly higher hole and electron carrier mobilities of (0.12 --> 1.03) and (1.3 x 10(-3) --> 4.9 x 10(-3)) cm(2) (Vs)(-1), respectively, and enhanced gains of (9.4 --> 13.3), together with large output voltage swings and sharp inversions in the voltage transfer characteristics (VTCs). The CZB-based inverters also exhibited improved noise margins due to the higher gain and better symmetry of the VTCs compared with their bare ZrOx-based counterparts. The results indicate that on the basis of the enhanced electrical properties of CZB dielectrics and the growth of high-quality crystalline semiconducting films on CZB dielectric surfaces, such high-performance devices operating at low voltage levels are promising potential components for integrated circuits.