Zinc-Tin oxide/C8-BTBT hybrid heterostructures providing balanced ambipolar charge transport behaviors and their applications to pre-state-dependent inverter logic

Abstract

Ambipolar charge transport is promising for developing new electron applications. In this research, a high-performance ambipolar thin-film transistor (TFT) with an inorganic-organic heterostructure was developed using zinc-tin-oxide (ZTO) and 2,7-dioctyl [1]benzothieno [3,2-b] [1]benzothiophene (C8-BTBT). The device exhibited textbook-like V-shaped transfer curves of ambipolar TFTs with a uniformly changing transition voltage (VTR) according to the applied drain voltage (VD). This behavior appears symmetrically in both hole-and electron-dominant regions, which is desirable for complementary-like ambipolar circuit operation. Furthermore, an inverter circuit with hysteresis characteristics was demonstrated using the same organic-inorganic hetero-structure ambipolar TFTs. Owing to the hysteresis behavior, a previous-state-dependent logic inverter circuit (PDC) that outputs a different logic value depending on the previous value was successfully implemented, and the pulse operation of the fabricated PDC was demonstrated.