High-performance ambipolar field-effect transistors with a Ph-BTBT-10/PMMA/ZnO structure

Ambipolar field-effect transistors (FETs) are a class of transistors that transport holes and electrons simultaneously in the conducting channel, and they has extensive application prospects in various emerging fields such as synaptic, memory and logic devices. Single-component semiconductor materials such as ambipolar organic semiconductors, perovskites, black phosphorus and other materials are used as active layers for an ambipolar FET. However, it is difficult to achieve balanced transport of both holes and electrons using these materials. In this study, we designed and fabricated an ambipolar FET based on the Ph-BTBT-10/PMMA/ZnO structure in the solution process. ZnO acts as an n-type semiconductor for electron transport, and the liquid crystal small molecule Ph-BTBT-10 acts as a p-type semiconductor for hole transport. The insulating polymer PMMA is introduced by the vertical phase separation method for improving the interface of ZnO and Ph-BTBT-10. The ambipolar FET exhibits well-balanced electrical performance with hole and electron mobilities of 0.11 and 0.34 cm2 V-1 s-1. Furthermore, an inverter with a voltage gain of up to 17 V/V is demonstrated by employing two ambipolar FETs. Ambipolar FETs were designed and fabricated based on the Ph-BTBT-10/PMMA/ZnO structure by a solution process.