Ambipolar organic heterojunction transistors based on F16CuPc/CuPc with a MoO3 buffer layer**Project supported by the National Natural Science Foundation of China (Nos. 61475074, 61204095).

Abstract

We fabricated heterojunction organic field-effect transistors (OFETs) using copper phthalocyanine (CuPc) and hexadecafluorophtholocyaninatocopper (F16CuPc) as hole transport layer and electron transport layer, respectively. Compared with F16CuPc based OFETs, the electron field-effect mobility in the heterojunction OFETs increased from 3.1 × 10−3 to 8.7 × 10−3 cm2/(V·s), but the p-type behavior was not observed. To enhanced the hole injection, we modified the source–drain electrodes using the MoO3 buffer layer, and the hole injection can be effectively improved. Eventually, the ambipolar transport characteristics of the CuPc/F16CuPc based OFETs with a MoO3 buffer layer were achieved, and the field-effect mobilities of electron and hole were 2.5 × 10−3 and 3.1 × 10−3 cm2/(V·s), respectively.