Ambipolar organic heterojunction transistors based on F₁₆CuPc/CuPc with a MoO₃ buffer layer

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.