Qingxin Tang, Hongxiang Li, Yaling Liu and Wenping Hu

High performance air stable n-type field-effect transistors based on single crystalline sub-micro and nanometer ribbons of copper-hexadecafluorophthalocyanine (F₁₆CuPc) were studied by using a novel device configuration. These sub-micro and nanometer ribbons were synthesized by a physical vapor transport technique and characterized by powder X-ray diffraction pattern and selected area electron diffraction pattern of transmission electron microscopy. They were found to crystallize in a structure different from that of copper phthalocyanine. These single crystalline sub-micro and nanometer ribbons could be in situ grown along the surface of Si/SiO₂ substrates during synthesis. The intimate contact between the crystal and the insulator surface generated by “in situ growing process” was free from the general disadvantages of the handpicking process for the fabrication of organic single crystal devices. High performance was observed in devices with an asymmetrical drain/source (Au/Ag) electrode configuration because in such devices a stepwise energy level between electrodes and the lowest unoccupied molecular orbital of F₁₆CuPc was built, which was beneficial to electron injection and transport. The field-effect mobility of such devices was calculated ~0.2 cm² V^-1 s^-1 with on/off ratio at ~6×10⁴. The performances of the transistors were air stable and highly reproducible.

J. Am. Chem. Soc. （2006, vol 128, 14634-14639）.

F₁₆CuPc single crystalline nanoribbons and high performance transistors.