High performance lead phthalocyanine films and its effect on the field-effect transistors

The film morphology, structure, and electrical properties of lead phthalocyanine (PbPc) epitaxially grown on 5,5″-bis(3′-fluoro-biphenyl-4-yl)-2,2′:5′,2″-terthiophene (m-F2BP3T) inducing layer substrates were systematic investigated. The morphologies of PbPc films sensitively depend on the thickness of the inducing layer and substrate temperature. All the epitaxial PbPc films with high quality presented the triclinic form with a variation of the out-of-plane orientation. The field-effect mobility of the epitaxial PbPc films was 0.05–0.31 cm2/V s, which was significantly improved by 1–2 orders of magnitude compared to the traditional films. The evolution of the device performance is the synergistic effect of the morphology and out-of-plane orientation of the triclinic form of PbPc. The higher quality of the films and the smaller ratio of (1 0 0)/(0 0 1), the higher device performance is. A clear relationship between the morphology, structure, and the performance of epitaxial PbPc-based organic field-effect transistors was reported.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► High quality PbPc films with large grain size and well continuity are obtained. ► The crystalline films are composed of uniform triclinic form PbPc crystals. ► The films show the highest mobility of 0.31 cm2/V s in optimized devices.