Pn-heterojunction effects of perylene tetracarboxylic diimide derivatives on pentacene field-effect transistor

Seong Hun Yu, Boseok Kang, Gukil An, Bongsoo Kim, Moo Hyung Lee, Moon Sung Kang, Hyunjung Kim, Jung Heon Lee, Shichoon Lee, Kilwon Cho, Jun Young Lee, Jeong Ho Cho

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

We investigated the heterojunction effects of perylene tetracarboxylic diimide (PTCDI) derivatives on the pentacene-based field-effect transistors (FETs). Three PTCDI derivatives with different substituents were deposited onto pentacene layers and served as charge transfer dopants. The deposited PTCDI layer, which had a nominal thickness of a few layers, formed discontinuous patches on the pentacene layers and dramatically enhanced the hole mobility in the pentacene FET. Among the three PTCDI molecules tested, the octyl-substituted PTCDI, PTCDI-C8, provided the most efficient hole-doping characteristics (p-type) relative to the fluorophenyl-substituted PTCDIs, 4-FPEPTC and 2,4-FPEPTC. The organic heterojunction and doping characteristics were systematically investigated using atomic force microscopy, 2D grazing incidence X-ray diffraction studies, and ultraviolet photoelectron spectroscopy. PTCDI-C8, bearing octyl substituents, grew laterally on the pentacene layer (2D growth), whereas 2,4-FPEPTC, with fluorophenyl substituents, underwent 3D growth. The different growth modes resulted in different contact areas and relative orientations between the pentacene and PTCDI molecules, which significantly affected the doping efficiency of the deposited adlayer. The differences between the growth modes and the thin-film microstructures in the different PTCDI patches were attributed to a mismatch between the surface energies of the patches and the underlying pentacene layer. The film-morphology-dependent doping effects observed here offer practical guidelines for achieving more effective charge transfer doping in thin-film transistors.

Original languageEnglish
Pages (from-to)2025-2031
Number of pages7
JournalACS Applied Materials and Interfaces
Volume7
Issue number3
DOIs
Publication statusPublished - 2015 Jan 28

    Fingerprint

All Science Journal Classification (ASJC) codes

  • Materials Science(all)

Cite this

Yu, S. H., Kang, B., An, G., Kim, B., Lee, M. H., Kang, M. S., Kim, H., Lee, J. H., Lee, S., Cho, K., Lee, J. Y., & Cho, J. H. (2015). Pn-heterojunction effects of perylene tetracarboxylic diimide derivatives on pentacene field-effect transistor. ACS Applied Materials and Interfaces, 7(3), 2025-2031. https://doi.org/10.1021/am507854s