Yu, Seong Hun Kang, Boseok An, Gukil Kim, BongSoo Lee, Moo Hyung Kang, Moon Sung Kim, Hyunjung Lee, Jung Heon Lee, Shichoon Cho, Kilwon Lee, Jun Young Cho, Jeong Ho 2024-01-20T08:02:06Z 2024-01-20T08:02:06Z 2022-01-25 2015-01 1944-8244 https://pubs.kist.re.kr/handle/201004/125900 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. English American Chemical Society pn-Heterojunction Effects of Perylene Tetracarboxylic Diimide Derivatives on Pentacene Field-Effect Transistor Article 10.1021/am507854s 1 ACS Applied Materials & Interfaces, v.7, no.3, pp.2025 - 2031 ACS Applied Materials & Interfaces 7 3 2025 2031 N scie scopus 000348688700077 2-s2.0-84921768085 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article OXIDE GATE DIELECTRICS THIN-FILMS ELECTRICAL CHARACTERISTICS ORGANIC TRANSISTORS SEMICONDUCTOR TRANSPORT FABRICATION OPERATION LAYER pn-heterojunction charge transfer doping organic field-effect transistor perylene tetracarboxylic diimide pentacene