Benzohexacene guide in accurate determination of field effect carrier mobilities in long acenes

• Published in: RSC advances Vol. 12; no. 2; pp. 671 - 68
• Main Authors: Bedel Pereira, E, Bassaler, J, Laval, H, Holec, J, Monflier, R, Mesnilgrente, F, Salvagnac, L, Daran, E, Duployer, B, Tenailleau, C, Gourdon, A, Jancarik, A, Séguy, I
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 22.12.2021; The Royal Society of Chemistry
• Subjects: Carrier mobility; Charge transport; Chemistry; Condensed Matter; Current carriers; Electronic devices; Engineering Sciences; Hole mobility; Materials Science; Micro and nanotechnologies; Microelectronics; Physics; Semiconductor devices; Thin film transistors; Thin films; Transistors
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/d1ra07808a

Oligoacenes are promising materials in the field of electronic devices since they exhibit high charge carrier mobility and more particularly as a semiconductor in thin film transistors. Herein, we investigate the field effect charge carrier mobility of benzohexacene, recently obtained by cheletropic decarbonylation at moderate temperature. Initially, high performance bottom contact organic thin-film transistors (OTFTs) were fabricated using tetracene to validate the fabrication process. For easier comparison, the geometries and channel sizes of the fabricated devices are the same for the two acenes. The charge transport in OTFTs being closely related to the organic thin film at the dielectric/organic semiconductor interface, the structural and morphological features of the thin films of both materials are therefore studied according to deposition conditions. Finally, by extracting relevant device parameters the benzohexacene based OTFT shows a four-probe contact-corrected hole mobility value of up to 0.2 cm 2 V −1 s −1 . Four-probes mobility vs. V GS in the linear regime ( V DS = −10 V) for benzohexacene based transistor.