Interface Electronic States of Epitaxially Grown C60 on Dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene Single Crystals

• Published in: E-journal of surface science and nanotechnology Vol. 23; no. 1; pp. 44 - 50
• Main Authors: Nakayama, Yasuo, Kikuchi, Kazuhide, Yamada, Taisei, Koda, Tatsuhiro, Yamauchi, Kaname, Hattori, Hiroyuki, Ozawa, Kenichi, Mase, Kazuhiko
• Format: Journal Article
• Language: English; Japanese
• Published: Tokyo The Japan Society of Vacuum and Surface Science 01.03.2025; 公益社団法人 日本表面真空学会; Japan Science and Technology Agency
• Subjects: DNTT; Electron states; Electron transfer; Epitaxial growth; Heterojunctions; Optoelectronic devices; Organic photovoltaics; P-n junctions; Photoelectrons; PYS; Semiconductor materials; Single crystals; Spectrum analysis; Thin films; X ray photoelectron spectroscopy; XPS
• ISSN: 1348-0391; 1348-0391
• DOI: 10.1380/ejssnt.2025-011

Electronic states formed at the interfaces of molecular semiconductor materials in organic optoelectronic devices are essential for their functionality. However, resolving these states at the complex and disordered interfaces of practical devices is challenging. In this study, the electronic states at well-defined molecular semiconductor p–n heterojunctions formed by epitaxial growth of C60 on single-crystals of dinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (DNTT) were characterized by X-ray photoelectron spectroscopy and photoelectron yield spectroscopy. Our observations revealed the formation of interfacial electronic states and band bending on both sides of the heterojunction, suggesting electron transfer from DNTT to C60. Notably, these features were not revolved for conventional disordered interfaces formed on vacuum-deposited thin-films of DNTT.