Organic interfaces of rubrene single crystals (RSCs) in ion gel-gated electric double-layer transistors (EDLTs) were investigated by electron spin resonance (ESR). The EDLTs were fabricated by laminating ion-gel films onto RSCs. Clear ESR signals due to field-injected holes in RSCs were successfully observed at low gate voltages, showing a high spin concentration due to the high capacitance of EDLTs. The analyses of anisotropic ESR signals and its gate-voltage dependence show that the bulk molecular orientation at RSCs' interfaces is preserved without forming deep trapping levels, which demonstrate that organic interfaces in RSC-EDLTs are clean and undamaged under a strong electric field in EDLTs.
ASJC Scopus subject areas
- Physics and Astronomy(all)