Growth of rubrene crystalline thin films using thermal annealing on DPPC LB monolayer

High crystalline thin films of 5,6,11,12-tetraphenylnaphthacene (rubrene) can be obtained after in situ thermal post annealing using SiO₂ gate dielectric modified with a 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) monolayer obtained via Langmuir–Blodgett transfer. Such formed rubrene crystalline films are interconnected and highly ordered with defined molecular orientation. Organic thin film transistors (OTFTs) with high performance are reproducibly demonstrated with the mobility of 0.98 cm²/V s, the threshold voltage of −8 V and the on–off current ratio of higher than 10⁷. The results indicate that our approach is a promising one for preparing high quality rubrene crystalline films.