An ultra-thin 5,6,11,12-tetraphenylnaphthacene(Rubrene) layer is introduced in the fabrication of a blue organic light-emitting device(OLED) with the structure of ITO/N,N′-diphenyl-N,N′-bis(1-naphthyl)-(1,18-biphenyl)-4,4′-diamine(NPB)(50 nm)/BCP(10 nm)/Rubrene(0.05 nm)/tris(8-hydroxyquinoline) aluminum(Alq3)(40 nm)/LiF(0.2 nm)/Al.The main peaks of the electroluminescent(EL) spectra of the device are located at 450 nm and 479 nm,respectively.From the photoluminescence(PL) and EL spectra of the f...