Implementation of anti-reflection coating to enhance light out-coupling in organic light-emitting devices

• Published in: Journal of luminescence Vol. 128; no. 3; pp. 525 - 530
• Main Authors: Saxena, Kanchan, Mehta, Dalip Singh, Rai, Virendra Kumar, Srivastava, Ritu, Chauhan, Gayatri, Kamalasanan, M.N.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2008; Elsevier
• Subjects: Anti-reflection coating technique; Applied sciences; Electronics; Exact sciences and technology; Light out-coupling; Optoelectronic devices; Organic light-emitting devices; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Organic light-emitting devices; Anti-reflection coating technique; Light out-coupling; Output power; Doping; Iridium complex; Light emitting diode; Pyridine derivatives; Thickness; Biphenyl derivatives; Organic conductor; Optical coating; Magnesium fluoride; 7,7,8,8-Tetracyanoquinodimethane; Antireflection coating
• ISSN: 0022-2313; 1872-7883
• DOI: 10.1016/j.jlumin.2007.09.028

We report significant enhancement of light out-coupling in organic light-emitting devices (OLEDs) by means of anti-reflection coating of magnesium fluoride (MgF 2) on the backside of glass substrate. OLEDs were fabricated by employing the green electrophosphorescent material fac tris-(2-phenylpyridine) iridium [Ir(ppy) 3 ] doped in 4,4′,8- N, N-8-dicarbazole-biphenyl (CBP) and 0.4 wt% tetrafluorotetracyano-quinodimethane (F4-TCNQ)-doped naphthylphenylbiphenyl diamine (α-NPD) as hole transport layer (HTL). Single-layer MgF 2 with the thickness of λ/4 was then vacuum deposited on the backside of glass substrate of OLED. About two-fold enhancement in luminance with anti-reflection coating of MgF 2 has been observed.