The Role of BCP in Electroluminescence of Multilayer Organic Light-Emitting Devices
DENG Zhao-ru,YANG Sheng-yi*,LOU Zhi-dong,MENG Ling-chuan
Key Laboratory of Luminescence and Optical Information, Ministry of Education,Institute of Optoelectronic Technology, Beijing Jiaotong University,Beijing 100044, China
Abstract:As a hole-blocking layer, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) is usually used in blue and white light electroluminescent devices. The ability of blocking holes of BCP layer depends on its thickness, and basically holes can tunnel through thin BCP layer. In order to know the role of BCP layer in electroluminescence (EL) of multilayer organic light-emitting diodes (OLEDs), in the present paper, the authors designed a multilayer OLED ITO/NPB/BCP/Alq3∶DCJTB/Alq3/Al and investigated the influence of thickness of BCP on the EL spectra of multilayer OLEDs at different applied voltages. The experimental data show that thin BCP layer can block holes partially and tune the energy transfer between different emissive layers, and in this way, it is easy to obtain white emission, but its EL spectra will change with the applied voltages. The EL spectra of multilayer device will remain relatively stable when BCP layer is thick enough, and the holes can hardly tunnel through when the thickness of BCP layer is more than 15 nm. Furthermore, the stability of EL spectra of the multilayer OLED at different applied voltages was discussed.
邓召儒,杨盛谊*,娄志东,孟令川 . BCP在多层有机电致发光器件中的作用[J]. 光谱学与光谱分析, 2009, 29(03): 593-597.
DENG Zhao-ru,YANG Sheng-yi*,LOU Zhi-dong,MENG Ling-chuan. The Role of BCP in Electroluminescence of Multilayer Organic Light-Emitting Devices. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2009, 29(03): 593-597.
[1] Tang C W, Van Slyke S A. Appl. Phys. Lett., 1987, 51: 913. [2] Tang C W, Van Slyke S A, Chen C H. J. Appl. Phys., 1989, 65: 3610. [3] Cao Y, Parker I D, Yu G. Nature, 1999, 397: 414. [4] Chuen C H, Tao Y T. Appl. Phys. Lett., 2002, 81: 4499. [5] WANG Jin, WANG Jing, ZHENG Rong-er, et al(王 进,王 晶,郑荣儿,等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2005, 25(8): 1266. [6] WANG Jing, WANG Jin, MIAO Hong-li, et al(王 晶,王 进,苗洪利,等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2005, 25(5): 672. [7] Kido J, Shionota H, Nagai K. Appl. Phys. Lett.,1995, 67: 2281. [8] Jiang X Y, Zhang Z L, Zhang B X, et al. Synth. Met., 2002, 129: 9. [9] WEI Fu-xiang, CAO Jin, ZHANG Xiao-bo, et al(委福祥, 曹 进, 张晓波, 等). Acta Phys. Sin.(物理学报), 2006, 55: 2008. [10] Hao J G, Deng Z B, Yang S Y. Displays, 2006, 27: 108. [11] Yang S Y, Jiang Y, Teng F, et al. Solid State Commun., 2006, 139: 415. [12] Cao J, Liu X, Khan M A, et al. Current Applied Physics, 2007, 7: 300. [13] Kim Y, Im W B. Physica Status Solidi(a), 2004, 201: 2148. [14] Cheng G, Zhao Y, Li F, et al. Thin Solid Films, 2003, 467: 231. [15] ZHANG Guo-hui, HUA Yu-lin, WU Kong-wu, et al(张国辉, 华玉林, 吴空物, 等). Acta Phys. Sin.(物理学报), 2007, 56: 3559. [16] Yang S Y, Liu D, Jiang Y, et al. J. Lumin., 2007, 122-123∶ 614. [17] Deshpande R S, Bulovic V, Forrest S R. Appl. Phys. Lett., 1999, 75: 888. [18] Burrows P E, Shen Z, Bulovic V, et al. J. Appl. Phys., 1996, 79: 7991. [19] Shigeki N, Hiroyuki O, Hiroyoshi O, et al. Synth. Met., 2000, 111-112: 331.