Abstract：The blue top-emitting organic light-emitting devices with cavity effect have been fabricated. The authors used the TBADN∶ 3%DSAPh as emitting material of blue microcavity OLEDs. The devices consisted of Ag/ITO/CuPc/NPB/TBADN∶ 3%DSAPh/Alq3/LiF/Al(Ag) structure. On a patterned glass substrate, silver was deposited as reflective anode, and copper phthalocyanine (CuPc) layer as HIL and 4’-bis[N-(1-Naphthyl)-N-phenyl-amino] biphenyl (NPB) layer as HTL were made. Aluminum and silver thin films were made as semi-transparent cathode. The transmittance of aluminum and silver (Al/Ag) cathode was about 30%. In EL spectrum, the full width at half maximum (FWHM) was only 17nm. By changing the thicknesses of ITO, highly saturated color with Commission Internationale de L’Eclairage chromaticity coordinates (CIEx,y) of (0.141, 0.049) was obtained. In the present article, the emission intensity of spectrum was studied. An appropriate cathode transmittance will result in maximal emission intensity. By using the formula of microcavity, the approximative curve that describes the change of emission intensity with cathode transmittance (or reflectance) was figured out.
[1] Djurisic’ A B, Kwong C Y, Cheung C H, et al. Chemical Physics Letters, 2004, 399: 446. [2] Tang C W, VanSlyke S A, Chen C H. J. Appl. Phys., 1989, 65: 3610. [3] ZHU Wen-qing, WU You-zhi, ZHENG Xin-you, et al(朱文清, 吴有智, 郑新友, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2005, 25(4): 509. [4] LI Hong-jian, QU Shu, XU Xue-mei, et al(李宏建, 瞿 述, 许雪梅, 等). Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2002, 22(2): 189. [5] Burrows P E, Gu G, Bulovic' V, et al. IEEE Trans. Electron Devices, 1997, 44: 1188. [6] Shen Z, Burrows P E, Bulovic' V, et al. Science, 1997, 276: 2009. [7] Burrows P E, Shen Z, Forrest S R, 1997 International Display Research Conference, Record, Toronto, Sept., 1997. 318. [8] Hsu S F, Chung-Chun Lee, Andrew T Hu. Current Applied Physics, 2004, 4: 663. [9] Lee J H, Nam W J, Han S M, et al. Han, SID 03 Digest, 2003. 490. [10] Goh J C, Kim C K, Jang J. SID 03 Digest, 2003, 494. [11] Dodabalapur A, Rothberg L J, Jordan R H, et al. J. Appl. Phys., 1996, 80: 6954. [12] Neyts K, de Visschere P, Fork D K, et al. Anderson, J. Opt. Soc. Am. B17, 2000. 114. [13] Qiu F, Peng H J, Chen H Y, et al. IEEE Trans. Electron Devices, 2004, 51: 1208. [14] Dodabalapur A, Rothberg L J, Miller T M, et al. Appl. Phys. Lett., 1994, 64(19): 2486. [15] Schubert E F, Hunt N E J, Micovic M, et al. Science, 1994, 265: 943. [16] Dodabalapur A, Rothberg J L, Miller T M, et al. Appl. Phys. Lett., 1994, 64: 2486.
