发光层和空穴传输层对白色电致发光器件性能的影响

利用电子传输性能良好的苯并噻唑螯合锌(Zn(BTZ)₂)作为蓝光层，通过设计不同类型的空穴传输层并试验不同厚度的发光层后，制作了一种最佳厚度的双发光层白色电致发光器件：氧化铟锡(ITO)/N-N′-双(3-甲基苯基)-N-N′-二苯基-1-1′-二苯基-4-4′-二胺(TPD)∶N,N′-二(1-萘基)-N,N′-二苯基-1,1′-联苯-4-4′-二胺(NPB)(1∶0.0 关键词： 厚度 空穴传输层 白光 载流子

Effects of emitting and hole transporting layers on the performance of white organic light-emitting divice

By using Zn(BTZ)₂, an efficient material to transport electrons, as blue emitting layer, a white organic light-emitting device with the structure of indium tin oxide (ITO)/N,N′-diphenyl-N, N′-bis(3-methylphenyl)-1,1-biphenyl-4,4′-diamine) (TPD): N,N′-bis-(1-naphenyl)-N,N′-biphenyl -1,1′-biphenyl-4-4′-diamine (NPB)(1:5%)(30nm) /NPB(10nm)/ bis［2-(2-hydroxyphenyl) benzothiazolate］zinc (Zn(BTZ)₂)(30nm)/ bis(2-methyl-8-quinolinolato)(para-phenylphenolato)aluminum (BAlq)∶ 5,6,11,12-tetraphenyl-naphthacene (rubrene) (30nm)/tris(8-hydroxyquinoline)(Alq)(15nm)/Mg∶Ag has been successively made after trying several kinds of hole transporting layers and different thicknesses of emitting layers. The device can efficiently control the injecting and distributes of carriers (electrons and holes). When the voltages changes from 8 to 13V, the Commission Internationale de l′Eclairage coordinates change from (0.32，0.40) to (0.30，0.38) within the white-light region. The maximum external efficiency of this device is 0.85%, and when the driving voltage is 15V, it shows the maximum brightness of 11240cd/m². By chosing proper hole transporting layers and the best thicknesses of emitting layers, the device achieves a balance between the hole and electron injection, which is presumed to be responsible for the improved performances of the device.