White Organic Light-Emitting Devices with Ultra-High Color Stability over Wide Luminance Range
White Organic Light-Emitting Devices with Ultra-High Color Stability over Wide Luminance Range
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DOI：
10.1016/j.orgel.2010.12.019
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发表时间：
2011-03
影响因子：
3.2
通讯作者：
C. Hsiao;Yi-Hsin Lan;Pei-Yu Lee;Tien‐Lung Chiu;Jiu-Haw Lee
中科院分区：
文献类型：
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作者：
C. Hsiao;Yi-Hsin Lan;Pei-Yu Lee;Tien‐Lung Chiu;Jiu-Haw Lee
通过引入适当的带有间隔层的发射层（EML）结构，并设计具有选择性掺杂分布的蓝色EML（B-EML），获得了具有超高颜色稳定性的白色有机发光器件（WOLED）。选择性掺杂分布相对于常规均匀掺杂分布的优点是使在具有较低激子能量的掺杂剂上的直接激子形成最小化，以抑制电致发光（EL）光谱变化。复合区位于侧墙/B-EML界面处，宽度为4.5nm。在选择性掺杂的情况下，WOLED表现出超高的颜色稳定性，其中CIE坐标从200 nm偏移到200 nm。（0.399，0.483）至（0.395，0.479）随着亮度从145增加到12，100 cd/m2，（0.401，0.481）到（0.400，0.479），亮度从1240增加到4850 cd/m2，显示器和照明应用的实际亮度范围。除了在大约两个数量级的宽亮度范围内的小CIE坐标变化（-0.004，-0.004）之外，我们还实现了34.1cd/A的高器件效率，在2000 cd/m2以下保持大于30 cd/A。
A white organic light-emitting device (WOLED) with ultra-high color stability was achieved by introducing an appropriate emitting layer (EML) structure with a spacer, and engineering a blue EML (B-EML) with a selectively doped profile. The advantage of the selectively doped profile over the conventional, uniformly doped profile was to minimize direct exciton formation on dopants with lower exciton energies to suppress electroluminescence (EL) spectrum variations. The recombination zone was found to be located at the spacer/B-EML interface, with a width of 4.5nm. With the selectively doped profile, the WOLED exhibited ultra-high color stability, with the CIE coordinates shifting from (0.399, 0.483) to (0.395, 0.479) as the luminance increased from 145 to 12,100cd/m2and from (0.401, 0.481) to (0.400, 0.479) as the luminance increased from 1240 to 4850cd/m2, the practical luminance range for display and lighting applications. In addition to the small CIE coordinates variation of (−0.004, −0.004) over the broad luminance range of about two orders of magnitude, we also achieved a high device efficiency of 34.1cd/A, which stayed larger than 30cd/A below 2000cd/m2.