表面处理提高绿色OLED外量子效率研究

Research to improve out-coupling efficiency of green organic light-emitting devices based on surface treatment

该文通过喷砂打磨技术使器件的表面粗糙化,有效地压制了玻璃层内的光波导,促进光子在玻璃-空气界面的散射,大幅度提高了有机绿色发光器件的输出耦合效率。有机绿色电致发光器件的流明效率、外量子效率分别提高到44.9 cd·A-1、15.4%,提高率达到54.0%。当粗糙度介于1~4μm之间时,器件的输出耦合效率提高率随着表面粗糙度的减小而提高。同时,粗糙表面对发光器件的朗伯体特性没有带来任何影响。

The authors modified the device surfaces from smooth to rough based on the sandblasting process. The rough surface effectively suppresses the optical waveguide in the glass layer, promoting photon scattering in the glass-air interface, thereby significantly improves output coupling efficiency of GOLED. The GOLED＇s luminous efficiency and external quantum efficiency was raised to 44.9 cd·A^-1 and 15.4%, respectively, the improvement rate reached to 54.0%. Furthermore, the improvement of the out-coupling efficiency is monotonously decreasing with the surface roughness within the roughness range from around 1 μm to 4 μm. At the same time, there has not caused any effect to the Lambertian characteristics of the lighting devices by the rough surface. The technology provides the opportunity for large-area applications.