氧等离子体处理改善ITO电极表面湿润性

Improving Surface Wettability of ITO Electrode for OLED with Oxygen Plasma

采用氧等离子体处理对有机发光器件ITO电极进行表面改性,基于接触角的测量,利用几何平均法计算了ITO的表面能和极性度,研究了氧等离子体处理对ITO电极表面湿润性的影响。实验数据和计算结果表明:氧等离子体处理后,ITO表面极性度增加,表面能增大,接触角减小,其表面湿润性得到很大改善。同时,进一步研究了氧等离子体处理对有机发光器件性能的影响,结果显示:ITO电极表面湿润性的改善,提高了发光亮度和效率,降低了启亮电压和驱动电压,有效地改善了器件的光电性能。

Surface modification of the indium tin oxide （ITO） electrodes for organic light emitting devices （OLEDs） was carried out with oxygen plasma treatment. Based on the measurements of the contact angles,the surface energy and surface polarity of the ITO electi＇odes were calculated using the geometric mean approach. The effect of oxygen plasma treatment on the surface wettability of ITO electrodes was investigated. The experimental data and calculated results show that the oxygen plasma enhances surface polarity, increases surface energy and decreases contact angle,and therefore improves effectively surface wettability of ITO electrodes. Furthermore,the influence of surface modification of the ITO electrodes on the characteristics of OLEDs is studied. The oxygen plasma treated devices exhibits higher electroluminescence luminance and efficiency, and smaller turn-on voltage and driving voltage, due to the effective improvement of the surface wettability of the ITO electrodes.