柔性与玻璃衬底OLED性能的比较研究

Comparison of OLEDs on glass and flexible polymers

采用真空热蒸发法分别制备出柔性衬底和玻璃衬底ITO/TPD/Alq/Al结构有机电致发光器件(OLED)。利用原子力显微镜研究了玻璃衬底及柔性衬底ITO膜的表面形貌的差异。研究了玻璃衬底及柔性衬底OLED的工作电压、发光效率等性能,发现两者的起亮电压相差不大,后者的B-I曲线具有更好的线性关系,发光性能和电流特性与前者相比则存在较大差距;还对柔性衬底OLED性能较差的原因进行了深入分析。

ITO/TPD/Alq/Al structure of OLEDs on glass and flexible polymer was made by vacuum evaporation method. The surface topographic images of ITO films on glass and flexible polymer were investigated by atomic force microscopy （AFM）. The characteristics of OLEDs with various organic layer thickness were investigated, such as operating voltage and electroluminescent efficiency. It was found that the flexible OLEDs had the same turn-on voltages with OLEDs on glass substrates. The OLEDs on flexible OLEDs had more linear B-I curves. The glass substrates had larger luminance while the origination of lower luminance of flexible OLEDs is discussed in detail in the paper.