OLED Anode Segmentation for Electron Injection and Low Resistance

The electrode is divided into multiple functional layers: a first layer with low work function material (Yb, Ca, Ba, Sr) for electron injection, a second layer with low resistivity material (Al, Ag, Mo, W) for current conduction, and optionally a third layer with low work function material for protection and additional electron injection. This segmentation allows each layer to optimize its specific function, achieving both low resistance and high electron injection efficiency.

The electrode uses composite material structure combining different materials with complementary properties. The low work function materials (e.g., Yb, Ca, Ba, Sr) are combined with low resistivity metals (e.g., Al, Ag, Mo, W) to create an electrode that simultaneously achieves excellent electron injection capability and low electrical resistance, resolving the contradiction between injection efficiency and resistance.

The electrode combines transparent conductive oxide (ITO, IZO, IGZO) with low work function materials (Yb, Ca, Ba, Sr) and low resistivity metals (Al, Ag, Mo, W) in a composite structure. The transparent conductive oxide layer maintains light transmittance, while the low work function and low resistivity metal layers provide excellent electron injection and current conduction, respectively, achieving both optical transparency and low resistance.

The electrode is segmented into multiple layers where the transparent conductive oxide layer handles light transmission, the low work function layer handles electron injection, and the low resistivity metal layer handles current conduction. This functional segmentation allows each layer to optimize its specific property without compromising the others.

The electrode is segmented so that the low work function material layer is positioned specifically at the interface with the emission layer to maximize electron injection, while the low resistivity metal layer with better optical properties handles the bulk current conduction. This spatial segmentation allows the low work function material to perform its injection function without excessive light absorption in the light-emitting path.

The low work function material (Yb, Ca, Ba, Sr) is applied locally at the electrode-emission layer interface where electron injection is needed, rather than throughout the entire electrode structure. This localized application provides high electron injection efficiency at the critical interface while minimizing overall light absorption in the electrode.