Multilayered cathode structures having silver for OLED devices
View Patent ↗A cathode structure for use in an OLED device having one or more OLED layers includes a thin light-transmissive layer having a top surface and a bottom surface and including silver (Ag) wherein the Ag acts as a conductor for the cathode structure, and a light-transmissive electron-injecting layer disposed in contact with the bottom surface of the thin light-transmissive layer and with an underlying OLED layer. The structure also includes an oxide layer disposed over the thin light-transmissive layer, and a separation layer disposed between the top surface of the thin light-transmissive layer and the oxide layer.
1. A cathode structure for use in an OLED device having one or more OLED layers, comprising:
a) a thin light-transmissive layer having a top surface and a bottom surface and including silver (Ag) wherein the Ag acts as a conductor for the cathode structure;
b) a light-transmissive electron-injecting layer disposed in contact with the bottom surface of the thin light-transmissive layer and with an underlying OLED layer;
c) an oxide layer disposed over the thin light-transmissive layer; and
d) a separation layer disposed between the top surface of the thin light-transmissive layer and the oxide layer for impeding reaction between the oxide layer and the silver in the light transmissive layer.
2. The cathode structure of claim 1 wherein the electron-injecting layer includes two or more sublayers.
3. The cathode structure of claim 2 wherein the two or more sublayers of the electron-injecting layer each include a low work function material having a work function less than 4 eV.
4. The cathode structure of claim 3 wherein the low work function material includes Mg, Ag, Li, LiF/Al, Rb, Cs, Yb, Ba, CaAl, MgAl, Li/Al, or Li 2 O/Al, or combinations thereof.
5. The cathode structure of claim 1 wherein the electron-injecting layer is a single layer having a low work function material having a work function less than 4 eV.
6. The cathode structure of claim 5 wherein the low work function material includes Mg, Ag, Li, LiF/Al, Rb, Cs, Yb, Ba, CaAl, MgAl, Li/Al, or Li 2 O/Al, or combinations thereof.
7. A cathode structure for use in an OLED device having one or more OLED layers, comprising:
a) a thin light-transmissive layer having a top surface and a bottom surface and including Ag wherein the Ag acts as a conductor for the cathode structure;
b) a light-transmissive electron-injecting layer disposed in contact with the bottom surface of the thin light-transmissive layer and with an underlying OLED layer;
c) an oxide layer disposed over the thin light-transmissive layer and
d) a separation layer including Al, Ti, Mg, Zn, Sn, In, Au, Li, or Ca, or combinations thereof disposed between the top surface of the thin light-transmissive layer and the oxide layer for impeding reaction between the oxide layer and the silver in the light transmissive layer.
8. The cathode structure of claim 7 wherein the electron-injecting layer includes two or more sublayers.
9. The cathode structure of claim 8 wherein the two or more sublayers of the electron-injecting layer each include a low work function material having a work function less than 4 eV.
10. The cathode structure of claim 9 wherein the low work function material includes Mg, Ag, Li, LiF/Al, Rb, Cs, Yb, Ba, CaAl, MgAl, Li/Al, or Li 2 O/Al, or combinations thereof.
11. The cathode structure of claim 7 wherein the electron-injecting layer is a single layer having a low work function material having a work function less than 4 eV.
12. The cathode structure of claim 11 wherein the low work function material includes Mg, Ag, Li, LiF/Al, Rb, Cs, Yb, Ba, CaAl, MgAl, Li/Al, or Li 2 O/Al, or combinations thereof.