Abstract
Sputter deposition was employed for cathode preparation in organic light emitting diodes (OLEDs). A thin film of copper phthalocyanine (CuPc) was found to be an effective buffer layer in preventing sputter damage to the OLED layer structure. However, the CuPc layer forms an electron-injection barrier with the underlying Alq layer, resulting in increased electron-hole recombination in the nonemissive CuPc layer, and thus a substantial reduction in electroluminescence efficiency. Incorporation of Li at the CuPc/Alq interface from a sputter-deposited Al (Li) cathode was found to reduce the injection barrier at the interface and make the overall device efficiency comparable to a device having an evaporated MgAg cathode. The devices exhibited good operational stability with a half lifetime greater than 3800 h at 20 mA/cm2.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
