Effect of encapsulation on OLED characteristics with anisotropic conductive adhesive

Organic light emitting devices (OLEDs) is one of the most potentially interesting display technologies in the flat panel display (FPD) field. This paper investigates the effects of OLED structures and a perimeter encapsulation to protect the OLED from atmospheric exposure. Firstly, the electric features of the OLED devices with and without a copper phtalocyanine layer were measured, and the one with the additional buffer layer showed a lower turn-on voltage. Then the OLED device sample was encapsulated with a glass cover bonded to the substrate with an adhesive matrix containing micro-particles. The samples were stored in ambient conditions, and the IV characteristics were studied with shelf-time as a parameter. The measurement results indicated that the encapsulation had a significant improvement on the device operation. After two weeks of storage the encapsulated samples showed less degradation and the current density at a given operating bias was about fifty percent higher than without encapsulation.