Flexible organic light emitting diode (OLED) display is an exciting and
attractive technology to the consumers and the manufacturers, but there still exists a
few challenges before it comes into real application. The biggest challenge is the
demanding water and oxygen permeation requirement of the encapsulation, since the
lifetime of OLED will drastically decrease when it is exposed to moisture and oxygen.
As the barrier performance of polymer is not as good as that of glass, both sides of the
OLED device which is deposited on polymer substrate need to be encapsulated by
dense thin films. This chapter will provide a summary of the encapsulation technologies,
including the traditional encapsulation and the advanced thin film encapsulation.
First, the degradation mechanism, the permeation mechanism, and the permeation
measurement are introduced as background information. Then thin film encapsulation
technologies (Vitex organic/inorganic multilayer and atomic layer deposited film) will
be the main topic.
Keywords: Atomic layer deposition, Barrier, Ca test, Dark spots, Degradation,
Encapsulation, Flexible display, Getter, Glass or metal lid, Lifetime, Moisture,
Multilayer, Nanocomposite film, Oxygen, Permeation, Water vapor transmission
rate.