Encapsulation Technologies

Abstract

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.