Characteristics of Al2O3/ZrO2 laminated films deposited by ozone-based atomic layer deposition for organic device encapsulation

We investigated the characteristics of 100 nm-thick Al 2 O 3 /ZrO 2 laminated films grown by ozone (O 3 )-based atomic layer deposition (ALD) at low temperature (100 °C) as thin film encapsulation (TFE). Calcium (Ca) test was performed at a relative humidity (RH) of 50% with a temperature of 50 °C to derive the water vapor transmission rates (WVTRs) of aluminum oxide (Al 2 O 3 )-, zirconium oxide (ZrO 2 )-, and Al 2 O 3 /ZrO 2 -laminated films. Al 2 O 3 /ZrO 2 -laminated films exhibited better permeation barrier properties than Al 2 O 3 or ZrO 2 single layer films. In Al 2 O 3 /ZrO 2 laminated films, permeation barrier properties improved as the number of alternating layers increased. Permeation barrier properties were closely related to the number of interfaces because of the ZrAl x O y phase that formed at the interface between the Al 2 O 3 and ZrO 2 sublayers. The ZrAl x O y phase was denser than single layers of Al 2 O 3 and ZrO 2 and had a homogeneous amorphous structure. The formation of a ZrAl x O y phase in Al 2 O 3 /ZrO 2 laminated film effectively improved the permeation barrier properties of the film.