ATOMIC LAYER DEPOSITED THIN BARRIER FILMS FOR PACKAGING

Atomic layer deposition (ALD) is a surface controlled layer-by-layer process based on self-limiting gas-solid reactions. Thin films are prepared using volatile precursors in repeating cycles until a preferred thickness is obtained. ALD suites for producing dense and pinhole-free inorganic films uniform in thickness. The most important commercial application area today is in microelectronics. The purpose of this paper is to demonstrate the potential and the challenges of using ALD for packaging materials. ALD can have a profound effect on the barrier properties and it can also be used to create antimicrobial thin films. Due to the brittle nature of inorganic thin films, these have to be protected with a polymer layer, also providing heat sealing properties. Although ALD is today carried out primarily in batch mode, the ongoing development of roll-to-roll processes will enhance the techno-economic feasibility of ALD, among others, for packaging materials.