Protection of polymer from atomic-oxygen erosion using Al2O3 atomic layer deposition coatings

Abstract Thin films of Al 2 O 3 grown using atomic layer deposition (ALD) techniques can protect polymers from erosion by oxygen atoms. To quantify this protection, polyimide substrates with the same chemical repeat unit as Kapton ® were applied to quartz crystal microbalance (QCM) sensors. Al 2 O 3 ALD films with varying thicknesses were grown on the polyimide substrates. The ALD-coated polyimide materials were then exposed to a hyperthermal atomic-oxygen beam. The mass loss versus oxygen-atom exposure time was measured in situ by the QCM. Al 2 O 3 ALD film thicknesses of ∼ 35 A were found to protect the polymer from erosion.