ABSTRACT
Plasma polymers [materials formed by luminous chemical vapor deposition (LCVD)] have their unique advantage in ultrathin film applications (e.g., less than 100 nm), due to their chemical inertness, good adhesion to nearly any substrate, and excellent barrier properties. However, these advantageous characteristics are specific to type A plasma polymer, and when their thickness grows beyond a threshold value (e.g., several micrometers), plasma polymer films tend to crack or buckle from a rigid substrate due to the internal stress in the film, which develops during the deposition process. When either cracking or buckling occurs, plasma polymer films will lose their excellent protective properties. Therefore, the consideration of the internal stress is crucially important for achieving plasma polymer protective coatings because the thicker is not the better.
