Stability and Performance of Organic-Inorganic Thin Films on Polymer Substrates

摘要

Polymer is replacing glass at an increasing rate in uses ranging from ophthalmic applications to electronic devices and displays. In the case of optical interference filters on plastic substrates such as antireflective coatings, the performance of the device is limited by the coating-substrate compatibility; for example, thermal expansion coefficient of the substrate is about 100 times that of glass. Significantly improved resistance to temperature and humidity variation and higher elastic recovery of organic-inorganic SiO_2 and ZrO_2 coatings compared to their inorganic counterparts are demonstrated. Organic-inorganic coatings prepared by ion-beam-assisted chemical vapor deposition (IBACVD) show a higher thermal expansion (105 K1) close to that of polymer substrates (10~(-4) K~(-1) for CR-39) as well as a relatively high hardness/elastic modulus (H/E) ratio (up to 0.16). Both individual organic-inorganic layers and complete antireflective stacks exhibit a higher durability following accelerated environmental tests including exposure to high temperature/ high humidity, ultraviolet (UV) and solar radiation, and a saline solution.