| 초록 |
Sol-gel-derived, crack-free, and condensed TiOx thin films with improved barrier properties were successfully fabricated on polymer substrates with a simple two-step heat treatment at low temperatures. To assess the barrier properties of the TiOx thin films, calcium corrosion tests were conducted and their water vapor transmission rates (WVTRs) were measured. We found that the two-step heat treatment (at 45 °C for 90 min and 110 °C for 60 min) produces a close-packed TiOx structure that substantially reduces the WVTRs of the coated polymer substrates. The WVTRs of 86 nm thick TiOx thin films on polyethylene naphthalate (PEN) substrates at a relative humidity (RH) of 90% were found to be 0.133 g m−2 day−1 at 38 °C and 0.0387 g m−2 day−1 at 25 °C. In addition, the WVTR value of the TiOx thin films on PEN substrates are stable with respect to bending: it was found to increase by only ∼13% after 100 repetitions of bending with a 20 mm radius. |
