A flexible moisture barrier comprised of a SiO_2-embedded organic-inorganic hybrid nanocomposite and Al_2O_3 for thin-film encapsulation of OLEDs

摘要

We demonstrated a high performance flexible multi-barrier containing a silica nanoparticle-embedded organic-inorganic hybrid (S-H) nanocomposite and Al_2O_3. The multi-barrier was prepared by low-temperature Al_2O_3 atomic layer deposition and with a spin-coated S-H nanocomposite. The moisture barrier properties were investigated with a water vapor transmission rate (WVTR), estimated by a Ca test at 30 ℃, 90% R.H.. Moisture diffusion was effectively suppressed by the sub-700 nm thick multi-barrier incorporating well-dispersed silica nanoparticles in the organic layer. A low WVTR of 1.14 × 10~(-5) g/m~2 day and average transmittance of 85.8% in the visible region were obtained for the multi-barrier. After bending under tensile stress mode, the moisture barrier property of the multi-barriers was retained. The multi-barrier was successfully applied to thin-film encapsulation of OLEDs. The thin-film encapsulated OLEDs showed practicable current-voltage-luminance (I-V-L) characteristics and stable real operation over 700 h under ambient conditions.