| 초록 |
We prepared nanostructured polymer thin film on GaN-based UV-LEDS and investigated the effect on light extraction in UV-light region. Employing UV-curable polymer, gradually nanostructured polymer films were successfully fabricated on UV-LEDs by curing the pre-deposited first layer and imprinting the second uncured layer with the nanopatterned soft mold. Controlling the thickness of the first layer in between 21 nm and 120 nm, we studied how the thickness of continuous layer could affect on photoluminescence of GaN-based UV-LEDs. We found that light extraction increased 25 % average in UV region for the nanopatterned polymer top layers, but we did not observe the significant effect of the thickness of continuous first layer. On the other hand, it was meaningful that we experimentally proved that residual layer possibly existing in nanopatterning process did not affect on light extraction less than one hundred nanometer in thickness. |
