The variation of the enhanced PL efficiency of Y2O3:Eu3+ phosphor films with the height to the ZrO2 nanoparticle-assisted 2D PCL by reverse nano-imprint lithography

Abstract

We developed a zirconium oxide (ZrO2) nanoparticle-assisted photonic structure for improving the light extraction efficiency of Y2O3:Eu3+ phosphor films by reverse nano-imprint lithography approach. The structural effect of a two-dimensional (2D) ZrO2 nanoparticle photonic crystal (PC) pattern on the extraction efficiency of photoluminescence (PL) from the underlying Y2O3:Eu3+ phosphor film was investigated. The 2D photonic crystal structure was fabricated using a reverse nano-imprint process with a ZrO2 nanoparticle solution as a nano-imprint resin and a patterned trimethylolpropane propoxylate triacrylate (TPT)/polydimethylsiloxane (PDMS) stamp as a mold. We controlled height of ZrO2 nanoparticle patterns in the range 190-370 nm by varying the height of master mold. This simple process results in 6.9 times improvement of extraction efficiency for a 2D ZrO2 nanoparticle-assisted photonic crystal pattern (h = similar to 370 nm) compared to the conventional Y2O3:Eu3+ thin-film phosphors.