Growth and Characterization of Eu :  Y 2 O 3 Thin‐Film Phosphors on Silicon and Diamond‐Coated Silicon Substrates

Abstract

Europium-activated yttrium oxide (Eu:Y203) phosphor films have been grown in situ on (100) bare silicon and diamond-coated silicon substrates using a pulsed laser deposition technique. Diamond-coated silicon substrates were prepared by hot filament chemical vapor deposition onto (100) silicon wafers. Measurements of photoluminescence and cathodoluminescence properties of Eu:Y203 films have shown that the films grown on diamond-coated silicon substrates are brighter than the films grown on bare silicon substrates under identical deposition conditions. The improved brightness of the Eu:Y202 films on diamond-coated silicon substrates is attributed to reduced internal reflection, low photon energy absorption by substrate, and enhanced scattering of incident beam with lattice. All these effects are primarily brought about by the presence of a rough diamond interfacial layer between the phosphor films and substrates.

Enhanced luminescence from spontaneously ordered Gd2O3:Eu3+ based nanostructures

“…9 the brightness of Li + doped Gd 2 O 3 :Eu 3+ films annealed at 973 K were increased by a factor of 3.04 in comparison with that of Gd 2 O 3 :Eu 3+ films annealed at same temperature and 1.18 times increased in comparison with undoped Gd 2 O 3 :Eu 3+ films annealed at 1173 K. In comparison with Li + doped and undoped films annealed at 973 K, the improvement in PL brightness with the Li + doping may be attributed to the following reasons. The crystallinity become improved and the crystalline size become twice, the improved crystallinity leading to higher oscillating strength for optical transitions [59] and the increased crystalline size reduces the grain boundary density which may act as sources of dissipation, adsorbing and/or scattering light generated inside the film that resulted in lower PL brightness. The increased surface roughness with Li + doping may reduce the loss of emitted light due to internal reflections within the film.…”

Photoluminescence Properties of Nanocrystalline Diamond Grown By MPECVD in CH4/H2/N2 Ambient

“…CVD diamond-based phosphors have emerged as potential candidates in display technology primarily because the large diamond bandgap (5.5 eV) (1) enables transparency at very high temperatures and radiation intensities by preventing heat generated charge carriers. Cho et al suggests that thin-film phosphors have several advantages over powder phosphors, namely higher lateral resolution with smaller grains, better thermal stability, reduced outgassing, better matched surface adhesion to substrates, and a more uniform surface morphology (2). The motivation for this research is the possibility of using diamond as a photonic substrate, a semiconductor via doping, or both together on a single chip, requiring an understanding of the trade-offs between purity and performance for obtaining a conductive material that maintains transmissive properties.…”