Improved luminescence properties of pulsed laser deposited Eu:Y₂O₃thin films on diamond coated silicon substrates

Europium activated yttrium oxide (Eu:Y₂O₃) phosphor films have been grown in situ on (100) bare and diamond-coated silicon substrates using a pulsed laser deposition technique. Diamond-coated silicon substrates were prepared using hot filament chemical vapor deposition of diamond onto silicon. Photoluminescence brightness from Eu:Y₂O₃ films grown at 700°C on diamond-coated silicon substrates was about twice that of films on bare silicon, and reached 80% of the brightness of powders. The higher brightness from Eu:Y₂O₃ film on diamond-coated silicon substrates is attributed to reduced internal reflections from the Eu:Y₂O₃ film surface, which results from the roughness of the diamond layer.