Crystal growth from the vapor phase is an alternative to melt solidification and sintering for fabricating optical materials with high melting points and reversible phase transformations. We demonstrated the rapid synthesis of transparent thick films of Eu-doped monoclinic HfO2 (Eu3+:HfO2) and cubic Lu2O3 (Eu3+:Lu2O3) using laser-assisted metal–organic chemical vapor deposition. The transparent single-crystalline films were epitaxially grown on yttria-stabilized zirconia substrates at the deposition rates of 15–20 µm h−1. Under irradiation by ultraviolet light, the Eu3+:HfO2 and Eu3+:Lu2O3 transparent thick films exhibited intense red emissions at 614–615 nm corresponding to the 5D0 → 7F2 transitions of the Eu3+ ions located in asymmetric environments.

We demonstrate the high-speed epitaxial growth of a Eu 3+ -doped Y 2 O 3 (Eu 3+ :Y 2 O 3 ) thick film phosphor grown on a (100) yttria-stabilized zirconia substrate by laser-assisted metalorganic CVD. The deposition rate was 42 μm h −1 and the resultant 7-μm-thick Eu 3+ :Y 2 O 3 film was optically transparent. Under UV and X-ray irradiation, the Eu 3+ :Y 2 O 3 thick film emitted red light originating from the 5 D 0 → 7 F 2 transition of Eu 3+ ions with a fluorescence decay time of 1.7 ms.

We demonstrate the rapid synthesis of Ce 3+ -doped Lu 3 Al 5 O 12 (Ce 3+ :LuAG) thick film phosphor grown by laser-assisted chemical vapor deposition. The radioluminescence properties of the film are compared with those of Ce 3+ :LuAG single crystals. The (100) Ce 3+ -LuAG thick film was epitaxially grown on a (100) Y 3 Al 5 O 12 substrate at a deposition rate of 16 nm s −1 . Under UV and X-ray irradiation, the film emitted a yellow-green light originating from 5d-4f transitions of Ce 3+ ions. Under α-ray excitation from an 241 Am source, the scintillation decay curve of the Ce 3+ :LuAG thick film was fitted to two time constants, 32 and 666 ns, associated with the Ce 3+ centers and antisite defects in garnet structures, respectively.

Radiography is non-destructive imaging for engineering, medical diagnostics, airport security checks, and decontamination activities in nuclear plants. Inorganic scintillators are phosphor materials that convert radiation into visible photons with high luminescence and fast response, and scintillators with a few tens of micrometers thickness can improve sensitivity in radiation detection and imaging. To date, a production method for thick film scintillators is a time and cost consuming way of slicing and poshing bulk single crystals and transparent ceramics. Here, the chemically vapor deposited Ce3+-doped Lu3Al5O12 thick film scintillators (CVD-Ce3+:LuAG) with a thickness of 1–25 μm were produced at deposition time of 1–30 min. Numerical simulations indicated the penetration depth of α-particle in Ce3+:LuAG is 12.8 μm, and the 14-μm-thick CVD-Ce3+:LuAG showed highest light yield (31,000 photons 5.5 MeV−1), superior to the commercial Ce3+:LuAG single crystal scintillator (21,000 photons 5.5 MeV−1). In the X-ray radiograph taken with CVD-Ce3+:LuAG as a scintillation screen, 5-μm-width bar of metal microgrids can be identified. Vapor deposition technique can be a novel high-throughput production way of a thick film scintillator which is in a micrometer-thickness effective to converting radiations into photons for sensitive α-emitter detection and high-resolution X-ray imaging.

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