YAG:Ce Scintillators

1Overview

YAG:Ce is a Ce-doped Yttrium Aluminum Garnet (Y₃Al₅O₁₂) oxide crystal. It belongs to the garnet structural family and grows without any hygroscopic character, which is a significant advantage in open-lab and field environments where NaI(Tl) or LaBr₃(Ce) would require hermetic enclosure. The crystal is mechanically hard and chemically inert, tolerating machining to tight tolerances and surviving harsh environments that would degrade halide-based materials.

The defining emission band sits at 500 to 700 nm, peaking at 550 nm. That green emission couples well to standard bialkali photomultiplier tubes and to many silicon photodiodes. The 70 ns average decay time is fast relative to NaI(Tl) (230 ns) and is useful in moderate-rate counting applications. Light yield is approximately 30,000 photons per MeV, placing YAG:Ce below the brightest halide scintillators but well above BGO and comparable fast materials.

The standout property is radiation hardness combined with non-hygroscopic stability. YAG:Ce crystal screens retain performance under prolonged electron-beam bombardment, which is the reason they became the standard fluorescent screen material in scanning electron microscopes, transmission electron microscopes, and beam-profile monitors.

2Specifications

3Optical Properties

The Ce³⁺ dopant in YAG produces a characteristic broad luminescence band peaking at 550 nm via the 5d-to-4f Ce transition. This long-wavelength emission is well above the UV cutoff of most optical windows and glass light guides, making YAG:Ce compatible with standard PMT cathodes and virtually all silicon photodetectors. The 1.83 refractive index at the emission maximum is intermediate, allowing efficient light extraction with conventional optical coupling compounds.

The material's wide transmission range (500 to 1000 nm) means it is also compatible with near-infrared readout options where a standard bialkali PMT would be insensitive. Afterglow is exceptionally low at less than 0.005 % remaining at 6 ms, which minimizes image persistence in beam-profiling applications where rapid frame-to-frame contrast is required.

Refractive index coupling and thin-screen preparation are the main variables that affect light collection efficiency in electron-microscopy applications. Polished thin discs (verify thickness availability) are the most common form factor for EM fluorescent screens.

4Typical Applications

YAG:Ce is selected when mechanical robustness, chemical stability, and radiation hardness matter more than ultimate light yield or energy resolution. Primary use cases include:

• Electron microscopy screens (SEM, TEM, FIB): fluorescent conversion screens for e-beam-to-optical conversion, replacing older powder phosphors with a single-crystal, machinable, non-outgassing alternative.
• Charged-particle beam imaging: beam-profile monitors and position detectors in accelerator beam lines and ion-implantation systems where prolonged particle bombardment would degrade halide crystals.
• X-ray imaging and scintillator screens: thin-crystal fluorescent screens for X-ray detectors and microscopy, particularly where green CCD or CMOS sensors benefit from the 550 nm emission.
• Synchrotron and lab X-ray sources: sample environment monitors and beam diagnostics where a robust, non-hygroscopic screen is required adjacent to sample chambers.
• Positron lifetime spectroscopy: the 70 ns decay is fast enough for moderate-coincidence positron annihilation work (verify with application engineering for specific time-resolution requirements).
• Fast-neutron and heavy-ion detection: research applications where radiation hardness is a primary selection criterion.
• Industrial and process imaging: environments with humidity, handling stress, or chemical exposure that preclude hygroscopic scintillator materials.

5Available Configurations

Berkeley Nucleonics supplies YAG:Ce as finished scintillator crystals and as assembled detector modules. Standard configurations below; contact BNC for custom geometries and production quantities.

Crystal Forms

Readout Options

Housing and Packaging

YAG:Ce does not require hermetic sealing. Crystals are typically supplied bare-polished, optically coupled to a window or fiber-optic plate, or mounted in an aluminum housing with optical coupling compound. All configurations are available with or without reflective wrapping. Specify thin-screen (EM), standard detector, or imaging-module configuration when requesting a quote.

6Request a Quote

YAG:Ce crystals are available in standard and custom configurations. Berkeley Nucleonics ScintIQ application engineers can advise on crystal thickness, surface finish, readout selection, and integration for electron-microscopy or beam-imaging applications. Contact us to discuss your requirements or request a sample.