Optical Ceramic Scintillator for PET

Phase-pure transparent LSO ceramic was obtained, with its scintillation properties rivaling those of single crystalline LSO. The transparent LSO ceramic was prepared by a nano-technology approach. The densities of the LSO ceramic increased with increasing sintering temperature. Further SEM examination confirmed the decrease of the porosity during densification of the ceramic. Pores were segregated at grain boundaries after sintering. Hot isostatic pressing (HIPing) was employed to further densify the ceramic and eliminate porosity after sintering. Transparent polycrystalline LSO ceramics were obtained after the final HIP. XRD examination confirms single monoclinic LSO phase. A light output as high as 30,100 ph/MeV was obtained using a 22 Na excitation source. LSO ceramic showed an energy resolution of 15% (FWHM) at 662 keV ( 137 Cs source) and a fast scintillation decay of 40 ns due to the 5d \ura 4f transition of Ce 3+ . The excellent scintillation and optical properties make LSO ceramic a promising candidate for future gamma-ray spectroscopy as well as medical imaging applications.