Densification of cerium-doped lutetium oxyorthosilicate scintillation ceramics by hot isostatic pressing

The effects of presintering temperature, soak time, and Hot Isostatic Pressing (HIPing) temperature on the microstructure and densification behavior of cerium-doped lutetium oxyorthsilicate (Lu₂SiO₅:Ce, LSO:Ce) ceramics were investigated. It was determined that the most suitable presintering conditions (minimum presintering temperature and shortest soak time) required to obtain closed porosity were a 4 h dwell at 1650 °C in air. The optimal HIPing conditions to achieve full density were determined to be 1 h at 1650 °C under a 150 MPa Ar atmosphere. The luminescence decay time of the HIPed LSO:Ce ceramics is composited of a fast component of 10 ns (51%) and a slow component of 31 ns (49%), which is shorter than that of cerium-doped rare earth oxyorthsilicate single crystal. The light yield of the LSO:Ce ceramics reaches 21,000 photons/MeV, which is ∼95% of the value of a typical LSO:Ce single crystal. - Highlights: • LSO:Ce scintillation ceramics were fabricated by HIPing at 1650 °C/150 MPa for 1 h. • The in-line transmittance of the HIPed LSO:Ce ceramics reaches 50% at 4.4 μm. • The luminescence decay time of the LSO:Ce ceramics is 10 ns (51%) and 31 ns (49%). • Light yield of the LSO:Ce ceramics reaches 95% of that of a typical LSO:Ce crystal.