Large GSO single crystals with a diameter of 100 mm and their scintillation performance

Cerium-doped [Gd.sub.2]Si[O.sub.5] (GSO) scintillator has good scintillation properties such as high density, intense light output, short decay time, excellent temperature stability, and extremely good energy resolution. In order to apply GSO single-crystal scintillators to a commercial PET, we have tried to increase the size of the GSO single-crystal for increasing production capacity and reducing production cost. To grow the large GSO single-crystal, we have optimized growth conditions and atmosphere in the furnace. We have developed growing technology of large GSO single crystals with a diameter of 100 ram. Thousands of specimens with a size of 4 x 6 x 20 [mm.sup.3] were sampled from each ingot. Uniformity of the light output, energy resolution and decay time in the crystal has been demonstrated for PET application. Index Terms--Crystal growth, gadolinium compounds, positron emission tomography (PET), scintillation detectors.