Growth and Scintillation Properties of φ100 mm Ca:Ce:LYSO Crystal

Abstract

Abstract: In order to satisfy the requirement of the time-of-flight positron emission tomography (TOF-PET), the Ce:LYSO scintillator should have higher light output, shorter decay time and faster rise time. The transparent and inclusions-free Ca:Ce:LYSO scintillation crystal with size of φ100 mm×100 mm was successfully grown by frequency induction Czochralski method. The transmittance of the prepared crystal tested by UV-Vis spectrophotometer is close to the theoretical value, indicating its excellent quality. After cutting, grinding and polishing, the pulse height spectrum and decay time of the Ca:Ce:LYSO scintillation crystal were tested respectively. The measured light output, energy resolution and decay time are 33 962 ph/MeV, 8.6%, 36.70 ns, respectively,which shows its superior scintillation properties than Ce:LYSO. The inhomogeneity of relative light output and energy resolution of axial sampling are ±2.4% and ±9.4%, and those of the tail-radial sampling are ±1.18% and ±6.8% respectively, which proves the crystal has good uniformity.

Key words: Ca:Ce:LYSO, scintillation crystal, Czochralski method, crystal growth, scintillation property, inhomogeneity

CLC Number:

O734

WANG Jia, CEN Wei, DING Yuchong, WANG Qiang, ZHANG Zetao. Growth and Scintillation Properties of φ100 mm Ca:Ce:LYSO Crystal[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2021, 50(10): 1946-1950.

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