title: Characterization of silicon photomultipliers at National Nano-Fab Center for PET-MR.
abstract: The silicon photomultipliers (SiPMs) were fabricated for magnetic resonance compatible positron emission tomography (PET) applications using customized CMOS processes at National NanoFab Center. Each micro-cell consists of a shallow n+/p well junction on a p-type epitaxial wafer and passive quenching circuit was applied. The size of the SiPM is 3 × 3 mm(2) and the pitch of each micro-cell is 65 μm. In this work, several thousands of SiPMs were packaged and tested to build a PET ring detector which has a 60 mm axial and 390 mm radial field of view. I-V characteristics of the SiPMs are shown good uniformity and breakdown voltage is around 20 V. The photon detection efficiency was measured via photon counting method and the maximum value was recorded as 16% at 470 nm. The gamma ray spectrum of a Ge-68 isotope showed nearly 10% energy resolution at 511 keV with a 3 × 3 × 20 mm(3) LYSO crystal.
authors.affiliation: Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea.
authors.forename: Hyoungtaek
authors.initials: H
authors.lastname: Kim
authors.affiliation: National NanoFab Center, Daejeon 305-701, South Korea.
authors.forename: Woo Suk
authors.initials: WS
authors.lastname: Sul
authors.affiliation: Department of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea.
authors.forename: Gyuseong
authors.initials: G
authors.lastname: Cho