Volume 2 Supplement 1
First results with SiPM tiles for TOF PET based on FBK RGB-HD technology
© Ferri et al; licensee Springer. 2015
Published: 18 May 2015
We present the first results of timing and energy resolution of two newly developed tiles based on FBK RGB-HD SiPMs. The first tile has dimensions of 32x32 mm2 and is composed of 8x8 SiPMs, with a regular pitch of 4 mm and a cell size of 25x25 μm2. Although manufactured with a standard bond wire technology, the tile achieves a fill factor at the tile level of 85%. We produced two versions: one with a single-ended and the other with differential readout. We tested the first prototypes with single-ended readout with a scintillator array, perfectly matching the tile pitch and composed of 8x8 LYSO crystals with dimensions of 4x4x22 mm3. First, we tested the tile using a single-channel setup, based on a fast, discrete amplifier, a digital oscilloscope and a PC, reading one SiPM at a time. At 20 °C, we measured an energy resolution of 10.7% FWHM. For the timing measurements we compared two conditions: when only one SiPM was biased and read, and when all the 64 SiPMs were biased but only one was read. At 20 °C, we measured a timing resolution of 200 ps FWHM in the first case, and 220 ps FWHM in the second case. Then, we tested the whole tile with a dedicated ASIC (PETA3), and measured the energy and timing resolution of two tiles in coincidence. The second tile is composed of 144 SiPMs, mounted on a water cooled, ceramic LTCC substrate. On the top side, it contains 12x12 SiPMs with a regular pitch of 2.5 mm. Also in this case, the SiPM technology is the RGB-HD with a cell size of 25x25 μm2. On the bottom side, four readout ASICs of the latest generation (PETA5) are flip-chip mounted. First results will be presented.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.