As part of the Next Generation Neutron Detector project, which is funded by the National Science Foundation through a collaborative major research instrumentation grant, MoNA students and researchers are busy building prototype detectors. The prototype detectors are being used to collect data that will help us to optimize the final detector design. This detector is based on Silicon Photomultipliers (SiPM). In order to allow for different detector configurations, the prototype is highly modular and designed to connect to interlocking plastic bricks (LEGO). So we can call these detector bricks! With this we can very quickly test different detector configurations.
But before the prototypes can be tested, they need to be built. For the design we use an integrated cad software (Fusion 360) that allows us to do the printed circuit board (PCB) design and the mechanical design. Students learned to use this software and created design variations that lets us test different types of SiPMs.
Once the PCBs and electronics components arrive, the detector bricks need to be assembled. The SiPM chips are between 3 mm by 3 mm and 6 mm by 6 mm, and have a Ball Grid Array, tiny solder dots that are hidden under the chip, to be mounted onto the PCB. This requires some very precise work in order to apply the solder paste with a stencil and to position the SiPM. After this the detector bricks a placed in a reflow oven for soldering.
So far we have assembled over 150 detector bricks, with a large fraction built by undergraduate students! Testing and evaluating of different detector configurations is under way at the participating schools.