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A long-standing limitation of semiconductor neutron detectors is the lack of a scalable solution to make large area instruments. Neutron detectors are used in a wide range of applications, including the nuclear industry, safeguarding radioactive material, neutron imaging, non-destructive testing, understanding space weather effects on commercial electronics used in aviation, and for fundamental science such as nuclear and particle physics. Here we demonstrate that a solution processed organic semiconductor technology, which is scalable, can solve this aproblem. We have demonstrated detection of fast neutrons from monoenergetic beams (energies 0.565 and 16.5 MeV), from AmBe sources, and thermal energy (0.025 eV) in devices sensitised with B-10 enriched B_4C. This energy range is of interest for many of the applications listed above. The detector response is found to be linear with flux up to 1.5 x 10^7 n/cm^2/s. As organic semiconductors are a similar density to human tissue, this technology may be of interest for medical physics applications, for example B neutron capture therapy dose monitoring and understanding neutron interactions in human tissue., Comment: 21 pages, 15 figures including supplementary information; 9 pages, 4 figures excluding SI

We report on the energy, timing, and pulse-shape discrimination performance of cylindrical 5 cm diameter x 5 cm thick and 7 cm diameter x 7 cm thick {\it trans}-stilbene crystals read out with the passively summed output of three different commercial silicon photo-multiplier arrays. Our results indicate that using the summed output of an 8x8 array of SiPMs provides performance competitive with photo-multiplier tubes for many neutron imaging and correlated particle measurements: for the 5x5 cm crystal read out with SensL's ArrayJ-60035\_64P-PCB, which had the best overall properties, we measure the energy resolution as 13.6$\pm$1.8\% at 341 keVee, the timing resolution in the 100--400 keVee range as 277$\pm$34 ps, and the pulse-shape discrimination figure-of-merit as 2.21$\pm$0.03 in the 230--260 keVee energy range. These results enable many scintillator-based instruments to enjoy the size, robustness, and power benefits of silicon photo-multiplier arrays as replacement for the photo-multiplier tubes that are predominantly used today.