Abstract
A multi-layer a-Si:H based thermal neutron detector was designed, fabricated and simulated by Monte Carlo method. The detector consists of two a-Si:H pin detectors prepared by plasma enhancd chemical vapor deposition (PECVD) and interfaced with coated layers of Gd, as a thermal neutron converter. Simulation results indicate that a detector consisting of 2 Gd films with thicknesses of 2 and 4 µm, sandwiched properly with two layers of sufficiently thick (~30µm) amorphous silicon diodes, has the optimum parameters. The detectors have an intrinsic efficiency of about 42% at a threshold setting of 7000 electrons, with an expected average signal size of ~12000 electrons which is well above the noise. This efficiency will be further increased to nearly 63%, if we use Gd with 50% enrichment in 157Gd, We can fabricate position sensitive detectors with spatial resolution of 300 µm with gamma sensitivity of ~1x10-5. These detectors are highly radiation resistant and are good candidates for use in various application, where high efficiency, high resolution, gamma insensitive position sensitive neutron detectors are needed.
Original language | English |
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Pages (from-to) | 915-921 |
Number of pages | 7 |
Journal | IEEE Transactions on Nuclear Science |
Volume | 41 |
Issue number | 4 |
DOIs | |
State | Published - Aug 1994 |