| 摘要 |
A neutron detector is formed from a layer of polycrystalline diamond (12, 24, 40) which is deposited by a chemical vapour deposition process. The diamond material contains <1><0>B as a dopant, in a concentration of 1 000 ppm or less. In one embodiment, the layer of diamond material is deposited on a supporting substrate (10). Advantageously, the substrate itself may comprise a layer of diamond material. In another embodiment, the substrate comprises a layer of conductive or semiconductive material (22). The diamond material is deposited on top of the substrate, with at least two regions in contact with the semiconductive material. A central portion of the semiconductive material is etched away, and electrical contacts (26, 28) are applied to the remaining portions (22.1, 22.2) of the semiconductive substrate. An advantage of the neutron detector of the invention is that the diamond layer is very thin, less than 50 mu m thick, so that the sensitivity of the detector to other radiation, particularly gamma radiation, is reduced. <IMAGE> |
