GB761404A - Improved methods of and means for converting the energy of nuclear radiations into useful electrical energy - Google Patents

Abstract

761,404. Semi-conductor devices. RADIO CORPORATION OF AMERICA. June 10, 1954 [June 30, 1953], No. 17130/54. Class 37. [Also in Group XL (a)] An electrical device comprises a semiconductor body having a potential barrier region which is irradiated by emissions from a nuclear source to provide a potential between output contacts on either side of the barrier. In the examples described, a PN junction in a germanium or silicon body is irradiated by nuclear emission, which produces electron-hole pairs in the material; the carriers produced in the neighbourhood of the junction flow across the potential barrier existing thereat to make the P region positive relative to the N region, so that a current is produced in an external circuit. Carriers produced adjacent the junction region may flow to the region by diffusion and thus contribute to the current. In Fig. 1, emission from nuclear source 11 penetrates the semi-conductor body 13 comprising a PN junction 15, to produce current in load 21. In Fig. 4, several semi-conductor bodies are positioned so that emission from source 11 is normal to the PN junctions and penetrates them sequentially until absorption is complete. The outputs are connected in parallel or the bodies may be arranged to contact each other to provide a series output, Alloy-diffusion junction, or grown PN junction, or point contact devices may be used. Fig. 9 shows four series arrangements connected in parallel, surrounding the source 11 of nuclear emission, which is insulated from the semiconductor bodies by insulating layers 39. The junctions 41 and 43, which would tend to provide a potential in opposition to that of the remaining junctions, are effectively destroyed by sandblasting or copper plating. The nuclear source may be coated on or placed in contact with one of the semi-conductor regions and used as an electrode. In an alternative arrangement, the P and N regions are in the form of concentric hollow cylinders surrounding the nuclear source. The device may be used to energize transistors. The nuclear source may emit charged or neutral particles, and may consist of polonium, uranium (for α particles), strontium 90, tritium (for # particles) or cobalt 60 (for y rays).