| 摘要 |
PURPOSE:To simplify the structure of a monitor and to measure an intense beam by forming a metallic film on an insulating substrate and obtaining a Faraday cup. CONSTITUTION:Holes 2 are drilled in the surface of the substrate 1 made of boron nitride which is represented as an insulator having superior machinability and heat conductivity. Then copper films 3 are formed only inside the holes 2 by vacuum vapor deposition, etc. Here, when a charged particle beam enters the Faraday cup formed of the hole 2 and copper film 3, charges are generated on the copper film 3 according to the Faraday rule and a current flows to a bolt 4 and a lead wire 6. A bias plate 7 is applied with a negative voltage to suppress a secondary voltage from the Faraday cup. Thus, the Faraday cut is formed directly in the insulating substrate and then the structure is simplified; and the whole Faraday cut contacts the insulator, so heat is easily lost from the Faraday cut and the intense beam can be measured.
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