| 摘要 |
PURPOSE:To obtain a cesium ion beam that can finely be stopped down by heating a heater, melting a cesium compound, and emitting a cesium ion from the small hole of a lead-out electrode. CONSTITUTION:An ion source consists of a reservoir 1, heater 2, emitter needle 3, and lead-out electrode 4. The needle 3 is protruded from a small hole 1a provided at the tip of the reservoir and the tip of the needle 3 is for a tapered pin form by electrolytic abrasion and such. A cesium compound powder 5 is packed inside of the reservoir 1 and an ion source is mounted on a secondary ion mass spectrometer and such. The reservoir 1 is vacuum exhausted, and then a heater 2 is electrified. The melted cesium compound reaches the tip of the needle 3 and is evaporated and ionized by an electric field applied between the needle 3 and the electrode 4, and a primary ion 7 is emitted from a small hole 6 provided at the electrode 4. As a result, a cesium ion beam that can finely be stopped down can be generated. |
