【作者】 张子斌； 翟利华； 韦冠一； 李雪松；

【Author】 ZHANG Zi-bin, ZHAI Li-hua, WEI Guan-yi, LI Xue-song (Northwest Institute of Nuclear Technology, Xi’an 710613, China)

【机构】 西北核技术研究所；

【Abstract】 A scheme of hemispherical hot cavity solid ion source with electron impact is brought up. Sample evaporation and ionization is accomplished in the quasi-tight hemispherical cavity. The two axial designed holes are used to lead electrons into the cavity and to draw ions out of it. The area of two holes takes up only 1/150 of whole cavity’s surface area. Sample atoms after evaporation will go through many times of sticking, desorption, release and finally diffuse out of the cavity and be partly ionized. The flying direction of atoms and ions in cavity points to the cavity center. Electrons from ring cathode are focused into the cavity by electrostatic field without magnet. The hemispherical cavity was heated by axis current which forms a centripetal field to drift ions in cavity. In the area close to the cavity center, ions will be drawn out and focused to a point. The atom’s ionization efficiency, the ion’s extracting performance, the fractionation and chemistry selectivity, and the applicable scope about this ion source are discussed.更多还原