Jin Q Y, Zhou Y, Sun L T, Liu Y G, Zhang X Z, Zhao H W
Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Rev Sci Instrum. 2019 Nov 1;90(11):113317. doi: 10.1063/1.5128526.
A negative oxygen ion source is under development to produce O and O beams used for a secondary ion mass spectrometer at Institute of Modern Physics (IMP), and both filament and radio frequency (RF) schemes are tested. The filament driven ion source, which was initially designed for H production, has a 10-pole multicusp plasma chamber, two sets of virtual magnetic filters, and a 3-electrode extraction system. The RF scheme, which is improved by changing a RF back plate from the filament ion source, has an external planar spiral RF antenna behind an AlN window. The RF power system consists of a continuous wave (CW) 13.56 MHz/2 kW power supply, a capacitive automatching network and a water-cooled flat RF antenna made from a 6-mm copper tube. Oxygen and carbon dioxide gases are used to produce O and O ion beams, and ion composition is analyzed by using a Wien filter. However, the lifetime of filaments sustains from several minutes to hours before fracture occurred while the RF one can work stably with no maintenance, and the experiment results will be given on O ion production with two different technologies using our ion source test facility.
现代物理研究所正在研发一种负离子源，用于产生用于二次离子质谱仪的O和O束，目前正在对灯丝和射频（RF）方案进行测试。最初设计用于产生H的灯丝驱动离子源，有一个10极多尖峰等离子体腔、两组虚拟磁过滤器和一个三电极提取系统。射频方案是通过改变灯丝离子源的射频背板改进而来，在AlN窗口后面有一个外部平面螺旋射频天线。射频电源系统由一个连续波（CW）13.56 MHz/2 kW电源、一个电容式自动匹配网络和一个由6毫米铜管制成的水冷扁平射频天线组成。使用氧气和二氧化碳气体产生O和O离子束，并使用维恩过滤器分析离子组成。然而，灯丝的寿命在断裂前只能维持几分钟到几小时，而射频离子源可以无维护稳定工作，将给出使用我们的离子源测试设施采用两种不同技术产生O离子的实验结果。
