高分辨二次离子质谱超高真空样品台的研制

目前，微束类分析仪器的一次离子束斑越来越精细，直径已达到微米级甚至亚微米级，仪器真空度也已达到稳定的超高真空水平，因此，亟需研制一种与之相匹配的高分辨样品台，提高在超高真空环境下的分辨力及定位精度。新研制的样品台，通过置于真空腔体外部的高精度滑台驱动小型焊接波纹管的伸缩传递三维运动，解决了大尺寸焊接波纹管表面放气及承受较大大气压力的问题；通过使用适用于超高真空的材料和固体润滑、无动态密封，解决了高真空中摩擦偶件的润滑问题。实验数据表明：在40 mm行程范围内，运动平台三轴定位重复性为0.94、1.83、0.38 μm，分辨力为0.10 μm，并已成功地应用在1.19×10^-6 Pa超真空环境下。外置的高精度滑台不仅克服了真空电机在真空腔体内发热及绝缘材料放气的问题，而且不需要引入任何电子电气元件及导线，不会在分析腔室内产生电磁干扰，行程不受装置本身的限制。这些特性不仅可满足二次离子质谱仪的要求，也适用于具有高分辨、超高真空环境、无污染要求的其他分析测试仪器。

Innovative High Resolution 3D Sample Stage in Ultra High Vacuum for SIMS

Primary ion beam spot of microbeam analysis instrument is more and more fine, and its diameter has reached micron level and even sub micron level. Instrument vacuums have advanced to ultra-high levels, and which have excellent stability. Therefore, it is urgent to develop a kind of high resolution sample stage. An innovative 3D sample stage in a new TOF-SIMS instrument was developed aiming at the defects of commercial instrument, which purpose is to achieve precise, reproducible, sample positioning in an ultra-high vacuum environment. Through high precision sliding table arranged in the vacuum cavity external driving small welded bellows telescopic, 3D motion was transferred. Externally mounted motors eliminated out-gassing, while the use of small bellow-sealed drives avoided the stresses associated with large diameter bellows. Only UHV-compatible materials and dry lubricants was used, in order to solve the lubrication problem of friction parts in high vacuum environment. A reproducibility of 0.94, 1.83, 0.38 μm for 40 mm moving range and minimum step length 0.1 μm on all axes in a vacuum of 1.19×10^-6 Pa were achieved. Newly designed externally mounted motor overcame insulating material outgassing problems within the vacuum chamber. In addition, it does not introduce any additional electronic components and wiring, thus will not cause electro-magnetic interferences within the analyzer chamber, and its travelling rang will not be restricted. These special functions are suited not only for SIMS, but also for many other high-resolution analytical instruments that require ultra-high vacuum and ultra-clean (contamination-free) environments.