Development of an Accelerator Mass Spectrometry Facility forTrace Impurity Characterization of Electronic Materials

目前有必要表征微量元素， 电子材料中的杂质含量低于十亿分之一。 这个奖项是为了开发这样一种工具， 电子材料稳定微量元素分析 加速器质谱（AMS）。虽然AMS已应用于 涉及具有极高灵敏度的放射性同位素测定， 现有的AMS仪器不是为稳定元素设计的 分析和不能充分执行这些测量 而无需进行大量修改。我们提出了一个文书， 一种超低样品污染的超高真空溅射离子源， 注入质量分析负二次离子， 将样品放入3 MV串列加速器中。在串联期间 加速时，电子从离子中剥离;对于电荷， 大于2+的状态，只有原子离子存活。动量/电荷 和能量/电荷鉴别，然后是速度和总 能量检测，提供明确的元素识别 灵敏度为万亿分之一拟议 仪器将提供超灵敏痕量分析 该技术适用于各种样品。

There is a present need to characterize trace elements in electronic materials at impurity levels of sub parts-per-billion. This award is for the development of such an instrument for stable trace element analysis of electronic materials using Accelerator Mass Spectrometry (AMS). While AMS has been applied to radioisotope determinations with extremely high sensitivities, existing AMS instruments are not designed for stable element analysis and can not adequately perform these measurements without extensive modifications. We propose an instrument with an ultra-low sample-contamination UHV sputter ion source which injects mass-analyzed negative secondary ions from the sample into a 3 MV tandem accelerator. During tandem acceleration, electrons are stripped from the ions; for charge states greater than 2+, only atomic ions survive. Momentum/charge and energy/charge discrimination, followed by velocity and total energy detection, provide unambiguous elemental identification with a sensitivity of 1 part-per-trillion. The proposed instrument will provide a super-sensitive trace analysis technique which is applicable to a large variety of samples.