CAREER: Evaluating Molecular Homogeneity in Three Nanometric Dimensions Using Nano-Projectile Secondary Ion Mass Spectrometry

在化学系化学测量和成像项目的支持下，加州州立大学北岭分校（CSUN）的Michael埃勒和他的学生将致力于开发新的分析方法，用于在接近5纳米的尺度上进行3D分子分析。这项研究预计将产生新的仪器，旨在提供对半导体器件生产中使用的薄膜分子组织的见解。这些见解可能会导致新的材料设计，确保继续朝着更高性能的计算设备发展。埃勒博士还将建立新的招聘和推广计划，以促进在科学，技术，工程和数学（STEM）的代表性不足的少数民族的参与，并为学生提供机会，互动和网络与化学家在工业工作。加州州立大学北岭分校的埃勒小组将设计和验证实验方法，跟踪分子协会在三维纳米空间。将追求两个互补的目标;（i）阐明分子组织横向上的规模接近5纳米，（ii）也垂直5纳米的深度。该分析方法是基于二次离子质谱（西姆斯）的一种变体，称为纳米粒子西姆斯，其中不是使用聚焦离子束，而是使用一套（10^6 - 10^7）在空间和时间上分离的纳米粒子随机分析表面。这些射弹中的每一个都采样纳体积（直径约10 nm），并且收集电离的喷出物，进行质量分析，并存储为单独的质谱。所提出的研究的总体假设是，分析物特定的二次离子携带与其原始分子组织相关的信息。通过空间分辨探测记录共同发射的二次离子的轴向和径向能量，将在低于撞击坑大小的尺度上提供关于其横向组织的信息。 将这种新的能力与低能氩团簇深度分析相结合，将能够分析三个纳米尺寸的分子均匀性。这种新的仪器将允许在西姆斯过程中的基本机制的发现，并提供在半导体器件的生产中使用的薄膜的均匀性的增强的洞察力。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Michael Eller and his students at California State University Northridge (CSUN) will work on developing new analytical approaches for performing 3D molecular analysis at scales approaching five nanometers. The research is expected to result in new instrumentation that is being designed to provide insights into the molecular organization of thin films used in the production of semiconductor devices. These insights may lead to new material designs, ensuring continued progress towards higher performing computational devices. Dr. Eller will also establish new recruitment and outreach programs to promote participation of underrepresented minorities in science, technology, engineering and mathematics (STEM )and provide opportunities for students to interact and network with chemists working in industry.The Eller group at Cal-State-Northridge will devise and validate an experimental methodology that tracks molecular associations in 3D nanometric space. Two complementary objectives will be pursued; (i) elucidating molecular organization laterally on a scale approaching 5 nm and (ii) also vertically 5 nm in depth. The analytical approach is based on a variant of secondary ion mass spectrometry (SIMS) termed nanoprojectile SIMS, where instead of using a focused ion beam, a surface is analyzed stochastically with a suite (10^6 – 10^7) of nanoprojectiles separated in space in time. Each of these projectiles samples a nanovolume (~10 nm in diameter) and the ionized ejecta are collected, mass analyzed, and stored as an individual mass spectrum. The overall hypothesis of the proposed research is that analyte-specific secondary ions carry information related to their original molecular organization. Recording the axial and radial energies of co-emitted secondary ions via spatially resolved detection will provide information on their lateral organization at a scale below the size of the impact crater. Combining this new capability with low energy argon cluster depth profiling will enable analysis of the molecular homogeneity in three nanometric dimensions. This new instrumentation will allow for the discovery of fundamental mechanisms in the SIMS process and provide enhanced insights into the uniformity of thin films used in the production of semiconductor devices.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.