NSF-BSF: Computation-Guided Advanced Fabrication of Silicide Nanostructures with Novel Magnetic Properties

这笔赠款支持美国和以色列的合作研究，这些研究有助于获得与制造硅技术兼容的纳米磁体相关的新知识，这对基础科学、国家繁荣和国家安全非常重要。自旋电子学需要与硅技术兼容的纳米磁铁，它可以实现对下一代纳米和微电子设备至关重要的低功率、高密度数据存储和处理。这影响了商业和国防工业中的各种技术应用。采用自下而上的方法，在硅衬底上控制纳米岛的自组装，制备过渡金属硅化物纳米结构。系统地研究了工艺-结构-性能之间的关系，以调整纳米硅化物的磁性。该项目产生的基础知识有助于发现和开发用于未来硅基技术的新型磁性纳米材料。此外，磁性过渡金属硅化物为稀土磁体提供了新的替代品，以缓解稀土元素对国家安全和环境的威胁。此外，自下而上的制造有可能扩大到与当前工业硅半导体工艺兼容的成本效益高的大批量生产。该项目涉及四名首席研究人员，他们在计算和实验方面具有互补的专业知识。它建立了美国和以色列研究人员在先进纳米制造和纳米磁学领域的合作，帮助两国更广泛的研究和教育界建立联系，并对妇女和代表性不足的少数群体参与研究产生积极影响。该项目将计算与实验无缝结合。计算研究包括第一性原理密度泛函理论计算和以原子自旋模型模拟为桥梁的微磁模拟。实验研究包括受控材料合成、在硅衬底上自组装外延硅化物纳米岛的生长、原位/非原位结构和成分表征以及磁性测量。用这种多尺度综合方法研究了硅衬底上的自组装纳米硅化物，这些纳米硅化物是通过外延沉积和热处理元素铁和钴以及它们的商业磁性合金，如坡莫合金(NiFe)和Permendur(FeCo)而产生的。本研究的目的是探索纳米硅化物中新的磁性现象，了解硅化物纳米岛的结构、形貌和空间排列对磁性的依赖机理，确定最佳结构，并通过计算指导的纳米材料加工来实现它们。该项目通过设计在下一代硅基自旋电子学和其他纳米设备中的潜在应用，为开发新的纳米磁体提供了见解。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This grant supports US-Israel collaborative research that contributes to new knowledge related to the manufacturing of silicon technology compatible nanomagnets, which is important for basic science, national prosperity and national security. Silicon technology compatible nanomagnets are needed for spintronics, which enable low-power, high-density data storage and processing critical for next-generation nano- and micro-electronic devices. This impacts a wide variety of technological applications in commercial and defense industries. A bottom-up approach based on controlled self-assembly of nanoislands on a silicon substrate is used to fabricate transition metal silicide nanostructures. The processing-structure-property relationships are systematically investigated to tailor the magnetic properties of the nanosilicides. The fundamental knowledge generated by the project contributes to the discovery and development of novel magnetic nanomaterials for future silicon-based technology. Further, the magnetic transition metal silicides provide new alternatives to rare earth magnets to ease national security and environmental threat posed by rare earth elements. In addition, bottom-up fabrication has the potential for scale-up to cost-effective high-throughput mass production that is compatible with current industrial silicon semiconductor processes. The project involves four principal investigators with complementary expertise in computation and experiment. It establishes collaboration in the areas of advanced nanofabrication and nanomagnetism between US and Israeli researchers, helps connect broader research and education communities from the two countries and positively impacts the participation of women and underrepresented minority groups in research. The project seamlessly integrates computation with experiment. Computation research involves first-principles density functional theory calculations and micromagnetic simulations bridged by atomistic spin model simulations. Experimental research involves controlled material synthesis, growth of self-assembled epitaxial silicide nanoislands on a silicon substrate, in-situ/ex-situ structural and compositional characterization and magnetic property measurement. This integrated multiscale approach is used to study self-assembled nanosilicides on Si substrates produced by epitaxial deposition and heat treatment of elemental iron and cobalt as well as their commercially available magnetic alloys, such as Permalloy (NiFe) and Permendur (FeCo). The research aims to explore new magnetic phenomena in nanosilicides, understand the mechanisms for the dependence of magnetic properties on the structure, morphology and spatial arrangement of silicide nanoisland assemblies, identify optimum structures and realize them via computation-guided nanomaterials processing. The project provides insights into developing new nanomagnets by design for potential applications in next-generation Si-based spintronics and other nanodevices.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.