Mechanics of Strain-Driven Nanopatterning in Alloy Systems

合金系统中应变驱动的纳米图形力学参考文献：Vivek B. Shenoy，布朗大学由于集成电路技术正在接近其现有光刻图形方法的物理极限，因此需要提高空间分辨率的新方法来保持这个价值2000亿美元的市场稳定。由弹性相互作用驱动的自组装方法被广泛认为是制造纳米线、量子点和纳米级表面图案等结构的一种有前途的技术。然而，要遵循此方法并以期望的方式创建结构，必须采用可靠的方法来设计自组装过程中模式采用的大小和形状。在提出的工作中，合金将被探索作为一种手段来实现对表面上应变自组装结构的形状、大小和空间图案的控制。研究人员将开发计算模型，以解释合金系统的独特特征，例如由形貌相关弹性场引起的输运性质和偏析的差异。材料参数的组成和应变依赖关系将通过原子尺度模拟得到。研究者与半导体行业的一个实验小组有着密切的联系，这将允许对所提议的建模工作进行直接评估。该项目将开发的多尺度方法将广泛适用于分析各种材料系统中的纳米尺度图案，但当前的重点将是硅表面与Ge的合金化。Ge/Si系统的优势在于，除了在可再生能源设备和生物传感器方面的潜在应用之外，它还与发达的Si集成电路制造技术自然兼容。该项目将为学生提供一个与半导体行业的实验人员合作的机会，并发展先进的计算技能。在这个项目中训练的学生将很好地定位在学术界，半导体和能源行业的职业生涯。在计算方法方面取得的进展将包括在PI创建的课程中，以促进动手模拟经验。

CMMI 0855853: Mechanics of Strain-Driven Nanopatterning in Alloy SystemsPI: Vivek B. Shenoy, Brown UniversityAs integrated circuit technologies are approaching their physical limitations with current lithographic patterning methods, new approaches with improved spatial resolution are required to keep this $200 billion market stable. A bottom up or self-assembly approach driven by the elastic interactions is widely viewed as a promising technique for the fabrication of structures such as nanowires, quantum dots and nanoscale surface patterns. However, to follow this approach and create structures in a desired manner, a reliable means to engineer the size and shapes that the patterns adopt during self-assembly is essential. In the proposed work, alloying will be explored as a means to achieve control over the shape, size and spatial pattering of strained self-assembled structures on surfaces. The investigator will develop computational models that accounts for features unique to alloyed systems such as differences in transport properties and segregation induced by morphology dependent elastic fields. The composition and strain dependence of the material parameters will be obtained from atomic scale simulations. The investigator has close ties with an experimental group based in the semiconductor industry, which will allow for direct assessment of the proposed modeling effort. The multiscale methods that will be developed in the project will be broadly applicable to analyze nanoscale patterning in a variety of material systems, but the immediate focus will be on alloying of Si surfaces with Ge. The Ge/Si system has the advantage that in addition to potential applications in renewable energy devices and biological sensors, it is also naturally compatible with the well developed Si integrated circuit fabrication technology. The project will provide an opportunity for students to both collaborate with experimentalists in the semiconductor industry and to develop advanced computational skills. The students trained on this project will be well positioned to pursue careers in academia and in the semiconductor and energy industries. The progress made in the computational methods will be included in the course that the PI has created to promote hands-on simulation experience.