Sub-Surface Structural Damages in Laser-assisted Surface Nanostructuring: Experimental Characterization and Atomistic Modeling

激光辅助表面纳米结构中的次表面结构损伤：实验表征和原子建模

• 批准号: 0820747
• 负责人: Xinwei Wang
• 金额: $ 10.13万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-02-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0820747&HistoricalAwards=false
• 关键词: Sub; Surface; Structural; Damages; Laser

As a top-down nanofabrication technique, the laser-assisted scanning tunneling microscope (STM) provides a wide variety of potential applications in surface nano-repair, fabrication and characterization of nano- to microscale integrated nanoelectronics and nanophotonics, and machining and aligning of nanoparticles and nanotubes/wires. The nanoscale residual stress/strain and structural damages in surface nanostructures fabricated using laser-assisted STM can significantly change the local mechanical, thermal, optical, and electronic characteristics, thereby degrading the functionality and reliability of surface nanostructures. Targeting this critical problem, the objectives of the project are to (1) develop the knowledge base about the underlying physics in the formation of sub-surface nanoscale structural damages in surface nanostructuring with laser-assisted STM, and (2) explore and identify how and to what extent the experimental parameters affect the formation of sub-surface nanoscale structural damages. Significant insights into strain and structural damages at molecular/atomic levels in nanostructuring by laser-assisted STM will be attained using both scanning tunneling spectroscopy and high-resolution transmission electron microscopy. This represents the early attempts to quantitatively explore the characteristics of the residual strain and structural damages at such a small scale. This large-scale molecular dynamics simulation will provide fundamental and dynamic understanding of the development and propagation/migration of both stress/strain and structural damages in surface nanostructuring with laser-assisted STM. These strategically combined experimental and numerical investigations will reveal the correlations between residual strain and structural damages and varied experimental parameters.The anticipated outcomes are instrumental for minimizing residual stress/strain and structural damages and improving the function/performance and dependability of micro/nanoscale systems. Sufficient insights into the mechanisms and driving forces behind the formation of nanoscale structural damages will lead to the establishment of basic knowledge building blocks required for successful development of the nanostructuring technology with laser-assisted STM and its implementation to industries. Results of the research will be broadly disseminated through presentations at professional conferences, publications in highly visible refereed journals, across-department seminars, and a dedicated project website. The research results will be integrated into new courses "Heat Transfer at Nanoscales and in Ultra-short Time Domain" and "Introduction to Nanotechnology." Extensive undergraduate participation will be involved via summer research employment. Special efforts will be taken to recruit graduate and undergraduate students from groups traditionally underrepresented in higher education, particularly women and minorities. A specially designed website will be developed for instructional functions for K-12 students.

As a top-down nanofabrication technique, the laser-assisted scanning tunneling microscope (STM) provides a wide variety of potential applications in surface nano-repair, fabrication and characterization of nano- to microscale integrated nanoelectronics and nanophotonics, and machining and aligning of nanoparticles and nanotubes/wires.使用激光辅助的STM制造的表面纳米结构中的纳米级残留应力/应变和结构性损伤可以显着改变局部机械，热，光学和电子特性，从而降低表面纳米结构的功能和可靠性。 Targeting this critical problem, the objectives of the project are to (1) develop the knowledge base about the underlying physics in the formation of sub-surface nanoscale structural damages in surface nanostructuring with laser-assisted STM, and (2) explore and identify how and to what extent the experimental parameters affect the formation of sub-surface nanoscale structural damages. 通过扫描隧道光谱和高分辨率透射电子显微镜，将获得对激光辅助STM在纳米结构中分子/原子水平上应变和结构损伤的重要见解。这代表了在如此小的规模上定量探索残余应变和结构性损害的特征的早期尝试。这种大规模的分子动力学模拟将提供对具有激光辅助STM的表面纳米结构中应力/应变和结构性损害的发展和传播/迁移的基本和动态理解。这些策略性地结合的实验和数值研究将揭示残余应变与结构性损害与各种实验参数之间的相关性。预期的结果对最大程度地减少了残余应力/应变和结构损害，并改善了微观/纳米级系统的功能/性能和可靠性。对纳米级结构损害形成背后的机制和驱动力的充分见解将导致建立成功开发纳米结构技术所需的基本知识构建块，并使用激光辅助的STM及其对行业实施。 这项研究的结果将通过在专业会议上的演讲，高度可见的裁判期刊，跨部门研讨会和专门的项目网站上进行广泛传播。该研究结果将纳入新课程中，“纳米级的热传递以及超短暂的时间领域”和“纳米技术简介”。通过夏季研究工作将参与广泛的本科参与。将采取特殊努力来招募从传统上人数不足的小组，尤其是妇女和少数群体中的人数不足的团体招募研究生和本科生。专门设计的网站将用于K-12学生的教学功能。