Exploring Size Dependent Brittle-to-Ductile Transition in Single Crystal Silicon Using High Temperature MEMS

使用高温 MEMS 探索单晶硅中与尺寸相关的脆性到延性转变

• 批准号: 1102201
• 负责人: Taher Saif
• 金额: $ 36万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1102201&HistoricalAwards=false
• 关键词: Exploring; Size; Dependent; Brittle; Ductile

The objectives of this program are to (a) measure brittle-to-ductile (BDT) temperature in Single Crystal Silicon (SCS), widely used in micro/nano scale devices, as a function of size, and (b) unravel the mechanisms of size dependence of BDT. The temperature at which materials become ductile from brittle is known as BDT temperature. At macro scale, BDT is independent of size. There is emerging evidence suggesting that at nano scale, BDT temperature becomes size dependent, although the underlying mechanism is unclear, which this program seeks to explore. The research will be conducted by developing a novel SiC micro mechanical stage that allows testing micro/nanometer scale specimens at room to 1000C while visualizing their microstructure in scanning or transmission electron microscopes.The intellectual merit is that the project explores a fundamental question: how BDT temperature becomes size dependent. Its working hypothesis is, BDT is caused by a sudden increase in density and mobility of crystalline defects such as dislocations. The energy required to activate dislocations from the surface is substantially smaller than that from the bulk. Hence BDT temperature decreases with size. Broader impact: Research will be integrated with education and outreach by developing a hands-on instructional module, and recruiting REU students from diverse backgrounds. Due to collaborations with the Universities of Vienna and of Leoben, Austria, the participants will gain international experience.The study could be transformative if it shows that BDT is size dependent in pure SCS, and its underlying mechanism. The study may offer a new paradigm in the understanding of SCS.

该程序的目标是（a）在单晶硅（SCS）中测量脆性至脱糖（BDT）温度，该温度广泛用于微/纳米尺度设备，作为大小的函数，以及（b）阐明BDT大小依赖的机制。易碎物质延性的温度称为BDT温度。在宏观量表上，BDT独立于大小。有新兴的证据表明，在纳米尺度上，BDT温度依赖于大小，尽管尚不清楚基本机制，该程序试图探索它。这项研究将通过开发新型的SIC微型机械阶段来进行，该阶段允许在扫描或传输电子显微镜中可视化其微观结构的同时测试微型/纳米尺度标本，同时可视化1000c。智力优点是该项目探索了一个基本问题：BDT温度如何依赖BDT。它的工作假设是，BDT是由晶体缺陷（例如位错）的密度和迁移率突然增加引起的。从表面激活脱位所需的能量大大比整体所需的能量要小得多。因此，BDT温度随大小而降低。 更广泛的影响：研究将通过开发动手教学模块，并招募来自不同背景的REU学生，与教育和外展融合。由于与维也纳大学和奥地利莱本大学的合作，参与者将获得国际经验。如果这表明BDT的规模取决于纯SC及其基本机制，那么这项研究可能会进行变革。该研究可能会在理解SCS方面提供新的范式。