NER: Supercritical Carbon Dioxide Assisted Deposition and Interfacial Properties of Metal Oxide Thin Films

超临界二氧化碳辅助沉积及金属氧化物薄膜的界面特性。NSF纳米尺度探索性研究项目负责人：Theodosia gougoui教授，马里兰大学巴尔的摩分校物理系。该提案是对纳米尺度科学与工程计划（NSF 04-043， NER类别）的回应。本研究的目的是探讨超临界流体的拯救力是否可以用来沉积具有良好界面性能的薄绝缘膜。主流的真空沉积技术通常是受前驱体蒸气压低限制的质量传输，在加热的基片（300℃）上进行化学反应，高压过程使用可溶性有机过氧化物和金属有机前驱体到表面，b)为薄膜形成提供能量，C)完成反应副产物的去除。这项研究很重要，因为未来的纳米级设计可能需要在图案表面上形成多层小型化结构，并且可能涉及微孔结构和温度敏感材料（如有机或生物分子）上的沉积。纳米材料具有不同于块状材料的性能，因为其表面和界面的比例与体积相比非常重要。因此，界面现象很重要，因为它们定义了纳米器件的操作。传统的化学气相沉积技术无法在深、窄的井或多孔材料内部沉积均匀的薄膜。它们涉及高温步骤，增加了不希望的界面反应性，并且会破坏或使大多数有机/生物分子失去活性。在超临界二氧化碳中进行处理可以为在图案表面或微孔隙结构上沉积均匀、高纯度、具有理想界面性能和质量的薄膜提供低温途径，影响纳米电子学、分子电子学、生物催化、NEMS和bioNEMS等技术领域。学生将接受这些新方法的培训，为更广泛地实施这些技术提供所需的人力基础设施。

NER: Supercritical carbon dioxide assisted deposition and Interfacial properties of metal oxide thin films.NSF Nanoscale Exploratory ResearchPI: Prof. Theodosia GougousiDepartment of Physics, University of Maryland Baltimore CountyThis proposal was received in response to Nanoscale Science and Engineering initiative, NSF 04-043, category NER. The objective of this research is to investigate whether salvation forces from supercritical fluids can be used to enable deposition of thin insulating films with good interfacial properties. Mainstream vacuum-based deposition techniques are usually mass transport limited by the low vapor pressure of the precursors, and proceed through a chemical reaction on a heated substrate (300 C), high pressure process that uses soluble organic peroxides and metal organic precursors to a surface, b) provide energy for film formation, and c) accomplish reaction by-product removal.This research is important because fabrication of future nanoscale devise may entail formation of multilayer miniaturized structures on patterned surfaces, and may involve depositions on microporous structures and on temperature sensitive materials such as organic or biological molecules. Nanoscale materials have different properties from bulk materials because the proportion of surfaces and interfaces in significant compared to the volume. As a result, interface phenomena are important because they define the operation of nanodevices. Conventional chemical vapor deposition techniques are unable to deposit uniform films on deep, narrow wells or inside porous materials. They involve high temperature steps that augment undesirable interface reactivity and would either destroy or render inactive most organic/biological molecules. Processing in supercritical carbon dioxide may provide a low temperature avenue for the deposition of uniform, high purity, thin films, with desirable interfacial properties and quality on patterned surfaces or microporpous structures, impacting technological fields such nanoelectronics, molecular electronics, biocatalysis, NEMS and bioNEMS. Students will be trained in these novel approaches providing the human infrastructure required for the wider implementation of these techniques.