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

NER：超临界二氧化碳辅助沉积和金属氧化物薄膜的界面性质。NSF纳米级探索性研究PI：Theodsia Gousi教授，马里兰大学巴尔的摩县分校物理系本提案是对NSF 04-043类纳米科学与工程倡议的响应。这项研究的目的是研究超临界流体的救助力是否可以用来沉积具有良好界面性能的薄绝缘膜。主流的真空基沉积技术通常受前驱体低蒸汽压的限制，通过在加热的衬底(300℃)上进行化学反应，利用可溶的有机氧化物和金属有机前驱体在表面进行高压反应，b)为薄膜的形成提供能量，c)完成反应副产物的去除。这项研究是重要的，因为未来的纳米器件的制造可能需要在图案化的表面上形成多层微型化结构，可能涉及到在微孔结构和温度敏感材料上沉积有机或生物分子。纳米材料具有与块体材料不同的性质，因为与体积相比，纳米材料的表面和界面所占的比例很大。因此，界面现象很重要，因为它们定义了纳米设备的操作。传统的化学气相沉积技术不能在深井、窄井或多孔材料内部沉积均匀的薄膜。它们涉及增加不良界面反应性的高温步骤，并将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处理可以提供一条低温途径，以在图案化表面或微孔结构上沉积均匀、高纯度、具有良好界面特性和质量的薄膜，影响纳米电子学、分子电子学、生物催化、NEMS和生物NEMS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.