CAREER: Continuous, Vapor-phase Manufacturing of Anisotropic Silicon Nanostructures for Optoelectronic Applications

该学院早期职业发展（CAREER）资助将创建全新的气相制造路线，以实现不同类型和形状的硅纳米结构。硅纳米结构在发光器件（LED）和其他光电器件中具有巨大的应用潜力。对纳米结构形状（无论是球形还是细长的）的快速控制使得在这些应用中具有多功能性。各向异性硅纳米结构已经吸引了越来越多的关注，因为它们表现出不同于球形纳米结构的光电特性，并且可以显著改善LED和其他光电器件的性能。 挑战在于，目前用于制造各向异性硅纳米结构的制造策略需要高温、长反应时间、批处理或有毒溶剂工艺，严重限制了它们的部署和纳入现有制造基础设施。该奖项支持研究发现，表征和建模新的气相合成硅纳米棒的技术使用流通过程，包括等离子体反应器。这些技术提供了可持续性和可扩展性，并无缝集成到器件制造流程中，因此有利于开发利用各向异性硅纳米结构独特和新颖特性的新型多功能器件。一个社会效益是，节能设备的可用性将减少化石燃料的消耗。这项研究从工程、材料科学、等离子体科学和制造业的不同角度深入研究纳米技术。这项工作的跨领域性质将被利用来改善工程教育，少数民族和女性学生在工程中的参与，以及当纳米技术在能源设备，消费品以及健康和医疗技术中越来越普遍时，公众对纳米技术的广泛理解。一些外展活动将涉及斯巴达夫人工程营和科学Festival.Plasma为基础的反应器方法合成无毒半导体纳米晶体是一些最成功的方法在生产产量，可调的纳米尺寸和表面性能，窄尺寸分散性，可控的结晶度。尽管这些反应器具有灵活性，但迄今为止，使用流通式等离子体反应器生产的纳米结构仅是球形各向同性的，限制了等离子体方法的有用性。这项研究代表了使用等离子体控制纳米结构形状的突破，试图将它们与其他气相方法结合使用，以合成具有可调特性的硅纳米棒。该项目的目标是创造一种新的，连续的，气相路线的硅纳米棒的合成，同时进行原位反应表征，以构建在等离子体环境中的纳米结构生长的模型。这项工作将建立在光电功能纳米结构库的基础上，这些纳米结构价格低廉，对环境无毒，同时填补了等离子体反应器用于多功能纳米制造的知识空白。

This Faculty Early Career Development (CAREER) grant will create brand new vapor-phase only manufacturing routes for achieving silicon nanostructures of varying types and shapes. Silicon nanostructures have great potential for use in light-emitting devices (LEDs) and other optoelectronic devices. Exerting control over the nanostructure shape, whether spherical or elongated, enables versatility in these applications. Anisotropic silicon nanostructures have attracted increasing attention because they demonstrate optoelectronic characteristics that differ from those of spherical nanostructures and can offer dramatic improvement in the performance of LEDs and other optoelectronic devices. The challenge is that current manufacturing strategies for making anisotropic silicon nanostructures require high temperatures, long reaction times, batch processing, or toxic solvent processes, severely limiting their deployment and incorporation into existing manufacturing infrastructure. This award supports research into discovering, characterizing, and modeling novel vapor-phase only techniques for synthesizing silicon nanorods using flow-through processes, including plasma reactors. These techniques offer sustainability and scalability paired with seamless integration into device manufacturing streams, therefore benefitting the development of new versatile devices that exploit the unique and novel properties of anisotropic silicon nanostructures. One societal benefit is that the availability of energy-efficient devices will reduce fossil fuel consumption. This research delves into nanotechnology from the diverse standpoints of engineering, materials science, plasma science, and manufacturing. The cross-cutting nature of this work will be leveraged to improve engineering education, engagement of minority and female students in engineering, and broad public understanding of nanotechnology at a time when it is increasingly ubiquitous in energy devices, consumer products, and health and medical technology. Some of the outreach activities will involve Lady Spartans engineering camp and Science Festivals.Plasma-based reactor approaches for the synthesis of nontoxic semiconductor nanocrystals are some of the most successful methods in terms of production yield, tunable nanocrystal size and surface properties, narrow size dispersity, and controllable crystallinity. Despite the flexibility of these reactors, to date the nanostructures produced using flow-through plasma reactors have been exclusively spherically isotropic, limiting the usefulness of the plasma approach. This research represents a breakthrough in using plasmas to control the shape of nanostructures by seeking to use them in combination with other vapor-phase approaches to synthesize silicon nanorods with tunable properties. The objectives of this project are to create a novel, continuous, vapor-phase route for the synthesis of silicon nanorods while simultaneously performing in-situ reaction characterization to construct a model of nanostructure growth in the plasma environment. This work will build on the library of optoelectronically functional nanostructures that are inexpensive and environmentally nontoxic while filling knowledge gaps in the use of plasma reactors for versatile nanomanufacturing.