Collaborative Research: GOALI - Non-Equilibrium Processes, Stability, Design and Control of Pulsed Plasmas for Materials Processing

合作研究：GOALI - 用于材料加工的脉冲等离子体的非平衡过程、稳定性、设计和控制

• 批准号: 1500126
• 负责人: Mark Kushner
• 金额: $ 1.5万
• 依托单位: Regents of the University of Michigan - Ann Arbor
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2018-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1500126&HistoricalAwards=false
• 关键词: Collaborative; Research; GOALI; Non; Equilibrium

The goal of this project is to investigate the science and technology of pulsed plasma processing of semiconductor wafers aimed towards developing a knowledge base that will enable pulsed plasmas to be optimized for materials modification. Plasma assisted materials processing is largely responsible for the impressive progress that continues to be made in production of microelectronics devices of ever increasing capability. Plasma etching is the only known, industrially implementable method to fabricate the nanometer sized features in logic and memory chips. During plasma etching, fluxes of ions and neutral particles are directed towards the wafer being processed. The energy and angle of impact of the particles onto the surface of wafers are the critical parameters for the fabrication of microelectronic devices, as well as nanostructured and biocompatible materials. Control of these parameters allows for finer control of the surface composition and, in microelectronics fabrication, etch rate. Low temperature plasmas for plasma materials processing have traditionally used continuously excited plasmas. However, all major semiconductor chip and equipment manufacturers are predicting that pulsed plasmas will be the enabling technology for achieving sub-10 nanometer feature sizes. The most direct impact of this research is addressing fundamental science issues that are of paramount importance to the plasma processing of high performance microelectronics, nanostructures and biocompatible materials. In addition to the technological broader impacts, this project will be highly focused on educational outreach. Prof. Gekelman is one of the founders of LAPTAG (Los Angeles Physics Teachers Alliance Group) and several LAPTAG students and will be involved in these plasma processing studies. Prof. Kushner, director of the Michigan Institute of Plasma Science and Engineering, will leverage those resources to launch the Plasma Picture of the Day website with the goal of providing informative images of plasmas to educate the general public and school children about plasmas.The lack of fundamental understanding of the dynamics of pulsed plasma systems is the current impediment to widespread adoption. For example, instabilities and waves are nearly universally observed in pulsed plasmas, and particularly in electronegative plasmas, which sometimes prevents operation in desirable parameters spaces. The sources of these instabilities and the means to prevent them are not understood. Pulsed plasma processing can be arbitrarily complex. For example, modern capacitively coupled plasma etching tools may be driven by up to 3 separate power supplies at different frequencies which can be pulsed independently at different repetition rates and different duty cycles. The combinations of parameters can number into the millions. This extremely large parameter space places a large premium on having a fundamental understanding of pulsed plasma processing and so be able to predict plasma performance. In this research project, a highly collaborative experimental-modeling effort will investigate the fundamental properties of pulsed plasmas as used in materials processing, with an emphasis on instabilities and waves, diagnosing and modeling the dynamics of the transition from interpulse afterglow to powered plasma, and the means to improve uniformity through pulsing. Laser induced fluorescence will be used to characterize the trajectory of ions as they are accelerated through the transient sheaths produced by pulsed plasmas; and will be correlated with Langmuir probe measurements of plasma properties. Multi-dimensional computer modeling will be validated by these measurements and will be further used to illuminate fundamental issues related to plasma transport in pulsed systems.

该项目的目的是研究半导体晶片的脉冲等离子体处理的科学和技术，旨在开发知识库，该知识库将使脉冲等离子体能够优化材料修饰。血浆辅助材料加工在很大程度上是为了使能力越来越多的微电子设备的生产中所取得的令人印象深刻的进步。等离子体蚀刻是唯一可以在逻辑和记忆芯片中构建纳米尺寸特征的工业实现方法。在血浆蚀刻过程中，离子和中性颗粒的通量针对晶圆的处理。颗粒上晶圆表面的能量和影响角是制造微电器设备以及纳米结构和生物相容性材料的关键参数。对这些参数的控制可以更好地控制表面组成，并且在微电子制造中，蚀刻速率。血浆材料处理的低温等离子体传统上使用了连续激发的等离子体。但是，所有主要的半导体芯片和设备制造商都预测，脉冲等离子体将是实现低于10纳米特征尺寸的能力技术。 这项研究的最直接影响是解决基本科学问题，这对于高性能微电子，纳米结构和生物相容性材料的血浆处理至关重要。除了技术更广泛的影响外，该项目还将高度关注教育外展。 Gekelman教授是Laptag（洛杉矶物理教师联盟小组）和几个Laptag学生的创始人之一，将参与这些等离子体处理研究。密歇根州等离子体科学与工程研究所主任库什纳教授将利用这些资源来启动日常网站的等离子图片，目的是提供有关等离子体的信息图像，以教育普通公众和学童有关等离子体的知识。缺乏对脉冲血浆系统的基本理解，即目前的动态性能是促进了人们对脉冲的影响。例如，在脉冲等离子体中，尤其是在电负性等离子体中，几乎普遍观察到不稳定性和波浪，这有时会阻止在理想的参数空间中运行。这些不稳定性的来源和防止它们的手段尚不理解。脉冲血浆处理可能是任意复杂的。例如，现代的电容性等离子体蚀刻工具可以由多达3个单独的电源以不同的频率驱动，这些频率可以以不同的重复速率和不同的占空比独立脉冲。参数的组合可以数百万。这个极大的参数空间使对脉冲血浆处理的基本了解具有很大的溢价，因此能够预测血浆性能。在该研究项目中，一项高度协作的实验模型工作将调查材料处理中使用的脉冲等离子体的基本特性，并着重于不稳定性和波浪，诊断和建模从插孔余潮到电力等离子体的过渡的动态，以及通过脉冲来改善均匀性的手段。激光诱导的荧光将用于表征离子的轨迹，因为它们通过脉冲等离子体产生的瞬态鞘加速。并将与血浆特性的Langmuir探针测量相关。多维计算机建模将通过这些测量值验证，并将进一步用于阐明与脉冲系统中血浆传输相关的基本问题。