ION AND NEUTRAL VELOCITY DISTRIBUTIONS IN MULTI-ION PLASMA SHEATHS

多离子等离子体鞘中的离子和中性速度分布

• 批准号: 0713784
• 负责人: EARL SCIME
• 金额: --
• 依托单位: West Virginia University Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0713784&HistoricalAwards=false
• 关键词: ION; NEUTRAL; VELOCITY; DISTRIBUTIONS; MULTI

The proposal is directed at investigating the physics of multi-ion sheaths, the generation of supersonic fluxes of energetic ions in spontaneously forming double layers (sheaths), and the creation of fluxes of energetic neutrals that could be used for plasma-aided etching. Neutral etching avoids the problem of substrate charging that occurs when energetic ions are used to etch wafers in the microelectronics industry. The acceleration of ions through sheaths in multi-ion plasmas is a fundamental plasma physics question with important ramifications for systems ranging from space plasmas to fusion plasmas. There are two primary objectives of this proposal. First is the determination of the effect of additional ion species on double layer formation in expanding helicon plasmas, and second, the measurement of the momentum coupling between ions and neutral atoms in the layer due to charge exchange processes. The essential intellectual merit of the proposed activity will be the first detailed measurement of the flow velocities of two different ion species and a single neutral species in a plasma sheath. Ion acceleration through pre-sheaths and sheaths in multi-ion plasmas is not fully understood and this project will make a significant contribution to this active area of fundamental plasma science research. The broader impact of the work involves the training of graduate students in a research environment that emphasizes the synergy between basic and applied plasma physics; improvement of the percentage of women obtaining advanced degrees in physics; and attracting high quality undergraduates into physics through involvement in cutting-edge research activities. Impact on the field of plasma etching of semiconductors is also likely since production of significant fluxes of energetic neutral atoms through charge exchange neutralization of the double layer accelerated ions would provide a new means of etching features in silicon at scales of less than ten nanometers. Impact on the field of plasma propulsion is also likely given that plasma detachment from plasma-based thrusters is an important and unresolved question.

该提案旨在研究多离子鞘的物理，在自发形成双层（鞘）中产生能量离子的超音速通量，以及可以用于质量含量蚀刻的能量中性物质的通量。中性蚀刻避免了使用微电子行业蚀刻晶片时发生的底物充电问题。通过多离子等离子体中的离子加速离子是一个基本的等离子体物理问题，对从太空等离子体到融合等离子体的系统具有重要的影响。该提案有两个主要目标。首先是确定其他离子物种对扩展的Helicon等离子体中双层形成的影响，其次，由于电荷交换过程而在层中离子和中性原子之间的动量耦合的测量。所提出活动的基本知识优点将是对两种不同离子物种的流速和血浆鞘中的单个中性物种的首次详细测量。通过在多离子等离子体中的摄影和鞘中加速离子，该项目将为这一基本等离子体科学研究的活跃领域做出重大贡献。这项工作的更广泛影响涉及在研究环境中培训研究生，该研究环境强调了基本血浆物理学和应用等离子体物理学之间的协同作用；提高获得物理高级学位的妇女百分比；通过参与尖端研究活动，吸引高质量的本科生进入物理学。由于双层加速离子的电荷交换中和中和，对半导体的等离子体蚀刻的影响也可能是由于硅酸盐在较小的10纳米计的尺度上产生一种新的蚀刻特征的方法。鉴于基于等离子体的推进器的血浆脱离是一个重要且尚未解决的问题，也可能对等离子体推进的领域的影响。