High-density Plasma for Efficient Manufacturing of Electronic Devices

等离子体技术在平板显示器、计算机芯片和太阳能电池板等电子设备的制造中发挥着关键作用。目前用于制造的工业等离子体受到多重限制，包括等离子体密度低(这会减缓加工速度)、大面积均匀性差、等离子体及其产生的材料受到污染以及能源利用效率低下。该奖项支持使用独特的磁增强型感应等离子体源进行高密度等离子体的基础研究。从研究中获得的新知识将导致能够高效制造电子设备和各种薄膜产品的新型等离子体源，显著降低消费电子产品的成本，促进清洁能源的采用，并减少制造对环境的负面影响。该项目将加强大学与行业的合作，增强美国电子行业的经济竞争力。它还将通过培训学生和吸引当地部落学生进入科学和工程专业，为劳动力发展做出贡献。工业等离子体是由强电磁场产生的。等离子体处理的效率主要取决于等离子体密度、等离子体温度以及电子和离子的能量分布。传统的低密度等离子体是由无约束电磁场激发的，这样高能电子可以很容易地从等离子体区域逃逸出来，而高密度等离子体可以通过将高能电子保留在等离子体区域内的受限电磁场来产生，以极大地延长其寿命。受限电场和磁场同时作用于等离子体，并对等离子体产生相互作用。关于受限电磁场产生的高密度等离子体的性质以及初级感应参数(激励频率和磁场分布)对等离子体性质的影响，人们知之甚少。为了填补这一知识空白，研究团队将执行三项任务。首先，使用专用软件COMSOL建立等离子体模拟模型，描述等离子体的基本性质(包括等离子体密度、等离子体温度、电子和离子的能量分布)。其次，利用所建立的模型预测激励频率和磁场分布对等离子体性质的影响。最后，通过实验验证了部分预测结果。例如，将使用朗缪尔探针测量等离子体区域有限点处的等离子体密度和电子能量分布，并使用光学发射光谱仪间接测量整个等离子体区域的等离子体密度。

Plasma technology plays a critical role in manufacturing of electronic devices, such as flat panel displays, computer chips, and solar panels. Industry plasmas currently used for manufacturing suffer from multiple limitations, including low plasma density (which slows processing), poor uniformity over large areas, contamination of plasma and the resulting materials, and inefficient energy use. This award supports fundamental research on high-density plasma using a unique magnetically enhanced inductive plasma source. New knowledge obtained from the research will lead to novel plasma sources that enable efficient manufacturing of electronic devices and various thin-film products, significantly reducing the costs of consumer electronics, promoting the adoption of clean energy, and reducing the negative impact of manufacturing on the environment. This project will strengthen university-industry collaboration and economic competitiveness of the U.S. electronics industry. It will also contribute to workforce development by training students and attracting local tribal students to science and engineering. Industry plasmas are created by strong electromagnetic fields. The efficiency of plasma processing is mainly determined by plasma density, plasma temperature, and energy distribution of electrons and ions. Conventional low-density plasmas are excited by unconfined electromagnetic fields that allow energetic electrons to escape easily from the plasma region, while high-density plasmas can be created by confined electromagnetic fields that retain energetic electrons within the plasma region to greatly extend their lifetime. The confined electric and magnetic fields act simultaneously and have interaction effects on the plasma. Little is known about the properties of high-density plasma created by confined electromagnetic fields and the effects of the primary induction parameters (excitation frequency and magnetic field distribution) on plasma properties. To fill this knowledge gap, the research team will perform three tasks. First, establish a plasma simulation model using dedicated software COMSOL to describe fundamental plasma properties (including plasma density, plasma temperature, and energy distribution of electrons and ions). Second, use the established model to predict effects of excitation frequency and magnetic field distribution on plasma properties. Finally, verify some of the predicted results by experiments. For example, plasma density and electron energy distribution at a limited number of points of the plasma region will be measured using a Langmuir probe, and plasma density over the entire plasma region will be indirectly measured using an optical emission spectrometer.