Microplasma for Dry Etching: New Approaches for Micro and Nano Systems

用于干蚀刻的微等离子体：微纳米系统的新方法

• 批准号: 0233174
• 负责人: Yogesh Gianchandani
• 金额: $ 23.86万
• 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: 2002
• 资助国家: 美国
• 起止时间: 2002-01-01 至 2005-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0233174&HistoricalAwards=false
• 关键词: Microplasma; Dry; Etching; New; Approaches; Microplasma; Dry; Etching; New; Approaches

0100366GianchandaniPlasma processing is routinely used in semiconductor processing applications, and is the dominant technique for silicon etching. Conventional etchers aim to create a uniform plasma across the process chamber in which the silicon wafers are located. However, there are applications in micromachining and nanotechnology in which alternative paradigms may prove useful. For example, present fabrication techniques are not practical for manufacturing an array of trenches with 100 different depths, which would require 100 lithography steps. Such a array could be useful for applications like biological cell sorting.This proposal addresses questions pertaining to the science and technology of spatially confined reactive plasmas (microplasmas) and their application to the etching of silicon and other materials. In particular, it focuses on in-situ microplasmas, which are generated by electrodes patterned on the silicon wafer itself. The viability of this concept, which differs radically from other recent work in microplasmas, has been demonstrated by preliminary experiments in which in-situ DC microplasmas were used to etch completely through a silicon wafer in less than one hour. The proposed effort will explore the physics, technology, and diagnostics for reactive microplasmas for etching silicon and other materials.A number of etching configurations will be examined for their impact on plasma confinement, etch rates, anisotropy, mask selectivities, and electrode wear. Promising electrode structures will be explored, including options in which the ion flux is electrostatically controlled to locally adjust the etch rate and sidewall profile. Various electrode materials, powering schemes, and gas chemistries will be evaluated. Both in-situ and ex-situ diagnostic tools (including thin-film Langmuir probes) will be developed and used. Spectroscopic analysis will be performed. The dependencies of the Paschen breakdown curve, the molecular behavior of the ambient gas, the ionization rates and the electron energies, as well as the relationship of these parameters to the etch rates and profiles will be explored.Theoretical models will be developed for the reactive microplasmas by refining global plasma analysis. This includes the incorporation of realistic basic data and consideration of discharge geometry and electrode material. The theoretical models will be used for scaling studies to determine if the plasmas can be reduced to nanometer dimensions. Supporting experiments will be carried out to explore the scaling limits and validate the theory.The proposed reactive microplasmas have the potential not only for making a contribution to traditional etching applications, but also facilitating the fabrication of microstructures that were previously infeasible. Using microplasmas, an array of 100 trenches with different depths could be built with just two masking steps. In addition, if the proposed research is successful, not only will it be possible to individually specify the profile of every trench in the array, but also to skew the direction of the etch with the help of local electric fields controlled by secondary electrodes. In the longer term, the proposed research could lead to other avenues of research, including localized deposition by sputtering or plasma enhanced chemical vapor deposition (PECVD).

0100366GianChandaniplasma处理通常用于半导体处理应用中，是硅蚀刻的主要技术。传统的蚀刻剂旨在在硅晶片所在的过程室内创建一个均匀的等离子体。但是，在微加工和纳米技术中有一些应用，其中替代范式可能被证明是有用的。例如，当前的制造技术对于制造具有100个不同深度的一系列沟渠不实用，这将需要100个光刻步骤。这样的阵列对于诸如生物细胞分类之类的应用可能是有用的。该提案解决了与空间限制的反应性等离子体（微质体）的科学和技术有关的问题，以及它们在硅和其他材料的蚀刻方面的应用。特别是，它专注于原位微层，这些微质体是由在硅晶片本身上图案的电极产生的。初步实验证明了这一概念与微质量最近的其他作品的生存能力，在不到一个小时的时间内使用了原位DC微型质量通过硅晶片完全蚀刻。拟议的工作将探索用于蚀刻硅和其他材料的反应性微质体的物理，技术和诊断。将检查数量的蚀刻配置，以实现其对等离子体约束，蚀刻速率，各向异性，面膜选择性和电极磨损的影响。将探索有希望的电极结构，包括对离子通量进行静电控制以局部调整蚀刻速率和侧壁轮廓的选项。将评估各种电极材料，动力方案和气体化学。将开发和使用原位和原位诊断工具（包括薄膜Langmuir探针）。光谱分析将进行。 Paschen分解​​曲线的依赖性，环境气体的分子行为，电离速率和电子能的分子行为，以及这些参数与蚀刻速率和谱图的关系。将通过完善全局血浆分析来为反应性微质量分析开发理论模型。这包括掺入现实的基本数据以及排放几何形状和电极材料的考虑。理论模型将用于缩放研究，以确定等离子体是否可以降低为纳米尺寸。将进行支持实验以探索缩放限制并验证理论。拟议的反应性微质体不仅具有对传统蚀刻应用做出贡献的潜力，而且还促进了以前不适的微观结构的制造。使用微质量，只需两个掩盖步骤即可建造具有不同深度的100个沟渠的阵列。此外，如果提出的研究成功，不仅可以单独指定阵列中每个沟渠的轮廓，而且还可以借助由次级电极控制的局部电场偏向蚀刻的方向。从长远来看，拟议的研究可能导致其他研究途径，包括通过溅射或血浆增强化学蒸气沉积（PECVD）的局部沉积。