SBIR Phase I: Advanced Two-Color Interferometer for Turbulence Correction

SBIR 第一阶段：用于湍流校正的先进双色干涉仪

• 批准号: 9861111
• 负责人: Allen Flusberg
• 金额: $ 10万
• 依托单位: Science Research Laboratory Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9861111&HistoricalAwards=false
• 关键词: SBIR; Phase; Advanced; Two; Color

9861111 This Small Business Innovation Research Phase I project focuses on reducing the minimum feature size that can be written lithographically to integrated circuits (chips!). Critical dimensions below 0.1 um require improved-precision interferometry to measure the position of the stage that holds the wafer. Although the stability of current laser gauges can be improved to attain a precision of less than 1 nm in constant-density air, these gauges cannot correct for air-density variations (turbulence). As a result, turbulence presently limits overlay precision to 20-30 nm. This imprecision is unacceptably large for 0.1 um design-rule lithography, for which scaling estimates show that the stage-position measurement should contribute no more than ~2.5 nm to the overlay error budget. We propose to develop a two-color stand-alone laser gauge that measures both the turbulence correction and the absolute stage position simultaneously. A major advantage is that one of the colors can be the He-Ne 633-nm line, which is used in nearly all current commercial laser gauges. This research will lead to a low-cost ( ~$60,000), ultra-compact instrument that will decrease the contribution of the laser gauge to the overlay error to 2 nm. Phase I will prove the feasibility of the two-color technique, and Phase II will be a proof-of-principle demonstration. Since the elimination of turbulence effects on laser-gauge precision will become progressively more critical as the required resolution with which steppers must overlay successive lithographic wafer exposures improves, commercial demand for the proposed instrument by stepper manufacturers is certain to be strong, with an anticipated market of $60 million by the year 2004. The proposed instrument will then facilitate the development of steppers with sub-0.1 um minimum feature sizes and improve their resolution.

9861111 这个小型企业创新研究第一阶段项目的重点是减少可以光刻写入集成电路（芯片！）的最小特征尺寸。低于0.1 μ m的临界尺寸需要改进的精度干涉测量来测量保持晶片的载物台的位置。虽然目前的激光测量仪的稳定性可以提高，以达到在恒定密度的空气中小于1纳米的精度，这些仪器不能校正空气密度的变化（湍流）。因此，湍流目前将重叠精度限制在20-30 nm。这种不精确度对于0.1 μ m设计规则光刻来说是不可接受的大，对于该光刻，缩放估计表明台位置测量对重叠误差预算的贡献不应超过~2.5 nm。我们建议开发一种双色独立激光测量仪，同时测量湍流校正和绝对平台位置。一个主要的优点是，其中一种颜色可以是He-Ne 633 nm线，这是在几乎所有目前的商业激光测量仪使用。这项研究将产生一种低成本（约60，000美元）的超紧凑型仪器，将激光测量仪对重叠误差的贡献降低到2 nm。第一阶段将证明双色技术的可行性，第二阶段将是原理验证演示。 由于消除湍流对激光测量精度的影响将变得越来越重要，因为步进机必须覆盖连续光刻晶片曝光所需的分辨率提高了，步进机制造商对所提出的仪器的商业需求肯定是强劲的，预计到2004年市场将达到6000万美元。拟议的仪器，然后将促进与次0.1微米的最小特征尺寸的步进器的发展，并提高其分辨率。