Ion Beam Machining to Eliminate Stress-Induced Curvature in Microelectromechanical Systems (MEMS) Optical Devices

离子束加工可消除微机电系统 (MEMS) 光学器件中应力引起的曲率

• 批准号: 0223821
• 负责人: Harley Johnson
• 金额: $ 28.07万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-21 至 2005-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0223821&HistoricalAwards=false
• 关键词: Ion; Beam; Machining; Eliminate; Stress

The objective of this research project is to develop a post-processing technique to planarize curved freestanding thin film microelectromechanical systems (MEMS) devices by means of controlled exposure to a neutral ion beam. The method works by (1) affecting a thin highly stressed layer in the first few seconds of ion beam exposure through atomic rearrangement near the surface of the film; and, (2) removing initially stressed material in the film after several additional minutes of ion beam exposure. These effects can be combined in a controlled way to offset the initial relaxation curvature in the micro-mirror. MEMS micro-mirrors are important components in several next-generation optical communications devices. Freestanding MEMS micro-mirrors are often fabricated in a layer-by-layer process before being released from a host substrate; through-thickness dimensions may be as small as one micron or less. Once these thin structures are released, residual stresses due to processing are relaxed by transverse curvatures large enough to render the devices optically useless. The program includes both theoretical and experimental work. Using analytical and numerical models, the effects of various processing parameters will be studied; experiments will be carried out to test these parameters, and the quality of the resulting planarized mirrors will be characterized.

本研究的目的是开发一种后处理技术，通过控制暴露于中性离子束来平坦化弯曲的独立薄膜微机电系统（MEMS）器件。该方法的工作原理是：（1）在离子束暴露的最初几秒钟内，通过膜表面附近的原子重排影响薄的高应力层;以及（2）在离子束暴露的另外几分钟后，去除膜中的初始应力材料。 这些效应可以以受控的方式组合以抵消微镜中的初始弛豫曲率。 MEMS微镜是下一代光通信器件的重要组成部分。 独立式MEMS微镜通常在从主衬底释放之前在逐层工艺中制造;厚度尺寸可以小至1微米或更小。一旦这些薄结构被释放，由于加工产生的残余应力通过足够大的横向曲率来释放，从而使器件在光学上无用。该计划包括理论和实验工作。 使用分析和数值模型，将研究各种工艺参数的影响;将进行实验来测试这些参数，并将表征所得到的平面化反射镜的质量。