Surface Plasmon Photoacoustic Imaging of Subsurface Objects

地下物体的表面等离子体光声成像

• 批准号: 1031574
• 负责人: Oluwaseyi Balogun
• 金额: $ 27万
• 依托单位: Northwestern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1031574&HistoricalAwards=false
• 关键词: Surface; Plasmon; Photoacoustic; Imaging; Subsurface

This project seeks to develop a novel photoacoustic (PA) microscopy system that would enable the mapping of deeply buried subsurface defects in optically opaque materials. Imaging of subsurface objects with sub-100 nm dimensions in opaque materials remains a major concern to integrated circuit reliability and performance. PA techniques combine the benefits of the large penetration depth of ultrasound with the lateral spatial resolution of an optical probe. However, the spatial resolution of PA techniques is limited by diffraction. To overcome these challenges, a novel approach is proposed for sub-wavelength PA technology by creating highly localized optical and ultrasound fields using: a) surface plasmonc nano-focusing for sub-100 nm confinement of the optical probe for high sensitivity detection of laser generated high frequency (0.5 - 10 GHz) ultrasound, and b) time reversal acoustics for spatial focusing of the scattered ultrasound field from nanoscale sub-surface objects. This PA system would provide an unprecedented spatial resolution and penetration depth for imaging sub-surface defects in microelectronic devices. The educational and out-reach programs proposed are deigned to excite high school level students to pursue careers in STEM and provide unique multidisciplinary training opportunities for graduate and undergraduate students in the area of photoacoustic imaging.

该项目旨在开发一种新型光声 (PA) 显微镜系统，能够对光学不透明材料中深埋的次表面缺陷进行绘图。对不透明材料中尺寸低于 100 nm 的地下物体进行成像仍然是集成电路可靠性和性能的主要关注点。 PA 技术结合了超声波大穿透深度和光学探头横向空间分辨率的优点。 然而，PA 技术的空间分辨率受到衍射的限制。为了克服这些挑战，提出了一种亚波长 PA 技术的新方法，通过使用以下方法创建高度局部化的光学和超声场：a) 表面等离子体纳米聚焦，用于光学探头的亚 100 nm 限制，以高灵敏度检测所产生的激光高频 (0.5 - 10 GHz) 超声波，以及 b) 时间反转声学，用于对来自纳米级地下物体的散射超声波场进行空间聚焦。该 PA 系统将为微电子器件中的次表面缺陷成像提供前所未有的空间分辨率和穿透深度。拟议的教育和推广计划旨在激发高中生从事 STEM 职业，并为光声成像领域的研究生和本科生提供独特的多学科培训机会。