NU 2003-061 and 2010-051

Inventors

Gajendra S. Shekhawat*

Vinayak P. Dravid

Short Description

A novel nondestructive imaging method (SNFUH) providing nanoscale spatial resolution as well as depth information for embedded structural features.

Abstract

There is an increasing need for nondestructive high-resolution imaging of various 'buried' nano/micro-structures in scientific research and nano/micro-manufacturing process. To fill this critical void, a novel acoustic holography technology, known as the scanning near-field ultrasound holography (SNFUH), has been developed at Northwestern to provide nondestructive real-space imaging of embedded features with nanoscale lateral resolution and depth sensitivity. This invention is based on a unique integration of scanning probe microscope (SPM) platform coupled to microscale ultrasound source with novel detection and holography techniques. The ultrasound wave needed for this imaging technology is generated during the thermal expansion of the samples that absorb the coherent laser beam provided. Significantly outperforming alternative approaches (e.g. AFM) in imaging resolution, SNFUH is equally amenable to hard (e.g. semiconductor), soft (e.g. polymers and biological system), and hybrid materials. This promising technology offers a versatile tool for numerous imaging and structure detection applications in physical sciences, engineered systems, and biology.

Applications

• Nondestructive nanoscale imaging of buried features in engineered systems, such as packaged nano/micro-electronics,
• High resolution imaging of 3D nano/micro structures (hard, soft or hybrid material systems),
• Nondestructive nanoscale imaging of inside structures of biological systems, such as cells,
• Nondestructive detection of internal structural defects at nanoscale.

Advantages

• Nano-scale spatial resolution
• Nondestructive, real-space imaging
• Amenable to different material systems
• Providing depth information

Publications

Shekhawat G.S. and Dravid V.P. (2005) Nanoscale Imaging of Buried Structures via Scanning Near-Field Ultrasound Holography. Science. 310:5745:89-92

IP Status

Issued US patents No. 7,798,001, No. 7,448,269 and No. 8,316,713