Seeing the Invisible: Scanning Near-Field Ultrasound Holography (SNFUH) for High Resolution Buried Imaging and Pattern Recognition

A novel scanning near-field ultrasound holography (SNFUH) technique has been developed which combines the nanometer-scale spatial resolution of conventional scanning probe microscope (SPM) with the surface and subsurface imaging capabilities [1]. This technique fills the critical void in characterization and investigation of the static and dynamic mechanics of nanoscale systems and address emerging issues in imaging and analysis of diverse “embedded” nano and microscale structures, and engineered systems. The SNFUH development integrates three major approaches: a unique combination of scanning probe microscope platform (which enjoys excellent lateral and vertical resolution) coupled to microscale ultrasound source and detection (which facilitates “looking” deeper into structures, section-by-section) and a novel holography approach (to enhance phase resolution and phase coupling in imaging).