Scanning near-field ultrasound holography

Scanning near-field ultrasound holography (SNFUH) is a method for performing nondestructive nano-scale high-resolution imaging of buried and embedded structures.

SNFUH is a type of scanning probe microscopy (SPM) technique that provides depth information as well as spatial resolution at the 10 to 100 nm scale.

[1] Gajendra S. Shekhawat and Vinayak P. Dravid of Northwestern University (Evanston, IL, USA) developed SNFUH in 2005.

The perturbations to phase and amplitude of the surface acoustic standing wave are locally monitored by the antenna via the lock-in approach and the SPM electronic module.

This technique takes advantage of both the phase and amplitude of scattered ultrasound waves to produce nanoscale resolution images of internal substructures.