A modulated electron beam is used as a scanning thermal pump to examine the local surface and subsurface flaws of single crystal samples. The electron beam gene rated thermal waves are directly monitored by measuring the surface infrared emission while the longitudinal acoustic waves produced by thermal expansion are monitored simultaneously with a piezoelectric transducer. The results of point-by-point target scans are used to create images of the crystal surfaces. Contrasting images formed by the two techniques are compared as a function of electron beam modulation frequency. The infrared imaging technique is shown to evidence superior resolution.
Dacol, F. and Utterback, S.
"Parallel Acoustic/Infrared Imaging of Single Crystal Surface and Subsurface Structure,"
Scanning Microscopy: Vol. 1
, Article 19.
Available at: https://digitalcommons.usu.edu/microscopy/vol1/iss3/19