Thin-film characterization using a scanning laser acoustic microscope with surface acoustic waves.
The use of surface acoustic waves in a scanning laser acoustic microscope for the characterization of the mechanical or acoustic properties of thin films deposited on piezoelectric substrates is demonstrated. Quantitative measurements of mass loading effects of 5000-A-thick tungsten films deposited on lithium niobate substrates were obtained using 100-MHz surface acoustic waves. No information about the tungsten film could be obtained using 100-MHz compressional waves. Methods of generating surface waves on nonpiezoelectric materials so that this technique could be used on arbitrary substrates are discussed.
Robbins
W P
WP
Dept. of Electr. Eng., Minnesota Univ., Minneapolis, MN.
Mueller
R K
RK
Rudd
E
E