Title :
Rayleigh acoustic mode in aluminum nitride films
Author :
Carlotti, G. ; Fioretto, D. ; Giovannini, L. ; Palmieri, L. ; Socino, G. ; Verdini, L. ; Verona, E.
fDate :
Oct. 31 1994-Nov. 3 1994
Abstract :
Brillouin light scattering has been used for studying the propagation of the surface Rayleigh mode in AlN films grown by R.F. reactive diode magnetron sputtering on (1-11)-Si substrate. Since the velocity of the shear vertical wave in the film is higher than that in the substrate, the structure is of the type fast film/slow substrate. The evolution of the Rayleigh wave has been analyzed experimentally on films of different thickness between 20 nm and 1.2 μm. The Rayleigh mode exist up to a cutoff value of the ratio h/Λ. For higher values of this parameter this wave becomes a leaky mode radiating energy into the substrate. Measurement of its phase velocity enabled us to determine the value of the effective elastic constant c44 of the film
Keywords :
Brillouin spectra; III-V semiconductors; Rayleigh waves; aluminium compounds; elastic constants; piezoelectric semiconductors; piezoelectric thin films; semiconductor thin films; sputtered coatings; (1-11)-Si substrate; AlN; Brillouin light scattering; RF reactive diode magnetron sputtering; Rayleigh acoustic mode; Si; aluminum nitride films; elastic constant; fast film/slow substrate structure; leaky mode; phase velocity; shear vertical wave; surface mode; Aluminum materials/devices; Brillouin scattering; Leaky waves; Mechanical factors; Piezoelectric films/devices; Piezoelectric semiconductor materials/devices; Semiconductor films; Sputtering; Surface acoustic waves;
Conference_Titel :
Ultrasonics Symposium, 1994. Proceedings., 1994 IEEE
Conference_Location :
Cannes, France
Print_ISBN :
0-7803-2012-3
DOI :
10.1109/ULTSYM.1994.401629
