J. Phys. IV France 129 (2005) 61-63
DOI: 10.1051/jp4:2005129013

Mapping of microwave-induced phonons by -Brillouin spectroscopy: Hypersound in ZnO on Silicon

J. Mainka^{1, 2}, L. Le Brizoual^{1, 3}, J.K. Krüger^{1, 2}, O. Elmazria^{1, 3}, B. Vincent^{1, 3}, D. Rouxel^{1, 3}, P. Alnot^{1, 3} and R. Sanctuary<sup>1, 4

1</sup>  Laboratoire Européen de Recherche Universitaire : Saarland-Lorraine
²  Experimentalphysik, Universität des Saarlandes, Bau 38, 66041 Saarbrücken, Germany
³  Laboratoire de Physique des Milieux Ionisés et Applications, CNRS-UMR 7040, Université Henri Poincaré, 54506 Nancy I, France
⁴  Laboratoire de Physique des Matériaux, Université du Luxembourg, Campus Limpertsberg, 1511 Luxembourg

Abstract
High performance Brillouin microscopy has been used in order to characterize the spatial distribution of piezoelectrically induced acoustic fields excited at microwave frequencies in a ZnO film deposited on silicon directly within the area of the electrically excited inter-digital transducer (IDT). For a IDT of 300 micrometers length, the maximum of intensity is close to the edge of the transducer and the minimum lies between 200 and 250 micrometers from this maximum. Moreover, an acoustic second harmonic mode is observed for a fundamental excitation frequency of 1 GHz.

© EDP Sciences 2005