Accession Number : ADP002466

Title :   Sputtered C-Axis Inclined Piezoelectric Films and Shear Wave Resonators,

Corporate Author : IOWA STATE UNIV AMES

Personal Author(s) : Wang,J. S. ; Lakin,K. M. ; Landin,A. R.

Report Date : 1983

Pagination or Media Count : 7

Abstract : Sputtered piezoelectric films are being studied for potential application to VHF through microwave frequency acoustic wave devices. This paper reports on the growth and characterization of C-axis inclined ZnO and A1N films for shear wave resonators. Orientation relationships for shear wave excitation were calculated for these films which suggest a nearly pure shear wave could be excited with films having C-axis orientation approximately 45 deg. from the surface normal. At other angles, quasi-shear and quasi-longitudinal waves are excited. The well oriented ZnO or A1N films with C-axis inclined from the film normal were grown in a reactive dc planar magnetron sputtering system having an auxiliary anode structure. These films were evaluated by scanning electron microscopy (SEM) and BAW device measurements. The columnar structure of the C-axis crystallites, inclined from the Si substrate normal, was clearly visible in SEM. Films having C-axis inclination angles up to 45 deg. and thicknesses up to 10 microns have been obtained.

Descriptors :   *Piezoelectric materials, *Films, *Acoustic resonators, Fabrication, Sputtering, Zinc oxides, Aluminum compounds, Molecular structure, Orientation(Direction)

Distribution Statement : APPROVED FOR PUBLIC RELEASE