Highly textured growth of AlN films on sapphire by magnetron sputtering for high temperature surface acoustic wave applications

Journal Article · Tue Mar 15 00:00:00 EDT 2011 · Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films

DOI:https://doi.org/10.1116/1.3551604· OSTI ID:22054022

Aubert, T; Assouar, M B; Legrani, O; Elmazria, O; Tiusan, C; Robert, S ^[1]

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1. Institut Jean Lamour, UMR 7198, Nancy University-CNRS, BP 70239, Bd des Aiguillettes, 54506 Vandoeuvre Cedex (France)

Piezoelectric aluminum nitride films were deposited onto 3 in. [0001] sapphire substrates by reactive magnetron sputtering to explore the possibility of making highly (002)-textured AlN films to be used in surface acoustic wave (SAW) devices for high temperature applications. The synthesized films, typically 1 {mu}m thick, exhibited a columnar microstructure and a high c-axis texture. The relationship between the microstructures and process conditions was examined by x-ray diffraction (XRD), transmission electron microscopy, and atomic force microscopy analyses. The authors found that highly (002)-textured AlN films with a full width at half maximum of the rocking curve of less than 0.3 deg. can be achieved under high nitrogen concentration and moderate growth temperature, i.e., 250 deg. C. The phi-scan XRD reveals the high in-plane texture of deposited AlN films. The SAW devices, based on the optimized AlN films on sapphire substrate, were characterized before and after an air annealing process at 800 deg. C for 90 min. The frequency response, recorded after the annealing process, confirmed that the thin films were still strong in a high temperature environment and that they had retained their piezoelectric properties.

• OSTI ID: 22054022
• Journal Information: Journal of Vacuum Science and Technology. A, International Journal Devoted to Vacuum, Surfaces, and Films, Vol. 29, Issue 2; Other Information: (c) 2011 American Vacuum Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1553-1813
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM NITRIDES
ANNEALING
ATOMIC FORCE MICROSCOPY
CRYSTAL GROWTH
DEPOSITION
MAGNETRONS
MICROSTRUCTURE
NITROGEN
PIEZOELECTRICITY
SAPPHIRE
SPUTTERING
TEMPERATURE RANGE 0400-1000 K
THIN FILMS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION