Surface acoustic wave device
Abstract
Abstract A surface acoustic wave device has been developed, such as a surface acoustic wave filter in which a plurality of electroacoustic interdigital electrodes are formed, as thin films made principally of aluminum, on the surface of a Li 2 B 4 O 7 single crystal substrate and a surface acoustic wave resonator, in which a plurality of electroacoustic interdigital electrodes and grating reflectors for reflecting the surface acoustic wave are formed, as thin films made principally of aluminum, on the surface of a Li 2 B 4 O 7 single crystal substrate. Here, a cut angle, at which the substrate is cut from the Li 2 B 4 O 7 single crystal, and the propagation direction of the surface acoustic wave are so set that, when the Eulerian angle representation is (90°±λ, 90°±μ, 90°±θ), λ=38° to 52°, μ=0° to 5° and θ=0° to 10°, whereby the TCD of the surface acoustic wave device is below ±5 ppm/°C. and coupling coefficient K 2 is about 1.0%, and the propagation speed suffers almost no angular dependence.
Inventors
- 👤 Hitoshi Suzuki
- 👤 Yasuo Ebata
- 👤 Sadao Matsumura
- 👤 Jisaburo Ushizawa
Bibliographic Details
Claims Analysis
Total Claims: 9References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 1994-06-08 | 1994-12-08 | 1995-06-09 | $3760.00 | Window Closed / Lapsed |
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