초록

Disclosed embodiments include a surface acoustic wave device having electrode period, electrode width, and/or ratio of electrode width to electrode period varied in a prescribed manner.

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1. A surface acoustic wave (SAW) device comprising: a substrate including lithium niobate (LiNbO3) and configured to provide a propagation of an acoustic wave;one or more resonators formed by a plurality of electrodes on a surface of the substrate, wherein the plurality of electrodes have individual

1. A surface acoustic wave (SAW) device comprising: a substrate including lithium niobate (LiNbO3) and configured to provide a propagation of an acoustic wave;one or more resonators formed by a plurality of electrodes on a surface of the substrate, wherein the plurality of electrodes have individual widths and are arranged with a plurality of different electrode periods with each of the plurality of different electrode periods being associated with a respective ratio of electrode width to electrode period; anda dielectric overcoat disposed between and over the plurality of electrodes, wherein the ratio of the electrode width to the electrode period is provided by:a/p=a_ref/p_ref+m*(p/p_ref−1);where a is the electrode width, p is the electrode period, m is a slope value between approximately 0.4 and 1.0, p_ref is value between a smallest electrode period (p_min) of the SAW device and a largest electrode period (p_max) of the SAW device, and a_ref/p_ref is a value between a_max/p_max and a_min/p_min, where a_max is a largest electrode width of the SAW device and a_min is a smallest electrode width of the SAW device. 2. The SAW device of claim 1, wherein m is approximately 0.5. 3. The SAW device of claim 1, wherein the substrate has an electromechanical coupling factor that is greater than approximately five percent. 4. The SAW device of claim 1, wherein the dielectric overcoat comprises silicon oxide (SiOx) and has a positive temperature coefficient of frequency (TCF) and a thickness, measured from a top surface of the plurality of electrodes to a top surface of the dielectric overcoat, that is greater than a thickness of the plurality of electrodes. 5. The SAW device of claim 4, wherein the ratio of the electrode width to electrode period is further based on a ratio of the thickness of the dielectric overcoat to the thickness of the plurality of electrodes. 6. The SAW device of claim 4, wherein the thickness of the dielectric overcoat is less than approximately three times the thickness of the plurality of electrodes. 7. The SAW device of claim 4, wherein the thickness of the dielectric overcoat is within a range from about twenty percent of the electrode period to about eighty percent of the electrode period. 8. The SAW device of claim 1, wherein the plurality of different electrode periods includes at least three different electrode periods with each associated with a respective ratio of electrode width to period. 9. The SAW device of claim 1, wherein a mass of individual electrodes is primarily provided by copper included in the individual electrodes. 10. The SAW device of claim 1, wherein an individual electrode has a thickness within a range from about ten to forty percent of a period associated with the individual electrode. 11. The SAW device of claim 1, wherein the substrate is configured to provide a propagation of a non-leaky acoustic wave and has an orientation defined by Euler angles (λ±3 degrees, μ, θ±3 degrees), with angle μ=μ′−90 degrees, where μ′ is a Y rotation of the substrate and ranges from about 130 degrees to about 170 degrees. 12. The SAW device of claim 1, wherein the ratios of electrode width to electrode periods are between approximately forty percent and sixty percent. 13. A surface acoustic wave (SAW) device comprising: a substrate including lithium niobate (LiNbO3) and configured to provide a propagation of an acoustic wave;a first resonator including a first plurality of electrodes having widths (a1) and being arranged in a first pattern that includes a first electrode period (p1);a second resonator including a second plurality of electrodes having widths (a2) and arranged in a second pattern that includes a second electrode period (p2), wherein p1(p2−a2)/p2. 14. The SAW device of claim 13, further comprising: a dielectric overcoat disposed between and over the first and second plurality of electrodes and including silicon oxide (SiOx), a positive temperature coefficient of frequency (TCF), and a thickness, measured from a top surface of the first and second plurality of electrodes to a top surface of the dielectric overcoat, that is greater than a thickness of the first and second plurality of electrodes. 15. The SAW device of claim 14, wherein the thickness of the dielectric overcoat is less than approximately three times the thickness of the first and second plurality of electrodes. 16. The SAW device of claim 14, wherein the thickness of the dielectric overcoat is within a range from about twenty percent of a reference electrode period to about eighty percent of a reference electrode period, wherein the reference electrode period is based on the first period or the second period.