Abstract: An acoustic wave device includes: a substrate; a lower electrode, an air gap being interposed between the lower electrode and the substrate; a piezoelectric film located on the lower electrode; and an upper electrode located on the piezoelectric film such that a resonance region where at least a part of the piezoelectric film is interposed between the upper electrode and the lower electrode is formed and the resonance region overlaps with the air gap in plan view, wherein a surface facing the substrate across the air gap of the lower electrode in a center region of the resonance region is positioned lower than a surface closer to the piezoelectric film of the substrate in an outside of the air gap in plan view.

Abstract: An acoustic wave device includes: a substrate; a lower electrode, an air gap being interposed between the lower electrode and the substrate; a piezoelectric film located on the lower electrode; and an upper electrode located on the piezoelectric film such that a resonance region where at least a part of the piezoelectric film is interposed between the upper electrode and the lower electrode is formed and the resonance region overlaps with the air gap in plan view, wherein a surface facing the substrate across the air gap of the lower electrode in a center region of the resonance region is positioned lower than a surface closer to the piezoelectric film of the substrate in an outside of the air gap in plan view.

Abstract: A surface acoustic wave device includes a SAW device chip mounted on a substrate, and a lid provided so as to cover the SAW device. A maximum thickness of a ceiling portion of the lid that does not face the SAW device chip is greater than that of another ceiling portion of the lid that faces the SAW device chip.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, at least one interdigital transducer (IDT) provided on the piezoelectric substrate, and a shield electrode provided on the piezoelectric substrate. The IDT has a first pattern on an edge that faces the shield electrode. The shield electrode has a second pattern on an edge so as to be evenly spaced apart from the first pattern.

Abstract: A surface acoustic wave (SAW) device includes a piezoelectric substrate, a first and a second interdigital transducers (IDT) provided thereon. The second IDT has a side that is substantially aligned with a corresponding side of the first IDT, and another side of the second IDT is arranged so that the second IDT may adjust a leaked wave caused resulting from by a power-flow angle of the piezoelectric substrate.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, a first and a second interdigital transducers (IDTs) provided on the piezoelectric substrate. The first IDT includes multiple tracks having different frequency characteristics that are connected in parallel. The second IDT includes a normalized electrode pattern. The frequency characteristic of the multiple tracks is asymmetric to a center frequency of the SAW filter, substantially flat in a passband when those of the multiple tracks are overlapped, or complementary in the passband. Thus, it is possible to provide the surface acoustic wave device having a high damping property.

Abstract: A filter includes a piezoelectric substrate, and interdigital transducers (IDTs) that are formed on the piezoelectric substrate. At least one of the IDTs has a main electrode finger pattern that is weighted. The IDT having the main electrode finger pattern also has a sub electrode finger pattern that is connected in parallel to the main electrode finger pattern, and generates a surface acoustic wave that cancels a surface acoustic wave caused by leakage electric fields generated in the main electrode finger pattern.

Abstract: A surface acoustic wave device includes: a substrate; a pair of reflection electrodes that are formed on the substrate; and drive electrodes that are interposed between the reflection electrodes. In this surface acoustic wave device, the pitches in each of the reflection electrodes vary according to a predetermined variation pattern. With this structure, the suppression on spurious signals and the shape factor (the sharpness of the cut-off region of the pass band) can be improved at the same time.

Abstract: A surface acoustic wave (SAW) device includes a piezoelectric substrate, a first and a second interdigital transducers (IDT) provided thereon. The second IDT has a side that is substantially aligned with a corresponding side of the first IDT, and another side of the second IDT is arranged so that the second IDT may adjust a leaked wave caused resulting from by a power-flow angle of the piezoelectric substrate.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, a first and a second interdigital transducers (IDTs) provided on the piezoelectric substrate. The first IDT includes multiple tracks having different frequency characteristics that are connected in parallel. The second IDT includes a normalized electrode pattern. The frequency characteristic of the multiple tracks is asymmetric to a center frequency of the SAW filter, substantially flat in a passband when those of the multiple tracks are overlapped, or complementary in the passband. Thus, it is possible to provide the surface acoustic wave device having a high damping property.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, at least one interdigital transducer (IDT) provided on the piezoelectric substrate, and a shield electrode provided on the piezoelectric substrate. The IDT has a first pattern on an edge that faces the shield electrode. The shield electrode has a second pattern on an edge so as to be evenly spaced apart from the first pattern.

Abstract: A filter includes a piezoelectric substrate, and interdigital transducers (IDTs) that are formed on the piezoelectric substrate. At least one of the IDTs has a main electrode finger pattern that is weighted. The IDT having the main electrode finger pattern also has a sub electrode finger pattern that is connected in parallel to the main electrode finger pattern, and generates a surface acoustic wave that cancels a surface acoustic wave caused by leakage electric fields generated in the main electrode finger pattern.

Abstract: A surface acoustic wave device includes: a substrate; a pair of reflection electrodes that are formed on the substrate; and drive electrodes that are interposed between the reflection electrodes. In this surface acoustic wave device, the pitches in each of the reflection electrodes vary according to a predetermined variation pattern. With this structure, the suppression on spurious signals and the shape factor (the sharpness of the cut-off region of the pass band) can be improved at the same time.