A filter integrated circuit, including an acoustic wave filter chip and a matching circuit, is provided. The acoustic wave filter chip is covered upon a substrate. The matching circuit is disposed on the substrate to provide matching impedance to the acoustic wave filter chip. A first pad and a second pad of the matching circuit are respectively connected to a first signal terminal and a second signal terminal of the acoustic wave filter chip. First terminals of a first coil inductor and a second coil inductor of the matching circuit are respectively connected to the first pad and the second pad of the substrate. The first coil inductor is adjacent to the second coil inductor, so that mutual inductance and parasitic capacitance are formed, so that the matching circuit and the acoustic wave filter chip jointly generate a transmission zero point located in a triple fundamental frequency range.

A filter integrated circuit, including an acoustic wave filter chip and a matching circuit, is provided. The acoustic wave filter chip is covered upon a substrate. The matching circuit is disposed on the substrate to provide matching impedance to the acoustic wave filter chip. A first pad and a second pad of the matching circuit are respectively connected to a first signal terminal and a second signal terminal of the acoustic wave filter chip. First terminals of a first coil inductor and a second coil inductor of the matching circuit are respectively connected to the first pad and the second pad of the substrate. The first coil inductor is adjacent to the second coil inductor, so that mutual inductance and parasitic capacitance are formed, so that the matching circuit and the acoustic wave filter chip jointly generate a transmission zero point located in a triple fundamental frequency range.

A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.

A resonant member of a MEMS resonator oscillates in a mechanical resonance mode that produces non-uniform regional stresses such that a first level of mechanical stress in a first region of the resonant member is higher than a second level of mechanical stress in a second region of the resonant member. A plurality of openings within a surface of the resonant member are disposed more densely within the first region than the second region and at least partly filled with a compensating material that reduces temperature dependence of the resonant frequency corresponding to the mechanical resonance mode.

A bulk acoustic wave resonator having a central region, an outer region, and a raised frame region between the central region and the outer region is disclosed. The bulk acoustic wave resonator can include a piezoelectric layer and a top electrode over the piezoelectric layer. The top electrode is disposed at least in the central region, the outer region, and the raised frame region, the top electrode including a first layer and a second layer. A material of the first layer is different from the material of the second layer.

A bulk acoustic wave resonator having a central region, an outer region, and a raised frame region between the central region and the outer region is disclosed. The bulk acoustic wave resonator can include a piezoelectric layer and a top electrode over the piezoelectric layer. The top electrode is disposed at least in the central region, the outer region, and the raised frame region, the top electrode including a first layer and a second layer. A material of the first layer is different from the material of the second layer.

An acoustic resonator device and method thereof. The device includes a substrate member having an air cavity region. A piezoelectric layer is coupled to and configured overlying the substrate member and the air cavity region. The piezoelectric layer is configured to be characterized by an x-ray rocking curve Full Width at Half Maximum (FWHM) ranging from 0 degrees to 2 degrees. A top electrode is coupled to and configured overlying the piezoelectric layer, while a bottom electrode coupled to and configured underlying the piezoelectric layer within the air cavity region. The configuration of the materials of the piezoelectric layer and the substrate member to achieve the specific FWHM range improves a power handling capability characteristic and a power durability characteristic.

An acoustic resonator device and method thereof. The device includes a substrate member having an air cavity region. A piezoelectric layer is coupled to and configured overlying the substrate member and the air cavity region. The piezoelectric layer is configured to be characterized by an x-ray rocking curve Full Width at Half Maximum (FWHM) ranging from 0 degrees to 2 degrees. A top electrode is coupled to and configured overlying the piezoelectric layer, while a bottom electrode coupled to and configured underlying the piezoelectric layer within the air cavity region. The configuration of the materials of the piezoelectric layer and the substrate member to achieve the specific FWHM range improves a power handling capability characteristic and a power durability characteristic.

A temperature compensated oscillation circuit includes an oscillation circuit that oscillates a resonator, a fractional N-PLL circuit that multiplies frequency of an oscillation signal which is output by the oscillation circuit, on the basis of a frequency division ratio which is input, a temperature measurement unit that measures temperature, and a storage unit that stores a temperature correction table for correcting frequency temperature characteristics of the oscillation signal, in which the frequency division ratio of the fractional N-PLL circuit is set on the basis of a measurement value obtained by the temperature measurement unit and the temperature correction table.

A temperature compensated oscillation circuit includes an oscillation circuit that oscillates a resonator, a fractional N-PLL circuit that multiplies frequency of an oscillation signal which is output by the oscillation circuit, on the basis of a frequency division ratio which is input, a temperature measurement unit that measures temperature, and a storage unit that stores a temperature correction table for correcting frequency temperature characteristics of the oscillation signal, in which the frequency division ratio of the fractional N-PLL circuit is set on the basis of a measurement value obtained by the temperature measurement unit and the temperature correction table.