Abstract:
An acoustic resonator device includes a composite first electrode on a substrate, a piezoelectric layer on the composite electrode, and a second electrode on the piezoelectric layer. The first electrode includes a buried temperature compensating layer having a positive temperature coefficient. The piezoelectric layer has a negative temperature coefficient, and thus the positive temperature coefficient of the temperature compensating layer offsets at least a portion of the negative temperature coefficient of the piezoelectric layer.
Abstract:
A self-calibrating temperature compensated oscillator includes a monolithic structure having a first resonator, a second resonator, and a heating element to heat the first and second resonators. The temperature coefficient of the second resonator is substantially greater than the temperature coefficient of the first resonator. A first oscillator circuit operates with the first resonator and outputs a first oscillator output signal having a first oscillating frequency. A second oscillator circuit operates with the second resonator and outputs a second oscillator output signal having a second oscillating frequency. A temperature determining circuit determines the temperature of the first resonator using the second oscillating frequency. A temperature compensator provides a control signal to the first oscillator in response to the determined temperature to adjust the first oscillating frequency and maintain it at a desired operating frequency.
Abstract:
A self-calibrating temperature compensated oscillator includes a monolithic structure having a first resonator, a second resonator, and a heating element to heat the first and second resonators. The temperature coefficient of the second resonator is substantially greater than the temperature coefficient of the first resonator. A first oscillator circuit operates with the first resonator and outputs a first oscillator output signal having a first oscillating frequency. A second oscillator circuit operates with the second resonator and outputs a second oscillator output signal having a second oscillating frequency. A temperature determining circuit determines the temperature of the first resonator using the second oscillating frequency. A temperature compensator provides a control signal to the first oscillator in response to the determined temperature to adjust the first oscillating frequency and maintain it at a desired operating frequency.
Abstract:
An oscillator including a high tone bulk acoustic resonator (HBAR), a film bulk acoustic resonator (FBAR) filter and a method of fabrication are described.
Abstract:
An acoustic resonator device includes a composite first electrode on a substrate, a piezoelectric layer on the composite electrode, and a second electrode on the piezoelectric layer. The first electrode includes a buried temperature compensating layer having a positive temperature coefficient. The piezoelectric layer has a negative temperature coefficient, and thus the positive temperature coefficient of the temperature compensating layer offsets at least a portion of the negative temperature coefficient of the piezoelectric layer.
Abstract:
An oscillator comprises a substrate and a high tone bulk acoustic resonator (HBAR), which includes a portion of the substrate. The oscillator also comprises a film bulk acoustic resonator (FBAR) filter disposed over the substrate. The filter comprises a plurality of FBAR devices. The oscillator also comprises a plurality of acoustic isolators disposed in the substrate, wherein one of the isolators is disposed beneath each of the FBAR devices. A method of fabricating an oscillator is also disclosed.
Abstract:
An acoustic resonator device includes an annular acoustic resonator, a heater coil and a heat sensor. The annular acoustic resonator is positioned over a trench formed in a substrate of the acoustic resonator device. The heater coil is disposed around a perimeter of the annular acoustic resonator, the heater coil including a resistor configured to receive a heater current. The heat sensor is configured to adjust the heater current in response to a temperature of the heater coil.
Abstract:
Disclosed is an acoustic resonator that includes a substrate, a first electrode, a layer of piezoelectric material, a second electrode, and an alternating frame region. The first electrode is adjacent the substrate, and the first electrode has an outer perimeter. The piezoelectric layer is adjacent the first electrode. The second electrode is adjacent the piezoelectric layer and the second electrode has an outer perimeter. The alternating frame region is on one of the first and second electrodes.
Abstract:
A method for fabricating a resonator, and in particular, a thin film bulk acoustic resonator (FBAR), and a resonator embodying the method are disclosed. An FBAR is fabricated on a substrate by reducing mass from a top electrode layer. For a substrate having multiple resonators, mass is reduced from only selected resonator to provide resonators having different resonance frequencies on the same substrate.