Abstract:
An acoustic resonator includes a substrate, a first electrode, a layer of piezoelectric material, a second electrode, and a recessed region. The substrate has a first surface. The first electrode is adjacent the first surface of the substrate. The layer of piezoelectric material is adjacent the first electrode. The second electrode is adjacent the layer of piezoelectric material. The second electrode has a second electrode perimeter that is shaped as a polygon. The recessed region is adjacent the second electrode. The recessed region has a shape defining a recessed region perimeter. The recessed region perimeter is recessed relative to the second electrode perimeter.
Abstract:
A magnetron with mechanisms for smoothly and continuously adjusting a DC power applied to its targets to compensate for the changes in the sputtering characteristics of the targets that occur with target aging. A magnetron according to the present teachings includes a set of concentric targets for sputtering a film onto a wafer in response to an AC power and a DC power applied to the targets and a power controller that adjusts the DC power. The adjustments to the DC power enable the magnetron to maintain uniformity in the thicknesses of films formed with the magnetron throughout the life of its targets.
Abstract:
In an array of acoustic resonators, the resonant frequencies of the resonators are adjusted and stabilized in order to achieve target frequency responses for the array. The method of adjusting is achieved by intentionally inducing oxidation at an elevated temperature. Thermal oxidation grows a molybdenum oxide layer on the surface of the top electrode of an electrode-piezoelectric stack, thereby increasing the relative thickness of the electrode layer to the piezoelectric layer. In one embodiment, the resonant frequency of an FBAR is adjusted downwardly as the top electrode layer increases relative to the piezoelectric layer. In another embodiment, the method of stabilizing is achieved by intentionally inducing oxidation at an elevated temperature.
Abstract:
In an array of acoustic resonators, the effective coupling coefficient of first and second filters are individually tailored in order to achieve desired frequency responses. In a duplexer embodiment, the effective coupling coefficient of a transmit band-pass filter is lower than the effective coupling coefficient of a receive band-pass filter of the same duplexer. In one embodiment, the tailoring of the coefficients is achieved by varying the ratio of the thickness of a piezoelectric layer to the total thickness of electrode layers. For example, the total thickness of the electrode layers of the transmit filter may be in the range of 1.2 to 2.8 times the total thickness of the electrode layers of the receive filter. In another embodiment, the coefficient tailoring is achieved by forming a capacitor in parallel with an acoustic resonator within the filter for which the effective coupling coefficient is to be degraded. Preferably, the capacitor is formed of the same materials used to fabricate a film bulk acoustic resonator (FBAR). The capacitor may be mass loaded to change its frequency by depositing a metal layer on the capacitor. Alternatively, the mass loading may be provided by forming the capacitor directly on a substrate.
Abstract:
A bulk acoustic wave device that provides a high spectral purity, high Q, resonator in the radio frequency and microwave frequency ranges. Such resonators may be coupled together to form filters or other frequency selective devices. The bulk acoustical wave filter is constructed from a piezoelectric (PZ) material having a first surface and a second surface and first and second electrodes. The first electrode includes an electrically conducting layer on the first surface, and the second electrode includes an electrically conducting layer on the second surface. The first electrode overlies at least a portion of the second electrode, the portion of the first electrode that overlies the second electrode has a periphery which is a non-rectangular, irregular polygon. In the preferred embodiment of the present invention, the periphery is a three-sided, four-sided, or n-sided irregular polygon in which no two sides are parallel to one another.
Abstract:
An acoustical resonator comprising top and bottom electrodes that sandwich a PZ layer. The resonance frequency of the acoustical resonator may be adjusted after fabrication by utilizing heating elements included in the acoustical resonator and/or by adjusting the thickness of a tuning layer. In the preferred embodiment of the present invention, the electrodes comprise Mo layers. One embodiment of the present invention is constructed on a Si.sub.3 N.sub.4 membrane. A second embodiment of the present invention is constructed such that it is suspended over a substrate on metallic columns. In the preferred embodiment of the present invention, the electrodes are deposited by a method that minimizes the stress in the electrodes.
Abstract translation:包括夹着PZ层的顶部和底部电极的声学谐振器。 可以通过利用声谐振器中包含的加热元件和/或通过调节调谐层的厚度来调整声学谐振器的共振频率。 在本发明的优选实施例中,电极包括Mo层。 本发明的一个实施方案构造在Si 3 N 4膜上。 本发明的第二实施例构造成使得其悬挂在金属柱上的基板上。 在本发明的优选实施例中,通过使电极中的应力最小化的方法来沉积电极。
Abstract:
A method for making metal/ceramic superconductor thick film structures including the steps of preparing a silver/superconductor ink, applying the ink to a substrate, evaporating the ink's binder, decomposing a silver compound in the residue to coat the superconductor grains, sintering the coated superconductor grains, and oxygenating the superconductor grains through the silver coating. The resultant inter-granular silver increases the critical current and mechanical strength of the superconductor.
Abstract:
A method for making metal/ceramic superconductor thick film structures including the steps of preparing a silver/superconductor ink, applying the ink to a substrate, evaporating the ink's binder, decomposing a silver compound in the residue to coat the superconductor grains, sintering the coated superconductor grains, and oxygenating the superconductor grains through the silver coating. The resultant inter-granular silver increases the critical current and mechanical strength of the superconductor.
Abstract:
A superconducting power distribution structure for integrated circuits characterized by a support member and a relatively thin superconducting capacitor member. Vias extending through the support member and the capacitor member couple power and ground plates of the capacitor member to power and ground traces on the circuit board. The vias are solder-bump connected to an integrated circuit chip, and the entire chip is cryogenically cooled to cause the plates of the capacitor to superconduct. The superconducting capacitor provides a large reservoir of charge to the integrated circuit chip through minimal inductance and with minimal voltage drop across its power plane.
Abstract:
An acoustic resonator structure comprises a substrate having a trench, a conductive pattern formed in the trench, a pillar formed within the trench, and an acoustic resonator supported at a central location by the pillar and suspended over the trench.