Abstract: A process for configuring a thin film resonator to advantageously shape a desired acoustic mode of the resonator such that the electrical and acoustic performance of the resonator is enhanced. As a result of the contouring or shaping, a minimum amount of acoustic energy occurs near the edge of the resonator, from which energy may leak or at which undesired waves may be created by a desired mode. The process is used during batch-fabrication of thin-film resonators which are used in high frequency RF filtering or frequency control applications. Utilizing photolithography, the shaping can be achieved in a manner derived from the known methods used to manufacture lens arrays. Using the process, the lateral motion of acoustic waves within the resonator may be controlled and the acoustic energy of the sound wave positioned at a desired location within the resonator.

Abstract: A quality-assurance method is described that is useful in the fabrication of piezoelectric films of electronic devices, particularly resonators for use in RF filters. For example, the method comprises determining the surface roughness of an insulating layer on which the piezoelectric film is to be deposited and achieving a surface roughness for the insulating layer that is sufficiently low to achieve the high-quality piezoelectric film. According to one aspect of the invention, the low surface roughness for the insulating layer is achieved with use of a rotating magnet magnetron system for improving the uniformity of the deposited layer. According to other aspects of the invention, the high-quality piezoelectric film is assured by optimizing deposition parameters including determination of a “cross-over point” for reactive gas flow and/or monitoring and correcting for the surface roughness of the insulating layer pre-fabrication of the piezoelectric film.

Abstract: The present invention is a method for adjusting the resonant frequency of a mechanical resonator whose frequency is dependent on the overall resonator thickness. Alternating selective etching is used to remove distinct adjustment layers from a top electrode. One of the electrodes is structured with a plurality of stacked adjustment layers, each of which has distinct etching properties from any adjacent adjustment layers. Also as part of the same invention is a resonator structure in which at least one electrode has a plurality of stacked layers of a material having different etching properties from any adjacent adjustment layers, and each layer has a thickness corresponding to a calculated frequency increment in the resonant frequency of the resonator.

Abstract: The present invention is a method for adjusting the resonant frequency of a mechanical resonator whose frequency is dependent on the overall resonator thickness. Alternating selective etching is used to remove distinct adjustment layers from a top electrode. One of the electrodes is structured with a plurality of stacked adjustment layers, each of which has distinct etching properties from any adjacent adjustment layers. Also as part of the same invention is a resonator structure in which at least one electrode has a plurality of stacked layers of a material having different etching properties from any adjacent adjustment layers, and each layer has a thickness corresponding to a calculated frequency increment in the resonant frequency of the resonator.

Abstract: A TFR ladder filter which may yield less degradation in the stopband near the passband edges than conventionally grounded TFR ladder filters. Each of the plurality of shunt-coupled TFR elements of the ladder filter has its own dedicated ground path which is to connected to a final ground external from the ladder filter, so that each shunt-coupled TFR element is individually isolated from one another. Particularly, each shunt-coupled TFR element has a corresponding wirebond to individually connect its top metal ground electrode to a final external ground of a carrier or package on which the die encompassing the TFR ladder filter rests.

Abstract: This invention relates to a method and apparatus for imaging acoustic fields in high-frequency acoustic resonators. More particularly, the invention is directed to a scanning RF mode microscope system that detects and monitors vibration of high frequency resonators that vibrate in the frequency range of approximately 1 MHz to 20 GHz. The system then maps with sub-Angstrom resolution vibration modes of such devices and obtains quantitative measurements of the piezoelectric properties of the materials.

Abstract: The present invention is a method for adjusting different resonant frequencies of a plurality of mechanical resonators formed on a common substrate, in a case where the resonant frequencies of the resonators are a function of each resonator thickness. According to this method the resonators are each formed with an etchable top electrode layer which includes a material having different etching properties as a topmost layer for each of the resonators having different resonant frequencies. By selectively etching these etchable layers one at a time in the presence of the others, one may adjust the resonant frequencies of each of the resonators without need to mask the resonators during the etching process. Associated with this method there is a resonator structure having a top electrode structure having a topmost layer having different etching characteristics for different resonators.

Abstract: An article comprising a multi-port variable capacitor is disclosed. In one embodiment, a movable plate is suspended above at least a first and a second, fixed, electrically-isolated electrode. The first electrode is electrically connected to a bias supply, and the second electrode is electrically connected to an AC signal-carrying line. As bias is applied across the first electrode and the movable plate, an electrostatic attraction is developed therebetween that causes the movable plate to move downwardly towards the first electrode. The capacitance of the variable capacitor increases as the separation distance between the movable plate and the fixed electrodes decreases. Unlike conventional variable capacitors, in the present multi-port variable capacitors, the bias (delivered via the first electrode) and the signal (delivered via the second electrode) are electrically isolated from one another. As such, the bias (DC) and signal (AC) paths are advantageously electrically isolated.

Abstract: An article for directing optical signals among optical waveguides is disclosed. The article comprises a plurality of mirror elements that are mechanically and electrically interconnected to form a reflective surface. The reflective surface is deformable upon application of a voltage. Optical signals delivered from a source waveguide may be directed to different destination waveguides as the reflective surface is deformed. The plurality of mirror elements is actuated by a single actuator.

Abstract: An article comprising a micro-machined, passively self-assembling inductor is disclosed. The inductor is fabricated using MEMS technology and advantageously utilizes materials compatible with CMOS such that inductor is monolithically integrable with a CMOS chip. The inductor includes passive self-assembly means by which the inductor loop is moved away from an underlying substrate, typically silicon, in the final steps of inductor assembly. Such passive self-assembly does not require separate actuation or monitoring steps.

Abstract: A switching element according to this invention comprises a photostrictive member. Exposing the member to control light results in a dimensional change in the material. This change is utilized for changing the relative position between an optical fiber and another element, exemplarily a further fiber, a corrugated member, or a mirror, such that signal radiation is directed to a predetermined output port. A variety of exemplary switching elements are disclosed, including interferometric, beam-steering, evanescent field and mode conversion switching elements. Disclosed are also optical communication systems that utilize such switching elements, including passive optical networks.

Abstract: Sonoluminescence is an off-equilibrium phenomenon in which the energy of a resonant sound wave in a liquid is highly concentrated so as to generate flashes of light. The conversion of sound to light represents an energy amplification of eleven orders of magnitude. The flashes which occur once per cycle of the audible or ultrasonic sound fields can be comprised of over one million photons and last for less 100 picoseconds. The emission displays a clocklike synchronicity; the jitter in time between consecutive flashes is less than fifty picoseconds. The emission is blue to the eye and has a broadband spectrum increasing from 700 nanometers to 200 nanometers. The peak power is about 100 milliWatts. The initial stage of the energy focusing is effected by the nonlinear oscillations of a gas bubble trapped in the liquid. For sufficiently high drive pressures an imploding shock wave is launched into the gas by the collapsing bubble.