Abstract: A microwave filter made of acoustically coupled, bulk wave acoustic resonators. The resonators utilize piezoelectric materials sandwiched between conducting electrodes. Layers of material that intervene between the resonators control the amount of acoustic coupling between the resonators and the amount of coupling is selected to obtain desired filter characteristics. The resonators and the intervening layers may be supported upon a substrate by means of a series of layers of material that function as an acoustic mirror or reflector.

Abstract: A method for fabricating patterned layers of a desired material in a desired, design pattern upon a substrate, which method may be used in circumstances where the removal of photo-resist material may not be used to lift-off undesired portions of the material from the substrate. The method uses copper or some other conducting material instead of the photo-resist material, Which copper or other conducting material may be removed by chemical processes to lift-off the undesired portions of material deposited upon the conducting material and substrate. The copper or other conducting material is fabricated upon the substrate so as to have a lip that overhangs and shadows the boundary of photo-resist material previously fabricated upon the substrate in the desired pattern.

Abstract: An improved piezoelectric resonator having multiple layers of material within each electrode of the resonator. One layer of material within each electrode is selected and used to increase the effective coupling coefficient between the piezoelectric layer of material in the resonator and the electric fields resulting from the voltages applied to the electrodes. The second layer of material within each electrode is selected and used to decrease the electrical losses within the electrodes.

Abstract: A interdigital, slow-wave coplanar transmission line resonator utilizing a coupler. Sections of interdigital, slow-wave coplanar transmission lines having lengths of an integral number of quarter waves act as resonators. In one embodiment shorted transmission lines proximately located to the resonators electromagnetically coupled to the resonators to provide input and output ports to the resonators. In another embodiment, transmission lines are connected by taps to the resonators to provide input and output ports.

Abstract: A thin-film piezoelectric resonator and method of fabrication that includes a barrier layer of material between the underlying electrode and a layer of piezoelectric material. For example, in a resonator that uses zinc oxide for the layer of piezoelectric material, a barrier layer of aluminum nitride is deposited upon an underlying aluminum electrode to protect the aluminum electrode from oxidation or structural deformation during the subsequent deposition of the piezoelectric layer of zinc oxide. The barrier layer of aluminum nitride is deposited in a manner so as to provide a substrate having a substantial degree of uniformity of crystal orientation upon which the layer of piezoelectric material may then be deposited in a manner such that the piezoelectric layer will, itself, also have a substantial degree of uniformity in the orientations of its crystals.

Abstract: A chip-scale sized package for acoustic wave devices, acoustic resonators and similar acoustic devices located upon, or fabricated upon, or as part of, a die. The package includes a lid that is bonded to the die by a strip of solder or other bonding material so as to leave a space between the lid and that portion of the die that acoustically deforms or vibrates. The upper surface of the lid includes electrical connectors that are electrically connected via plated through holes or other means to electrical connectors, or pads on the lower surface of the lid, which pads, in turn, are electrically connected by solder or other electrically conducting material to electrical connectors to the device that are located upon the surface of the die.

Abstract: Piezoelectric resonators utilizing a differentially offset reflector. One or more piezoelectric resonators are supported upon a substrate by one or more intervening layers of material, which intervening layers of material act as a reflector. The reflector isolates the resonators from the substrate. A portion of one or more of the intervening layers of material includes a differential layer of material, which differential layer shifts the resonant frequencies of the resonators that overlie the differential layer as compared with the resonant frequencies of those resonators that do not overlie the differential layer of material.

Abstract: A microwave filter made of piezoelectric resonators fabricated in a monolithic device. Combinations of resonators connected in series and and parallel to each other are laid out in a symmetrical compact arrangement providing symmetrical and similar paths connecting the resonators together and to the ground. The symmetrical layout thus avoids differences in the connector inductances that otherwise would degrade filter performance.

Abstract: A method for fabricating piezoelectric resonators on a substrate such that the resonant frequency of one resonator is shifted by a small amount from another of the resonators. By means of differential fabrication of the electrodes, the thickness of the metal in an electrode for one resonator is increased relative to that of another resonator to obtain the shift in resonant frequency. The frequency of a single resonator also may be adjusted to a specific frequency by the addition of a differential layer of metal to one of the electrodes comprising the resonator. Mask alignment errors in the differential fabrication process cause non-uniformities in the thickness of the metal in the electrode which non-uniformities significantly degrade the performance of the resonator. The areas of non-uniform thickness of electrode that degrade the performance are removed in this process.

Abstract: A coplanar microwave transmission line on a substrate utilizes the interdigital capacitance between overlapped conducting fingers that extend from the conductors of the transmission line to reduce substantially the velocity of electromagnetic waves propagating on the transmission line without introducing prohibitive losses. The arrays of fingers extending from the conductors of the transmission line substantially overlap each other and are relatively densely packed. Layered substrates may be used to provide lower loss and a substantial reduction in velocity, which layered substrates may include layers of dielectric material located both above and below the conductors of the transmission line.

Abstract: A digital, differential signal processor for measuring, digitizing and storing a plurality of analog electrical potentials and for calculating selected potential differentials for display. Each analog, electrical potential is filtered and amplified in a signal conditioner and then its values at successive instants in time are converted to digital data by an analog to digital converter. The digital data that is output by the converter is stored for later recall. A computer calculates each selected differential potential by calculating the numerical difference between the digital data for the two potentials for which the differential is to be determined. The differential, as a function of time, may be displayed in real time or at a later time based upon the stored data. A multiplexer allows one analog to digital converter to process the signals output from a plurality of signal conditioners.

Abstract: A package for the storage and display of products such as video game cartridges and compact disks. The package consists of an elongated strip of transparent flexible plastic or similar material having a series of pockets or pouches attached to the the strip. The package may be hung from a hole at one end of the strip to display the contents of each of the pockets, the pockets all opening upwards towards the end of the strip from which the package is hung. The strip includes hinging portions between the pockets so that the cartridges or disks in the pockets can be folded together, in a zig-zag or accordion fashion to form a compact stack.

Abstract: A sailboat mast constructed of two extruded mast sections joined together by two joining sections. The joining sections have either wedge-shaped surfaces or wedge-shaped openings along their edges which mate with wedge-shaped openings or wedge-shaped surfaces at the edges of the mast sections. The mast sections and the joining sections are held together by a thin layer of glue located on the mating, wedge-shaped surfaces. Because of the wedge shapes, when the glue is applied and the mast sections and the joining sections are pressed together, the glue squeezes into a thin, uniform layer which provides a strong joint.

Abstract: A sailboat mast constructed of two extruded mast sections joined together by two joining sections. The joining sections have wedge-shaped surfaces along their edges which mate with wedge-shaped openings at the edges of the mast sections. The mast sections and the joining sections are held together by a thin layer of glue located on the mating, wedge-shaped surfaces. Because of the wedge shapes, when the glue is applied and the mast sections and the joining sections are pressed together, the glue squeezes into a thin, uniform layer which provides a strong joint.