Abstract: A HACT device employing a thin-film overlay of a more strongly piezoelectric material can operate as a delay line and as a tapped delay line, or transversal filter, while requiring less total power for the SAW clock signal. The increased electrical potential per unit total SAW power thus realized facilitates coupling between the total SAW energy and the mobile charge carriers. Some materials systems, such as a GaAs substrate and a ZnO thin-film overlay, will require an intervening thin-film dielectric layer in between the HACT substrate and epitaxial layers and the thin-film piezoelectric overlay. This may be necessitated by chemical, semiconductor device processing, or adhesion incompatibilities between the substrate material and the thin-film overlay material.

Abstract: An ionization gas analyzer system includes an ionization chamber including ionization electrodes contained therein. The ionization chamber contains a test gas or gas mixture. A high voltage generator is coupled to the electrodes and provides variable high voltage pulses to the ionization electrodes. An ionization voltage analyzer is coupled to the ionization chamber and receives ionization voltage information from the plurality of ionization electrodes in response to the variable high voltages pulses. The ionization voltage analyzer produces a gas code identifier in response to the plurality of ionization voltages by defining a code based on which of the ionization voltages exceed an arbitrarily established reference level ionization voltage. A single ionization electrode system can be used to determine a concentration of a particular gas.

Abstract: A radio frequency apparatus desirably includes at least one microelectronic device comprising a substrate including the at least one microelectronic device and a package base for mounting the microelectronic device. The package base includes external interconnections coupled to internal interconnections and an adhesive affixing the substrate to the package base. The adhesive is disposed along a first axis of the substrate. The internal interconnections are coupled to the microelectronic device. A lid is sealed to the package base. The lid seals the microelectronic device.

Abstract: A reflector arrangement for an acoustic wave device comprises an acoustic wave propagating substrate, reflection elements having at least two different widths separated by at least one gap breadth disposed on the acoustic wave propagating substrate. The at least two different widths enhance reflected waves produced by the propagating acoustic wave in such a fashion as to achieve a total acoustic reflectivity which is independent of variations in width of the reflection elements.

Abstract: A method for making a light weight circuit module includes steps of providing a substrate, drilling through holes in the substrate and plating the through holes with a metal. The substrate is a rigid planar substrate and having metallization on both sides. The method also includes steps of drilling through holes in the substrate and plating the through holes with a metal. The method also includes steps of preparing a patterned photoresist layer on at least one of the two sides, etching the metallization on the at least one side in accordance with the patterned photoresist layer, drilling support holes, filling the support holes with a material chemically distinct from the substrate, stripping the patterned photoresist layer from the at least one side and chemically removing the substrate from the metallization.

Abstract: An acoustic wave filtering apparatus includes an acoustic wave propagating substrate for supporting propagation of acoustic waves and a plurality of acoustic wave filters for filtering an electrical signal. Each of said plurality further comprises an input for supplying electrical input signals, an input unidirectional acoustic wave transducer for converting electrical signal energy into acoustic energy, an output unidirectional acoustic wave transducer for converting acoustic signals to electrical signals, and an output for combining and delivering electrical output signals to external electrical apparatus.

Abstract: A reflector arrangement for an acoustic wave device comprises an acoustic wave propagating substrate, reflection elements having at least two different widths separated by at least one gap breadth disposed on the acoustic wave propagating substrate. The at least two different widths enhance reflected waves produced by the propagating acoustic wave in such a fashion to as to achieve a total acoustic reflectivity which is independent of variations in width of the reflection elements.

Abstract: In a radio transceiver (100), an IF stage (110) is formed on a single substrate. A balanced or image rejection mixer (204) having two pairs of inputs and a pair of outputs is integrated on an IC substrate (202). Disposed on the IC substrate are SAW transformers (210, 212 and 214) which provide a desired phase transformation. The SAW transformers comprise piezoelectric layers (228) and metallization layers (230) which are suitably patterned to provide the desired phase transformation and frequency selectivity.

Abstract: Surface acoustic wave devices (160) as well as other electronic devices, can be mounted into the sides of ceramic blocks (150) that comprise a ceramic block filter device. The surface acoustic wave device as mounted in the filter block does not require or displace volume that would be required to mount the surface acoustic wave devices in their own housings.

Abstract: A surface acoustic wave (SAW) device package for reducing insertion loss and direct RF feedthrough of the SAW device is disclosed. The package provides for extensive shielding of each of the input and output pads. The inputs and outputs to the SAW device are separated by maintaining the inputs on one surface of the substrate and the outputs on the opposite surface of the substrate. The SAW crystal substrate including the SAW devices is bonded to the package substrate and the package is hermetically sealed via a low-temperature glass seal or solder-type sealing, for example.

Abstract: An acoustic wave device comprises an acoustic wave transducer coupled to an acoustic wave propagating substrate. The acoustic wave transducer converts signal energy between electrical and acoustical forms. Acoustic reflectors are placed one on either side of the acoustic wave transducer. The acoustic reflectors are composed of acoustic reflection elements spaced approximately one wavelength apart, and provide enhanced acoustic acoustic reflections together with relaxed fabrication constraints.

Abstract: A method for microelectronic device encapsulation is described comprising steps of providing a microelectronic device (e.g., a surface acoustic wave device) having interconnection contacts disposed thereon and depositing a passivation layer over the microelectronic device and the interconnection contacts. The method further comprises steps of providing alternating current coupled electrodes positioned on the passivation layer and over the interconnection contacts, providing a base substrate (including pressure contact electrodes and vias) and bonding the base substrate to the microelectronic device with a bonding agent for providing a mechanical bond between the microelectronic device and the base and for providing a hermetically sealed environment for the microelectronic device. The method further comprises providing electrical coupling between the pressure contact electrodes and the alternating current coupled electrodes.

Abstract: An ACT (acoustic charge transport) filter comprises a plurality of SAW (surface acoustic wave) transducers and an interleaved filter bank coupled on either transversal side of the SAW transducer. Each interleaved filter bank comprises two filters, and the electrodes of the two filters are interleaved. Isolation between the interleaved electrodes is supplied by a meadering ground. The electrodes are apodized to facilitate weighted sampling of the delayed signal. Multiple frequency characteristics may be extracted from a single ACT filter by cascading the SAW transducer/interleaved filter bank combinations. Weighted sampling of the delayed signal may also be accomplished through weighted withdrawal of the ACT filter.

Abstract: A microelectronic device including a passivation layer disposed on the top surface has disposed on a portion of its surface a bonding agent. The resulting structure is inverted and sealed to a package base, forming a hermetically sealed cavity. This protects the microelectronic device from the environment. External electrical connection to other electronic apparatus is effected by means of conductors disposed on the package base surface. Alternating current (AC) capacitive coupling contacts allow electrical coupling to the microelectronic device and prevent violation of the integrity of the passivation layer. This method realizes compact microelectronics device packages which can be mass produced from entire microelectronic device substrates.

Abstract: A bipolar injector structure, similar to a common-base amplifier circuit, is described for use as a unidirectional injector of charge for a charge-transfer device input circuit. This injector structure acts to reduce the input impedance of such devices. A plurality of bipolar injector structures may be implemented on a single ACT device channel, and electrically connected in parallel, to effect a further reduction of input impedance and a further increase in device dynamic range. By employing an input contact structure which allows charge to be injected at more than one point along the length of the channel, without perturbing charge which was injected at some earlier time, a means for forming a transversal filter function can be realized at the input contact structure in addition to that which is achieved at the output contact structure, thus permitting improved ACT device selectivity when operated as a filter.

Abstract: A piezoelectric semiconductor device for greatly increasing the linear channel length and storage capacity of an acoustic charge transport (ACT) device. Synchronized surface acoustic wave devices are aligned approximately orthogonally to each other so that in an angular portion of the channel, the charge packets of an input signal are bent at approximately a 45.degree. angle. As a result, channel length and therefore storage capacity of the channel and ACT device are greatly increased. One embodiment is a 45.degree. angle spiral channel. Another embodiment is a serpentine channel with 45.degree. angle bends.

Abstract: An apparatus and method is disclosed for providing an optical waveguide that is placed in the same plane as the electrodes, thereby creating a more efficient electro optic interaction that requires less voltage to induce the desired effects on the waveguide. In addition, a superstrate is used to cover the waveguide having an index of refraction slightly less than the index of refraction of the waveguide which reduces the scattering loss inherent in the waveguide.

Abstract: Passivated and low scatter acoustic wave devices comprise surface acoustic wave (SAW) and shallow bulk acoustic wave (SBAW) devices having transducers composed of oxidizable metal and layers of metal oxide on conventional acoustic wave substrates. Passivated transducers are achieved by forming a layer of oxide on an existing transducer. The method may be used to passivate a device packaged in a non-oxidizable package with oxidizable wire leads, thus combining complete protection with efficient manufacturing operations. Low scatter SAW transducers are achieved by forming the transducer and the interstitial insulating layer from a single layer of oxidizable metal by means of masking and oxidation operations.

Abstract: A HACT device employing a thin-film overlay of a more strongly piezoelectric material can operate as a delay line and as a tapped delay line, or transversal filter, while requiring less total power for the SAW clock signal. The increased electrical potential per unit total SAW power thus realized facilitates coupling between the total SAW energy and the mobile charge carriers. Some materials systems, such as a GaAs substrate and a ZnO thin-film overlay, will require an intervening thin-film dielectric layer in between the HACT substrate and epitaxial layers and the thin-film piezoelectric overlay. This may be necessitated by chemical, semiconductor device processing, or adhesion incompatibilities between the substrate material and the thin-film overlay material.