Abstract: A new type of acoustic wave which is nearly polarized in the shear horizontal direction, and which can propagate in thin elastic plates if the ratio h/.lambda. is less than about 3 where h is the plate thickness and .lambda. is the acoustic wavelength. Attractive properties of this quasi-SH wave include: (i) nearly nondispersive propagation, (ii) very large value of K.sup.2, the electromechanical coupling coefficient, and (iii) ability to propagate in contact with a liquid medium without suffering excessive attenuation. The nondispersive propagation and large value of K.sup.2 makes the wave attractive for use in signal processing and sensing devices. Further, the fact that the wave can propagate in contact with a liquid medium allows the wave to be used in sensors that have to operate in contact with a liquid medium.

Abstract: A surface acoustic wave filter includes a piezoelectric substrate. On the surface of the piezoelectric substrate, an input transducer and an output transducer are formed at a predetermined interval. The input transducer and the output transducer are respectively formed with a pair of IDT (interdigital electrode transducers) disposed oppositely. A pair of IDT which construct at least one transducer of the input transducer and the output transducer are formed on the piezoelectric substrate in the following manner. That is, a first impulse train is determined by inverse Fourier transformation of desired transmission characteristics (where, center frequency is f.sub.0 and surface wavelength is .sub.

Abstract: A surface acoustic wave device has a package and a surface acoustic wave element mounted therein face down. The package includes a side wall comprising linear inner side surfaces close to respective outer side surfaces of the surface acoustic wave element and recesses defined where the inner side surfaces of the side wall intersect at respective inner corners. When the surface acoustic wave element is inserted into the side wall along the inner side surfaces thereof, the corners of the surface acoustic wave element do not engage the side wall because of the recesses. Therefore, the outer side surfaces of the surface acoustic wave element may be positioned very closely to the inner side surfaces of the side wall. The surface acoustic wave device may be reduced in size, and the surface acoustic wave element may have input and output electrode pads and ground pads positioned highly accurately with respect to electrode pads on the bottom plate of the package.

Abstract: The highly-oriented diamond film is a diamond film formed by chemical vapor deposition, with at least 95% of its area consisting of either (100) or (111) crystal planes, and the differences {.DELTA..alpha., .DELTA..beta., .DELTA..gamma.} of the Euler angles {.alpha., .beta., .gamma.} between the adjacent crystals satisfying (.vertline..DELTA..alpha..vertline..ltoreq.1.degree., .vertline..DELTA..beta..vertline..ltoreq.1.degree. and .vertline..DELTA..gamma..vertline..ltoreq.1.degree.) simultaneously. Thus obtained highly-oriented diamond film has few grain boundaries and high carrier mobility. And the area of the diamond film can be large.

Abstract: A composite surface acoustic wave filter includes an interdigitated interdigital surface acoustic wave filter having input and output terminals. Two one-port surface acoustic wave resonators are electrically connected in series to the interdigitated interdigital surface acoustic wave filter respectively at the input and output terminals, the one-port surface acoustic wave resonators having antiresonant frequencies in a stop band that is close to and higher than the passband of the interdigitated interdigital surface acoustic wave filter. Two other one-port surface acoustic wave resonators are electrically connected parallel to the interdigitated interdigital surface acoustic wave filter, the one-port surface acoustic wave resonators having resonant frequencies in a stop band that is close to and lower than the passband of the interdigitated interdigital surface acoustic wave filter.

Abstract: A surface acoustic wave interdigital transducer of a filter includes split finger electrodes in pairs. To achieve a desired transfer characteristic that is either symmetrical or deliberately asymmetrical, a number of the pairs of the split finger electrodes are replaced by single finger electrodes.

Abstract: A surface wave filter element includes a portion on which elastic surface waves propagate. This portion includes a piezoelectric material, an amorphous boron layer or plate and IDT electrodes for inputting and outputting signals. The piezoelectric material is a film made of ZnO, LiNbO.sub.3 or LiTaO.sub.3 formed by sputtering, ion beam deposition or chemical vapor deposition. The amorphous boron layer or boron plate may be formed on a substrate made of an inorganic material. The boron material is formed using electron beam deposition, ion beam deposition or chemical vapor deposition.

Abstract: A waveguide for surface acoustic waves comprises a substrate for supporting propagation of surface acoustic waves along a direction at a substrate velocity and a dielectric structure disposed above the substrate along the propagation direction of the surface acoustic waves. The structure includes a central portion disposed along the propagation direction, first and second intermediate portions respectively disposed along each opposed side of the central portion along the propagation direction, and first and second outer portions respectively disposed along each outer side of the first and second intermediate portions along the propagation direction. The central, intermediate and outer portions each has first, second and third intrinsic surface acoustic wave propagation velocities along the propagation direction of the surface acoustic waves, respectively and the first velocity is intermediate of the second and third velocities.

Abstract: A motor includes two parts that are mobile one with respect to the other and have facing surfaces contacting each other. Progressive surface acoustic waves of the same direction are produced in each facing surface of each part. The relative speed or position of the parts is adjusted by acting on the relative frequency or phase of the progressive waves.

Abstract: A surface acoustic wave (SAW) device (300) comprising interdigital transducers (302, 304, 306) combined on acoustic tracks (308, 310). Resonant interdigital transducers (302, 304) are electrically and acoustically coupled in series on a common acoustic track (308) while anti resonant transducer (306) is electrically coupled to the series connection and located on the second acoustic track (310).

Abstract: Communication between an upstream point, such as a TV-source headend followed by a fiber optic line, and a number of downstream points, such as coaxial cable connected subscriber locations, is achieved by wavelength or frequency demultiplexing a spectrum of downstream radio-frequency signals with a surface-acoustic-wave (SAW) demultiplexer-multiplexer and distributing the demultiplexed signals to the downstream points, for example through the cables.

Abstract: A chemical sensor includes a piezoelectric support (1) capable of supporting a shear horizontal wave provided on its surface with an electrode (2,3). The sensor is characterized in that the surface of the piezoelectric support (1) including the region bearing the electrode (2,3) is covered by a layer of dielectric material (9) of thickness 0.5 to 20 microns. The piezoelectric support (1) is preferably a single crystal. The dielectric layer (1) may be of, for example, silicon dioxide or a suitable polymer, and preferably has a thickness of between 0.5 and 5 .mu.m.

Abstract: A real time non-volatile residue (NVR) monitor, which utilizes surface acoustic wave (SAW) resonators to detect molecular contamination in a given environment. The SAW resonators operate at a resonant frequency of approximately 200 MHz-2,000 MHz which enables the NVR monitor to detect molecular contamination on the order of 10.sup.-11 g-cm.sup.-2 to 10.sup.-13 g-cm.sup.-2. The NVR monitor utilizes active temperature control of (SAW) resonators to achieve a stable resonant frequency. The temperature control system of the NVR monitor is able to directly heat and cool the SAW resonators utilizing a thermoelectric element to maintain the resonators at a preset temperature independent of the environmental conditions. In order to enable the direct heating and cooling of the SAW resonators, the SAW resonators are operatively mounted to a heat sink.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, a wave guide path provided on the piezoelectric substrate and an interdigital transducer for exciting a surface acoustic wave. The interdigital transducer is provided with plural portions of mutually different pitches of the electrode finger, respectively corresponding to different frequencies. The portions are parallelly arranged along a direction perpendicular to the propagation direction of the surface acoustic wave. The surface acoustic wave generated by the interdigital transducer is entered in concentrated manner into the wave guide path.

Abstract: A bandpass filter and a method for making a bandpass ladder filter having a center frequency, a first port and a second port. The method has steps of providing a first L network having a first connection, a second connection and an inductive impedance at the center frequency and providing a second L network having a first connection, a second connection and a capacitive impedance at the center frequency. The method further has steps of coupling the first connection of the first L network to the first port, coupling the first connection of the second L network to the second connection of the first L network and coupling the second connection of the second L network to the second port.

Abstract: A Passive Surface Acoustic Wave Identification Tag ("SAW-ID tag") device utilizes pulse compression techniques and a large number of coding possibilities for identifying articles at enhanced ranges. The SAW-ID tag device provides a piezoelectric substrate having bus bars, spaced electrode taps between the bus bars and a built-in antenna, with an input chirped SAW transducer having a dispersive, complementary matched filter response to an input expanded chirp signal from an expanded linear FM chirp waveform actively generated by a nearby chirp transmitter. The input expanded chirp signal is fed into the input chirped SAW transducer through the built-in antenna, to compresses the input expanded chirp signal into a narrow, compressed pulse signal propagating toward the electrodes taps. The spacing of the electrode taps establishes the desired unique time-ordered coding.

Abstract: This invention provides a surface acoustic wave device mounted module which is miniature, light, and highly reliable. The surface acoustic wave device mounted module also has excellent frequency characteristics. The surface acoustic wave device mounted module includes a multilayer substrate which has at least one layer of a shield pattern, input-output electrodes, grounding electrodes, through holes used for connecting electrodes, and a surface acoustic wave element. The surface acoustic wave element has metallic bumps, which are transfer-coated with a conductive resin, on electrode pads and an insulating resin around the surface acoustic wave element. The electrode pads are input-output terminals and grounding terminals formed on the surface acoustic wave element. Continuities between the input-output terminals and the input-output electrodes, and between the grounding terminals and the grounding electrodes are established by the through holes.

Abstract: A surface acoustic wave device includes: a holding substrate; a piezoelectric substrate; an interdigital transducer formed on the holding substrate; and supports for holding said piezoelectric substrate on the holding substrate so that the interdigital transducer is evenly in contact with the piezoelectric substrate.

Abstract: This invention relates to analyte-responsive compositions and analyte detection methods using these compositions, and, more particularly, to such compositions based on potassium titanyl phosphate (KTP) and analogs thereof and to analyte detection methods based on piezoelectric and optical properties of materials.

Abstract: In a surface acoustic wave-semiconductor composite device such as a surface acoustic wave convolver, a piezoelectric plate and a semiconductor plate are layered directly or with a gap between them. Input electrodes are provided to apply a plurality of input signals to the piezoelectric plate to excite surface acoustic waves, while an output electrode is provided to detect a convolution output signal of a change in electric potential of the semiconductor plate at an interface of the semiconductor plate with the piezoelectric plate. In the layered structure, the semiconductor plate is bonded directly to the piezoelectric plate by hydrogen bonds between hydroxyl groups or by covalent or ionic bonds of oxygen atoms with component atoms of the piezoelectric and semiconductor plates. In modified structures, an inorganic thin film is applied to one of the piezoelectric and semiconductor plates, while the inorganic thin film is bonded directly to the other of the two plates.

Abstract: A surface acoustic wave element includes a hard layer containing a composition component essentially consisting of at least one of diamond and a diamond-like carbon film, a piezoelectric layer formed on the hard layer, a silicon dioxide (SiO.sub.2) layer formed on the piezoelectric layer, and electrodes combined with the piezoelectric layer to perform electro-mechanical conversion. The surface acoustic wave element has a larger electro-mechanical coupling coefficient and a higher surface acoustic wave propagation velocity than does a conventional surface acoustic wave element having no silicon dioxide layer, thereby obtaining a surface acoustic wave element that can operate in a high-frequency range. In particular, the electro-mechanical coupling coefficient is increased. The SiO.sub.2 layer is an electric insulator and rarely reacts with moisture or acids. The SiO.sub.

Abstract: A surface acoustic wave device includes: a single crystal piezoelectric substrate; a single crystal piezoelectric thin plate formed on the single crystal piezoelectric substrate, the single crystal piezoelectric thin plate being bonded to the single crystal piezoelectric substrate by direct bonding; and interdigital transducers formed on the single crystal piezoelectric thin plate, for exciting a surface acoustic wave in at least the single crystal piezoelectric thin plate.

Abstract: Surface acoustic eave devices making use of the interaction between surface acoustic wave and carriers include at least a semiconductor part, a piezoelectric layer and an intermediate insulating film. The devices of this invention include diamond or diamond-like carbon as the insulating film in contact with the piezoelectric layer. Since diamond or diamond-like carbon has the highest sound velocity, the surface acoustic wave velocity is extremely high in the piezoelectric layer in contact with diamond or diamond-like carbon. The high surface acoustic wave velocity alleviates the need of producing fine interdigital transducers. This invention is applicable to surface acoustic wave phase-shifters, surface acoustic amplifiers and surface acoustic convolvers.

Abstract: A piezoelectric crystal element for surface acoustic wave applications with a quartz substrate with at least one substantially planar quartz surface, the planar quartz surface having an epitaxially grown layer of a quartz-isomorphous crystal with the total molecular formula ABO.sub.4, A standing for Al or Ga, and B for P or As, and the quartz surface and the epitaxial layer having approximately the same crystallographic orientation.

Abstract: A high frequency module is disclosed which comprises a high frequency device in a package, a circuit formed on a flexible substrate in the package, the circuit, the high frequency device and input/output terminals of the package being connected electrically.

Abstract: A surface acoustic wave device includes a hard layer comprising diamond or a diamond-like carbon film, and a piezoelectric layer formed on the hard layer. It further includes a paired interdigital transducer and grounding electrode, which perform an electro-mechanical conversion, with the piezoelectric layer arranged therebetween. Then, the feature of the present invention is to form the grounding electrode of a conductive oxide. It is preferred that the conductive oxide is formed by doping an impurity into a piezoelectric material of ZnO. Therefore, the adhesion between the piezoelectric layer and the hard layer, and the grounding electrodes is increased, so that the device yield is enhanced, and a high electromechanical coupling coefficient can be achieved in a high frequency range.

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 complementary acoustic charge transport circuit element comprises first and second buried channels. Each of the channels is comprised of a piezoelectric semiconductor and each channel has a source through which charge is injected and a drain through which charge is extracted. A transducer propagates an acoustic wave through each channel and the propagated waves transport the charge between the sources and the drains. A source and/or a drain of one channel is connected in parallel with the corresponding souce and/or drain of the other channel. The waves are complementary at the interconnected ones of the sources and/or the drains.

Abstract: Devices for controlling high frequency signals such as optic or electric signals are disclosed which utilize guided and/or reflected surface acoustic waves. The devices preferably use crystalline substrates modified (e.g., by ion exchange to increase mass density) to contain acoustic reflectors and/or continuous acoustic waveguiding channels (optionally, in combination with optical features such as optical waveguiding channels) and interdigital transducers deposited thereon to provide frequency generation (and reception where high frequency electrical signals are controlled). The preferred crystal substrates are of a material having a piezoelectric-elastic dielectric matrix capable of the generation of acoustic waves, such as MTiOXO.sub.4 (where M is K, Rb, Tl, and/or NH.sub.4 and X is P and/or As) having mm2 symmetry.

Abstract: A SAW oscillator circuit including a housing having disposed therein a surface wave propagation supporting substrate with a pair of transducers coupled by surface waves propagating through the substrate and electronic circuitry connected to the pair of transducers and arranged to provide, with the connected resonator, the SAW oscillator circuit. A weight is attached to the resonator. The housing is susceptible of vibratory deflections which induce vibratory deflections in the substrate and the weight suppresses the vibratory deflections induced in the substrate of the resonator. With such arrangement, while sufficiently thick externally mounted stiffeners are not used because of space limitations, the effects of vibratory deflections induced in the substrate of the insufficiently thick, or un-stiffened housing are compensated by the weight attached to the resonator.

Abstract: Surface-wave arrangement (1) having at least one surface structure (21, 22), by means of which those components of surface waves (19) which are produced in the arrangement are rendered ineffective with respect to interference which would otherwise occur, for which a sump is provided in a known manner at the end of the substrate.

Abstract: According to this invention, an SAW electric part includes an SAW filter and an SAW oscillator formed on a substrate having the same temperature characteristics as those of a substrate on which the SAW filter is formed. A frequency converter includes the SAW electric part, a second local oscillation circuit, a frequency converter, a first mixer, and a second mixer. The second local oscillation circuit oscillates a second local oscillation signal using the SAW oscillator. The frequency converter converts a frequency of the second local oscillation signal to generate a first local oscillation signal. The first mixer mixes the first local oscillation signal with an input signal to output a composite signal to the SAW filter. The second mixer mixes an output from the SAW filter with the second local oscillation signal to output a frequency conversion signal.

Abstract: A surface acoustic wave device uses a highly oriented diamond film with a planar surface, increasing the propagating velocity of a surface acoustic wave, and fabricating many devices on a large area without polishing processes. The surface acoustic wave device includes the highly oriented diamond films, a piezoelectric film and electrodes which are formed on the diamond film. In the highly oriented diamond film, 80% or more of the surface area of the diamond film is composed of the (100) faces or (111) faces of diamond; and the difference {.DELTA..alpha.,.DELTA..beta.,.DELTA..gamma.} between the Euler angles {.alpha.,.beta.,.gamma.} expressing the crystal orientations of the adjacent (100) or (111) faces of the diamond film simultaneously satisfies the relations of .vertline..DELTA..alpha..vertline..ltoreq.10.degree., .vertline..DELTA..beta..vertline..ltoreq.10.degree., and .vertline..DELTA..gamma..vertline..ltoreq.10.degree..

Abstract: A surface acoustic wave device which can operate at a higher frequency range is produced by irradiation with a focused ion beam to produce a narrower electrode width and narrower spacing width between neighboring electrodes in contact with a piezoelectric body, without degrading the reliability of the device. The surface acoustic wave device includes a piezoelectric body 3 and interdigital electrodes 2a and 2b in close contact with the piezoelectric body 3 and formed by using the focused ion beam. In order to increase the frequency of the device, the piezoelectric body 3 may be formed on a substrate 1, for example of diamond.

Abstract: A surface acoustic wave device is so manufactured that it's reliability is increased and so that it is surface-mountable with no requirement for packaging. The surface acoustic wave device (20) has a pair of opposite interdigital electrodes (2a, 2b) and a piezoelectric member (4) in close contact with the interdigital electrodes (2a, 2b). A portion located between the pair of interdigital electrodes (2a, 2b) propagates surface acoustic waves. This device (20) is characterized by an air bridge (13) covering the portion of the piezoelectric member (4) for propagating surface acoustic waves and the pair of interdigital electrodes (2a, 2b). The air bridge (13), may be provided with an insulating film (14) which is not in contact with the piezoelectric member (4).

Abstract: A method and apparatus in which signal output of an acoustic wave device is separated into desired and undesired components. An excitation signal to an input of the acoustic wave device is periodically interrupted for durations based upon the time required for acoustic waves to travel from the input to the output of the device. The duration of excitation is less than the time required for wave travel, allowing electromagnetic interference to complete its passage to the output before the arrival of acoustic wave energy. The non-simultaneous arrival of electromagnetic interference and acoustic wave-generated energy allows the electromagnetic interference to be gated from the output. Electrical switches are employed, such as double-balanced mixers or PIN diode switches. The period of pulses for providing the interruptions of excitation is at least as great as the sum of the required time for acoustic wave travel and the time during which the device is excited.

Abstract: A surface acoustic wave element is provided with a piezoelectic substrate, a first input transducer, a second input transducer and an output device such as output electrode. The piezoelectric substrate has a first and a second surfaces which are mutually faced. The first input transducer is formed on the first surface of the substrate to generate a first surface acoustic wave which propagates in a predetermined direction. The second transducer is formed on the first surface of the substrate to generate a second surface acoustic wave which propagates in a direction opposite to the predetermined direction. The output device is formed on the first surface of the substrate to extract a signal produced by an interaction of the first and second surface acoustic waves. At least part of the second surface of the substrate is caused to be inclined in a direction perpendicular to the predetermined direction with respect to the first surface.

Abstract: An acoustic or ultrasonic device includes two ultrasonic energy transmission paths having substantially identical transmission characteristics for a neutral condition of the device. One or both of the transmission paths include path altering structure(s) or coating(s) for changing the transmission characteristics of one or both of the paths in response to a physical phenomenon to be sensed or monitored. The paths have input transducers coupled thereto for transmitting ultrasonic energy into the paths. The input transducers are driven by a single oscillator such that the ultrasonic energy waves generated in the two paths are substantially identical to one another. A drive adjusting circuit compensates for any differences between the two paths and/or the ultrasonic waves in the two paths. An output transducer is coupled to the two paths for receiving ultrasonic waves from the paths and generating an output signal which is the result of combining the acoustic or ultrasonic waves from the two paths.

Abstract: A multi-bandwidth SAW filter for an input signal is provided which includes an SAW transducer having a selectable length corresponding to the desired bandwidth of the filter. The SAW filter is responsive to a control signal which corresponds to a selectable bandwidth of the filter to present the input signal to an appropriately lengthed SAW transducer.

Abstract: An opening 11 is formed in a region of a circuit board 10 opposite to a vibration region E of a piezoelectric element 5. The piezoelectric element 5 is mounted on the circuit board 10, and electrode connection portions 9 of the piezoelectric element 5 are connected with and fixed to the circuit board by a solder. In succession, soldered connection portions kept away from the vibration region E of the piezoelectric element 5 are filled with a bonding agent 8. Thereupon, an excess bonding agent 8 with which the soldered connection portions are filled is eliminated by the opening 11, and hence is prevented from invading the vibration region E of the piezoelectric element 5. Further, any stress exerted on the circuit board 10 is dispersed because of its being mostly received by the bonding agent 8, and hence any stress exerted on the piezoelectric element 5 is reduced.

Abstract: An electronic article surveillance system including a bulk acoustic wave transponder 10 coupled to an antenna 12, an interrogator 14, directional antenna 16 and an output connector 18. The transponder comprises a silicon or glass substrate 20, bus electrodes 22, 24, a launching IDT T0 and a series of "connected" and "unconnected" IDTs T1-T4. The connected/unconnected state of the respective IDTs T1-T4 may be detected and employed to generate an identification code comprising a series of binary digits. A thin copolymer piezoelectric film 26 covers the substrate 20 and electrodes T0-T4.

Abstract: A surface acoustic wave device having a diamond layer, a piezoelectric layer and a comb-like electrode, in which the piezoelectric layer and the comb-like electrode are formed on a surface of the diamond layer, which surface has been contacted to a substrate used in the formation of the diamond layer by a vapor phase growth method, which device has high stability and can be produced economically.

Abstract: A two track surface wave arrangement has improved selection property resulting from crosstalk signals of parasitic transmission paths within the arrangement being suppressed. What can be achieved with a displacement of the surface wave arrangement of one track relative to that of the other track by a dimension of nearly half a wavelength is that crosstalk signals mutually cancel on the basis of interference without affecting the useful signal.

Abstract: A low vibration sensitive SAW device includes a first quartz substrate having a pair of opposing surfaces, each surface which supports surface wave propagation. A pair of transducers are coupled to each of said surface wave propagation surfaces providing a pair of surface wave devices on opposing surfaces of the substrate. Each surface wave propagating surface is covered by a matching quartz cover and a glass-frit seal to provide a three piece all-quartz package. The pair of devices are connected together in parallel generally externally from the package, and when the dual device package undergoes vibration in a direction perpendicular to the surface wave propagation surfaces, one surface of the substrate will be subjected to a tensile strain field, whereas the opposite surface of the substrate will be subjected to identical but opposite direction strain field that is compressive.

Abstract: In a surface acoustic wave transducer having closely space-apart IDT electrode segments, a metallic oxide is selectively formed only along the marginal edge of each electrode segment so that it separates adjacent electrode segments, thereby preventing short-circuiting therebetween, permitting easy fabrication of the transducer and improving the yield rate of fabrication.

Abstract: A surface acoustic wave element has a diamond layer, a piezoelectric thin film formed on the diamond layer, and a pair of electrodes for generating a surface acoustic wave having a specific wavelength and extracting the surface acoustic wave, wherein at least one electrode is a copper electrode epitaxially grown on the surface of the diamond layer. To manufacture this surface acoustic wave element, after the diamond layer is formed on a substrate by epitaxial growth, the copper electrodes each having the predetermined shape are formed on the surface of the diamond layer by epitaxial growth. In the surface acoustic wave element having the above structure, since the copper electrodes formed on the diamond layer consist of high-quality singlecrystal copper, resistances to electromigration and stress migrations can be increased.

Abstract: A surface acoustic wave device (100) having a tunable output includes a piezoelectric substrate (120) having a surface wave propagation structure, and a mechanism (130), mechanically coupled to the substrate (120), for mechanically deforming the substrate (120) in order to modify the output (114) of the surface acoustic wave device (100).

Abstract: A piezoelectric device, such as a surface acoustic wave filter, comprises a piezoelectric film composed of a lead zirconium titanate compound applied to a substrate formed of silicon or gallium arsenide. The device includes an intermediate film between the piezoelectric film and the substrate and composed of a lead-free zirconium titanate compound to prevent interaction between lead oxide in the piezoelectric material and the material of the substrate that would otherwise cause spalling or adversely effect the electrical properties of the substrate. The piezoelectric device is made by first applying the film of the lead-free zirconium titanate compound and thereafter applying the film of the lead zirconium titanate compound. Preferably, the lead-free zirconium titanate film is applied by sputtering and annealed to densify the material and increase the dielectric constant prior to depositing the piezoelectric material.

Abstract: A pair of crystallographically matched piezoelectric substrates are sealed together to provide a package for a SAW device. A sealant material including a glass frit is deposited on a selected portion of a first one of the pair of substrates. The substrate having the sealant material is then heated to a temperature which is substantially below the glazing temperature of the sealant material to dry the sealant material. The substrate having the dried sealant material is heated a second time at a temperature just above the softening temperature of the glass frit to glaze the glass frit component with other components of the sealant material being driven from the glass frit during the heating cycles. The substrate having the glazed frit and the other remaining substrate are then mated together in a predetermined manner.

Abstract: A filter device comprises an acoustic wave propagating substrate having an effective coupling coefficient k.sup.2 and having a first filter and a second filter disposed on the acoustic wave propagating substrate. The first filter comprises a first electro-acoustic transducer and a first acousto-electric transducer, both disposed on the acoustic wave propagating substrate. The first acousto-electric transducer comprises N.sub.1 many electrode pairs, wherein N.sub.1 .gtoreq.C/k.sup.2. C is a constant having a value in the range from 1 to 2. The first acousto-electric transducer is acoustically coupled to the first electro-acoustic transducer. The second filter comprises a second electro-acoustic transducer and a second acousto-electric transducer, both disposed on the acoustic wave propagating substrate. The second electro-acoustic transducer is electrically coupled to the first acousto-electric transducer. The second electro-acoustic transducer comprises N.sub.2 many electrode pairs, wherein N.sub.2 <C/k.