Significant Transmitting Or Receiving Transducer Structure Patents (Class 333/154)
  • Patent number: 4482833
    Abstract: A transducer with thin films of gold having a high degree of orientation on surfaces previously yielding only unoriented gold has a layer of glass over the surface of the substrate material followed by a layer of oriented gold over the layer of glass. The added layer of piezoelectric material over the layer of oriented gold provides piezoelectric material having good orientation due to the oriented gold. Addition of a top conductive electrode forms a transducer wherein the piezoelectric material has a high degree of orientation.
    Type: Grant
    Filed: January 4, 1984
    Date of Patent: November 13, 1984
    Assignee: Westinghouse Electric Corp.
    Inventors: Robert W. Weinert, Donald H. Watt
  • Patent number: 4480209
    Abstract: A surface acoustic wave device includes a silicon substrate having a main surface with a given crystalline orientation, a zinc oxide layer deposited on the main surface of the silicon substrate and a dielectric layer as well as electrodes both formed in contact with said zinc oxide layer, so that a surface acoustic wave will be propagated along a given crystalline axis direction of the silicon substrate.
    Type: Grant
    Filed: October 8, 1982
    Date of Patent: October 30, 1984
    Assignee: Clarion Co., Ltd.
    Inventors: Takeshi Okamoto, Ryuichi Asai, Shoichi Minagawa
  • Patent number: 4477784
    Abstract: A dispersive acoustic delay line using reflection on slanted gratings is provided. This device comprises slanting input and output transducers each formed of pair electrode fingers. The interval of the electrodes of different polarity varying from nv/2f.sub.min to nv/2f.sub.max, where v is the speed of the waves, f.sub.min and f.sub.max the endmost frequencies of the frequency band and n the number of the harmonic on which the transducers operate. The interval of the gratings varies from kv/f.sub.min to kv/f.sub.max, where k is the number of the operating harmonic of the network, with n.noteq.k.
    Type: Grant
    Filed: September 27, 1982
    Date of Patent: October 16, 1984
    Assignee: Thomson-CSF
    Inventors: Charles Maerfeld, Claude Lardat
  • Patent number: 4473767
    Abstract: A surface acoustic wave convolver comprises a piezoelectric substrate on which a plurality of conductive strip electrodes, an input signal transducer and a reference signal transducer are formed, and a semiconductive substrate on which depletion layer control electrodes and capacitance read-out electrodes are formed. The conductive strip electrodes are connected to the depletion layer control electrodes so that an output signal is taken up from the capacitance read-out electrodes.
    Type: Grant
    Filed: November 2, 1982
    Date of Patent: September 25, 1984
    Assignee: Clarion Co., Ltd.
    Inventors: Shoichi Minagawa, Takamasa Sakai, Takeshi Okamoto
  • Patent number: 4464639
    Abstract: Disclosed is a surface acoustic wave filter based on a ferroelectric crystal having a plurality of ordered domains of alternating polarity. An output interdigital transducer, with at least one pair of electrodes, is deposited on a surface of the crystal so that each of the electrode pairs corresponds to one of the ordered domains, and an input interdigital transducer is oriented on the surface to direct a surface acoustic wave toward the output transducer. In addition, sources of both positive and negative electrical potential may be provided, with a switch for each output electrode pair to selectably apply either the positive or the negative potential to that pair.
    Type: Grant
    Filed: September 17, 1982
    Date of Patent: August 7, 1984
    Assignee: Rockwell International Corporation
    Inventor: Edward J. Staples
  • Patent number: 4464597
    Abstract: A withdrawal transducer structure is employed in a narrow-band surface acoustic wave device requiring many pairs of interdigital transducer fingers or in a high-frequency surface acoustic wave device in which the thickness of interdigital transducer fingers is large relative to the wavelength of the surface acoustic wave, so that the interdigital transducer fingers may not severely adversely affect the characteristics of the device. The interdigital transducer fingers in the input and output piezoelectric transducers are suitably partly omitted leaving some of them or dummy fingers are additionally provided to eliminate the adverse effect of the interdigital transducer fingers on the characteristics of the device, so that the narrow-band or high-frequency surface acoustic wave device can operate with improved performance without having any unnecessary frequency response.
    Type: Grant
    Filed: January 27, 1982
    Date of Patent: August 7, 1984
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Kentaro Setsune
  • Patent number: 4462011
    Abstract: Pairs of input transducers are formed on the surface of a piezoelectric crystalline body. The input transducers in each pair produce adjacent parallel surface acoustic waves of opposite polarity and specific phase difference which are sensed by a corresponding output transducer. The input transducers of each pair are offset from one another by amounts related to the wavelength of the surface acoustic wave so that a maximum cancellation of the voltages induced in the output transducers by the acoustic waves can be used to indicate the relative delay or phase difference of signals applied to the input terminals and to do so in a manner which is insensitive to temperature variation from one point to another in the piezoelectric crystal.
    Type: Grant
    Filed: December 27, 1982
    Date of Patent: July 24, 1984
    Assignee: Lockheed Missiles & Space Company, Inc.
    Inventor: Robert B. Ward
  • Patent number: 4450374
    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.
    Type: Grant
    Filed: May 27, 1982
    Date of Patent: May 22, 1984
    Assignee: Motorola Inc.
    Inventors: Frederick Y. Cho, Fred S. Hickernell
  • Patent number: 4449107
    Abstract: A surface elastic wave element comprising a (110)-oriented silicon substrate, a zinc oxide layer formed on the silicon substrate and electrodes formed on the zinc oxide layer so as to propagate surface elastic wave to the [001]-axis direction of the zinc oxide layer.
    Type: Grant
    Filed: March 3, 1982
    Date of Patent: May 15, 1984
    Assignee: Clarion Co., Ltd.
    Inventors: Ryuichi Asai, Takeshi Okamoto, Shoichi Minagawa
  • Patent number: 4437031
    Abstract: A separate comb transducer is disclosed in a ZnO/Si SAW device to enable doubling of the possible operating frequency for a given photolithographic capability of the device. Frequency doubling is made possible by a single-phase structure having conductive and non-conductive surfaces equal to one-half of the SAW wavelength. By connection of two such structures in parallel, a balanced separate comb transducer is achieved for reducing signal levels due to direct coupling that otherwise occurs in the single-phase structure. Separate comb grating transducers are also disclosed to enable fabrication of higher frequency MZOS convolvers, with both the separate comb transducer and separate comb grating transducer being shown utilized in both the Rayleigh and Sezawa modes.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: March 13, 1984
    Assignee: Purdue Research Foundation
    Inventors: Robert L. Gunshor, Robert F. Pierret, Michael R. Melloch
  • Patent number: 4427954
    Abstract: A pulse compression filter designed as a dispersive delay line functions with acoustic waves having a mean wavelength .lambda..sub.o in the filter. At least one input/output transducer or at least one reflector arrangement is provided with a plurality of electrode respectively reflector fingers distributed on a substrate in accordance with a prescribed transfer function which has a given bandwidth and whose Fourier transform has a given time duration T. Said fingers are divided into a plurality of N finger groups designed identical to one another with respect to the number fingers n and corresponding finger spacings of corresponding fingers. Each finger group has a length in a propagation direction of the acoustic wave in the filter which is at least equal to the mean wavelength .lambda..sub.o. Center spacings of adjacent finger groups from one another are non-equidistant in accordance with the prescribed transfer function.
    Type: Grant
    Filed: May 12, 1982
    Date of Patent: January 24, 1984
    Assignee: Siemens Aktiengesellschaft
    Inventors: Richard Veith, Helmut Stocker
  • Patent number: 4422000
    Abstract: A surface acoustic wave device on a piezoelectric substrate comprises an interdigital transducer having an interdigital sending part in the forward direction and an interdigital reflecting part in the reverse direction. An electrical phase difference of .phi. (radian) is applied between the sending and reflecting parts, while the distance between the sending and reflecting parts providing a geometrical phase difference therebetween is established to be ##EQU1## where n is a positive integer and .lambda..sub.o is the wavelength of surface acoustic wave. A third, common electrode meanders between the sending and reflecting electrodes.
    Type: Grant
    Filed: May 4, 1982
    Date of Patent: December 20, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Jun Yamada, Katashi Hazama
  • Patent number: 4420728
    Abstract: A surface acoustic wave filter includes a length-weighted interdigital transducer (T1) on one side of which are bus bar parts (BP1, BP2) which are within the transducer acoustic aperture (A), are inclined at an acute angle to the propagation path (P) and which closely follow the major lobe (L1). These bus bar parts each have a width (W) along the propagation path (P) defined by 2W=n.lambda./2 where n is an odd integer and .lambda. is the wavelength of surface acoustic waves at substantially the maximum amplitude response frequency of the transducer (T1).
    Type: Grant
    Filed: December 3, 1981
    Date of Patent: December 13, 1983
    Assignee: U.S. Philips Corporation
    Inventor: David E. Bower
  • Patent number: 4409567
    Abstract: A surface acoustic wave (SAW) device includes a SAW element disposed on a printed circuit. The printed circuit has an insulation substrate having input and output wiring conductors and input side and output side grounding conductors formed thereon. Interdigital transducers of the SAW element are connected to the input and output wiring conductors. The input side grounding conductors and the output side grounding conductors are disposed apart from each other with an isolation gap inbetween, thereby obtaining desirable filtering characteristics by suppressing undesirable coupling between input side and output side caused by a feed through electromagnetic wave.
    Type: Grant
    Filed: December 24, 1980
    Date of Patent: October 11, 1983
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kentaro Setsune, Toshihide Tanaka
  • Patent number: 4409570
    Abstract: A separated substrate acoustic wave device having an active piezoelectric substrate and a separate base substrate. Input and output transducers are mounted upon the base substrate. The active substrate, which includes grooved-array reflectors in the case of resonators, is mounted opposite the base substrate so that it does not contact the transducer electrodes and further so that electric fringing fields generated in the transducers will induce an acoustic wave due to the piezoelectric effect in the active substrate. Similarly, acoustic waves propagating in the active piezoelectric substrate will have an associated electric field which induces an electrical signal in the transducer permitting detection of the acoustic waves propagating in the active substrate.
    Type: Grant
    Filed: November 16, 1981
    Date of Patent: October 11, 1983
    Assignee: Sperry Corporation
    Inventor: William J. Tanski
  • Patent number: 4405874
    Abstract: To enable increased power coupling into a SAW device for which voltage breakdown is a limiting factor in determining the maximum power which can be coupled, each transducer of the SAW device is replaced by a plurality of series-connected inter-digital transducers (IDTs). For operation in an Nth harmonic mode, there may be N series-connected IDTs which are offset from one another by 1/N wavelengths of the fundamental frequency for which the individual IDTs are designed; for high frequency SAW devices, this further increases the power which can be coupled into the device. The SAW device is particularly useful in a delay-line oscillator to constitute a microwave source for a local oscillator in a radio repeater.
    Type: Grant
    Filed: March 1, 1982
    Date of Patent: September 20, 1983
    Assignee: Northern Telecom Limited
    Inventor: Mark S. Suthers
  • Patent number: 4403202
    Abstract: A surface acoustic wave device wherein a laminated structure comprised of a piezoelectric member and a metal electrode or electrodes is provided on a surface acoustic wave surface of an elastic body and an acoustic impedance discontinuous face is formed on the elastic body, so that a longitudinal wave generated by the laminated structure is reflected by the acoustic impedance discontinuous face to provide a transverse wave.
    Type: Grant
    Filed: March 27, 1981
    Date of Patent: September 6, 1983
    Assignee: Clarion Co., Ltd.
    Inventor: Shoichi Minagawa
  • Patent number: 4393358
    Abstract: In a surface acoustic wave filter which employs a multi-strip coupler to offset the acoustic wave path, diffraction effects lead to spurious responses at a filter trap frequency. The diffracted wavefronts are curved, instead of being straight and parallel to the transducer fingers as are the wavefronts of the strip-coupled acoustic signal. Thus an additional transducer is employed which has fingers slanted at the same angle as the local wavefronts of the diffracted acoustic energy. The resulting parallel relationship permits the additional transducer to be designed so that it compensates for the undesired trap frequency response by producing an equal magnitude, oppositely phased trap frequency output. In order to conserve substrate area, a technique is disclosed for locating the compensating transducer within a dummy area of an apodized main receiving transducer.
    Type: Grant
    Filed: November 18, 1981
    Date of Patent: July 12, 1983
    Assignee: Zenith Radio Corporation
    Inventor: Adrian J. De Vries
  • Patent number: 4390807
    Abstract: In a preferred embodiment, a surface acoustic wave device comprises a piezoelectric substrate, a first electrode formed on the substrate and acting to convert an electrical signal into a surface acoustic wave, and second and third electrodes formed on the substrate and acting to convert the surface acoustic wave into an electrical signal. The second and third electrodes are disposed at different distances from the first electrode and connected electrically with each other. Electrode fingers of the second electrode are arranged in a relationship of the opposite polarity with respect to those of the third electrode so as to cause peaks in the constant frequency interval multi-peak frequency characteristics of the device acting as a filter to take place at frequencies which are (integer+1/2) times the constant frequency interval .DELTA.f. In another preferred embodiment, a plurality of surface acoustic wave device units are formed on a common piezoelectric substrate.
    Type: Grant
    Filed: January 7, 1982
    Date of Patent: June 28, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Kiyoharu Kishimoto, Katashi Hazama, Akitsuna Yuhara
  • Patent number: 4389590
    Abstract: A waveform recorder wherein surface acoustic waves excited in a piezoelecc-insulator-semiconductor layered structure produce a traveling electric field in the semiconductor substrate. Charges stored in the traveling potential wells and representing the instantaneous amplitude of a waveform to be recorded are transferred at high speed and density to different respective spatial locations. Because each successive well represents a different time instant of the waveform, the different spatial locations correspond to different times. The output signal from each of the locations can be selectively delayed before application to a display oscilloscope to enable display of the waveform at a rate many times slower than the actual frequency of the signal waveform.
    Type: Grant
    Filed: August 26, 1981
    Date of Patent: June 21, 1983
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Robert R. Whitlock
  • Patent number: 4384264
    Abstract: A surface acoustic wave device comprises a substrate and a set of interdigital electrodes disposed thereon and spaced apart. One interdigital electrode is divided along the propagating direction of the surface acoustic wave into a plurality of portion interdigital electrodes which are electrically connected in series. The electrode pattern of the one interdigital electrode is formed asymmetrically such that the static capacitances of at least two adjacent portion electrodes thereof are different from each other, preferably in such a manner that when the device is installed, the total effective static capacitances of the two adjacent portion electrodes will be substantially equal. The static capacitance of the portion electrode having a comb shaped electrode thereof which is to be grounded is selected to be smaller than that of the other portion electrode.
    Type: Grant
    Filed: April 18, 1980
    Date of Patent: May 17, 1983
    Assignee: Murata Manufacturing Company Ltd.
    Inventor: Michio Kadota
  • Patent number: 4365219
    Abstract: A SAW filter assembly module comprising a plurality of series in-line SAW filter devices and effective to provide substantial isolation of output from input of the module. Separate isolated conductive ground areas are applied to the surface of an insulative substrate upon which the SAW filter devices are placed with a portion of certain areas extending to a terminal side of the substrate and each SAW device is electrically connected to a respective conductive ground area. A separate inter-SAW ground area is provided between each set of device ground areas. A conductive input area of a first SAW filter is located most distant from the conductive output area of a subsequent SAW filter with the plurality of conductive ground areas located therebetween to increase selectivity. A conductive shield is secured to and electrically connected to a ground area between the SAW filter devices and is positioned to block radiative signals between the devices.
    Type: Grant
    Filed: February 27, 1981
    Date of Patent: December 21, 1982
    Assignee: General Electric Company
    Inventor: Bernard D. Nathan
  • Patent number: 4365220
    Abstract: Stripes of a transducer or a reflector in a surface acoustic wave device are arranged such that the distribution of effective lengths of interdigital electrodes follows a function of impulse response in the direction of propagation of an acoustic wave and a total number of stripes in the direction of propagation is equal for each section in the direction normal to the direction of propagation, in order to attain a desired frequency response without sacrificing a transfer efficiency.
    Type: Grant
    Filed: March 20, 1981
    Date of Patent: December 21, 1982
    Assignee: Hitachi, Ltd.
    Inventor: Mitsutaka Hikita
  • Patent number: 4363990
    Abstract: A surface acoustic wave transducer having a piezoelectric thin film, interdigital electrodes disposed on one side surface of said piezoelectric thin film and an apodized counter electrode disposed on the opposite-side surface of said piezoelectric thin film. The outline of the apodized counter electrode is composed of parallel edges parallel to fingers of the interdigital electrode and perpendicular edges perpendicular to the fingers. The parallel edges are positioned in gaps between the fingers, so as not to lie over the fingers. Such structure remarkably reduces the deviation of characteristics of the transducer due to the incomplete alignment of the counter electrode with the interdigital electrode.
    Type: Grant
    Filed: December 3, 1980
    Date of Patent: December 14, 1982
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Osamu Yamazaki, Junichi Inohara, Kazuo Tazuke, Kiyotaka Wasa
  • Patent number: 4364016
    Abstract: A method for trimming the resonant frequency of fabricated SAW devices. The resonant frequency of SAW devices of the type having a substrate with structures made of a second material, other than the substrate material, upon its surface, is decreased by removing quantities of the substrate material until the desired change in frequency is obtained. In one embodiment, the substrate material of the SAW device is removed by etching the substrate in a fluorocarbon plasma, which leaves the structure made of the second material substantially unchanged. In a second embodiment, the resonant frequency of SAW resonators is increased by heating the SAW device at a temperature in excess of 250.degree. C. until the desired change in resonant frequency is obtained.
    Type: Grant
    Filed: November 3, 1980
    Date of Patent: December 14, 1982
    Assignee: Sperry Corporation
    Inventor: William J. Tanski
  • Patent number: 4354130
    Abstract: This invention provides a surface acoustic wave device which comprises a multi-layered substrate. The multi-layered substrate comprises at least a piezoelectric zinc oxide layer, an intermediate silicon oxide layer and an .alpha.-Al.sub.2 O.sub.3 base made of a single crystal havine an (0112) crystallographic plane or an equivalent crystallographic plane. This surface acoustic wave device is operable at ultra-high frequency.
    Type: Grant
    Filed: December 5, 1980
    Date of Patent: October 12, 1982
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shusuke Ono, Tsuneo Mitsuyu, Osamu Yamazaki, Kiyotaka Wasa
  • Patent number: 4350916
    Abstract: An acoustic wave device wherein each electrode element of an interdigital transducer is buried or embedded between a pair of layers of piezoelectric material. The use of a multi-layer stack of layers of piezoelectric material enables each electrode element of the transducer to be sandwiched between a distinct pair of layers and thus to be insulated from the other electrode element or elements. Because of the insulation thus provided, the spacing between the fingers of each electrode element may be selected without fear of causing short circuits between electrode elements.
    Type: Grant
    Filed: June 27, 1980
    Date of Patent: September 21, 1982
    Assignee: Rockwell International Corporation
    Inventors: Rudolf R. August, Dean B. Anderson, Shi-Kay Yao
  • Patent number: 4344049
    Abstract: A surface wave component has a pair of interdigital transducer comb structures carried spaced apart on a surface of a substrate which is carried on a base plate. In one embodiment, signal leads extend beneath the substrate to areas adjacent the rear portions of the comb structures and are capacitively coupled thereto via the substrate which is a dielectric. In another embodiment, inductive coupling loops interconnect the rear portions of the comb structures of a respective transducer and another inductive loop is carried on the opposite side of the substrate for signal coupling. In both embodiments both symmetrical and asymmetrical signal coupling is provided by utilizing a grounding plate or layer as a signal lead.
    Type: Grant
    Filed: August 27, 1980
    Date of Patent: August 10, 1982
    Assignee: Siemens Aktiengesellschaft
    Inventor: Friedrich Grobe
  • Patent number: 4344051
    Abstract: In order to bring about a reduction in the reflection coefficient due to reflections on the successive fingers of a transducer in the form of interdigitated transducer elements with split fingers of unequal length when a load impedance is applied at the terminals thereof, the invention provides for the displacement of at least the smallest minor lobe of the pulse response envelope, whose design is reproduced by the fingers, in order to position it in front of one of the maxima of the major lobe.
    Type: Grant
    Filed: January 24, 1980
    Date of Patent: August 10, 1982
    Assignee: Thomson-CSF
    Inventor: Gerard Coussot
  • Patent number: 4333065
    Abstract: In order to reduce the reflectivity of an apodized surface acoustic wave transducer, one portion of the dummy area thereof is bare and another portion is 100% metallized, and the boundary between these two regions is shaped to equalize total acoustic transit times across the transducer aperture. This avoids any net refraction, and thus permits any acoustic wavefronts which traverse the two regions to remain flat.
    Type: Grant
    Filed: October 9, 1980
    Date of Patent: June 1, 1982
    Assignee: Zenith Radio Corporation
    Inventor: Adrian J. DeVries
  • Patent number: 4330767
    Abstract: A surface acoustic wave device is provided which includes a phase-modulated interdigital electrode and a uniform interdigital electrode having an equal electrode finger width and spacing, and the device is arranged to avoid occurrence of deviation of the actual performance thereof from the designed one. To this end, the electrode finger width and spacing of the uniform interdigital electrode are determined such that the ratio of metal surface to unmetallized substrate area in the phase-modulated interdigital electrode becomes equal to the ratio of metal surface to unmetallized substrate area in the uniform inter-digital electrode.
    Type: Grant
    Filed: September 25, 1980
    Date of Patent: May 18, 1982
    Assignee: Toko, Inc.
    Inventors: Hajime Miyajima, Akio Nakakura
  • Patent number: 4328473
    Abstract: A SAW signal processor (20) includes a plurality of FET taps (30-32) having individually programmable source-drain bias (42-44) which controls both the amplitude and phase of the mixing efficiency of internal product mixing of the waves passing beneath the tap, in dependence upon the amplitude and polarity of the bias, the sources (34) of the taps may be interconnected so as to provide a summation of correlation at the output (40). The gates (35) of each of the taps are ohmically isolated, thereby to mitigate intertap interaction. The invention is a direct improvement over U.S. Pat. No. 4,207,546.
    Type: Grant
    Filed: November 3, 1980
    Date of Patent: May 4, 1982
    Assignee: United Technologies Corporation
    Inventors: Gary K. Montress, Thomas W. Grudkowski
  • Patent number: 4321565
    Abstract: A sensor formed on the surface of a body of piezoelectric material. Two input transducers disposed on the surface in parallel spaced apart relation produce surface acoustic waves in the body in response to the application of signals to the input transducers. A row of output transducers is disposed on the surface between the input transducers. Individual output transducers are offset from one another by amounts related to the wavelength of the surface acoustic wave so that at or near only one of the output transducers will the two surface acoustic waves from the input transducers cancel each other. An analog circuit and a digital circuit for ascertaining which output transducer experiences maximum cancellation to afford a determination of the delay difference between the two signals applied to the input transducers.
    Type: Grant
    Filed: July 18, 1980
    Date of Patent: March 23, 1982
    Assignee: Lockheed Missiles & Space Co., Inc.
    Inventor: Robert B. Ward
  • Patent number: 4315228
    Abstract: Apparatus for providing a plurality of filtered outputs is described incorporating a substrate suitable for propagating surface acoustic waves having an input transducer, a first plurality of spaced-apart taps coupled together, a second plurality of spaced-apart taps coupled together where at least two of the second plurality of taps are positioned in spaces between the first plurality of taps.The invention overcomes the problem of providing separate substrate surface area for each plurality of taps coupled together.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: February 9, 1982
    Assignee: Westinghouse Electric Corp.
    Inventor: Robert A. Moore
  • Patent number: 4315275
    Abstract: That face of the non-epitaxied substrate of high resistivity which supports the junction 3 formed by the planar method is treated by a mesa attack in such a way that it is smaller than the opposite face 7. An insulating ring 4 covers the periphery of the junction and projects beyond the substrate. This ring has external dimensions smaller than those of the face 7 beyond which it projects. A metallic layer 6 ensuring an ohmic contact covers in particular the lateral walls of the diode created by the mesa attack except for those zones of these walls beyond which the insulating ring 4 projects. This metallization of the lateral walls acts as an electrode and connects the diodes generally formed on one and the same substrate to one another.
    Type: Grant
    Filed: June 25, 1979
    Date of Patent: February 9, 1982
    Assignee: Thomson-CSF
    Inventors: Alain Bert, Bernard Leclerc, Yves Archambault
  • Patent number: 4314214
    Abstract: The invention relates to a magnetostatic-wave device whose ferrimagnetic layer supports an exchange structure formed by an array of conducting strips having their ends connected by conducting bridges. The invention applies particularly to the construction of magnetostatic-wave devices using couplers, hybrid junctions, reflecting mirrors, extraction structures and resonators.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: February 2, 1982
    Assignee: Thomson-CSF
    Inventors: Jean P. Castera, Pierre Hartemann, Jean M. Dupont
  • Patent number: 4307356
    Abstract: A surface acoustic wave device includes a piezoelectric substrate and a transmitting, a receiving and a reflecting transducer disposed thereon in a row along a predetermined path. The transmitting transducer is responsive to an input signal having a predetermined center frequency for propagating a first surface acoustic wave along the predetermined path. The receiving transducer is located at a location spaced a predetermined distance from the transmitting transducer and is adapted to convert the first acoustic wave to an electrical output signal, but also generates an undesired reflected wave. The reflecting transducer is provided close to one of the other two above-described transducers and is responsive to the first surface acoustic wave to generate a cancellation reflected wave which cancels the undesired reflected wave.
    Type: Grant
    Filed: July 3, 1980
    Date of Patent: December 22, 1981
    Assignee: Murata Manufacturing Co., Inc.
    Inventor: Seiichi Arai
  • Patent number: 4267533
    Abstract: An acoustic surface wave device including a three-phase unidirectional transducer. The transducer has three sets of interdigitated electrodes. The first and second sets of electrodes are each connected to bus bars, one on each side of the central axis of the transducer. The electrodes of the third set are connected to two bus bars one on each side of the central axis. The structure of the third set of electrodes and the bus bars connected thereto is symmetrical with respect to the central axis. The balanced structure of the transducer permits simplified impedance-matching and phase-shifting networks for enabling three-phase unidirectional operation of the transducer from a single phase electrical source.
    Type: Grant
    Filed: February 1, 1980
    Date of Patent: May 12, 1981
    Assignee: GTE Laboratories Incorporated
    Inventors: Martin E. Dempsey, Ching W. Lee
  • Patent number: 4263571
    Abstract: A broad-band surface acoustic wave filter of turn reflector type in which the number N of thin film finger or stripe electrode pairs in at least one transducer is selected to satisfy N=F/k.sup.2 to obtain a flat selected band in the frequency response, where F is the constant determined by the material of the used piezo-electric substrate and "k.sup.2 " is the electro-mechanical coupling coefficient.
    Type: Grant
    Filed: November 15, 1979
    Date of Patent: April 21, 1981
    Assignee: Hitachi, Ltd.
    Inventors: Yasuaki Kinoshita, Mitsutaka Hikita
  • Patent number: 4263569
    Abstract: A surface acoustic wave filter is disclosed having an interdigitated structure of transducer fingers on a piezo substrate. Spurious signals are suppressed by employment of a slanted placement of transducer fingers at an output region of a weighted input transducer or at an input region of a weighted output transducer.
    Type: Grant
    Filed: August 15, 1979
    Date of Patent: April 21, 1981
    Assignee: Siemens Aktiengesellschaft
    Inventor: Frank Moellmer
  • Patent number: 4259726
    Abstract: A diode array convolver using narrow rails on a transparent piezoelectric substrate to support a MESA diode array.
    Type: Grant
    Filed: November 3, 1978
    Date of Patent: March 31, 1981
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Robert Joly
  • Patent number: 4258342
    Abstract: An elastic surface wave device including interdigital finger electrodes comprising interdigital fingers each of which consists of a pair of divided finger elements having an equal width. The spacing between adjacent ones of the interdigital fingers is equal to the spacing between the pair of divided finger elements thereof. Importantly, at least one of the interdigital fingers is differentiated from the remainder of the interdigital fingers in respect of the distance from the center of the spacing between one of the interdigital fingers and that one of the interdigital fingers which is adjacent thereto on one side to the center of the spacing between the aforementioned one interdigital finger and that one of the interdigital fingers which is adjacent thereto on the other side. Furthermore, the interdigital finger electrode is designed such that the width of the respective finger elements is equal to the spacing therebetween.
    Type: Grant
    Filed: August 24, 1979
    Date of Patent: March 24, 1981
    Assignee: Toko, Inc.
    Inventors: Hajime Miyajima, Akio Nakakura
  • Patent number: 4257021
    Abstract: An elastic surface wave filter including on the surface of a plate, an emitting transducer, a surface wave coupler, and means for receiving the waves radiated by the coupler. The means for receiving includes two transducers each having two terminals with one terminal of each being in common with one terminal of the other. The common terminal serves as a phase reference and the voltages induced at the remaining terminals are in phase opposition to one another in the transmission band of the filter.
    Type: Grant
    Filed: June 6, 1979
    Date of Patent: March 17, 1981
    Assignee: Thomson-CSF
    Inventors: Gerard Coussot, Olivier Menager, Michel Van Den Driessche
  • Patent number: 4243960
    Abstract: A method and device for adjusting the center frequency after fabrication of surface acoustic wave (SAW) devices by the deposition of a nonconducting coating which alters the SAW propagation velocity of the device.
    Type: Grant
    Filed: August 14, 1978
    Date of Patent: January 6, 1981
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: David J. White, Carl N. Helmick, Jr., Robert E. Hunt
  • Patent number: 4224683
    Abstract: An acousto-electric convolver having a relatively long effective interaction region for counter-propagating surface acoustic waves and, therefore, a relatively large time-bandwith product implemented by distributing a coupler, such as a multistrip coupler or an array of interdigital transducer taps, over a plurality of parallel-connected single-channel acousto-electric convolvers.
    Type: Grant
    Filed: August 25, 1978
    Date of Patent: September 23, 1980
    Assignee: Rockwell International Corporation
    Inventor: Larry R. Adkins
  • Patent number: 4223284
    Abstract: An acoustic surface wave device comprises a transducer including an interdigital electrode formed on the surface of a piezoelectric material substrate and cooperative with the same for converting an electrical signal into an acoustic surface wave and vice versa. The interdigital electrode comprises at least two divided comb shaped electrodes divided in the propagating direction of the acoustic surface wave and a common comb shaped electrode commonly coupled in an interdigital manner to the two divided comb shaped electrodes. Thus, the above described two comb shaped electrodes are disposed such that both divided electrodes arranged in succession in the propagating direction of the acoustic surface wave while the fingers of both divided electrodes extend in the same direction and the common comb shaped electrode is disposed such that the fingers of the common comb shaped electrode are interdigitated with the fingers of both divided comb shaped electrodes.
    Type: Grant
    Filed: October 30, 1978
    Date of Patent: September 16, 1980
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Atsushi Inoue, Hiromichi Yamada, Kenji Suzuki
  • Patent number: 4209759
    Abstract: The invention relates to an interaction device comprising a non-magnetic substrate, a thin easy-plane magnetic layer, two piezoelectric transducers arranged at the ends of the magnetic layer and respectively receiving the two electrical signals to be treated. The signals applied are converted into elastic surface waves which are transmitted to the magnetic layer in the form of magnetoelastic waves propagated in opposite directions. The device is subjected to an external magnetic field. The variations in magnetization in the interaction zone are collected by a detection plate and characterize the interaction between the two signals.
    Type: Grant
    Filed: October 20, 1978
    Date of Patent: June 24, 1980
    Assignee: Thomson-CSF
    Inventor: Gerard Volluet
  • Patent number: 4201964
    Abstract: To eliminate disturbance signals caused by the reflection from the unitary stem areas of comb-like electrodes of an interdigital transducer in an elastic surface wave device, the edges of the unitary stem areas perpendicular to the surface wave propagating direction includes at least one pair of partial edges, the positions of the partial edges in each of the at least one pair of partial edges differ by (2n+1).multidot..lambda./4 from each other in the surface wave propagating direction, and the lengths of the partial edges in the each pair are equal to each other, where n represents zero or a positive integer and .lambda. represents the wavelength of the elastic surface.
    Type: Grant
    Filed: June 20, 1978
    Date of Patent: May 6, 1980
    Assignee: Hitachi, Ltd.
    Inventors: Yoshihiko Noro, Katashi Hazama, Jun Yamada, Hitoshi Yanagihara, Michiyori Miura
  • Patent number: 4199737
    Abstract: A magnetostatic wave device for microwave signal processing which includes an input or output transducer finger arrangement which allows shaping of the device response. Two sets of interdigitated fingers are connected to receive the same microwave input signal which is power divided between the two sets. The fingers of one set are substantially parallel to, and in side-by-side relationship with, the fingers of the other set. The device may be used for delay lines, filters, signal correlation, oscillators and numerous other microwave signal processing arrangements.
    Type: Grant
    Filed: October 18, 1978
    Date of Patent: April 22, 1980
    Assignee: Westinghouse Electric Corp.
    Inventors: Ralph W. Patterson, Terence W. O'Keeffe, John D. Adam
  • Patent number: 4194171
    Abstract: A material suitable for the propagation of acoustic waves on its surface prises a substrate of semiconductor material, of which there exists an oxide, excluding the class of piezoelectric materials, the substrate having at least one flat surface. A layer of thermally grown oxide of the semiconductor material, is disposed on the flat surface. A film of titanium, approximately 300 angstroms thick, is disposed on at least a part of the layer of oxide. A layer of vacuum-deposited metal is disposed on the film of titanium. A layer of a piezoelectrid vacuum-sputtered material is on the layer of vacuum-deposited metal and on the oxide. The semiconductor material may be silicon, the oxide may be silicon dioxide, the piezoelectric material may be zinc oxide, and the metal may be gold.
    Type: Grant
    Filed: July 7, 1978
    Date of Patent: March 18, 1980
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventor: Edward C. Jelks