Surface Acoustic Wave Devices Patents (Class 310/313R)
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Patent number: 5929723Abstract: In the electrode of a surface acoustic wave apparatus, the element concentration of copper in the aluminum alloy film is higher in the neighbors of grain boundary than the concentration within the crystal grain, and segregates to the neighbors of crystal grain boundary. In the electrode of this surface acoustic wave apparatus, the concentration of copper existing in the form of copper element, rather than in the form of intermetallic compound of copper and aluminum precipitated to the crystal grain boundary, is higher in the crystal grain boundary than the concentration within the crystal grain, and is in the segregation state. A ratio of a copper concentration in the neighbors of grain boundary to a copper concentration within the crystal grain in an aluminum alloy film forming an electrode of a surface acoustic wave apparatus is greater than 1.6. It is preferable that an electrode formed on a surface of the piezoelectric substrate is made of an aluminum alloy film doped with a copper in a range from 0.Type: GrantFiled: May 7, 1997Date of Patent: July 27, 1999Assignee: TDK CorporationInventors: Noritoshi Kimura, Masahiro Nakano, Michiyuki Nakazawa, Katsuo Sato
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Patent number: 5920142Abstract: The present invention relates to an electronic part used for mobile communications apparatuses and the like, and more particularly to an electronic part, such as an acoustic surface-wave device, a piezoelectric ceramic device or the like, which requires an oscillation space near the surface of the functional device chip thereof, and a method of production thereof. With this method, a space retainer for forming a sealed space at the functional portion of the chip can be hermetically sealed and have high moisture resistance, and the process of forming the space retainer can be carried out easily.Type: GrantFiled: March 10, 1997Date of Patent: July 6, 1999Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Keiji Onishi, Hideki Iwaki, Shun-ichi Seki, Yutaka Taguchi, Tsukasa Shiraishi, Yoshihiro Bessho, Osamu Kawasaki, Kazuo Eda
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Patent number: 5918258Abstract: A real time nonvolatile residue (NVR) monitor operates to efficiently detect molecular contamination in a given environment. The present NVR monitor utilizes surface acoustic wave (SAW) resonators in a controlled environment which efficiently promotes deposition of NVR on the sensor surface. The SAW resonators preferably 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 and to thermally separate NVR from a sample fluid contacting the SAW. 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 in accordance with optimal environmental conditions for separating NVR from the sample fluid.Type: GrantFiled: July 11, 1996Date of Patent: June 29, 1999Inventor: William D. Bowers
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Patent number: 5909156Abstract: A surface acoustic wave device includes an electrode formed by a first film and a second film on a substrate, the first film including an Al film or a film formed by adding at least one other element to Al, and the second film including a metal whose coefficient of diffusion into Al is greater than a self diffusion coefficient of Al. The present invention contributes to improvement of the high-power durability of the electrodes.Type: GrantFiled: December 11, 1996Date of Patent: June 1, 1999Assignee: Fujitsu LimitedInventors: Tokihiro Nishihara, Hidema Uchishiba, Osamu Ikata, Yoshio Satoh
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Patent number: 5909157Abstract: A surface acoustic wave filter device suitable for CDMA communication system, includes a piezoelectric substrate, and a unidirectional input side transducer and a bidirectional output side transducer are formed on the substrate. The filter device has satisfactory filtering characteristics in terms of insertion loss, frequency characteristic, T.T.E. attenuation level, group delay time, etc.Type: GrantFiled: April 24, 1997Date of Patent: June 1, 1999Assignee: NGK Insulators, Ltd.Inventors: Mitsuhiro Tanaka, Susumu Nomoto, Masahiko Sugiyama, Kenji Suzuki
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Patent number: 5905324Abstract: A surface acoustic wave device makes it possible to increase the electrode width without generating mass-electrical-loading and is capable of operating in a high-frequency band higher than or equal to the UHF band, and this surface acoustic way device may be used in a communication device to eliminate need for any down-converter which is indispensable to the conventional high-frequency communication device, and which is therefore capable of being manufactured at a reduced cost. The surface acoustic wave device is provided with an electrode structure meeting conditions represented by: s+m=(2n+1)L/(4k), where L is electrode period, not taking into consideration the polarity of an interdigital transducer, m is electrode line width, s is minimum electrode gap width, and n and k are natural numbers. The surface acoustic wave device is used as the demodulator of the communication device.Type: GrantFiled: August 22, 1995Date of Patent: May 18, 1999Assignee: Hitachi, Ltd.Inventors: Takashi Shiba, Yoshihiro Yamada, Akitsuna Yuhara, Minoru Moteki
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Patent number: 5895996Abstract: A SAW device utilizing elastic surface waves, in which the Q value indicating resonance sharpness is high, and which presents excellent frequency temperature characteristics and short-term frequency stability. In a SAW device according to the present invention, an IDT and two reflectors are in parallel in the propagation direction of the phase of the elastic surface waves. The IDT and reflectors are disposed to cover the power flow direction, which is the propagation direction of energy of the elastic surface waves, whereby the energy of the elastic surface waves is efficiently confined. Moreover, it becomes possible to manufacture the SAW device utilizing a piezoelectric crystal in which angle .theta. and angle .psi. indicating excellent frequency temperature characteristics are 25 to 45 degrees and 40 to 47 degrees, respectively. It is also possible to manufacture the SAW device utilizing a piezoelectric crystal where angle .psi. is related to angle .theta. such that .theta.=2.775.times.(.psi.-32.5)+6.Type: GrantFiled: May 29, 1996Date of Patent: April 20, 1999Assignee: Seiko Epson CorporationInventors: Michiaki Takagi, Eishi Momosaki, Yoshinori Ikusaka
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Patent number: 5891557Abstract: A diamond base material for surface acoustic wave device, which includes: a low-resistivity base material, and a high-resistivity diamond layer having a thickness of 5-50 .mu.m disposed on the low-resistivity base material.Type: GrantFiled: April 15, 1997Date of Patent: April 6, 1999Assignee: Sumitomo Electric Industries, Ltd.Inventors: Shin-ichi Shikata, Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, Akihiro Hachigo
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Patent number: 5892417Abstract: A method for packaging an acoustic wave filter die, and an acoustic wave filter die packaged by the method. The method includes steps of providing an acoustic wave filter die having an active area disposed on a first surface thereof, providing a leadframe including a die flag and sealing the first surface to the die flag. The method also includes steps of molding a plastic package body about the die and the die flag and singulating the plastic body, the die and the die flag. The molding step desirably includes substeps of placing the acoustic wave filter die sealed to the leadframe in a mold, applying a thermosetting plastic material at a suitable temperature less than the glass transition temperature and at a suitable pressure to the acoustic wave filter die sealed to the leadframe in the mold and maintaining the suitable temperature for a suitable period of time.Type: GrantFiled: December 27, 1996Date of Patent: April 6, 1999Assignee: Motorola Inc.Inventors: Gary Carl Johnson, Michael J. Anderson, Gregory Jon Kennison, Jeffrey Eanes Christensen, Mark Phillip Popovich
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Patent number: 5888646Abstract: A surface acoustic wave device comprises a diamond layer (12) or a substrate (11) with a diamond layer (12) formed thereon, an Al electrode (13) formed on the diamond layer (12), and a ZnO piezoelectric thin film layer (14) formed on the diamond layer (12) with the Al electrode (13) covered by the ZnO piezoelectric thin film layer (14). The ZnO piezoelectric thin film layer (14) has a thickness h1 within a range defined by 0.65.ltoreq.kh1.ltoreq.0.75 while the Al electrode (13) has a thickness h2 within a range defined by 0.03.ltoreq.kh2.ltoreq.0.04, where k is given by k=2 .pi./.lambda. and .lambda. represents an electrode period.Type: GrantFiled: February 19, 1997Date of Patent: March 30, 1999Assignees: NEC Corporation, Sumitomo Electric Industries, Ltd.Inventors: Yoshihiro Takahashi, Yasushi Yamamoto, Natsuhiko Sakairi, Shin-Ichi Shikata, Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, Hiroyuki Kitabayashi
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Patent number: 5889446Abstract: A surface acoustic wave device includes a piezoelectric substrate, an interdigital electrode pattern, and a resistor thin film. The piezoelectric substrate has a piezoelectric effect. The interdigital electrode pattern is made of a conductive thin film and formed on the piezoelectric substrate to perform conversion between an electrical signal and a surface acoustic wave. The resistor thin film is formed on the piezoelectric substrate to electrically connect the piezoelectric substrate to the interdigital electrode pattern. The resistor thin film serves to remove charges from a surface of the piezoelectric substrate due to a pyroelectric effect to the interdigital electrode pattern.Type: GrantFiled: January 14, 1997Date of Patent: March 30, 1999Assignee: NEC CorporationInventors: Yoshihiro Yamada, Yasushi Yamamoto
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Patent number: 5889357Abstract: The substrate for devices 10 comprises an insulating substrate 12 of an insulating material, conducting layers 14 formed on the insulating substrate 12 and opposed to each other at a certain distance, and a dielectric film 16 formed on that portion of the insulating substrate 12 between the conducting layers 14. The substrate 10 incorporates a capacitance constituted by the opposed electric layers 14 and the dielectric film 16. A piezoelectric oscillator 20 is connected to the left and right conducting layers 14b, 14c of the substrate for devices 10. A cap 22 is connected to a boundary part of the substrate 10 through epoxy resin 24. The substrate for devices 10 with a built-in capacitance can reduce fabrication costs of a piezoelectric oscillation device and a surface acoustic wave device.Type: GrantFiled: December 6, 1995Date of Patent: March 30, 1999Assignee: Fujitsu LimitedInventors: Masanori Yachi, Takashi Miyagawa, Takayuki Fujii, Masaaki Ono
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Patent number: 5886452Abstract: An SH wave position-sensing device comprising two SH wave transducing units X and Y, a nonpiezoelectric plate and a signal controller. Each unit contains piezoelectric substrates P.sub.T0, P.sub.R0, P.sub.Ti (i=1, 2, . . . , N) and P.sub.Ri (i=1, 2, . . . , N), interdigital transducers T.sub.0, R.sub.0, T.sub.i (i=1, 2, . . . , N) and R.sub.i (i=1, 2, . . . , N). The interdigital transducers T.sub.0, R.sub.0, T.sub.i and R.sub.i, are formed on an upper- or a lower end surface of the piezoelectric substrates P.sub.T0, P.sub.R0, P.sub.Ti and P.sub.Ri, respectively. The lower end surface of each piezoelectric substrate is cemented on an upper end surface of the nonpiezoelectric plate. The finger direction of each interdigital transducer R.sub.i is slanting to that of each interdigital transducer T.sub.i. When an electric signal is applied to the interdigital transducer T.sub.0, an SH wave is excited in a bilayer zone B.sub.T0 formed by the piezoelectric substrate P.sub.Type: GrantFiled: August 1, 1997Date of Patent: March 23, 1999Inventor: Kohji Toda
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Patent number: 5883575Abstract: An RF tag having an antenna for receiving a RF signal having a frequency band between first and second frequencies and an acoustical resonator having a resonant frequency related to the first and second frequencies. The acoustical resonator has first and second electrodes that sandwich a layer of piezoelectric material. The antenna is connected to one of these electrodes. The resonator filters the signal received on the antenna. The filter can function either as a notch filter or as a bandpass filter. A resonator that acts as a bandpass filter includes a third electrode and a second layer piezoelectric material sandwiched between the second electrode and the third electrode. A frequency multiplier circuit may be incorporated in the RF tag to provide a response signal that occupies a frequency band at a frequency above the second frequency. In one embodiment of the present invention, multiple resonators having different resonant frequencies are utilized to generate a response code.Type: GrantFiled: August 12, 1997Date of Patent: March 16, 1999Assignee: Hewlett-Packard CompanyInventors: Richard C. Ruby, Philip Canfield
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Patent number: 5883457Abstract: A touch sensor system, including a substrate, capable of propagating surface acoustic waves; and a reflective array formed on said substrate, said reflective array having a plurality of reflective elements, each reflective element reflecting a portion of an incident surface acoustic wave. The reflective array is formed of an organic matrix. The organic matrix is preferably chemically bonded to the substrate, and is preferably a thermoset resin. The resulting reflective arrays are preferably stable under changes in moisture between 0% and 60% RH at temperatures between about 0.degree.-50.degree. C. The organic matrix can also be used in a humidity or chemical sensor.Type: GrantFiled: April 24, 1997Date of Patent: March 16, 1999Assignee: Raychem CorporationInventors: James A. Rinde, Barry C. Mathews
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Patent number: 5880552Abstract: A water vapor insensitive and corrosion resistant chemical or biochemical nsor device, including a transducer, coated with a protective coating of diamond or a diamond-like carbon, preferably by a pulsed laser deposition technique. The surface of the protective coating is coated with a chemoselective or bioselective absorption material or film.Type: GrantFiled: May 27, 1997Date of Patent: March 9, 1999Assignee: The United States of America as represented by the Secretary of the NavyInventors: Robert Andrew McGill, Paul Christopher Dorsey, Douglas Brian Chrisey
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Patent number: 5877411Abstract: A fluid sensor includes a base body 2 having a vibrating portion 7, a piezoelectric element 3 which is fixed onto one surface of the vibrating portion 7 and has a piezoelectric film 4 and at least a pair of electrodes 5a, 5b which are disposed in contact with the piezoelectric film 4, an electrode terminal 6 which is disposed on the surface of the base body 2 and electrically connected to the pair of electrodes 5a, 5b, a coating material 8 which is disposed on the surface of the base body 2 in the periphery of the electrode terminal 6; pressure plates 14a, 14b, and a sealing member 12 which is held between the base body 2 and the pressure plates 14a, 14b and formed so as to surround the electrode terminal 6, wherein the electrode terminal 6 is held gas-tightly and/or liquid-tightly with respect to a fluid to be measured by holding the sealing member 12 between the coating material 8 and the pressure plates 14a, 14b.Type: GrantFiled: May 16, 1997Date of Patent: March 2, 1999Assignee: NGK Insulators, Ltd.Inventors: Masahiko Namerikawa, Kazuyoshi Shibata, Yukihisa Takeuchi, Shigeki Nakao
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Patent number: 5856720Abstract: In a resonator type surface acoustic wave filter, a fundamental mode of a mode to distribute in a direction perpendicular to propagating direction of a surface acoustic wave (hereinafter referred to as transverse mode) becomes a primary response, whereas a transverse secondary mode becomes spurious. In case of the surface acoustic wave device formed on a piezoelectric substrate having smaller electromechanical coupling factor of a quartz substrate or so forth, it is impossible to obtain sufficient restriction of the second mode spurious. This problem is solved by canceling electrical potential of transverse secondary mode and whereby restricting excitation with a resonator type surface acoustic device formed on a quartz substrate, in which a configuration of an interdigital electrode is selected to establish a ratio of an overlap width of an electrode finger versus an aperture width in a range greater than or equal to 0.75 to smaller than or equal to 0.85.Type: GrantFiled: March 7, 1997Date of Patent: January 5, 1999Assignee: NEC CorporationInventors: Susumu Yoshimoto, Yasushi Yamamoto
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Patent number: 5850118Abstract: An ultrasonic touch-position sensing device comprising a piezoelectric substrate, two surface acoustic wave transducing units X and Y, and a controlling system connected with the units X and Y. The unit X includes interdigital transducers T.sub.X and R.sub.X, and the unit Y includes interdigital transducers T.sub.Y and R.sub.Y on the upper end surface of the substrate. When an electric signal is applied to each of the interdigital transducers T.sub.X and T.sub.Y, a surface acoustic wave is excited on the upper end surface of the substrate. The surface acoustic wave excited by the interdigital transducer T.sub.X and that excited by the interdigital transducer T.sub.Y are transduced to electric signals E.sub.Xi (i=x, . . . , 2, 1, 0, -1, -2, . . . , -x) and E.sub.Yj (j=y, . . . , 2, 1, 0, -1, -2, . . . , -y), respectively. If touching a crossing point made from the position F.sub.Xx and F.sub.Yy, the electric signals E.sub.X-x and E.sub.Y-y are delivered from the interdigital transducers R.sub.X and R.sub.Type: GrantFiled: May 5, 1997Date of Patent: December 15, 1998Inventor: Kohji Toda
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Patent number: 5847486Abstract: An inexpensive Love-wave device having a wide frequency difference between its resonant and antiresonant frequencies includes a Y-cut substrate made from LiNbO.sub.3 for X propagation. An interdigital transducer including a thin film of Ta or W is located on the substrate for exciting a Love wave.Type: GrantFiled: November 13, 1996Date of Patent: December 8, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Michio Kadota, Toshimaro Yoneda, Naoki Mizoguchi
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Patent number: 5847626Abstract: A balanced-type surface acoustic wave filter is provided which can attain a balanced-type of high frequency circuit without connecting a balance-unbalanced conversion circuit.A substrate of tantalic acid lithium substrate with 36 degrees rotation, Y cut, and X propagation is used, and aluminium is used for electrode to form resonators. Then, two resonators in a serial arm and two resonators in a parallel arm are connected in the form of symmetry and lattice to form a balanced-type surface acoustic wave filter. In this configuration, antiresonance frequency in the serial arms and resonance frequency in the parallel arms are substantially equal to each other.Type: GrantFiled: May 29, 1996Date of Patent: December 8, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Yutaka Taguchi, Kazuo Eda, Shun-ichi Seki, Keiji Onishi
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Patent number: 5844347Abstract: A SAW device comprising an inter-digital electrode capable of withstanding application of excessive electric power, while preventing an increase of insertion loss. The SAW device has an inter-digital electrode formed by alternating layers of aluminum films and conductive films, where the conductive films have an elastic constant greater than that of the aluminum films.Type: GrantFiled: August 29, 1996Date of Patent: December 1, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Ryoichi Takayama, Keizaburo Kuramasu, Toshio Sugawa
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Patent number: 5838088Abstract: A surface acoustic wave position-sensing device comprising two surface acoustic wave transducing units, a nonpiezoelectric plate and a controlling system connected with the units. Each unit consists of two piezoelectric substrates, a first group of interdigital transducers (IDTs) and a second group of interdigital transducers (IDTs). The second group of the IDTs is placed such that the finger direction thereof is slanting to that of the first group of the IDTs by an angle .alpha.. The thickness of each piezoelectric substrate is smaller than an interdigital periodicity of the IDTs. The thickness of the nonpiezoelectric plate is larger than three times the interdigital periodicity. When an electric signal is applied to the first group of the IDTs, a SAW is excited in one of the piezoelectric substrates and transmitted to the other of the piezoelectric substrates through the upper end surface of the nonpiezoelectric plate.Type: GrantFiled: March 6, 1997Date of Patent: November 17, 1998Inventor: Kohji Toda
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Patent number: 5837332Abstract: A method and apparatus for preparing thin films, a device, an electronic and magnetic apparatus, an information recording and reproducing apparatus, an information processing apparatus and a crystal preparing method from the molten state. A thin film is prepared as the substrate or the surface of the substrate is being excited and characterized by a device having at least a substrate and a thin film with at least one layer prepared thereon and an electronic and magnetic apparatus having integration of the devices, wherein at least one layer of the thin film is prepared as the surface of the substrate is being excited. The recording and reproducing apparatus for recording and reproducing information is composed of an information memory medium device having a recording layer of the thin film prepared as the surface of the substrate is being excited and a recording head whose core is prepared as the surface of the substrate is being excited.Type: GrantFiled: July 31, 1996Date of Patent: November 17, 1998Assignees: Nihon Victor Kabushiki-kaisha, Kabushiki-kaisha Hitachi SeisakushoInventors: Migaku Takahashi, Katsuya Yokoyama, Jun Yamada, Takashi Shiba
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Patent number: 5838089Abstract: Embedded IDT electrodes are provided in a multilayer structure consisting of a diamond layer on a substrate with IDT electrodes formed on the diamond and a very thin interlayer covering the interdigitated transducer structure and the diamond, thus embedding the IDT electrodes between the diamond layer and the interlayer, with a piezoelectric layer on the interlayer so that an acoustic surface wave propagates in the diamond layer. The very thin interlayer between the diamond and the piezoelectric layer greatly increases the uniformity of the piezoelectric layer but does not interfere with the acoustic properties of a SAW device.Type: GrantFiled: February 18, 1997Date of Patent: November 17, 1998Assignee: Kobe Steel USA Inc.Inventors: David L. Dreifus, Joseph S. Holmes
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Patent number: 5831369Abstract: An encapsulation for SAW components and a method for producing the encapsulation use a cap to seal component structures on a substrate. The cap is in the form of a cover on the substrate and has cutouts which accommodate the component structures in regions of the component structures.Type: GrantFiled: November 4, 1996Date of Patent: November 3, 1998Assignee: Siemens Matsushita Components GmbH & Co. KGInventors: Bruno Furbacher, Friedrich Lupp, Wolfgang Pahl, Gunter Trausch
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Patent number: 5831492Abstract: Selected transducer geometries including unbalanced split electrode and three electrode per wavelength structures are employed for use in wide band tapered SAW devices. Combining geometries useful in narrow bandwidth SAW filters for canceling reflected waves leading to triple transit interference, and electrode tapering useful in wide bandwidth SAW filters for permitting transduction of a wide range of surface acoustic wavelengths has the unexpected result of significantly reducing insertion loss and improving triple transit suppression over wider bandwidths than can be achieved with SPUDT designs on non-tapered devices. The interdigitized electrode fingers of opposing bus bars in the transducer have a tapered alignment wherein a period of electrode finger portions along an acoustic wave propagation axis decreases along a transducer dimension.Type: GrantFiled: September 15, 1995Date of Patent: November 3, 1998Assignee: Sawtek Inc.Inventor: Leland P. Solie
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Patent number: 5821665Abstract: A compact, low height, low cost, and high reliability surface acoustic wave device, and its method of manufacture. The surface acoustic wave device consists of a substrate, a comb-electrode disposed on the main surface of the substrate, plural electrode pads disposed around the comb-electrode, protecting means covering the comb-electrode through a closed space produced by combining the comb-electrode and the electrode pads with the substrate by using substantially covalent bonding force acting between conductive bumps formed on the electrode bumps, a conductive adhesive layer disposed at least on the top of the conductive bumps, and a package adhered on the conductive bumps by means of the conductive adhesive, and insulation adhesive filled into the package contacting the conductive adhesive, the conductive bumps and the protective means.Type: GrantFiled: May 8, 1996Date of Patent: October 13, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Keiji Onishi, Shun-ichi Seki, Yutaka Taguchi, Kazuo Eda
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Patent number: 5817922Abstract: In a gas sensor comprising a housing and having driver and amplifier circuits the housing has a bottom part with at least four cavities arranged in radial symmetry around a central gas admission space from which gas admission passages of the same shape and size extend radially outwardly to the various cavities for supplying gas to be measured to surface wave components of which one is disposed in each of the cavities and the cavities have discharge passages extending outwardly and having all the same gas flow resistance for the discharge of the gases from the housing cavities.Type: GrantFiled: November 15, 1996Date of Patent: October 6, 1998Assignee: Forschungszenlram Karlsruhe GmbHInventors: Michael Rapp, Achim Voigt
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Patent number: 5818146Abstract: A SAW resonator filter apparatus includes attenuation characteristics which are steep in a frequency region from a pass band to a higher-frequency stop band without experiencing an increase in insertion losses and enlargement of the apparatus. First, second and third SAW resonator filters are disposed on a piezoelectric substrate and are connected in a cascade arrangement to each other. The first and third SAW resonator filters have interdigital electrodes formed of solid electrode fingers, while the second SAW resonator filter disposed between the first and third filters has interdigital electrodes formed of split electrode fingers. With this construction, the steep attenuation characteristics of the response in a higher frequency range appearing in the frequency characteristics of the second SAW resonator filter can be combined with the attenuation characteristics from the pass band to a higher-frequency stop band of the first and third SAW resonator filters.Type: GrantFiled: December 27, 1996Date of Patent: October 6, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Toru Kurahashi, Kazunobu Shimoe
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Patent number: 5818145Abstract: A surface acoustic wave device of the present invention includes piezo-electric substrates 1 and 2 each having one surface formed with interdigital electrodes 12A, 12B, for transmission and receiving of surface acoustic waves, are received in a casing including a stem 4, a seal ring 9 and a cover plate 5, etc. The piezo-electric substrates 1 and 2 are arranged such that the one surfaces thereof face each other with a predetermined space therebetween and electrically conductive members 3 are disposed between the piezo-electric substrates 1 and 2. The electrically conductive members 3 may be gold bumps, solder bumps, metal balls of such as solder or copper, electrically conductive adhesive members or electrically conductive rubber members, etc. The surface acoustic wave device is applicable to such as filters and featured by having small mounting area and easiness of manufacture.Type: GrantFiled: April 9, 1996Date of Patent: October 6, 1998Assignee: NEC CorporationInventor: Eiichi Fukiharu
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Patent number: 5814917Abstract: Aluminum is used for the interdigital transducer mounted on a piezoelectric substrate to realize a surface acoustic wave transducer having a small capacity ratio, no spurious resonance, and a low loss. A .theta. rotated Y cut lithium niobate single crystal piezoelectric substrate is used for the piezoelectric material, a metal film of which principal ingredient is aluminum is used for the interdigital transducer, the direction of the interdigital transducer is made parallel to the X-axis of the lithium niobate single crystal, and thick h and electrode pitch P of the interdigital transducer have the following relationship:(.theta.+5).sup.2 /300+11/12.ltoreq.h/P.times.100-8.ltoreq.-0.0001.times.(.theta.+5).sup.3 +0.1625.times.(.theta.+5)+5.5and-30.ltoreq..theta..ltoreq.20.Type: GrantFiled: July 10, 1996Date of Patent: September 29, 1998Assignee: Hitachi Media Electronics Co., Ltd.Inventors: Atsushi Isobe, Mitsutaka Hikita, Chisaki Takubo, Kengo Asai
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Patent number: 5814918Abstract: The present invention directed to a SAW device comprising a diamond layer a ZnO layer and an SiO.sub.2 layer, which can be operated at the frequency of 2 GHz or higher, with superior durability and less energy loss. The SAW device for 2nd mode surface acoustic wave of a wavelength .lambda. (.mu.m) according to the present invention comprises: (i) a diamond layer, (ii) a ZnO layer formed on the diamond layer, the ZnO layer having a thickness t.sub.z, (iii) an interdigital transducer (IDT) formed over the ZnO layer, and (iv) a SiO.sub.2 layer formed over the interdigital transducer onto the ZnO layer, the SiO.sub.2 layer having a thickness of t.sub.s ; wherein parameters kh.sub.z =(2.pi./.lambda.)t.sub.z and kh.sub.s =(2.pi./.lambda.)t.sub.s are given within a region A-B-C-D-E-F-G-H-I-J-K-L-M-N-O-P-Q-R-A in a two-dimensional Cartesian coordinate graph having abscissa axis of kh.sub.z and ordinate axis of kh.sub.Type: GrantFiled: August 7, 1996Date of Patent: September 29, 1998Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, Hiroyuki Kitabayashi, Shinichi Shikata
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Patent number: 5814525Abstract: A piezoelectric biosensor substrate useful for immobilizing biomolecules in an oriented manner on the surface of a piezoelectric sensor has a ladder polymer of polyacrylonitrile. To make the substrate, a solution of an organic polymer, preferably polyacrylonitrile, is applied to the surface of a piezoelectric sensor. The organic polymer is modifying by heating the polymer in a controlled fashion in air such that a ladder polymer is produced which, in turn, forms the attachment point for the biomolecules comprising the piezoelectric biosensor.Type: GrantFiled: January 25, 1996Date of Patent: September 29, 1998Assignee: Sandia CorporationInventors: Clifford L. Renschler, Christine A. White, Robert M. Carter
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Patent number: 5801474Abstract: A surface acoustic wave (SAW) device in accordance with the present invention is constituted in such a way that a SAW device chip 2 in which electrode patterns are formed is accommodated within a package composed of a ceramic board 1 and a metallic cap 4. The SAW device comprises metallic patterns 5a and 5b provided at the ceramic board 1 as input/output terminals of the package and having convex portions 6a and 6b connected electrically to bonding pads 8a and 8b of a SAW device chip, respectively, and an elastic body 3 arranged between the metallic cap 4 and the SAW device chip 2. The SAW device chip 2 is fixed such that the bonding pads 8a and 8b are pushed against the convex portions 6a and 6b under a predetermined contact pressure by elastic force of the elastic body 3.Type: GrantFiled: December 6, 1995Date of Patent: September 1, 1998Assignee: NEC CorporationInventor: Natsuhiko Sakairi
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Patent number: 5798597Abstract: A surface acoustic wave position-sensing device comprising a piezoelectric substrate, a nonpiezoelectric plate, two surface acoustic wave transducing units and a controlling system connected with the units. Each unit consists of interdigital transducers (IDTs). The thickness of the piezoelectric substrate is larger than three time an interdigital periodicity of the IDTs. The thickness of the nonpiezoelectric plate is smaller than the interdigital periodicity. Each of the IDTs is placed such that the finger direction thereof is slanting to that of the IDTs by an angle .alpha.. When an electric signal is applied to each of the IDTs a SAW is excited on an area, and transmitted to an area, in contact with the IDTs of the upper end surface of the piezoelectric substrate through the nonpiezoelectric plate. The controlling system senses a touch with a finger by the generation of the electric signal at one of the interdigital transducers.Type: GrantFiled: March 6, 1997Date of Patent: August 25, 1998Inventor: Kohji Toda
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Patent number: 5796205Abstract: A SAW (Surface Acoustic Wave) device includes a piezoelectric member, a heat-treated ion implantation layer formed in a surface portion of the piezoelectric member, and an electrode of a comb type resonator with reflectors provided on said heat-treated ion implantation layer. The present invention also provides a method of producing such a SAW device.Type: GrantFiled: March 14, 1996Date of Patent: August 18, 1998Assignee: Fujitsu LimitedInventors: Tokihiro Nishihara, Takashi Matsuda, Hidema Uchishiba, Osamu Ikata, Yoshio Satoh, Kazunari Komenou
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Patent number: 5793147Abstract: An end face reflection type surface wave resonator utilizing SH type surface waves capable of providing a plurality of resonance characteristics is formed as a single element. In the surface wave resonator, surface waves are reflected between two opposite end faces of a piezoelectric substrate. The surface wave resonator has IDTs that form first and second resonant units. The distance L between the two end faces is selected to be within a range expressed by (.lambda..sub.1 /2).times.N.sub.1 .+-.(.lambda..sub.1 /20) (N.sub.1 is an integral number) where .lambda.1 represents the wavelength of a surface wave excited by the first resonant unit. The distance L is chosen to be out of a range expressed by (.lambda..sub.2 /2).times.N.sub.2 .+-.(.lambda..sub.1 /20) (N.sub.2 is an integral number) where .lambda..sub.2 represents the wavelength of a surface wave excited by the second resonant unit.Type: GrantFiled: April 22, 1997Date of Patent: August 11, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Michio Kadota, Kazuhiko Morozumi
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Patent number: 5783896Abstract: A first surface acoustic wave device for 2nd mode surface acoustic wave of a wavelength .lambda. (.mu.m) according to the present invention is a SAW device of "type A" device shown in FIG. 6A, wherein a parameter kh3=2.pi.(t.sub.A /.lambda.) is: 0.033.ltoreq.kh3.ltoreq.0.099, and wherein a parameter kh1=2.pi.(t.sub.z /.lambda.) and a parameter kh2=2.pi.(t.sub.s /.lambda.) are given within a region ABCDEFGHIJKLA in a two-dimensional Cartesin coordinate graph of FIG. 1.Type: GrantFiled: January 31, 1997Date of Patent: July 21, 1998Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, Hiroyuki Kitabayashi, Shin-ichi Shikata
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Patent number: 5777419Abstract: A piezoelectric substrate (120) and a method for preparing same. The method includes steps of (i) providing a boule of piezoelectric material, (ii) orienting the boule to Euler angles chosen to provide a boundary condition matched to a partially-metallized surface and (iii) sawing the boule into at least a first slice (120) having first and second surfaces, at least one of the first and second surfaces comprising a planar surface. The method desirably but not essentially further includes steps of (iv) polishing at least one of the first and second surfaces to provide a substantially planar polished surface, (v) disposing a layer of metal on the at least one of the first and second surfaces and (vi) patterning the layer of metal to provide at least one interdigitated pattern (105, 110) comprising an acoustic wave transducer (105, 110), the acoustic wave transducer (105,110) providing the boundary condition matched to a partially-metallized surface.Type: GrantFiled: January 15, 1997Date of Patent: July 7, 1998Assignee: Motorola Inc.Inventor: David Penunuri
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Patent number: 5777422Abstract: The present invention directed to a SAW device comprising a diamond layer thinner ZnO layer, which can be operated at higher frequency, with superior characteristics including less energy loss. The first SAW device according to the present invention comprises a layer constitution shown in FIG. 23, wherein, for 0th mode surface acoustic wave having a wavelength .lambda., a parameter kh3 =(2.pi./.lambda.)t3 satisfies: 0.0470.ltoreq.kh3.ltoreq.0.0625, and wherein a parameter kh1 =(2.pi./.lambda.)t1 and a parameter kh2=(2.pi./.lambda.)t2 are given within a region A-B-C-D-E-F-A in a two-dimensional Cartesian coordinate graph having ordinate axis of the kh1 and abscissa axis of kh2, the outer edge of the region A-B-C-D-E-F-A being given by a closed chain in the Cartesian coordinate, consisting of points A, B, C, D, E, and F, and lines A-B, B-C, C-D, D-E, E-F and F-A, as shown in a two-dimensional Cartesian coordinate graph of FIG. 3.Type: GrantFiled: September 27, 1996Date of Patent: July 7, 1998Assignee: Sumitomo Electric Industries, Ltd.Inventors: Hiroyuki Kitabayashi, Hideaki Nakahata, Kenjiro Higaki, Satoshi Fujii, Shin-ichi Shikata
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Patent number: 5771206Abstract: An elastic wave position-sensing device comprising a piezoelectric substrate, an input interdigital transducer T formed on an upper end surface of the piezoelectric substrate, and an output interdigital transducer R formed on the upper end surface of the piezoelectric substrate such that the finger direction of the interdigital transducer R is slanting to that of the interdigital transducer T by an angle .alpha.. The thickness d of the piezoelectric substrate is smaller than an interdigital periodicity P of the interdigital transducer T. An interdigital periodicity P.sub.N along the vertical direction to the finger direction of the interdigital transducer R is equal to the product of the interdigital periodicity P and cos .alpha.. An overlap length L.sub.P along the finger direction of the interdigital transducer R is equal to the product of an overlap length L of the interdigital transducer T and sec .alpha..Type: GrantFiled: March 6, 1997Date of Patent: June 23, 1998Inventor: Kohji Toda
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Patent number: 5770985Abstract: A surface acoustic wave (SAW) filter includes a plurality of interdigital transducers located on a piezoelectric substrate along a surface wave propagation direction, at least a single one-port SAW resonator being connected in parallel with an output side of the SAW filter, while the resonance frequency (f.sub.0) of the SAW resonator is set in frequency region level which is lower than the pass band of the SAW filter.Type: GrantFiled: June 27, 1996Date of Patent: June 23, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Tadamasa Ushiroku, Hideharu Ieki
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Patent number: 5767604Abstract: An elastic wave position-sensing device comprising two elastic wave transducing units X and Y, a nonpiezoelectric plate, and a controlling system connected with the units X and Y. Each unit consists of a piezoelectric substrates P.sub.T and P.sub.R, interdigital transducers T.sub.0 and T.sub.i (i=1, 2, . . . , N) formed on one end surface of the piezoelectric substrate P.sub.T, interdigital transducers R.sub.0, R.sub.i1 and R.sub.i2 (i=1, 2, . . . , N) placed on one end surface of the piezoelectric substrate P.sub.R. Each of the interdigital transducers R.sub.i1 and R.sub.i2 is placed such that the finger direction thereof is slanting to that of the interdigital transducer T.sub.i by an angle .alpha.. The thickness d of the piezoelectric substrates P.sub.T and P.sub.R is smaller than an interdigital periodicity P of the interdigital transducers T.sub.0, T.sub.i and R.sub.0. The thickness of the nonpiezoelectric plate is smaller than two times the thickness d, the piezoelectric substrates P.sub.T and P.sub.Type: GrantFiled: March 6, 1997Date of Patent: June 16, 1998Inventor: Kohji Toda
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Patent number: 5767608Abstract: A surface acoustic wave (SAW) position-sensing device comprising a piezoelectric substrate, an input interdigital transducer (IDT) T formed on an upper end surface of the piezoelectric substrate, and an output IDT R formed on the upper end surface of the piezoelectric substrate such that the finger direction of the IDT R is slanting to that of the IDT T by an angle .alpha.. The thickness d of the piezoelectric substrate is larger than three times an interdigital periodicity P of the IDT T. An interdigital periodicity P.sub.N along the vertical direction to the finger direction of the IDT R is equal to the product of the interdigital periodicity P and cos .alpha.. An overlap length L.sub.P along the finger direction of the IDT R is equal to the product of an overlap length L of the T and sec .alpha.. When an electric signal is applied to the IDT T, the SAW is excited on the upper end surface of the piezoelectric substrate, and is transducer to electric signals E.sub.j with phases .theta..sub.Type: GrantFiled: March 6, 1997Date of Patent: June 16, 1998Inventor: Kohji Toda
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Patent number: 5767603Abstract: A single-chip piezoelectric resonator using SH type surface waves has an interdigital transducer formed on a piezoelectric substrate. The interdigital transducer is designed to have two or more resonance characteristics, for example, by using a pair of thinned-out comb-shaped electrodes with mutually interlocking fingers protruding towards each other. Such an interdigital transducer may be formed also by using a pair of comb-shaped electrodes with the lengths of their mutually pointing fingers varied. A trap circuit with two sufficiently separated trap frequencies and improved attenuation characteristics at these two trap frequencies can be formed by forming two interdigital transducers of the kind described above on a single piezoelectric substrate so as to provide two resonant units each having two resonance characteristics. Alternatively, two piezoelectric resonators of the kind described above may be connected in parallel to provide two resonance characteristics.Type: GrantFiled: November 6, 1996Date of Patent: June 16, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Michio Kadota, Junya Ago, Kazuhiko Morozumi
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Patent number: 5760524Abstract: A surface acoustic wave (SAW) device (300) is formed from a leaky wave mode piezoelectric substrate (310) to have substantially reduced surface wave attenuation when operating at a particular frequency. The SAW device (300) includes a SAW pattern (322, 324), disposed on a surface (321) of the piezoelectric substrate, having a free surface portion (324) and a shorted surface portion (322). The SAW pattern (322, 324) is overlaid with a material (330), preferably glass, which has a thickness selected to reduce surface wave attenuation.Type: GrantFiled: September 3, 1996Date of Patent: June 2, 1998Assignee: Motorola, Inc.Inventors: Robert J. Higgins, Jr., Fred S. Hickernell
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Patent number: 5760526Abstract: A plastic molded SAW device (50) is provided by flip-chipping a SAW die (28) onto a die flag (16) of a lead frame (10) and attaching the two (28, 10) together by an annular ring (26, 60, 62) of an insulating material or other solder, so that an active central portion (52) of the SAW die (28) faces the die flag (16) but is separated therefrom. Electrical contacts to the circuitry on the SAW die (28) are made, most conveniently by solder bumps (36) which seal to electrode fingers (18) on the lead frame (10). This provides a very small sealed void (40, 74, 82) immediately above the active portion (52) of the SAW die (28) so that the attached die (28) and lead frame (10) combination can be over molded with plastic encapsulant (38) without such plastic encapsulant (38) coming in contact with the active region (52) of the SAW die surface (42).Type: GrantFiled: April 3, 1995Date of Patent: June 2, 1998Assignee: Motorola, Inc.Inventor: Michael John Anderson
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Patent number: 5736267Abstract: A transparent conductive film of a zinc oxide type containing gallium and silicon, which contains silicon in an amount of from 0.01 to 1.5 mol % in terms of SiO.sub.2.Type: GrantFiled: August 16, 1995Date of Patent: April 7, 1998Assignee: Asahi Glass Company Ltd.Inventors: Akira Mitsui, Kazuo Sato, Masami Miyazaki, Junichi Ebisawa, Yasuo Hayashi, Masao Higeta, Katsuaki Aikawa, Atsushi Hayashi
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Patent number: 5734332Abstract: An identification device is provided which includes an inactive code carrier, such as a standing acoustic wave component, a frequency mixing section, and a double antenna input. Each of the antennas are tuned to a separate predetermined transmitted signal wherein the frequencies are different. The two separately received RF frequencies are mixed to produce an intermediate frequency having the sum or difference of the two received frequencies. The intermediate frequency is coupled to the standing acoustic wave device which applies a coded signal to the intermediate frequency. The intermediate frequency is then recombined with one of the original incoming RF frequencies to be retransmitted from the identification device. The mixer section can include a diode and a coil for matching the impedance of the incoming signal with the inactive code carrier.Type: GrantFiled: March 30, 1995Date of Patent: March 31, 1998Assignee: Micro Design ASInventor: Steffen Kirknes