Abstract: A surface acoustic wave device having a lithium tatraborate single crystal substrate is proposed. An electro-mechanical coupling coefficient K.sup.2 of the substrate is about 1% so as to obtain a surface acoustic wave having sufficient practical energy. When cut angles of the substrate and a propagation direction of the surface acoustic wave are expressed by Eulerian angles (90+.lambda., 90.degree., 90.degree.), a thickness t of an electrode formed on the substrate falls within a region bounded by a dotted curve and an alternate long and short dash curve in FIG. 8. The dotted curve and the alternate long and short dash curve indicate the experimental relationship between the cut angle .lambda. and the thickness t when the TCD is set at 5 and -5 ppm/.degree.C., respectively. When the film thickness t is set within the above-mentioned range, the absolute value of the TCD is set at 5 ppm/.degree.C. or less. When the cut angle .lambda. is 25.degree., the TCD of the substrate becomes zero.

Abstract: Acoustic Wave Devices comprise lithium niobate substrates 6, 22 having the principal plane cut at zero degrees and 128.degree., respectively, with respect to the Y crystallographic axis thereof, propagating in the X direction, with amorphous silicon dioxide surface layers of 0.42 and 1.24 wavelengths, respectively.

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.

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.

Abstract: A broad band surface acoustic wave (SAW) device has an edge-deposited transducer (EDT) capable of frequencies in excess of 1 GHz and bandwidths in the hundreds of MHz. The device includes a transducer on a semiconductor substrate which is either non-piezoelectric or weakly piezoelectric. The substrate has a sharp, smooth edge formed by the intersection of its top and a side surface. The transducer includes a passivation layer deposited on the side surface of the substrate and a starter layer deposited on the passivation layer; an inner metallic (gold, for example) electrode deposited on the starter layer; a transducer layer deposited on the inner metallic electrode; and an outer metallic electrode deposited on the transducer layer. The outer electrode is formed on the transducer layer one-fifth wavelength below the top surface of the substrate.

Abstract: Surface acoustic wave bandpass transversal filters, e.g. television intermediate frequency filters, comprising a +.theta..degree. rotated Y-cut X-propagating lithium niobate substrate with .theta. in the range from 121.degree. to 127.degree., preferably 123.degree. to 125.degree.. For a suitable range of filter bandwidths (35 db bandwidth between 0.05 and 0.5) these substrates provide reduced degradation of the filter upper stopband predominantly due to indirect bulk shear waves in the frequency range from the passband up to the frequency where direct bulk longitudinal wave degradation becomes significant. This frequency range is 41.5 MHz to approximately 55 MHz for a U.K. system t.v. i.f. filter and is 60.25 MHz to approximately 90 MHz for a Japanese system t.v. i.f. filter.

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.

Abstract: Temperature stable cuts of quartz comprise the families of doubly rotated cuts defined by (YXwlt) 0/27/138, 7/27/135.5, 15/40/40, 15/30/38, 12.5/35/130 and rotational equivalents thereof. It is found that SAW devices may be fabricated on these cuts which demonstrate a very high degree of temperature stability and which have other characteristics consistent with practical usage. The sensitivity of the stability to variations in the propagation direction, corresponding to the angle psi, is such that it is advantageous to fabricate several input-output transducer pairs, each slightly rotated with respect to the others, and to chose the most stable for actual use.

Abstract: A quartz crystal plate (L) is used in determining the frequency of a frequency generator, and the frequency determined by said plate is variable as a function of temperature. The quartz plate constitutes the substrate for a surface acoustic wave device, e.g. a resonator or a delay line using comb transducers (1 & 2). The orientation in the quartz crystal of the plane over which the acoustic wave propagates, and the direction of propagation in said plane are defined in terms of a doubly rotated frame of reference as follows: the plate being a double rotation cutting plate defined by yxwl: .phi./.theta., one large surface of which is used for the propagation of a surface wave whose direction of propagation makes an angle .psi. with the second axis of rotation, where the first angle .phi. lies in the range 9.degree.24' to 13.degree.24', the second angle .theta. lies in the range 57.degree.24' to 61.degree.24', and the angle .psi. lies in the range 33.degree. to 37.degree..

Abstract: A broadband electromagnetic acoustic transducer is disclosed for use with an electrically conductive object. The transducer includes a source of magnetic flux for establishing a static magnetic field in the object and an electrical conductor for inducing eddy currents in the object when an alternating current is applied to the conductor. The magnetic field and the conductor are oriented so that the vector product of the magnetic field and the eddy currents produces an instantaneous force field in the object which is periodically alternately directed with a logarithmic periodicity. The source of magnetic flux may be provided by a plurality of alternately oriented magnets aligned along a propagation direction. Alternatively, the conductor may be a serpentine conductor with a plurality of parallel elements which are perpendicular to a propagation direction, the ratio of adjacent spacings between the elements being constant.

Abstract: The invention relates to elastic surface wave pressure gauges.The gauge comprises a plate on which are located the electronic components of the gauge and a pressure sensor grouping the electromechanical elements on a header having connecting pins. The header is provided with a pressure inlet which traverses the plate.The invention is also applicable to the measurement of the pressures of fluids in order to optimize the supply to internal combustion engines. The pressure inlet is made of a rigid metal header and separately grounded for shielding of the surface acoustic wave electrodes to prevent "pull-in" where the oscillators inadvertantly lock on the same frequency.

Abstract: Surface acoustic wave devices with selectable performance parameters such as having a temperature coefficient of zero, may be fabricated employing a monocrystalline semiconductor substrate with a combination of appropriate doping and crystallographic orientation both with respect to the surface and the direction of propagation. Monocrystalline silicon doped with phosphorous to the order of 2.times.10.sup.19 atoms per cc, exhibits a zero temperature coefficient at 300.degree. Kelvin for acoustic waves propagating in the [110] crystallographic direction on a [110] substrate.

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.

Abstract: Temperature compensation is provided to a surface acoustic wave device including acoustoelectric transducers (12, 14) formed on a surface of a gallium arsenide substrate (10), by a composite layer including silicon dioxide (18, 26) and a mass loading metal (20, 24), which may be gold, titanium and gold, or other metals having Rayleigh wave velocities lower than that of gallium arsenide, such as silver and platinum.

Abstract: A piezoelectric single crystal which has a composition represented by a general formula (Ba.sub.2-x Sr.sub.x)TiSi.sub.2 O.sub.8, the value x lying within a range of 0.25.ltoreq.x.ltoreq.1.2; and a surface acoustic wave element which is so constructed as to employ surface waves that propagate on a cut plane perpendicular to the Z-axis of the single crystal, or surface waves that propagate in a specified direction on a cut plane containing the X-axis of the single crystal. The piezoelectric single crystal and the surface acoustic wave element employing it have the merits that the electromechanical coupling factor of the surface acoustic waves is great and that the temperature coefficient of delay time of the surface acoustic waves is small.

Abstract: Surface acoustic wave devices such as reflective array compressors which utilize orthogonal propagation directions are improved by employing a substrate member the surface acoustic wave propagation surface of which exhibits zero temperature coefficient of delay in two orthogonal directions. Temperature compensation means are eliminated and improved performance in relaized by aligning the principal and secondary axes of propagation of the device with the zero temperature coefficient of delay directions. A single cut quartz substrate having its propagation surface defined by a plane coinciding with the Euler angles lambda=0.0.degree.; mu=125.87 (+1-6).degree., theta=45.0.degree. enables realization of the concept with reflective array compressors and other reflective quartz devices.

Abstract: A surface acoustic wave (SAW) device is provided with short-term and long-term stability by recessing the electrode structure into the surface of the piezoelectric crystal of the device. In addition, the surface is passivated with the silicon polymer, and a cover of the same crystalline material is placed above the electrode structure to prevent absorption of impurities into the surface from the atmosphere. The passivation is believed to reduce the effect of thermal agitation of the bonds of the crystal lattice structure, and thereby prevent the making and breaking of chemical bonds with hydroxyl ions that may have been entrapped from the atmosphere. The SAW device is particularly useful in the construction of stable oscillator circuits wherein the passivation provides improved short-term frequency stability and the cover provides long-term frequency stability.

Abstract: There is hereinafter described an integral transducer geometry which provides for the angle of an acoustic wave beam, interacting with an optical beam, to be varied as a continuous function of the transducer drive energy frequency whereby the efficiency of optical beam deflection remains constant over a large bandwidth.

Abstract: An elastic surface wave device includes a transducer having an elastic surface wave propagated in the direction of 75 to 133 degrees to a Y-axis on an X-cut lithium tantalate (LiTaO.sub.3) substrate.

Abstract: A surface acoustic wave device comprising a piezoelectric substrate which comprises an .alpha.-alumina layer as a base region and a zinc oxide layer as a surface region formed on the .alpha.-alumina layer. Preferably the two layers are each made of a single crystal, and the thickness of the zinc oxide layer and an angle between a crystallographic axis of the zinc oxide single crystal and the direction of wave propagation are determined so as to fall within optimum ranges, respectively. This device features an increased phase velocity and an augmented value for the electromechanical coupling coefficient and accordingly is of use at very-high to ultra-high frequencies.

Abstract: A series of lead potassium niobate substrates having X-cut crystallographic orientations defined by the Euler Angles Lambda=90.0.degree., Mu=90.0.degree. and Theta from -10.6.degree. to +10.6.degree..

Abstract: Piezoelectric crystalline film on a substrate, which is a crystalline zinc oxide film with a hexagonal crystal structure and a c-axis substantially perpendicular to the substrate surface, the crystalline zinc oxide film containing, as an additive element, uranium. The piezoelectric crystalline films have high resistivity and a smooth surface, and make it possible to produce piezoelectric transducers with good conversion efficiency. Such films are made by sputtering zinc oxide and uranium onto a substrate from a film material source consisting essentially of a ceramic of zinc oxide containing uranium.

Abstract: A surface acoustic wave resonator includes a base plate made of glass and a layer of piezoelectric material which has a plurality of strips extending parallel to each other for forming a reflector. A surface acoustic wave excited from a transducer reflects at each of the strips. The reflectance of such surface acoustic wave is improved by the arrangement of the strips and the thickness of the layer. On the other hand, the temperature coefficient of the resonance frequency is also improved by the arrangement of the strips and the thickness of the layer, and by the amount of the alkali metal oxide contained in the base plate, and further by the thickness of silicon oxide film laminated on the surface of the base plate.