Abstract: An ultrasonic transducer device comprising: an ultrasonic transducer array micromachined on a substrate; flexible electrical connections connected to the transducer array; and a body of acoustically attenuative material that supports the substrate and the flexible electrical connections. The acoustic backing material may contain additional features, such as tabs or notches, for use in positioning the transducer on fixtures during manufacturing or positioning the transducer within a housing during final assembly. Tabs or other features that are used only during manufacturing may be subsequently removed from the device. The MUT device itself may also be thinned so as to provide flexibility as desired. The backing material is preferably matched in acoustic impedance to the silicon wafer so as to prevent reflection at the interface of any acoustic energy propagating rearward, i.e., in the direction away from the device front surface.

Abstract: Methods for preparing a multi-layer acoustic transducer with reduced total electrical impedance. The methods are based on the stacking of individual piezoelectric layers with metallized surfaces to form a plate in which the metal layers are electrically connected to form interdigitated electrodes. The total electrical impedance of a multi-layer stack comprised of piezoelectric layers connected in this manner is inversely related to the square of the number of layers in the stack. This provides for better matching of the acoustic stack impedance to that of the electrical cable and improved acoustic element sensitivity.

Abstract: A method for manufacturing a multi-layer acoustic transducer with reduced total electrical impedance. The method is based on the bonding of two piezoelectric ceramic layers with confronting metallized surfaces to a thin electrical conductor, then electrically connecting the top and bottom surfaces to form a wrap-around electrode while a center conductor forms a second electrode. The total electrical impedance of a two-layer ceramic stack comprised of piezoelectric layers connected in this manner is one-fourth that of a solid ceramic element of the same size. This provides for better matching of the acoustic stack impedance to that of the electrical cable, increased penetration depth for imaging within the body, and improved acoustic element sensitivity.

Abstract: A method for bonding one surface to a gold surface comprises the following steps: (a) mixing a solution containing sulfur-containing alkoxysilane; (b) treating the gold surface with the solution; (c) adding sulfur-containing alkoxysilane to an adhesive material; (d) applying the adhesive material with additive on one of both surfaces; and (e) pressing the surfaces against each other while the adhesive material therebetween sets.

Abstract: In an ultrasonic transducer, the transducer elements are electrically connected to the pulsers via throughholes in an acoustic backing layer. Electrically conductive material is deposited on the front face of the acoustic backing layer and later diced to form conductive pads, and on the walls of the throughholes or vias to form conductive traces having exposed ends that will be connected later to a printed circuit. The holes in the acoustic backing layer are then filled with acoustic attenuative material. The signal electrodes on the rear faces of the transducer elements are electrically connected to the printed circuit via the conductive pads and the conductive traces of the acoustic backing layer. A common ground connection is disposed between the front faces of the transducer elements and the acoustic impedance matching layer, which ground connection exits the transducer pallet from the side.

Abstract: A method for manufacturing a multi-layer acoustic transducer with reduced total electrical impedance. The method is based on the bonding of two piezoelectric ceramic layers with confronting metallized surfaces to a thin electrical conductor, then electrically connecting the top and bottom surfaces to form a wrap-around electrode while a center conductor forms a second electrode. The total electrical impedance of a two-layer ceramic stack comprised of piezoelectric layers connected in this manner is one-fourth that of a solid ceramic element of the same size. This provides for better matching of the acoustic stack impedance to that of the electrical cable, increased penetration depth for imaging within the body, and improved acoustic element sensitivity.

Abstract: RD-28,709 22An ultrasonic transducer device comprising: an ultrasonic transducer array micromachined on a substrate; flexible electrical connections connected to the transducer array; and a body of acoustically attenuative material that supports the substrate and the flexible electrical connections. The acoustic backing material may contain additional features, such as tabs or notches, for use in positioning the transducer on fixtures during manufacturing or positioning the transducer within a housing during final assembly. Tabs or other features that are used only during manufacturing may be subsequently removed from the device. The MUT device itself may also be thinned so as to provide flexibility as desired. The backing material is preferably matched in acoustic impedance to the silicon wafer so as to prevent reflection at the interface of any acoustic energy propagating rearward, i.e., in the direction away from the device front surface.

Abstract: A method of making an electrical connection between a pair of electrically conductive surfaces, comprising the steps of: placing an electrically conductive (e.g., metal) mesh and a mass of adhesive material between a pair of mutually opposing electrically conductive surfaces; pressing the electrically conductive surfaces together with the mesh and adhesive material therebetween with sufficient pressure that the mesh contacts the opposing electrically conductive surfaces; and curing the adhesive material while pressing the electrically conductive surfaces together. In an ultrasonic transducer, electrically conductive mesh can be placed between a metallized rear surface of a piezoelectric ceramic layer and a printed circuit on a dielectric substrate. Alternatively, the mesh can be placed between opposing metallized surfaces of a piezoelectric ceramic layer and an acoustic backing layer, with electrical conductors being passed through the acoustic backing-layer for connection to a printed circuit.

Abstract: RD-28,709 22An ultrasonic transducer device comprising: an ultrasonic transducer array micromachined on a substrate; flexible electrical connections connected to the transducer array; and a body of acoustically attenuative material that supports the substrate and the flexible electrical connections. The acoustic backing material may contain additional features, such as tabs or notches, for use in positioning the transducer on fixtures during manufacturing or positioning the transducer within a housing during final assembly. Tabs or other features that are used only during manufacturing may be subsequently removed from the device. The MUT device itself may also be thinned so as to provide flexibility as desired. The backing material is preferably matched in acoustic impedance to the silicon wafer so as to prevent reflection at the interface of any acoustic energy propagating rearward, i.e., in the direction away from the device front surface.

Abstract: In an ultrasonic transducer, the transducer elements are electrically connected to the pulsers via throughholes in an acoustic backing layer. Electrically conductive material is deposited on the front face of the acoustic backing layer and later diced to form conductive pads, and on the walls of the throughholes or vias to form conductive traces having exposed ends that will be connected later to a printed circuit. The holes in the acoustic backing layer are then filled with acoustic attenuative material. The signal electrodes on the rear faces of the transducer elements are electrically connected to the printed circuit via the conductive pads and the conductive traces of the acoustic backing layer. A common ground connection is disposed between the front faces of the transducer elements and the acoustic impedance matching layer, which ground connection exits the transducer pallet from the side.

Abstract: A method of making an electrical connection between a pair of electrically conductive surfaces, comprising the steps of: placing an electrically conductive (e.g., metal) mesh and a mass of adhesive material between a pair of mutually opposing electrically conductive surfaces; pressing the electrically conductive surfaces together with the mesh and adhesive material therebetween with sufficient pressure that the mesh contacts the opposing electrically conductive surfaces; and curing the adhesive material while pressing the electrically conductive surfaces together. In an ultrasonic transducer, electrically conductive mesh can be placed between a metallized rear surface of a piezoelectric ceramic layer and a printed circuit on a dielectric substrate. Alternatively, the mesh can be placed between opposing metallized surfaces of a piezoelectric ceramic layer and an acoustic backing layer, with electrical conductors being passed through the acoustic backing layer for connection to a printed circuit.

Abstract: An insulated mold for thermoplastics, has a recessed mold area and an elevated land area. An insulating material is deposited in the mold area and a hard layer of metal is deposited on the insulating layer. The land protects the insulating layer from delamination. Also, in some embodiments, a transition between the land and the recessed mold area is provided. The protective member may also be employed to hold down the edge of the insulating layer and to shield the edge from molten thermal plastics, thereby preventing delamination.

Abstract: Articles such as molds for thermoplastics, having an insulating layer preferably of resin deposited on the metal core materials, have a second layer of metal suspended in resin deposited on said insulating layer. The second layer may contain metal in platelet form as the inner mold surface, or may contain metal in fiber, whisker or irregular form with a further metal coating deposited thereon to provide resistance to abrasion. In the latter case, the adhesion of the further metal coating to the mold surface is higher than is the case if no metal-containing resin layer is present. A number of injection molding techniques utilizing the mold to produce finished parts in a variety of plastics materials are disclosed.

Abstract: A multilayered insulated mold structure for forming textured articles is disclosed. An insulation layer is deposited on the mold core and a multilayered skin layer is deposited on the insulation layer. The skin is formed of a plurality of sublayers, including a corrosion-resistant phosphorous-rich nickel region on the insulation layer acting as an etchant stop, and an non-corrosion resistant, or etchable, phosphorous-poor nickel region on the corrosion-resistant layer. The upper layer is uniformly textured by selective etching down to a depth terminating at the interface between the layers, but the insulation layer is protected. A method of molding uniformly textured articles is also disclosed, as is a method of making a mold suitable for producing uniformly textured articles and a method for making such a mold surface having bulk imperfections.

Abstract: Articles such as molds for thermoplastics, having an insulating layer preferably of resin deposited on the metal core materials, have a second layer of metal suspended in resin deposited on said insulating layer. The second layer may contain metal in platelet form as the inner mold surface, or may contain metal in fiber, whisker or irregular form with a further metal coating deposited thereon to provide resistance to abrasion. In the latter case, the adhesion of the further metal coating to the mold surface is higher than is the case if no metal-containing resin layer is present.

Abstract: A multilayered insulated mold structure for forming textured articles is disclosed. An insulation layer is deposited on the mold core and a multilayered skin layer is deposited on the insulation layer. The skin is formed of a plurality of sublayers, including a corrosion-resistant phosphorous-rich nickel region on the insulation layer acting as an etchant stop, and an non-corrosion resistant, or etchable, phosphorous-poor nickel region on the corrosion-resistant layer. The upper layer is uniformly textured by selective etching down to a depth terminating at the interface between the layers, but the insulation layer is protected. A method of molding uniformly textured articles is also disclosed, as is a method of making a mold suitable for producing uniformly textured articles and a method for making such a mold surface having bulk imperfections.

Abstract: A modified polyimide composition having improved adhesion characteristic to a metal layer and articles obtained therefrom. A limited quantity of water is added to a halogenated polyamic acid to form a reaction product, which is then sprayed, degreased, oxidized and cured into a layer of the modified polyimide composition. The chemically modified surface is then electrolessly plated with a primary metal layer followed by one or more electrolessly or electrolytically applied secondary metal layers until the metal layer of a desired thickness is attained. The present invention further discloses articles such as an EMI shielded enclosure and an insulated mold surface, having metal layers as an EMI shield and an insulating surface, respectively.

Abstract: Method of producing a polyimide layer having improved adhesion to a metal layer thereon. A halogenated polyamic acid is sprayed, partially cured, degreased and oxidized to form a partially cured polyimide layer, which is then electrolessly plated with a primary metal layer and then final cured into the polyimide layer. Electrolessly or electrolytically applied secondary metal layers are then deposited on the primary layer, until the metal layer of a desired thickness is attained. The present invention further discloses articles such as an EMI shielded enclosure and an insulated mold surface, having metal layers as an EMI shield and an insulating surface, respectively.

Abstract: Method of producing a modified polyimide layer to improve adhesion of a metal layer thereon. A limited quantity of water is added to a halogenated polyamic acid to form a reaction product, which is then sprayed, degreased, oxidized and cured into a modified polyimide layer. The chemically modified surface by the aforementioned method is then electrolessly plated with a primary metal layer followed by one or more electrolessly or electrolytically applied secondary metal layers until the metal layer of a desired thickness is attained. The present invention further discloses articles such as an EMI shielded enclosure and an insulated mold surface, having metal layers as an EMI shield and an insulating surface, respectively.

Abstract: A filter for the lubricating oil and refrigerant within refrigerators, freezers and heat pumps is provided which does not interfere with the cooling cycle. The filter utilizes a housing with an orifice that functions as an outlet and an inlet for the transfer of fluids. The filter withdrawn fluids from a location between the compressor and the condenser when the compressor cycles on and returns the fluids when the compressor cycles off. Preferred embodiments of this invention provide for the release of additives to the fluids from the filter material. Also provided by the invention are vapor compression cycle devices which incorporate such a filter and a method of filtering said fluids.