Patents by Inventor N. Christian McGrath

N. Christian McGrath has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4310566
    Abstract: A plurality of porous valve-metal pellets, having the conventional oxide dielectric film, solid electrolyte, metallic counterelectrode, and insulative resin protective layer over the counterelectrode, are suspended by their anode risers from processing bars held in a carrier rack. Anode and cathode end-cap terminals are subsequently formed over opposite ends of each pellet, while the pellets are still suspended from the processing bars held in the carrier rack, by the selective steps of dipping and removing and curing of silver-loaded paint, and then nickel immersion plating over the cured silver caps, and then coating the nickel film with solder.
    Type: Grant
    Filed: May 22, 1980
    Date of Patent: January 12, 1982
    Assignee: Sprague Electric Company
    Inventor: N. Christian McGrath
  • Patent number: 4205099
    Abstract: A method is described for making terminal pads, and more particularly solderable bump terminals on a plurality of semiconductor devices formed in a silicon wafer. Two spaced aluminum layers have electrical connection to the P-type region and the N-type region, respectively, of a PN junction of each device. A permanent protective glass layer is deposited over the active face of the wafer, having holes opened over the terminal pads. The wafer is covered with a temporary insulative masking layer except over terminal pad portions of the two aluminum layers, respectively. The wafer is submersed in a zinc plating solution and subsequently in a nickel plating solution to form a nickel bump on the terminal pad portions. A dark environment is provided about the PN junctions to avoid deplating aluminum from some of the aluminum pads due to photo-electric currents in the immersion solution.
    Type: Grant
    Filed: April 14, 1978
    Date of Patent: May 27, 1980
    Assignee: Sprague Electric Company
    Inventors: Leith Jones, N. Christian McGrath
  • Patent number: 4203194
    Abstract: A plurality of porous valve-metal pellets are suspended by their anode riser wires from a holding bar. After the conventional steps of anodically forming an oxide film over the surfaces of the pellets and depositing a solid electrolyte and a metallic counterelectrode over the film, an insulative resin layer is applied over the pellets by an electrostatic fluidized powder-bed coating step, selective air-stream powder-removal steps and heat curing steps. Anode and cathode end cap terminals are subsequently formed over opposite ends of each pellet, preferably by applying and curing a silver loaded paint, curing the paint, nickel immersion plating over the silver and cladding the nickel film with solder.
    Type: Grant
    Filed: July 17, 1978
    Date of Patent: May 20, 1980
    Assignee: Sprague Electric Company
    Inventor: N. Christian McGrath
  • Patent number: 3988518
    Abstract: A long metal lead frame strip is wound onto a reel with a plastic ribbon interleaved therein to separate adjacent turns of the strip on the reel. The reel is subsequently submersed in an immersion plating solution. Metal ions of the plating solution displace metal atoms at the surface of the strip to form a uniformly thick plating thereon, even in areas that are contacted by the spacing ribbon.
    Type: Grant
    Filed: August 15, 1975
    Date of Patent: October 26, 1976
    Assignee: Sprague Electric Company
    Inventor: N. Christian McGrath