Amp LLC

Wake Forest University

The Whitaker Corporation

Richard T Williams

Jeff C Wu

George B Cvijanovich

John R Rowlette

Richard Henry Zimmerman

David B Wrisley, Jr

Charles P Brooks

Marlin R McCleaf

Eben Daniel Thoma

William E Pendleton

Charles W Himes

Scintillators of various constructions and methods of making and using the same are provided. In some embodiments, a scintillator comprises at least one radiation absorption region and at least one spatially discrete radiative exciton recombination region.

Scintillators and applications thereof

The present invention is directed to a method for producing a smooth and continuous pressure bonded layer of a material on a base substrate through the driving force of a pulsed laser. The method comprises the steps of selecting a laser absorptive material. Then applying thereto a thin layer of the material for pressure bonding to the base substrate. Next, placing the base substrate and the thin layer of material on the laser absorptive material in a vacuum, then placing the base substrate in close proximity to the thin layer of material. Finally, directing pulsed laser energy toward the laser absorptive material and the layer to be pressure bonded, whereby the laser energy is absorbed by the laser absorptive material causing heating and vaporization thereof to a controlled depth of the laser absorptive material, leaving remaining portions of the laser absorptive material unvaporized after the vaporization to act as a support for the material to be bonded. After bonding, the thin material adheres to the base substrate when the remaining continuous absorptive material is peeled away, the vaporization having provided the necessary pressure for pressure bonding on to the base material.

Laser transfer deposition

Invention is directed to a method of metallurgically bonding a layer of a first material, such as gold, to the surface of a second material, such as copper, by the use of the driving force of the energy from a pulsed laser. The method comprises the steps of selecting a thin polymeric film, where said polymer is characterized by a high optical coefficient of absorption at the wavelength of said laser, and applying to said polymeric film a thin layer of said first material for bonding to the second material. The second material is placed in close proximity to the thin layer of the first material. Intermediate the laser and the target a rotating optical scanner is provided to intercept the beam of the laser prior to directing the focused beam thereof toward the polymeric film. The repetition rate of the laser is synchronized with the rotating optical scanner to cause the focused beam of the laser to move across said polymeric film at a velocity less than the velocity of sound through the material. As a result thereof, the polymeric film is explosively evaporated causing a build up of pressure driving the first material toward the second material, whereby a moving contact zone is developed therebetween to drive surface contaminants and oxides from the second material.

Method of bonding by laser driven explosive cladding

This invention is directed to a method for producing a smooth and continuous pressure bonded layer of a material such as gold or other precious metal, to a substrate, such as a metal substrate, through the driving force of a pulsed laser. The method comprises the steps of selecting a laser transparent substrate, applying thereto a thin polymeric film, where said polymer is characterized by a high optical coefficient of absorption to the wavelength of said laser. Preferably, such coefficient is at least 2.times.10.sup.4 cm.sup.-1. To the polymeric film, a thin layer or film of the material, such as gold is applied. Thereafter, the laser transparent substrate, containing the dual layers is placed in close proximity to the substrate or workpiece upon which such material is to be deposited. To this assembly, a pulsed laser is directed through the transparent substrate toward the polymeric film and material layer, whereby the laser energy is absorbed by the polymeric causing heating and vaporization thereof over a controlled depth of such polymer film. The vaporization provides the necessary pressure to blow-off the remaining polymer film and propel the material layer onto the substrate or workpiece. The resulting pressure bonded layer, i.e. gold or other precious metal, is smooth and continuous.

The present invention is directed to a beam allocation and delivery system for an excimer laser in which substantially the full energy from such laser is delivered to a precise area or areas of a workpiece. This efficient system is achieved by the use of one or more elongated light-guides to direct the laser beam. Included therewith are means to shape and focus said beam to a reduced image on the workpiece. Preferably, the shaping and focussing is achieved by changing the cross-section of the light-guide from a first configuration to a second configuration, and by an imaging lens.

Beam allocation and delivery system for excimer laser

A method of cleaning a metal surface by means of a laser to improve the surface characteristics, prior to plating thereover with a noble metal, such as gold. More particularly, the method hereof includes the steps of illuminating the desired areas of said metal surface with a laser beam; provided, however, the laser power density is controlled to vaporize surface contaminants and embedded foreign materials, without significantly altering the properties of the metal, in preparation for plating said cleaned areas with said noble metal.

Laser cleaning of metal stock

A method for the selective plating of a metal substrate on which a thin polymeric plating resist is first applied, followed by the selective removal of said resist to expose portions of said substrate to plating, and plating. More particularly, the method hereof includes the steps of selecting a laser wavelength which couples well to the metal substrate, choosing a polymer based plating resist having a low optical coefficient of absorption at said wavelength, curing said resist, subjecting selective areas of said resist to a single excimer laser shot, having a short wavelength, to cause ablative removal of the resist over the selective areas of said substrate, and subjecting said exposed portions of said substrate to metal plating.

Selective plating by laser ablation

A method and apparatus for improving the integrity of metal plated composites is disclosed. Plating improvements are achieved by first irradiating a nickel plated substrate, prior to application of a noble metal plating layer, to smooth any surface discontinuities or irregularities. Excimer laser pulses, having a duration of less than 100 nanoseconds, are employed to partially liquefy the upper surface of the nickel plating on the substrate. This invention is compatible with conventional plating processes, such as electroplating.

Growing community of inventors

Winston-Salem, NC, United States of America

Richard T Williams