Abstract: Copper oxide films can be reduced to copper with an atmospheric pressure argon and hydrogen plasma at temperatures between 25 and 300° C. A 50-nm-thick CuO layer on a Cu-coated Si wafer, 200 mm in diameter, can be fully reduced by the plasma in 200 seconds at 200° C. The activation energy for the reaction can be approximately 3.7 kcal/mol. X-ray photoelectron spectroscopy can show the copper oxide reduced to metallic copper.

Abstract: A method and device for modifying a surface of a substrate with a plasma in an inert gas environment, comprises enclosing the substrate in a chamber having surrounding sidewalls and a movable coverplate above the surrounding sidewalls with a gap therebetween, affixing a plasma source to the movable coverplate having a plasma outlet through the coverplate into the chamber, purging the chamber with inert gas sufficient to reduce an oxygen concentration of the chamber to several orders of magnitude less than in air, the inert gas entering through and inlet to the chamber and exiting through an outlet from the chamber, and scanning and activating the plasma source affixed to the cover plate over the substrate, such as to expose the surface of the substrate to a reactive species generated by the plasma delivered through the plasma outlet. An inert gas environment is maintained within the chamber throughout the scanning.

Abstract: An atmospheric pressure plasma apparatus and method are disclosed that operate with a multigas mixture to provide a high concentration of reactive neutral species for cleaning and activating the surfaces of substrates, including those with metal interconnects embedded in the substrate.

Abstract: A method for treating a surface of a material at atmospheric pressure comprises providing an atmospheric pressure argon plasma source capable of delivering a beam comprising a reactive gas from the source outlet, applying radio frequency (RF) power to the atmospheric pressure argon plasma source for generating the reactive gas in the beam from the source outlet, and translating the atmospheric pressure argon plasma source relative to the material at a distance from the source outlet to said surface close enough for the reactive gas from the atmospheric pressure argon plasma source to contact and treat the surface. Importantly, the beam of the reactive gas at the source outlet comprises a power density of at least 100 W/mm.

Abstract: A system comprises a standalone matching network configured to be coupled to a power controller and an atmospheric pressure plasma creation device by way of coaxial cables of arbitrary length. The matching network comprises circuitry to receive electrical power by way of the first coaxial cable, receive a control signal including instructions to tune the impedance by adjusting a magnitude and phase of the electrical power in a way that minimizes impedance in the system; and output the electrical power by way of the second coaxial cable.

Abstract: Atmospheric pressure plasma devices and methods for preparing the surfaces of fasteners, e.g. nutplates, for adhesive bonding are disclosed. A device supports a fastener to dispose a contact surface of the fastener to receive an atmospheric pressure plasma flow, thereby activating the contact surface to be bonded. A spacer is used to properly support the fastener to receive the plasma treatment. A spacer can comprise a plurality of standoffs on a showerhead port comprising a ground electrode of the plasma generator where plasma is formed in a gas flow across the electrodes.

Abstract: Metal oxide films are reduced to metal with an atmospheric pressure argon and hydrogen plasma at temperatures between 25 and 250° C. A 40-nm-thick copper oxide layer on a copper-coated silicon wafer, 300 mm in diameter, can be fully removed by the argon and hydrogen plasma in under two minutes at 150° C. The fast rate of metal oxide reduction to metal demonstrates that this process is well suited for front- and back-end semiconductor manufacturing, such as for example, flux-free flip chip bonding of microbumps.

Abstract: A method for using a handheld plasma tool for controlled application of low temperature atmospheric pressure plasma to material surfaces, e.g. to enhance bonding and or cleaning is disclosed. The handheld plasma tool can include a hand grip, on/off trigger, display, indicator lights, indexing pin, marking device, cable connections for gas supply and electrical power, and a plasma head for generating at least one reactive gas species at a low temperature. The handheld plasma tool can employ a rotatable clamp for treating backside surfaces. The handheld plasma tool can include motorized wheels to scan over a large area at a controlled speed. Other optional nozzles can also be employed for specialized applications.

Abstract: Plasma applications are disclosed that operate with argon and other molecular gases at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species. The plasma apparatus and the enclosure that contains the plasma apparatus and the substrate are substantially free of particles, so that the substrate does not become contaminated with particles during processing. The plasma is developed through capacitive discharge without streamers or micro-arcs. The techniques can be employed to remove organic materials from a substrate, thereby cleaning the substrate; to activate the surfaces of materials, thereby enhancing bonding between the material and a second material; to etch thin films of materials from a substrate; and to deposit thin films and coatings onto a substrate; all of which processes are carried out without contaminating the surface of the substrate with substantial numbers of particles.

Abstract: Plasma applications are disclosed that operate with argon or helium at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species in the effluent stream. Laminar gas flow is developed prior to forming the plasma and at least one of the electrodes can be heated which enables operation at conditions where the argon or helium plasma would otherwise be unstable and either extinguish, or transition into an arc. The techniques can be employed to clean and activate a metal substrate, including removal of oxidation, thereby enhancing the bonding of at least one other material to the metal.

Abstract: Atmospheric pressure plasma devices and methods for preparing the surfaces of fasteners, e.g. nutplates, for adhesive bonding are disclosed. A device supports a fastener to dispose a contact surface of the fastener to receive an atmospheric pressure plasma flow, thereby activating the contact surface to be bonded. A spacer is used to properly support the fastener to receive the plasma treatment. A spacer can comprise beveled edges of a grounded enclosure which electrically connects the contact surface of the fastener to the plasma generator where plasma is formed in a gas flow along the electrodes. Alternately, a spacer can comprise a plurality of standoffs on a showerhead port comprising a ground electrode of the plasma generator where plasma is formed in a gas flow across the electrodes.

Abstract: A handheld plasma tool for controlled application of low temperature atmospheric pressure plasma to material surfaces, e.g. to enhance bonding and or cleaning. The handheld plasma tool can include a hand grip, on/off trigger, display, indicator lights, indexing pin, marking device, cable connections for gas supply and electrical power, and a plasma head for generating at least one reactive gas species at a low temperature. The handheld plasma tool can employ a rotatable clamp for treating backside surfaces. The handheld plasma tool can include motorized wheels to scan over a large area at a controlled speed. Other optional nozzles can also be employed for specialized applications.

Abstract: Plasma applications are disclosed that operate with argon or helium at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species in the effluent stream. Laminar gas flow is developed prior to forming the plasma and at least one of the electrodes can be heated which enables operation at conditions where the argon or helium plasma would otherwise be unstable and either extinguish, or transition into an arc. The techniques can be employed to clean and activate a metal substrate, including removal of oxidation, thereby enhancing the bonding of at least one other material to the metal.

Abstract: Plasma applications are disclosed that operate with argon and other molecular gases at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species. The plasma apparatus and the enclosure that contains the plasma apparatus and the substrate are substantially free of particles, so that the substrate does not become contaminated with particles during processing. The plasma is developed through capacitive discharge without streamers or micro-arcs. The techniques can be employed to remove organic materials from a substrate, thereby cleaning the substrate; to activate the surfaces of materials, thereby enhancing bonding between the material and a second material; to etch thin films of materials from a substrate; and to deposit thin films and coatings onto a substrate; all of which processes are carried out without contaminating the surface of the substrate with substantial numbers of particles.

Abstract: Techniques for producing composites outside of an autoclave that have smooth surface finishes are disclosed. The smooth composite surface, free of porosity, can be fabricated by curing the prepreg in a tool that includes a novel microstructure. In conventional composite manufacturing, some degree of porosity appears to originate from trapped gas bubbles that form during curing. The microstructure can provide a mechanism for the gas bubbles to escape from the tooling, thereby eliminating porosity and yielding a smooth surface finish on the out-of-autoclave composite. The microstructure can be applied to the tool surface using an inkjet process applying an acrylic resin curable with ultraviolet light.

Abstract: Plasma applications are disclosed that operate with helium or argon at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species in the effluent stream. Laminar gas flow is developed prior to forming the plasma and at least one of the electrodes is heated which enables operation at conditions where the helium plasma would otherwise be unstable and either extinguish, or transition into an arc. The techniques can be employed to remove organic materials from a substrate, thereby cleaning the substrate; activate the surfaces of materials thereby enhancing adhesion between the material and an adhesive; kill microorganisms on a surface, thereby sterilizing the substrate; etches thin films of materials from a substrate, and deposit thin films and coatings onto a substrate.

Abstract: An argon and helium plasma apparatus and method are disclosed that operate with argon or helium at atmospheric pressure, and at low temperatures, and with high concentrations of reactive species in the effluent stream. Laminar gas flow is developed prior to forming the plasma and at least one of the electrodes is heated which enables operation at conditions where the argon or helium plasma would otherwise be unstable and either extinguish, or transition into an arc. The apparatus and method can be employed to remove organic materials from a substrate, thereby cleaning the substrate; activate the surfaces of materials thereby enhancing adhesion between the material and an adhesive; kill microorganisms on a surface, thereby sterilizing the substrate; etches thin films of materials from a substrate, and deposit thin films and coatings onto a substrate.

Abstract: Apparatuses and methods for treating wounds are disclosed. An apparatus for treating wounds is disclosed comprising an instrument for generating a low temperature, atmospheric pressure plasma, a means of flowing gas comprising mixing an inert gas and a reactive gas through the instrument, and a means of contacting the wound with the reactive gases flowing out of the instrument. A method for treating wounds using reactive gases is disclosed. The use of atmospheric pressure plasmas for treating wounds is also disclosed.

Abstract: A method for bonding composites together that is fast and effective, and can be applied to any structure regardless of its size and shape, and its related product are disclosed. The method comprises first subjecting at least a part of a composite work piece to a low-temperature, atmospheric pressure plasma, wherein the reactive gas from the plasma is projected out of the device and onto the surface of the composite work piece, then applying an adhesive to the surface of the treated composite work piece, and joining the composite work piece together with a second work piece. The adhesive may be cured such that it forms a strong, permanent bond. The atmospheric plasma delivery device may be translated over the composite surface by hand or with a robot. The plasma device may be self-contained and portable, and can be moved to a location that is convenient for treating the composites.

Abstract: Devices and methods for generating a low-temperature, atmospheric pressure plasma are disclosed. A plasma device may include a first electrode having an inlet for a gas, a second electrode having an outlet for the gas and disposed proximate to the first electrode to form a substantially uniform gap therebetween. The gas flows along the substantially uniform gap and from a plurality of different directions to converge and flow through the outlet. High frequency electrical power is applied between the first electrode and the second electrode to generate a plasma within the gas flow emerging at the outlet. Precursor chemicals are added to the plasma flow at the outlet. Various electrode designs may be implemented and various applications involving surface treatment of materials with the low-temperature atmospheric plasma, including surface activation, cleaning, sterilization, etching and deposition of thin films are disclosed.