2005 R&D 100 Winner
NanoFoil is a nanoengineered heat source that enables lead-free soldering and brazing of materials at room temperature. Developed by Timothy Weihs and Omar Knio at Reactive NanoTechnologies (RNT) in Hunt Valley, Md., with support from researchers at Lawrence Livermore National Laboratory, Calif., and Johns Hopkins Univ., Baltimore, Md., the NanoFoils are manufactured by vapor depositing hundreds of nanoscale layers that alternate between elements, such as aluminum and nickel. By thermally pulsing one end of the resulting foil with energy, the nanoscale layers begin to mix and release heat to the surrounding foil. This leads to more chemical mixing in adjoining areas of the foil and a chemical reaction that self-propagates across the full length of the foil.
NanoFoil can be used to join a broad range of components consisting of metals, ceramics, semiconductors, and polymers. Bonding can be performed in many environments and is completed in a second or less. Because the heat is localized, components can generally be bonded without thermal damage. There also are basically no capital costs involved in the process and it is easily automated. The wide range of NanoFoil applications include the hermetic sealing of microelectronic devices, mounting of sputter targets, ignition of solid propellants, and defensive security flares.
Nanoengineered heat source