Reaktive Nanometer‐Multischichten als maßgeschneiderte Wärmequellen beim Fügen

Reactive nanometer multilayers as tailored heat sources for joining The use of traditional joining techniques like soldering or brazing for heat sensitive microstructures often results in damaging or stress induced deformation of the components. Therefore a technology would be desirable, where heat is produced locally and only for a short time. A very promising approach is the application of socalled reactive nanometer multilayers. Reactive nanometer multilayers consist of several hundreds or a few thousands of alternating layers wi^th thicknesses in the nanometer range that can exothermic react wi^th each other. After a local activation of the chemical reaction by an electrical spark or a laser pulse, a self‐sustaining reaction starts, which propagates parallel to the multilayer surface resulting in a stable intermetallic single layer. The peak temperature of the reaction can be above 1000 8C, but the maximum temperature is only reached for several ten milliseconds. Therefore, the heat remains localized in the vicinity of the solder layers surrounding the reactive multilayer. During the entire process the components to be joined exhibit temperatures close to room temperature. We will show new results concerning the fabrication of reactive nanometer multilayers by magnetron and ion beam sputter deposition and the fabrication of free standing nanometer multilayers.