Conductive connection of the laser signal conductor tracks, which is introduced with pastes, metallized pads on aln substrates

摘要

The present invention relates to a process for the deposition of metallic coatings on ceramic substrates (1), wherein the metallic coatings comprise pads (2) and signal conductor tracks (3) and the pads (2) a greater thickness than the signal conductor tracks (3), and in at least one process step with the metallizations are applied by screen printing process is known per seThus economical pads (2) with a large thickness and signal conductor tracks (3) with a small thickness on a ceramic substrate (1) can be applied, the following process steps are proposed to be carried out in series:a. the use of a ceramic substrate (1) made of aluminum nitride (aln),example, printing of the pads (2) with the screen printing process using a screen with one or more printing operations,c. introduction of the signal conductor tracks (3) with a laser, wherein the laser beam along the signal conductor tracks (3) to be created on the ceramic substrate (1) is deflected and extends through the heat of the laser beam at the location of incidence of the laser beam on the substrate (1) the aluminum nitride of the substrate (1) which converts into the electrically conductive aluminum,that at the same time as or after the process step c steering of the laser beam on the connecting region (4) between the pads (2) and the signal conductor tracks (3) for the creation of an electrically conductive connecting region (4), which the signal conductor tracks (3) with the pads (4) and electrically conductively connectse, optionally, a galvanic application of a metal coating on the pads (2) and the signal conductor tracks (3).