| abstract |
The present invention relates to a process for the selective metallization of three-dimensional (3D) structures, in particular a redistribution layer, for later electrical connection to a carrier element, such as a printed circuit board. For selective gold-plating of 3D contact structures on the wafer, such as contact bumps electrically connected to bond pads on the wafer through a three-dimensional mechanically flexible structure in the form of It's about the process. This process greatly simplifies the process sequence. According to the invention, the metallization of the pre-prepared three-dimensional structure 1 on the wafer 2 is electrochemically current controlled or potential controlled by partially immersing the structure 1 inside an electrolyte 12 having a fixed surface. Is carried out under. The electrolyte 12 may be a gel electrolyte or the electrolyte 12 may be coated with a membrane through which its corresponding ions can penetrate (see FIG. 2). |