A method for applying a metallization on an insulator and for the opening of the through holes in the latter by means of the same mask

摘要

A process is disclosed for applying a metallisation layer on an insulator and for piercing through-holes in the insulator with one and the same mask. A substrate (1) has a first (3) and a second (4) insulating layer on its surface (2), a covering layer (5) on the second insulating layer (4), a structured masking layer (6) on the covering layer (5) and metal-filled through-holes (7) that extend from the rear side of the substrate to its surface (2). The masking layer (6) is structured in such a way that it has openings in the areas located above the through-holes (7) and in the areas to be provided with a metallic layer (7). The covering layer (5) is pierced in the areas that are not covered by the structured masking layer (6) by a first etching process. The second insulating layer (4) is then laser ablated in the areas located above the metal-filled through-holes (7) by means of a dielectric mask. The first insulating layer (3) in the areas located above the metal-filled through-holes (7) and the second insulating layer (4) in the areas to be provided with a metallic layer (8) are then pierced at the same time by a second etching process. The through-holes (7) are thus completely freed from the first insulating layer (3), the second insulating layer (4) is completely removed from the areas to be provided with a metallic layer (8) and the first insulating layer (3) remains substantially intact on the surface (2) of the substrate.