Method of photolithographically metallizing at least the inside of holes arranged in accordance with a pattern in a plate of an electrically insulating material

A method of photolithographically metallizing at least the walls of holes arranged in accordance with a pattern in a plate of an electrically insulating material, said method comprising:

• (a) providing a chromium layer on at least one surface of the plate and on the walls of the holes,
• (b) providing an aluminum layer on said chromium layer,
• (c) providing a metal layer of a metal selected from the group consisting of chromium, cobalt, nickel, zirconium and titanium and alloys of at least two of said metals on said aluminum layer,
• (d) electrophoretically providing a photosensitive, negative electrophoretic lacquer coating on said metal layer,
• (e) exposing said lacquer coating to radiation in accordance to a pattern to form exposed and unexposed portions of said lacquer coating, said exposed portions being formed at least in the holes,
• (f) developing said lacquer coating so as to remove said unexposed portions of said lacquer coating and uncover portions of said metal layer present underneath said unexposed portions of said lacquer coating,
• (g) removing, by etching, said uncovered portions of said metal layer and underlying portions of said aluminum and chromium layers while preserving said exposed portions of said lacquer coating and portions of said chromium, aluminum and metal layers underlying said exposed portions of said lacquer coating and
• (h) stripping said exposed portions of said lacquer coating from portions of said metal layer underlying said exposed portions of said lacquer coating.