| abstract |
Process and structure for etching copper, as in the manufacture of printed circuit boards. The copper is exposed to a gaseous or liquid oxidant in the presence of a catalyst which promotes the reaction of copper with the oxidant. In some embodiments, the catalyst is carried by a medium which also serves as a receiver for oxidized copper species produced by the reaction, and in one preferred embodiment, the medium comprises a laminated structure having a first layer which contains a catalyst and a second layer which receives the oxidized copper species. The etching is substantially anisotropic, which alleviates the problem of undercutting. |