Soldering terminology

Depending on the active requirement, the inner layers of multilayer PCBs should have either a glossy or a matte finish. Both of these surface structures have their own special characteristics. The former has (1) good wettability , (2) corrosion resistance, (3) and low heat discoloration, whereas the latter (1) reacts well with synthetic resins and (2) has good peel resistance. The chemical treatment of the copper is adapted to the respective requirements in advance. The brown oxide treatment is one of the methods for refining shiny copper surfaces and increases the adherence to resin. Its name refers to the brown color it gives to copper. The oxidizing agents used for this purpose are listed in the table below. See also Haloing and Black oxide treatment.