Plasma Desmearing of Multilayer Boards

The paper briefly reviews the problems associated with resin smear in the manufacture of multilayer boards, the various types of material involved, and their influence on smear, and some of the techniques available for assessing the degree of smear. Following a short discussion on current methods of removing smear, the paper goes on to provide a critical comparison of traditional ‘wet’ chemical processes with the newer ‘dry’ plasma techniques. Key advantages of plasma desmearing are highlighted and the paper concludes with a more detailed description of the I V Products approach and current systems, together with results of recent development work.