Channel plating

A system for applying thick coatings of photoresist to thin copper clad laminate for manufacturing printed wiring boards was developed. Using this system, circuits were made with narrow conductors and spacing. Although plating within the channels defined by the resist was successful, circuit fabrication was precluded because of defective laminate materials. Laminate materials clad with copper 0.005 and 0.009 mm thick were found to have a high incidence of foreign metallic inclusions.