March 2009
Dry Film Imaging Considerations for Photochemical Machining
Adhesion is the key to the successful etching
of photochemical machining parts with dry film
photoresist. Specifically, the imaging process must
be optimized to gain sufficient attachment between
the dry film and the metal surface to ensure survival
through the final etching process. Total dry film
adhesion consists of both chemical and mechanical
components. Unfortunately, dry film can only
chemically complex via its acid chelation system with
copper and copper-based alloys. So, we must focus
on mechanical means to get the dry film to adhere to
the most common photochemical machining substrates.
Bill Wilson, DuPont Electronics
