Fine Lines in High Yield (Part CXLII): Improving and Measuring Tenting Performance of Dry Film Photoresists

摘要

A few years back, I covered dryrn film tenting in three Tech Talk columns. The tenting process as an alternative to pat-itern plating had been championed by IBM circuit board facilities and alumni of these sites that spread the technology to other sites. With the demise of the IBM shops, the tenting process has lost visibility in the U.S. and Europe but is alive and well in Japan. The tenting process has also been employed in applications other than the classic alternative to pattern plating. To avoid double drilling, the pattern plate resist can be used to tent tooling holes of the board that is being pattern plated.