Winter 1998
Aqueous Resist Development Considerations for Fine Feature Resist Image Formation
Introduction
Dry film aqueous processable photoresists are used to
define etched features in a variety of metals in the Photochemical
Machining industry. Various applications
place different demands on the image quality of the photoresist
and not all us rs need optimum performance of
the resist. Decorative applications may not have need for
etching very narrow eatures and the edge quality and
exact image size may not be of great concern. Others
may not have a need to create very small features but
they may be required to meet very tight image tolerances.
Whatever the need,resist image quality will be influenced
by the development process. Good resist image
quality is characterized by correct image size as defined
by the phototool, str ght resist sidewalls and a uniform
resist foot that is not negative or overly positive. Good resist
image definition is needed to achieve the best etched
feature quality
David R. McGregor, DuPont Photopolymer and Electronic Materials