UV curable jet-inks for etch resist applications

摘要

Ink-jet printing of electronic devices such as photo-voltaics and circuit boards is attractive for a variety of reasons. This includes simplification of the manufacturing process, customization of design and the production of higher resolution prints. Additionally, the non-contact nature of ink-jet printing allows a wide range of media to be used, such as flexible plastics and silicon wafers.rnThis paper focuses on one class of fluid used in the circuit fabrication process, etch resistant inks. Here, the inks act as temporary masks where they must resist acid but remove readily in alkali, as well as offering mechanical robustness. However, it is difficult for most classes of jet-inks to satisfy these demands, whilst offering reliable jetting, fast dry times and appropriate droplet spread.rnHere we show that UV curable formulations can be developed which offer these desirable properties. A discussion is given on how variations of the backbone chemistry, in terms of functionality and cure response, can have a dramatic effect in these properties. By incorporating a surface pre-treatment, we show that it is possible to fine tune the ink spread to give desirable print quality.