Advanced photoresist technologies for microsystems

A growing interest in the development of high aspect ratio photoresists for micromachining microsystems (MST) products has resulted in the availability of a number of commercially available photoresist products. This paper describes in detail the applications of three such resists, namely EPON SU-8, Clariant AZ 4562 and the Shipley electroplated photoresist ED2100. Applications such as etch hard masks, micromoulds, severe topography coatings for metal interconnects and photoplastic mouldings are discussed, and novel examples are presented of where these resists are currently used in both telecom and microfluidic markets. In particular, the versatility of the photoplastic negative resist EPON SU-8, which is used in a number of MST prototypes, is demonstrated. Future trends in resist technologies for MST are discussed.