HIGH-ASPECT-RATIO MICROMACHINING VIA DEEP X-RAY-LITHOGRAPHY

High-aspect-ratio microsystems technology (HARMST) can be implemented by using thick photoresist technology, which requires X-ray photons fo r exposure. This was first realized in Germany via the so-called LIGA process. To make this process cost effective, exposures with high-ener gy photons were introduced in 1993 via a University of Wisconsin-Brook haven National Laboratory cooperation. The addition of a solvent bonde d resist technology and replanarization after electroplating and X-ray mask aligning yield a HARMST processing sequence that uses large-area , sequential X-ray masks without diaphragms. This technology may be ap plied to precision engineered parts which do not involve electronics. The processing sequence is also used for high performance linear and r otational, magnetic and electrostatic actuators. System applications i n optics involve spectrometers and other devices. A discussion of US a nd world wide efforts in HARMST points at increasing demands for this type of processing tool.