High aspect ratio micromachining by synchrotron radiation direct photo-etching

摘要

We have carried out micromachining of Teflonpolymers such as PTFE, PFA and FEP as well asoptical crystal such as NaCl and LiF by synchrotron radiation direct (without any chemicals)photo-etching and succeeded in creating microstructures with very high aspect ratios. The maximumaspect-ratio achieved was 50 and the maximum processing depth was 1500 microns. Dependence ofthe etching rate on the synchrotron beam current and on the substrate temperature was studied.Based on the study, we could use only x-rays from the synchrotron radiation so as to apply x-raylithography technology (such as using an x-ray mask and processing in He atmosphere) to ourprocess. A rise in the sample temperature results in significant enhancement of the etching rate. Theetching rate measured was on the order of a few 100μm/min. So that this process is much fasterthan hard x-ray deep lithography for the processing of more than 100μm deep microstructures.