Original title:
Wet Etching Of Sio2 As Sacrificial Layer With Infinite Selectivity To Al
Authors:
Brodský, Jan Document type: Papers
Language:
cze Publisher:
Vysoké učení technické v Brně, Fakulta elektrotechniky a komunikačních technologií Abstract:
This work presents an unusual method for releasing microelectromechanical systems which contain an Al layer. This is done by wet etching of SiO2 as a sacrificial layer. Mixture of 49% HF acid and 20% H2SO4∙SO3 (oleum) is used. Oleum keeps the solution water-free and subsequently prevents the attack of Al layer. Exceptional etch rate (≈ 1 μm·min−1) of thermally grown SiO2 is achieved by this method. The infinite selectivity to Al layer is verified by measuring the thickness of layer before and after etching. The etching itself is done in an ordinary fume hood in polytetrafluorethylene (PTFE) beaker.
Keywords:
MEMS; sacrificial layer; selectivity; SiO2 etching Host item entry: Proceedings I of the 26st Conference STUDENT EEICT 2020: General papers, ISBN 978-80-214-5867-3
Institution: Brno University of Technology
(web)
Document availability information: Fulltext is available in the Brno University of Technology Digital Library. Original record: http://hdl.handle.net/11012/200582