Abstract
This paper presents a new technique of micromachining using single step electrochemical etching in hydrofluoric acid(HF). Using this etching technique, free standing beams with height, width and length of 40μm, 2μm and 250μm, respectively, are made of single crystal silicon. Basic concept of this etching technique is a combination of anisotropic and isotropic etching mode. First, trenches are made at a certain current density. After the desired depth is obtained, the current density is increased to enlarge the trench width without effecting the width of existing trenches. Finally, the trenches are connected under the beams. Thus free standing beams are obtained. After connection of the trenches, electropolishing occurs under the beams, so smooth silicon surface and desired gap length are also obtained.
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© 1998 Springer Science+Business Media Dordrecht
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Ohji, H., Trimp, P.J., French, P.J. (1998). Free Standing Beams Made by Single Step Electrochemical Etching in Hydrofluoric Acid. In: van den Berg, A., Bergveld, P. (eds) Sensor Technology in the Netherlands: State of the Art. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5010-1_32
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DOI: https://doi.org/10.1007/978-94-011-5010-1_32
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