Low-power, low-pressure reactive-ion etching process for silicon etching with vertical and smooth walls for mechanobiology application

作者：Ashraf Mohammed; Sundararajan Sree V; Grenci Gianluca^*

来源：Journal of Micro/ Nanolithography, Mems, and Moems, 2017, 16(3): 034501.

DOI：10.1117/1.JMM.16.3.034501

• reactive-ion etching
• silicon etching
• pattern transfer

We report our findings in developing a low-power etching recipe using a newly acquired reactive-ion etching (RIE) tool (RIE-10NR, Samco, Japan), with the aim of achieving smooth and vertical sidewalls in micro-patterned silicon substrate. We used a combination of CF4, SF6, and O-2 gases, which at low power (30 W) and low pressure (2 Pa) allowed for vertical silicon etching (aspect ratio similar to 2). We used photoresist and silicon oxide as the etching masks. As it is a continuous etching process, scalloping effects were not present, which is contrary to the process done with an inductively coupled plasma-based "Bosch" approach. We also show a successful use of these microstructures as master mold in soft-lithographic techniques for producing devices in elastomeric materials that have applications in mechanobiology. To the best of our knowledge, the recipe we present here has the lowest combination of power and pressure for etching silicon with vertical profile using a standard, parallel plates RIE tool. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

• 出版日期2017-7