“Etching under the corner” - inclined macropores by reactive ion etching

✍ Scribed by Grigoras, Kestutis ;Franssila, Sami

• Book ID: 105365238
• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 418 KB
• Volume: 206
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200881066

✦ Synopsis

Abstract

Deep reactive ion etching at cryogenic temperatures has been used for a macropore formation in silicon. A double‐mask set‐up was applied. The first mask of a patterned thin aluminum or silicon oxide layer determined the pore size and density, and thicker patterns of silicon, glass, or SU‐8 acted as a secondary mask changing the angle of the etched pores. Up to 45° inclined macropores have been obtained at the edges of a secondary mask. The inclination dependencies on the shape and structure of the secondary mask and on the etching parameters have been investigated. The effect is explained by the non‐uniformity of etching ion direction at the sidewall of a thick secondary mask. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)