Wet Anisotropic Etching Characteristics of Si{100} in TMAH+Triton at near the Boiling Point

Abstract:

The anisotropic silicon etching characteristics of TMAH(tetramethyl ammonium hydroxide)+Triton at near the boiling point were investigated. The etch rate of Si {100}, the convex corners, and the roughness of the etched surface contact with the fabrication of bulk microstructures and thus micromechanical devices in silicon. This study presents that the etch rate of Si {100} in 25 wt.% TMAH with 0.1% Triton at near boiling point (112°C) is 1.37μm/min, it is three times higher than it at 80°C. The surface roughness and convex corners of Si {100} after etching at different temperature were investigated by optical microscope, scanning electron microscope (SEM) and atomic force microscope (AFM). The etching rate and smoothness of an etched surface can be improved simultaneously at near boiling point, meanwhile, the undercutting on convex corner should be accepted.

• Periodical: Key Engineering Materials (Volumes 645-646)
• Pages: 58-63
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.645-646.58
• Online since: May 2015
• Authors: Ming Qiu Yao*, Bin Tang, Wei Su, Gang Tan
• Keywords: Convex Corner, Etching Rate, Near Boiling Point, Silicon, Surface Morphology, TMAH, Triton X-100

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