Silicon micromachining in 25 wt% TMAH without and with surfactant concentrations ranging from ppb to ppm

Akarapu, A and Pal, P (2017) Silicon micromachining in 25 wt% TMAH without and with surfactant concentrations ranging from ppb to ppm. Microsystem Technologies, 23 (1). pp. 47-54. ISSN 0946-7076

[img] Text (Author version post-print)
2004.pdf - Accepted Version
Restricted to Registered users only

Download (1MB) | Request a copy

Abstract

Tetramethylammonium hydroxide (TMAH) is one of the most commonly used anisotropic etchants in silicon wet bulk micromachining. It has outstanding etching characteristics such as compatibility with semiconductor processes and provides high etch selectivity between silicon and silicon dioxide. In this work, we have investigated the effect of surfactant concentration ranging from 20 ppb to 1000 ppm on the etching characteristics of 25 wt% TMAH for bulk micromachining of Si{100} and Si{110}. Triton X-100 with formula C14H22O(C2H4O)n, where n = 9–10, is used as surfactant. The major objective of this work is to determine the surfactant concentration at which the etch rate, etched surface morphology and convex corner undercutting are significantly affected. Undercutting length and etched depth are measured using 3D scanning optical microscope. Surface morphology of etched silicon samples are inspected using scanning electron microscope. The surfactant concentration below 100 ppb does not affect etching characteristics significantly, while the effect of surfactant concentration above 100 ppb is substantial on the undercutting at convex corners on Si{100} surface, etch rate and etched surface roughness of Si{110}. The etch rate and etched surface morphology of Si{100} are not influenced considerably when the surfactant is added into 25 wt% TMAH.

[error in script]
IITH Creators:
IITH CreatorsORCiD
Pal, PUNSPECIFIED
Item Type: Article
Uncontrolled Keywords: ALKALINE-SOLUTIONS; SIO2 MICROCANTILEVER; TRITON SURFACTANT; KOH; BEHAVIOR; FABRICATION; ADDITIVES; ALCOHOL
Subjects: Others > Nanotechnology
Physics > Astronomy Astrophysics
Divisions: Department of Physics
Depositing User: Team Library
Date Deposited: 02 Nov 2015 08:19
Last Modified: 14 Aug 2017 06:36
URI: http://raiith.iith.ac.in/id/eprint/2004
Publisher URL: https://doi.org/10.1007/s00542-015-2699-9
OA policy: http://www.sherpa.ac.uk/romeo/issn/0946-7076/
Related URLs:

Actions (login required)

View Item View Item
Statistics for RAIITH ePrint 2004 Statistics for this ePrint Item