Anisotropic etching for silicon micromachining

Silicon micromachining is the collective name for several processes by which three dimensional structures may be constructed from or on silicon wafers. One of these processes is anisotropic etching, which utilizes etchants such as KOH and ethylene diamine pyrocatechol (EDP) to fabricate structures from the wafer bulk. This project is a study of the use of KOH to anisotropically etch (lOO)-oriented silicon wafers. The thesis provides a thorough review of the theory and principles of anisotropic etching as applied to (100) wafers, followed by a few examples which serve to illustrate the theory. Next, the thesis describes the development and experimental verification of a standardized procedure by which anisotropic etching may be reliably performed in a typical research laboratory environment. After the development of this procedure, several more etching experiments were performed to compare the effects of various modifications of the etching process. Multi-step etching processes were demonstrated, as well as simultaneous doublesided etching using two different masks. The advantages and limitations of both methods are addressed in this thesis. A comparison of experiments performed at different etchant temperatures indicates that high temperatures (800 C) produces reasonably good results at a very high etch rate, while lower temperatures (500 C) are more suited to high-precision structures since they produce smoother, higher-quality surfaces.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Electrical Engineering

Department dc:contributor.department

Electrical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1994

Author dc:creator

• Hobbs, Neil Townsend

Chairs dc:contributor.committeechair

• Moore, Daniel J.
• Elshabini-Riad, Aicha A.

Committee member dc:contributor.committeemember

• Desu, Seshu B.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-01172009-063106

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/40632