Anisotropic etching rates of single-crystal silicon for TMAH water solution as a function of crystallographic orientation

Author

Sato, K. ; Shikida, M. ; Yamashiro, T. ; Asaumi, K. ; Iriye, Y. ; Yamamoto, M.

Author_Institution

Nayoya Univ., Japan

fYear

1998

fDate

25-29 Jan 1998

Firstpage

556

Lastpage

561

Abstract

We evaluated orientation dependence in the etching rate of single-crystal silicon for tetramethylammonium-hydroxide (TMAH) water solutions. Etching rates for a number of crystallographic orientations were measured for a wide range of etching conditions, including TMAH concentrations of 10 to 25% and temperatures of 70 to 90°C. We found significantly different characteristics from those for KOH water solutions. Firstly, different types of orientation dependence in etching rate were found around (111) between TMAH and KOH. This means the bonding energy of the silicon crystal lattice is not a single factor that dominates orientation dependence, and there exist different etching mechanisms for the two etchants. Secondly, effects of the circulation of etchants on the etching rates were not negligible in TMAH in contrast to KOH system

Keywords

crystal morphology; crystal orientation; elemental semiconductors; etching; organic compounds; silicon; (111); 70 to 90 C; H₂O; KOH water solutions; Si; Si crystal lattice; TMAH water solution; anisotropic etching rates; bonding energy; crystallographic orientation; etching conditions; etching mechanisms; etching rates; orientation dependence; tetramethylammonium-hydroxide water solution; Anisotropic magnetoresistance; Crystallography; Etching; Government; Microstructure; Rough surfaces; Silicon; Surface roughness; Temperature distribution; Water;

fLanguage

English

Publisher

ieee

Conference_Titel

Micro Electro Mechanical Systems, 1998. MEMS 98. Proceedings., The Eleventh Annual International Workshop on

Conference_Location

Heidelberg

ISSN

1084-6999

Print_ISBN

0-7803-4412-X

Type

conf

DOI

10.1109/MEMSYS.1998.659818

Filename

659818