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Title: Selective etchant for oxide sacrificial material in semiconductor device fabrication

Abstract

An etching composition and method is disclosed for removing an oxide sacrificial material during manufacture of semiconductor devices including micromechanical, microelectromechanical or microfluidic devices. The etching composition and method are based on the combination of hydrofluoric acid (HF) and sulfuric acid (H.sub.2 SO.sub.4). These acids can be used in the ratio of 1:3 to 3:1 HF:H.sub.2 SO.sub.4 to remove all or part of the oxide sacrificial material while providing a high etch selectivity for non-oxide materials including polysilicon, silicon nitride and metals comprising aluminum. Both the HF and H.sub.2 SO.sub.4 can be provided as "semiconductor grade" acids in concentrations of generally 40-50% by weight HF, and at least 90% by weight H.sub.2 SO.sub.4.

Inventors:
;
Issue Date:
Research Org.:
Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1175355
Patent Number(s):
6893578
Application Number:
10/010,850
Assignee:
Sandia Corporation
Patent Classifications (CPCs):
C - CHEMISTRY C03 - GLASS C03C - CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUS ENAMELS
B - PERFORMING OPERATIONS B81 - MICROSTRUCTURAL TECHNOLOGY B81C - PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
DOE Contract Number:  
AC04-94AL85000
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Clews, Peggy J., and Mani, Seethambal S. Selective etchant for oxide sacrificial material in semiconductor device fabrication. United States: N. p., 2005. Web.
Clews, Peggy J., & Mani, Seethambal S. Selective etchant for oxide sacrificial material in semiconductor device fabrication. United States.
Clews, Peggy J., and Mani, Seethambal S. Tue . "Selective etchant for oxide sacrificial material in semiconductor device fabrication". United States. https://www.osti.gov/servlets/purl/1175355.
@article{osti_1175355,
title = {Selective etchant for oxide sacrificial material in semiconductor device fabrication},
author = {Clews, Peggy J. and Mani, Seethambal S.},
abstractNote = {An etching composition and method is disclosed for removing an oxide sacrificial material during manufacture of semiconductor devices including micromechanical, microelectromechanical or microfluidic devices. The etching composition and method are based on the combination of hydrofluoric acid (HF) and sulfuric acid (H.sub.2 SO.sub.4). These acids can be used in the ratio of 1:3 to 3:1 HF:H.sub.2 SO.sub.4 to remove all or part of the oxide sacrificial material while providing a high etch selectivity for non-oxide materials including polysilicon, silicon nitride and metals comprising aluminum. Both the HF and H.sub.2 SO.sub.4 can be provided as "semiconductor grade" acids in concentrations of generally 40-50% by weight HF, and at least 90% by weight H.sub.2 SO.sub.4.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2005},
month = {5}
}

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Works referenced in this record:

Sacrificial oxide etching compatible with aluminum metallization
conference, January 1997


Problems of sacrificial etching in the presence of aluminium interconnect
journal, July 1997


Silicon dioxide sacrificial layer etching in surface micromachining
journal, March 1997