The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 20, 1994
Filed:
Dec. 23, 1991
Applicant:
Inventor:
Steve D Braymen, Ames, IA (US);
Assignee:
Iowa State University Research Foundation, Inc., Ames, IA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
156644 ; 156656 ; 156657 ; 156662 ; 252 791 ; 437225 ; 437228 ;
Abstract
A process for selectively etching silicon comprises preparing a solution of etchant which is a non-selective etch for at least silicon and aluminum. The prepared solution is preconditioned by adding atomic silicon to the solution and aging the solution after the addition of silicon for at least 30 minutes. Then, silicon substrates carrying aluminum are immersed in the preconditioned solution to etch the silicon while leaving the aluminum substantially unaffected.