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:
Jan. 11, 1994
Filed:
Dec. 09, 1991
Applicant:
Inventor:
James F O'Neill, Penfield, NY (US);
Assignee:
Xerox Corporation, Stamford, CT (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
156647 ; 156651 ; 1566541 ; 1566611 ; 156662 ;
Abstract
Three dimensional silicon structures are fabricated from (100) silicon wafers by a single side, two-step anisotropic etching process using different etchants. The two etch masks are formed one on top of the other on a single side of the wafer prior to the initiation of the two-step etching process, with the mask for the largest and deepest etched recesses formed last and used first. The last formed mask is removed to expose the first formed mask. The anisotropic etchant for the smaller, closer toleranced recesses is chosen to minimize mask etching and improve dimensional control of etched recesses requiring close tolerances and uniform sizes.