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:
Nov. 27, 1984
Filed:
Sep. 23, 1983
Applicant:
Inventor:
Thomas Keyser, Mountain View, CA (US);
Assignee:
Fairchild Camera & Instrument Corp., Mountain View, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B44C / ; C03C / ; C03C / ; C23F / ;
U.S. Cl.
CPC ...
156643 ; 156651 ; 156653 ; 156657 ; 1566591 ; 1566611 ; 2041 / ;
Abstract
The disclosure relates to techniques for etching layered materials to produce features with beveled edges, for example, wells in silicon oxide layers employed in integrated circuit fabrication. An anisotropic etch may be employed to form wells with vertical walls in the silicon oxide layer, and an isotropic etch may be employed to bevel peripheral corners of the walls. In preferred embodiments, a double mask of a photoresist layer on an underlying thin film may be used to define the limits of the anisotropic and isotropic etches, respectively.