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:
Dec. 11, 2007
Filed:
Jun. 30, 2004
Usha Raghuram, San Jose, CA (US);
Michael W. Konevecki, San Jose, CA (US);
Samuel V. Dunton, San Jose, CA (US);
Usha Raghuram, San Jose, CA (US);
Michael W. Konevecki, San Jose, CA (US);
Samuel V. Dunton, San Jose, CA (US);
Sandisk 3D LLC, Sunnyvale, CA (US);
Abstract
A method for etching to form a planarized surface is disclosed. Spaced-apart features are formed of a first material, the first material either conductive or insulating. A second material is deposited over and between the first material. The second material is either insulating or conductive, opposite the conductivity of the first material. The second material is preferably self-planarizing during deposition. An unpatterned etch is performed to etch the second material and expose the top of the buried features of the first material. The etch is preferably a two-stage etch: The first stage is selective to the second material. When the second material is exposed, the etch chemistry is changed such that the etch is nonselective, etching the first material and the second material at substantially the same rate until the buried features are exposed across the wafer, producing a substantially planar surface.