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:
May. 04, 2004
Filed:
Oct. 14, 1999
Chartered Semiconductor Manufacturing Ltd., Singapore, SG;
Abstract
In accordance with the objectives of the invention a new method is provided for creating air gaps in a layer of IMD. First and second layers of dielectric are successively deposited over a surface; the surface contains metal lines running in an Y-direction. Trenches are etched in the first and second layer of dielectric in an X and Y-direction respectively. The trenches are filled with a layer of nitride and polished. A thin layer of oxide is deposited over the surface of the second layer of dielectric. Openings are created through the thin layer of oxide that align with the points of intersect of the nitride in the trenches in the layers of dielectric. The nitride is removed from the trenches by a wet etch, thereby opening trenches in the layers of dielectric with both sets of trenches being interconnected. The openings in the thin layer of oxide are closed, leaving a network of trenches containing air in the two layers of dielectric.