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. 07, 2004
Filed:
Oct. 22, 2002
Timothy M. Barry, Colleyville, TX (US);
Nicolas Degors, Trets, FR;
Donald A. Erickson, Dallas, TX (US);
Amit S. Kelkar, Irving, TX (US);
Bradley J. Larsen, Woodland Park, CO (US);
Atmel Corporation, San Jose, CA (US);
Abstract
A method for fabricating a shallow trench isolation structure is described, in which a bottom pad oxide layer, a middle silicon nitride layer, a middle oxide layer and a top silicon nitride layer are sequentially formed on a silicon substrate. Photolithographic masking and anisotropic etching are then conducted to form a trench in the substrate. An oxide material is then deposited on top of the top silicon nitride layer, filling up the trenches at the same time. A chemical mechanical polishing step is then employed to remove the oxide material by using the top silicon nitride layer as a barrier layer. The top silicon nitride layer is then removed, followed by an isotropic etch of the oxide layer below. With the middle nitride layer acting as a natural etch stop, the oxide material is sculpted to a desirable shape. The middle nitride layer and the pad oxide layer are subsequently removed to complete the fabrication of a shallow trench isolation structure.