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. 18, 2000
Filed:
Nov. 05, 1998
Chin-Hung Tseng, Hsinchu, TW;
United Silicon Incorporated, Hsinchu, TW;
Abstract
A method of manufacturing a shallow trench isolation alignment mark comprises the steps of first providing a silicon wafer whose surface has an alignment mark formed thereon. Next, a silicon nitride layer is formed over the silicon wafer, and then shallow trenches are formed. At least one of the shallow trenches is positioned at a distance of about 2000 .ANG. to 10000 .ANG. from the edge of the alignment mark. Thereafter, an oxide layer is formed over the silicon nitride layer, and then a chemical-mechanical polishing operation is conducted to remove a portion of the oxide layer and silicon nitride layer above the alignment mark. Altogether, a layer of silicon nitride having a thickness of about 600 .ANG. is removed from the top of the alignment mark. Finally, the silicon nitride layer is also removed. By forming a shallow trench at a distance of between 2000 .ANG. to 10000 .ANG. from the edge of an alignment mark, accurate overlaying of mask can be achieved without the need for performing additional oxide clearout operations.