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:
Jul. 03, 2001
Filed:
Jun. 24, 1999
Emmanuel Perrin, Biviers, FR;
Frédéric Robert, Ambares, FR;
Henri Banvillet, Froges, FR;
Luc Liauzu, Grenoble, FR;
STMicroelectronics, S.A., Gentilly, FR;
Abstract
A process for polishing, on a polishing machine and under defined polishing conditions, the external surface of at least one wafer of integrated circuits comprising a projecting feature covered over the entire surface of the wafer with an external layer of a material, consisting in calculating a main equivalent thickness equal to the main surface density of the projecting feature multiplied by the thickness of the latter; in polishing, under the defined polishing conditions, a reference wafer comprising an external layer of the material, having a uniform thickness and covering the surface of this reference wafer, so as to determine the rate of removal by the polishing machine corresponding to the ratio of the thickness removed to the polishing time elapsed; in calculating a polishing time equal to the ratio of the aforementioned equivalent thickness to the aforementioned rate of removal; in calculating a total equivalent thickness equal to the sum of the main equivalent thickness and of a complementary thickness of preset value; in calculating a polishing time equal to the ratio of this total-equivalent thickness to the aforementioned rate of removal; and in carrying out, under the polishing conditions, the polishing operation on at least one wafer to be polished for a duration which is equal to the aforementioned polishing time or which depends on this time.