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:
Nov. 30, 1999
Filed:
Dec. 17, 1997
Gurtej S Sandhu, Boise, ID (US);
Richard L Elliott, Boise, ID (US);
Trung T Doan, Boise, ID (US);
Jody D Larsen, Boise, ID (US);
Micron Technology Inc., Boise, ID (US);
Abstract
The present invention relates to integrated circuits (ICs) fabrication. Particularly, there is a cmp process which incorporates small quantities of two chemicals. The first chemical is the standard slurry mixtures, like water, aluminum-oxide and hydrogen-peroxide mixed into a slurry. The second chemical is a strong base chemical, like KOH, or potassium hydroxide. Moreover, the cmp process utilizes a system of closely regulating the timing of the two chemical process. Specifically, during a first time period, both chemicals are applied; thus increasing speed of the chemical removal of tungsten material. During a second time period, the KOH is removed, thus slowing down the chemical action and importantly achieving a greater degree of planerization than is capable by the two chemical first time period.