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. 01, 1992
Filed:
Jun. 05, 1991
Xiao-Chun Mu, Saratoga, CA (US);
Jagir Multani, Fremont, CA (US);
Intel Corporation, Santa Clara, CA (US);
Abstract
An etchback process for etching a refractory metal layer formed on a semiconductor substrate with a greatly reduced micro-loading effect. The etch proceeds in three steps. The first step is a uniform etch which utilizes a gas chemistry of SF.sub.6, O.sub.2 and He and proceeds for a predetermined time to remove most of the metal layer. The second step is a very uniform etch which utilizes a gas chemistry of SF.sub.6, Cl.sub.2 and He and proceeds until the endpoint is detected. The endpoint is detected by measurement and integration of the 772 nm and 775 nm lines of Cl. The third step is a timed etch utilizing a gas chemistry of Cl.sub.2 and He which is used as both an overetch to ensure complete removal of the refractory metal film and as a selective etchant to remove an adhesion underlayer.