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. 13, 1990
Filed:
Sep. 29, 1989
Applicant:
Inventors:
Clarence J Tracy, Tempe, AZ (US);
John L Freeman, Jr, Mesa, AZ (US);
Robert L Duffin, Mesa, AZ (US);
Anthony Polito, Mesa, AZ (US);
Assignee:
Motorola, Inc., Schaumburg, IL (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01L / ;
U.S. Cl.
CPC ...
437187 ; 437188 ; 437197 ; 437246 ; 437247 ; 148D / ;
Abstract
Metal step coverage is improved by utilizing a multiple step metallization process. In the first step, a thick portion of a metal layer is deposited on a semiconductor wafer at a cold temperature. The remaining amount of metal is deposited in a second step as the temperature is ramped up to allow for reflow of the metal layer through grain growth, recrystallization and bulk diffusion. The thick portion of the metal layer deposited at the cold temperature is of adequate thickness so that it remains continuous at the higher temperature and enhances via filling.