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:
Oct. 24, 1989
Filed:
Aug. 29, 1988
Richard R Phinney, South Hero, VT (US);
David C Strippe, Waterbury Center, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A process for the evaporation deposition of a layer of metal on a workpiece is described in which a charge of a metal is placed in a crucible formed of a material having a vapor pressure lower than the vapor pressure of the metal at a selected temperature, a shield is placed between the workpiece and the crucible, and the crucible is then heated to a first temperature sufficient to melt said charge, but insufficient to cause substantial evaporation of said charge following which the crucible is heated to a second temperature level for a time sufficient to fractionally distill the charge and sublime or vaporize any non-metallic contaminants in said charge and finally the crucible is heated to a third temperature sufficient to evaporate the charge at a selected rate at which time the shield is removed from between the cricuble and the workpiece to permit evaporant from the charge to coat the workpiece.