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:
Jan. 09, 1979
Filed:
May. 16, 1977
Douglas P Simms, Sunnyvale, CA (US);
Anthony F White, Cupertino, CA (US);
Carl W Miller, Santa Clara, CA (US);
The Computervision Corporation, Bedford, MA (US);
Abstract
A non-contacting, non-clogging, electro-mechanically operated marking device or inker for continuous or intermittently marking a semiconductor wafer die is disclosed together with a method of operating the device. The marking device has an ambient pressure ink reservoir within which is mounted a thin, capillary filament guide tube. A length of filament such as, fishline, is positioned within the tube and secured at one end to the plunger of a solenoid. The distal end of the filament is driven out of the capillary tube by the solenoid to force a small amount of the marking fluid or ink out of the reservoir and onto the die without the filament contacting the die. The solenoid coil is energized by a current pulse having a first current level and a second current level that is less than the first current level. The second current level provides a short holding current for the solenoid to prevent spattering of the marking fluid.