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:
Aug. 12, 1997
Filed:
Jun. 26, 1995
David J Leary, Ft. Collins, CO (US);
Hewlett-Packard Co., Palo Alto, CA (US);
Abstract
An electrostatic discharge device having a small separation between two traces wherein a voltage above a desired threshold will discharge across the separation through the mechanism of cold cathode electric field emission. Conditions which permit quantum mechanical tunneling of electrons across the emitting cathode/vacuum potential barrier, such as low emitter work function, electric field enhancing geometry, and cathode/anode separation size, determine the voltage necessary for discharge by this mechanism. One device has a first conductive trace formed on an insulating layer and then masked and etched to leave an undercut with a sharp point. A second conductive trace is formed in the undercut opposite the point, resulting in a three-dimensional cross section having a very small separation. A second device has the point formed by depositing a metal layer over a spacing in a dielectric layer, and then etching out the dielectric layer.