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. 15, 2011
Filed:
Oct. 31, 2008
Che Ta Hsu, San Jose, CA (US);
Peter J. Mcelheny, Morgan Hill, CA (US);
Jeffrey T. Watt, Palo Alto, CA (US);
Che Ta Hsu, San Jose, CA (US);
Peter J. McElheny, Morgan Hill, CA (US);
Jeffrey T. Watt, Palo Alto, CA (US);
Altera Corporation, San Jose, CA (US);
Abstract
Photolithographic reticles are provided that have electrostatic discharge protection features. A photolithographic reticle may be formed from metal structures such as chrome structures on a transparent substrate such as fused silica. Some of the metal structures on the reticle correspond to transistors and other electronic devices on integrated circuits that are fabricated when using the reticles in a step-and-repeat lithography tool. These metal device structures may be susceptible to damage due to electrostatic charge build up during handling of the reticle. To prevent damage, dummy ring structures are formed in the vicinity of device structures. The dummy ring structures may be constructed to be more sensitive to electrostatic discharge than the device structures, so that in the event of an electrostatic discharge, damage is confined to portions of the reticle that are not critical.