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. 09, 2018
Filed:
Sep. 14, 2017
Cymer, Llc, San Diego, CA (US);
Tanuj Aggarwal, San Diego, CA (US);
Cymer, LLC, San Diego, CA (US);
Abstract
A method and apparatus for controlling a dose of radiation generated by a laser light source is disclosed. In one embodiment, a dose controller receives measurements of the deviation of output energy from an expected output energy, or 'energy sigma,' and the standard deviation of the error in the dose received by the item being processed from the desired dose. The ratio of the energy sigma to the standard deviation of dose error is calculated, and the laser controller adjusts the controller gain based upon the calculated ratio so as to adjust the voltage determined by the controller, and consequently the output energy and thus the dose to the item. This is an improvement over the prior art, in which the controller gain is adjusted based upon sending a voltage dither to the laser and correlating it to its response in energy at only one frequency.