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. 21, 2003
Filed:
Feb. 19, 2002
Andrew M. Hawryluk, Los Altos Hills, CA (US);
Somit Talwar, Palo Alto, CA (US);
Yun Wang, San Jose, CA (US);
Michael O. Thompson, Ithaca, NY (US);
Ultratech Stepper, Inc., San Jose, CA (US);
Abstract
Method for controlling heat transferred to a workpiece (W) process region ( ) from laser radiation ( ) using a thermally induced reflectivity switch layer ( ). A film stack ( ) is formed having an absorber layer ( ) atop the workpiece with a portion covering the process region. The absorber layer absorbs and converts laser radiation into heat. Reflective switch layer ( ) is deposited atop the absorber layer. The reflective switch layer comprises one or more layers, e.g. thermal insulator and reflectivity transition layers. The reflective switch layer covering the process region has a temperature related to the temperature of the process region. Reflectivity of the switch layer changes from a low to a high reflectivity state at a critical temperature of the process region, limiting radiation absorbed by the absorber layer by reflecting incident radiation when switched. This limits the amount of heat transferred to the process region from the absorber layer.