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:
Feb. 17, 2009
Filed:
Aug. 07, 2004
David Ziger, San Antonio, TX (US);
David Ziger, San Antonio, TX (US);
NXP B.V., Eindhoven, NL;
Abstract
In an example embodiment, there is a method () for determining an approximately optimal resist thickness comprising providing a first substrate coated with a resist film having a first thickness using a first coat program, (). The first thickness of resist is measured (). A second substrate is provided () and coated with a resist film using the first coat program. The resist film on the second substrate is exposed to radiation. The reflectance spectrum near the actinic wavelength of the resist film is measured (). As a function of the periodicity of the reflectance spectrum, an effective refractive index is determined. Based on the effective refractive index, a periodicity of a swing curve of the resist film coated on the second substrate is determined (). The maxima and minima are determined as a function of the periodicity.