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:
Jun. 06, 1995
Filed:
Sep. 21, 1992
Ajit P Paranjpe, Plano, TX (US);
Phillip Chapados, Jr, Plano, TX (US);
Jimmy W Hosch, Dallas, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A test structure and a method of using it for measuring submicron linewidths. Diffraction gratings are made with lines having an unknown linewidth. The grating has a pitch comprises of multiple lines and multiple spaces. This permits a wider 'effective pitch' resulting in an increased number of observable diffraction orders. Each order provides an intensity measurement, which can be substituted into a diffraction intensity equation in which intensity is a function of linewidth and other unknown variables. At least as many intensity measurements are obtained as are unknown variables so that a system of equations can be solved for the linewidth. In practice, if the grating lines are made in the same manner as other lines of a product, the width of the latter can be inferred.