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:
Dec. 30, 1997
Filed:
Aug. 26, 1996
Shu-Lan Ying, Hsin-Chu, TW;
Yuan-Chang Huang, Hsin-Chu, TW;
Jue-Jye Chen, I-Lan, TW;
Yuh-Jier Mii, Taipei, TW;
Taiwan Semiconductor Manufactoring, Company Ltd, Hsin-Chu, TW;
Abstract
The present invention provides a test site on a product wafer for measuring via etch depth and a method of monitoring the depth of the vias using the test site. A substrate is provided having a test site area and a circuit area. A test site via is formed in the test site area. The test site via is used in measuring the depth of the insulating layers remaining in a test site via and the depth of the test site via. The measurements are taking using an in-line non-destructible measurement tool, such as an ellipsometer or spectrophotometer. The test site is specifically designed to be large enough to have the via depth measured by an in-line measuring tool. The depth of the oxide remaining in the test site via is measured after the via etch and is correlated to the amount of titanium nitride removed from the tops of the metal lines in the circuit areas. The via etch process is then adjusted to center the via etch at the optimum point to ensure that enough the vias are deep enough without removing too much of the top barrier layer (e.g., titanium nitride) film over the metal lines.