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:
Nov. 07, 2023
Filed:
Apr. 15, 2021
Onto Innovation Inc., Wilmington, MA (US);
Nicholas James Keller, La Jolla, CA (US);
George Andrew Antonelli, Portland, OR (US);
Onto Innovation Inc., Wilmington, MA (US);
Abstract
A metrology target is designed for measuring a feature at the bottom of a trench in a device under test, such as a tungsten recess vertical profile in a wordline in a three-dimensional (3D) NAND. The metrology target follows the design rules for the device under test and includes a tier stack with a plurality of tier stack pairs including, each including a conductor layer, such as tungsten, and an insulator layer, such as silicon dioxide and a trench that extends through the tier stack pairs. The metrology target includes a via that extends through the tier stack pairs and is positioned a lateral distance to the trench to promote access of light to a bottom of the trench, via plasmonic resonance, for measurement of a characteristic of the trench, such as the tungsten recess at the bottom of the wordline slit.