Paper
14 June 1999 Algorithm implementation and techniques for providing more-reliable overlay measurements and better tracking of the shallow-trench isolation (STI) process
Author Affiliations +
Abstract
This paper presents the result of a new algorithm designed to improve the success rate, precision and accuracy of the measurements for low contrast targets produced by STI. The paper will also review the algorithm and discuss the result of target design optimization. Results will be provided from multiple lots with multiple wafer analysis demonstrating the effectiveness of the algorithm. Measurement yields improve from the 35 percent-50 percent success rate using current algorithms to 99 percent-100 percent success rate using the new algorithm. Precision was improved from 10nm to 3nm, and as low as 1.2 nanometers 3(sigma) . The true success of the algorithm is not just the improved measurement success, precision and accuracy; but it is in the verification that the edges are detected and measured accurately. Many current algorithms are giving estimates.
© (1999) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Doug Schramm, Dale Bowles, Martin E. Mastovich, Paul C. Knutrud, and Anastasia Tyurina "Algorithm implementation and techniques for providing more-reliable overlay measurements and better tracking of the shallow-trench isolation (STI) process", Proc. SPIE 3677, Metrology, Inspection, and Process Control for Microlithography XIII, (14 June 1999); https://doi.org/10.1117/12.350798
Lens.org Logo
CITATIONS
Cited by 1 scholarly publication and 8 patents.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Detection and tracking algorithms

Semiconducting wafers

Chemical mechanical planarization

Oxides

Overlay metrology

Silicon

Wafer-level optics

RELATED CONTENT


Back to Top