Share Email Print

Proceedings Paper

Integrated ODP metrology with floating n&k's for lithography process
Author(s): Patrick Kearney; Dmitriy Likhachev; Junichi Uchida; Göran Fleischer
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Advanced DRAM manufacturing demands rigorous and tight process control using high measurement precision, accurate, traceable and high throughput metrology solutions. Scatterometry is one of the advanced metrology techniques which satisfies all the above mentioned requirements and it has been implemented in semiconductor manufacturing for some time for monitoring and controlling critical dimensions and other important structural parameters. One of the major contributions to the optical critical dimensions metrology uncertainty is the variations in optical properties (n&k's) of film stack materials. And it is well-known that the optical properties of materials depend very much on process conditions (such as operating conditions of deposition tools). However, in traditional scatterometry approach all the n&k's have been used as fixed inputs in a scatterometry model which might result in significant metrology error. This paper shows the use of the integrated scatterometry system in a real production environment. The significant improvement in accuracy of CD data was achieved following the implementation of new floating n&k's option for the Optical Digital Profilometry (ODPTM) system. It has been clearly shown that to achieve desired sub-nanometer accuracy in scatterometry measurements for advanced processes we need to pay scrupulous attention to every detail of the scatterometry modeling and measurement. Still further work is needed to better understand the impact of n&k's variations on tool-to-tool matching.

Paper Details

Date Published: 23 March 2009
PDF: 9 pages
Proc. SPIE 7272, Metrology, Inspection, and Process Control for Microlithography XXIII, 727241 (23 March 2009); doi: 10.1117/12.814246
Show Author Affiliations
Patrick Kearney, Tokyo Electron Europe Ltd. (Germany)
Dmitriy Likhachev, Timbre Technologies, Inc. (United States)
Junichi Uchida, Tokyo Electron Europe Ltd. (Germany)
Göran Fleischer, Qimonda Dresden GmbH & Co. OHG (Germany)

Published in SPIE Proceedings Vol. 7272:
Metrology, Inspection, and Process Control for Microlithography XXIII
John A. Allgair; Christopher J. Raymond, Editor(s)

© SPIE. Terms of Use
Back to Top