To: CMP Community
Date: October 15, 1997.
Subject: Release 1.1 of CMP Characterization Mask Set

We are pleased to announce the revised release, Version 1.1, of the CMP Characterization Mask Set. This Version 1.1 contains only Mask I (area mask) and Mask III (density mask). The new versions for Mask II (pitch mask) and Mask IV (aspect ratio mask) were not included here because they were found to have minimal impact in dielectric CMP processes. We are making these layouts available to the CMP equipment, supplier, and user communities who wish to understand and optimize polish and planarization dependencies as a function of patterns, consumable or equipment sets, and process conditions.

Major Changes from Verion 1.0:

The Version 1.1 includes only Mask I (area mask) and Mask III (density mask). The major change for this version is the expanded die size of 20mm x 20mm. The masks in the previous version (Version 1.0) had the die size of 12mm x 12mm, but the change in increased die size was necessary in order to accomodate the increasing die size in industry. All the structures in each mask remain about the same with some modifications. Please refer to the mask documentation for more details.

Purpose:

The mask set has been designed for the rapid exploration and characterization of the following layout or pattern factors in the CMP of dielectric or other layers: pattern density with fixed pitch and raised area. For each of these, a dedicated die layout has been defined with pattern characteristics taking on a range of values (e.g. pattern densities from 4% to 100%). Each layout consists of a single lithographic layer, and can be used with short-flow wafer fabrication and polishing.

Contents of this Release:

The documentation (with appendix) provides detailed information about each mask and all structures on the masks, recommendations for metrology, and a sample analysis to illustrate the use of measurement information for rapid modeling and characterization of CMP.

Downloading the Release:

The release is being made available via the World Wide Web (www). So that we may track technology transfer, we request that you contact us for the username/password in order to access the distribution. The URL for the distribution is

Masks

If you do not have internet or web access or require an alternative distribution mechanism, please contact us. We can be reached by email; send to boning at mtl.mit.edu.

Participants:

The primary resources for this effort are drawn from MIT (Duane Boning, Jim Chung, Tae Park, Brian Stine, Rajesh Divecha, Dennis Ouma), Sandia National Laboratories (Dale Hetherington), Hewlett-Packard (Sam Nakagawa), and IPEC/Planar (Randy Harwood, Dennis Shy). The above individuals and other participants from these organizations have contributed test structure design expertise, mask layout, mask fabrication, experimental wafer fabrication and measurement resources to test these masks, and analysis methods. We received extremely useful feedback from many expert reviewers in the industry on earlier drafts of the mask set, and we sincerely thank all of these contributors for their insight and comments.

Feedback:

We are interested in potential modifications or enhancements to the characterization mask set design. Future designs and releases are envisioned, and will benefit from community experience using these masks.

Copyrights and Disclaimers

Primary Points of Contact:

Prof. Duane Boning
MIT, Room 39-567
Cambridge, MA 02139
Ph: 617-253-0931 Fax: 617-253-9606
Email: boning at mtl.mit.edu

Prof. James Chung
MIT, Room 39-415
Cambridge, MA 02139
Ph: 617-253-0928 Fax: 617-253-7393
Email: chung@mtl.mit.edu

Dr. Dale Hetherington
Sandia National Labs
Albuquerque, NM 87185-1084
Ph: 505-844-6155 Fax: 505-844-2991
Email: dlhethe@sandia.gov

Last updated October 29, 1997 (D. Boning)
Copyright © 1997 by Massachusetts Institute of Technology. All rights reserved.