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of metal thickness, non-uniformity, and copper patches allows for dynamic feedback control during CMP and results in a sharp and reliable copper-clear endpoint. The in-situ endpoint system shortens process development cycle, eliminates underpolishing, and reduces overpolishing to increase yield. Multi-angle reflectometry allows the endpointer to support other CMP applications: shallow trench isolation (STI) and tungsten processes. Single angle reflectometry has been tried for STI, but the reflectance signal feature that signifies endpoint is not unique. Such endpointers depend critically on timing parameters and knowledge of incoming film thickness. Any problem upstream of the CMP process affects endpoint timing accuracy. In positive contrast, the PRECICE system manipulates its angular spectrum reflectometry data to extract a signal feature unique to STI polish endpoint. Thus, it supports a CMP process independent of layer thickness variation from prior deposition steps.
References 1. C.L. Mallory, W. Johnson, and K. Lehman, “Eddy current test method and apparatus,� U.S. Patent No. 5,552,704, September 3, 1996. 2. R.C. McMaster, P. McIntire, and M.L. Mester eds. Nondestructive Testing Handbook: Electromagnetic Testing, 2nd edn., American Society for Nondestructive Testing, 1986. 3. J.D. Jackson. Classical Electrodynamics, 3rd edn., New York: Wiley, 1998. 4. R.M.A Azzam and N.M. Bashara. Ellipsometry and Polarized Light, Amsterdam: North-Holland, 1992. 5. D. H. Ballard and C.M. Brown. Computer Vision, Englewood Cliffs, NJ: Prentice-Hall, 1982. 6. M. Basseville and I.V. Nikoforov. Detection of Abrupt Changes: Theory and Application, Englewood Cliffs, NJ: Prentice-Hall, 1993. A version of this article was originally published in the 2001 ISSM/IEEE proceedings International Symposium of Semiconductor Manufacturing Conference, October 8-10, 2001, San Jose, California, USA.
KLA-Tencor Trade Show Calendar January 30, 2002
YMS China, Shanghai, China
February 5-7
SEMICON Korea, Seoul, Korea
February 11-15
AVS, Santa Clara, California
March 3
Lithography Users Group Meeting, Santa Clara, California
March 5-6
SPIE/Microlithography, Santa Clara, California
March 26
SEMICON China, Shanghai, China
April 10-12
ACE/APC, Dresden, Germany
April 16-18
SEMICON Europa, Munich, Germany
April 17
YMS Europa, Munich, Germany
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Fall 2001 Yield Management Solutions