| US 7,348,192 B2 | ||
| Method for monitoring film thickness, a system for monitoring film thickness, a method for manufacturing a semiconductor device, and a program product for controlling film thickness monitoring system | ||
| Toru Mikami, Kanagawa (Japan) | ||
| Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan) | ||
| Filed on Sep. 03, 2004, as Appl. No. 10/933,441. | ||
| Claims priority of application No. P2003-314626 (JP), filed on Sep. 05, 2003. | ||
| Prior Publication US 2005/0095730 A1, May 05, 2005 | ||
| Int. Cl. H01L 21/66 (2006.01) | ||
| U.S. Cl. 438—16 | 6 Claims |
| 1. A method for monitoring a thickness of an uppermost film deposited on an underlying multi-layer structure, the underlying
multi-layer structure comprising a plurality of thin films formed on a substrate, the method comprising:
determining thickness data of each of the thin films of the underlying multi-layer structure before the uppermost film is
formed on the underlying multi-layer structure, and storing the thickness data of the thin films of the underlying multi-layer
structure in a thickness memory;
measuring an optical spectrum profile of the uppermost film after the uppermost film is formed on the underlying multi-layer
structure;
reading the thickness data of each of the thin films of the underlying multi-layer structure from the thickness memory;
calculating a plurality of theoretical optical spectrum profiles of the uppermost film based upon corresponding candidate
film thicknesses of the uppermost film, using a measurement recipe for the uppermost film and the thickness data of each of
the thin films of the underlying multi-layer structure; and
searching one of the theoretical profiles of the optical spectrum of the uppermost film, which is closest to the measured
optical spectrum profile of the uppermost film so as to determine a thickness of the uppermost film by the closest theoretical
profile.
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