In situ estimation of blanket polish rates and wafer-to-wafer variation

Author

Patel, Nital S. ; Miller, Gregory A. ; Jenkins, Steven T.

Author_Institution

Texas Instrum. Inc., Dallas, TX, USA

Volume

15

Issue

4

fYear

2002

fDate

11/1/2002 12:00:00 AM

Firstpage

513

Lastpage

522

Abstract

Presents a scheme for extracting information from interferometry signals off patterned wafer polish during nonendpointed chemical-mechanical polishing (CMP). This enables one to obtain blanket removal rates immediately after a patterned wafer finishes polishing as well as estimate post-polish within lot thickness variation. A nonlinear regression algorithm is presented that enables one to estimate this information from less than a full interferometry trace cycle and with a lower sampling rate compared to peak-valley detection schemes.

Keywords

chemical mechanical polishing; light interferometry; planarisation; process control; statistical analysis; blanket polish rates; blanket removal rates; interferometry signals; interferometry trace cycle; lot thickness variation; nonendpointed chemical-mechanical polishing; nonlinear regression algorithm; post-polish estimation; sampling rate; wafer-to-wafer variation; Chemicals; Data mining; Interferometry; Metrology; Observability; Optical films; Process control; Production; Robustness; Sampling methods;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/TSM.2002.804900

Filename

1134169