Real-time estimation of patterned wafer parameters using in situ spectroscopic ellipsometry

Author

Galarza, Cecilia G. ; Khargonekar, Pramod P. ; Terry, Fred L., Jr.

Author_Institution

Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA

Volume

1

fYear

1999

fDate

1999

Firstpage

773

Abstract

We analyze the problem of real-time thickness estimation for patterned wafers during an etching process using in situ spectroscopic ellipsometry. For that, a two-stage estimation algorithm is proposed. The first stage is an automatic model calibration algorithm that uses the data collected during an initial interval. The second stage is a nonlinear state estimation system designed for the tuned model. We study the sensitivity of this estimation strategy to variations in the wafer parameters and the process conditions

Keywords

ellipsometry; etching; integrated circuit manufacture; nonlinear systems; parameter estimation; process control; real-time systems; state estimation; thickness control; IC manufacture; etching process; model calibration; nonlinear system; parameter estimation; patterned wafers; real-time systems; sensitivity; spectroscopic ellipsometry; state estimation; thickness estimation; Calibration; Ellipsometry; Etching; Manufacturing processes; Microelectronics; Nonlinear dynamical systems; Robustness; Semiconductor device modeling; Spectroscopy; State estimation;

fLanguage

English

Publisher

ieee

Conference_Titel

Control Applications, 1999. Proceedings of the 1999 IEEE International Conference on

Conference_Location

Kohala Coast, HI

Print_ISBN

0-7803-5446-X

Type

conf

DOI

10.1109/CCA.1999.807759

Filename

807759