An Extended Kalman filtering-based method of processing reflectometry data for fast in-situ etch rate measurements

Author

Vincent, Tyrone L. ; Khargonekar, Pramod P. ; Terry, Fred L., Jr.

Author_Institution

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

Volume

10

Issue

1

fYear

1997

fDate

2/1/1997 12:00:00 AM

Firstpage

42

Lastpage

51

Abstract

In this paper a new algorithm is presented for determining etch rate from single or multiple wavelength reflectometry data. This algorithm is based on techniques from recursive nonlinear estimation theory-Extended Kalman Filtering. A major advantage of our algorithm is extremely high speed, with computation time less than 1 ms on a Pentium PC. Consequently, it can be used in real-time feedback control applications. The speed advantage also makes it a suitable candidate for full wafer (or multi-point) high-speed etch rate measurement

Keywords

Kalman filters; etching; recursive estimation; reflectometry; semiconductor process modelling; Extended Kalman Filtering; data processing; in-situ high-speed etch rate measurement; multiple wavelength reflectometry; real-time feedback control; recursive nonlinear estimation algorithm; single wavelength reflectometry; Estimation theory; Etching; Feedback control; Filtering; Kalman filters; Optical films; Optical filters; Plasma measurements; Reflectometry; Wavelength measurement;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.554482

Filename

554482