Title :
Modeling and filtering of optical emission spectroscopy data for plasma etching systems
Author :
Rangan, Sundeep ; Spanos, Costas ; Poolla, K.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., California Univ., Berkeley, CA, USA
Abstract :
Full-spectrum in situ optical emission spectroscopy (OES) has emerged as a promising technology for in-line sensor systems for plasma etching process control. In this paper, we present a novel empirical model-based approach for OES data filtering based on statistical principal component analysis and jump linear filtering. The modeling procedure is demonstrated on a commercial multilayer Al/TiN/SiO2 etch process. For this process, we show that the proposed model provides a succinct representation of the OES signals and is in excellent agreement with the experimental data
Keywords :
atomic emission spectroscopy; data compression; filtering theory; linear systems; optical sensors; parameter estimation; piecewise constant techniques; semiconductor process modelling; sputter etching; state estimation; state feedback; state-space methods; statistical process control; Al-TiN-SiO2; data compression; data filtering; empirical model-based approach; etching process control; feedback control; full-spectrum systems; in situ optical emission spectroscopy; in-line sensor systems; interacting multimodel filter; iterative algorithm; jump linear filtering; linear dynamical system output; multilayer Al/TiN/SiO2 etch process; parameter estimation; piecewise constant input; plasma etching systems; state estimation; statistical principal component analysis; subspace identification; two-state jump linear model; Etching; Filtering; Nonlinear filters; Optical filters; Optical sensors; Plasma applications; Process control; Sensor systems; Spectroscopy; Stimulated emission;
Conference_Titel :
Semiconductor Manufacturing Conference Proceedings, 1997 IEEE International Symposium on
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-3752-2
DOI :
10.1109/ISSM.1997.664507
