Run-by-Run Process Control of Metal Sputter Deposition: Combining Time Series and Extended Kalman Filter

By the time series model, this paper constructed the disturbance model for the aluminum sputter deposition process and derived the extending Kalman filter (EKF) controller based on this new disturbance model. Experimental results reveal that ARI(3,1) model appropriately characterizes the dynamic behavior of the disturbance for the processes. The EKF controller which includes information of process noise and measurement noise is able to regulate the model coefficients automatically as the target is replaced or degrades. In this paper, the d-EWMA controller, time-varying d-EWMA controller, age-based d-EWMA controller, and EKF controller have been applied to aluminum sputter deposition processes for predicting deposition rates and comparing their performances. The application of the EKF controller here is proven to improve the estimating accuracy of the aluminum sputter deposition process significantly, regardless of whether the deposition rates are measured at each run or not.

[1]  Armann Ingolfsson,et al.  Run by run process control: combining SPC and feedback control , 1995 .

[2]  S. W. Butler,et al.  Supervisory run-to-run control of polysilicon gate etch using in situ ellipsometry , 1994 .

[3]  Costas J. Spanos,et al.  Real-time statistical process control using tool data (semiconductor manufacturing) , 1992 .

[4]  L. Sattler,et al.  Reducing costs and increasing throughput using model-based process control on sputtering systems , 1998, Twenty Third IEEE/CPMT International Electronics Manufacturing Technology Symposium (Cat. No.98CH36205).

[5]  P. Young,et al.  Time series analysis, forecasting and control , 1972, IEEE Transactions on Automatic Control.

[6]  Duane S. Boning,et al.  A self-tuning EWMA controller utilizing artificial neural network function approximation techniques , 1996, Nineteenth IEEE/CPMT International Electronics Manufacturing Technology Symposium.

[7]  Fugee Tsung,et al.  A study of variable EWMA controller , 2003 .

[8]  Ruey-Shan Guo,et al.  Process control system for VLSI fabrication , 1991 .

[9]  Ruey-Shan Guo,et al.  A self—tuning run—by—run process controller for processes subject to random disturbances , 1999 .

[10]  A. Corigliano,et al.  Parameter identification in explicit structural dynamics: performance of the extended Kalman filter , 2004 .

[11]  Ruey-Shan Guo,et al.  Run-to-run control schemes for CMP process subject to deterministic drifts , 2000, 2000 Semiconductor Manufacturing Technology Workshop (Cat. No.00EX406).

[12]  Ruey-Shan Guo,et al.  Age-based double EWMA controller and its application to CMP processes , 2001 .

[13]  Chun-Chin Hsu,et al.  A time-varying weights tuning method of the double EWMA controller , 2004 .

[14]  Duane S. Boning,et al.  Run by run advanced process control of metal sputter deposition , 1998, ICMTS 1998.