Control of semiconductor manufacturing equipment: real-time feedback control of a reactive ion etcher

This paper describes the development of real-time control technology for the improvement of manufacturing characteristics of reactive ion etchers. A general control strategy is presented. The principal ideas are to sense key plasma parameters, develop a dynamic input-output model for the subsystem connecting the equipment inputs to the key plasma variables, and design and implement a multivariable control system to control these variables. Experimental results show that this approach to closed-loop control leads to a much more stable etch rate in the presence of a variety of disturbances as compared to current industrial practice. >

[1]  Michael T. Mocella,et al.  The Plasma Etching of Polysilicon with CF 3Cl / Argon Discharges I . Parametric Modeling and Impedance Analysis , 1986 .

[2]  D. Manos,et al.  Plasma etching : an introduction , 1989 .

[3]  Pramod P. Khargonekar,et al.  Real-time control of reactive ion etching: identification and disturbance rejection , 1993, Proceedings of 32nd IEEE Conference on Decision and Control.

[4]  S. Balemi,et al.  Supervisory control of a rapid thermal multiprocessor , 1993, IEEE Trans. Autom. Control..

[5]  Mehrdad M. Moslehi,et al.  Modeling, Identification, and Control of Rapid Thermal Processing Systems , 1994 .

[6]  Tyrone L. Vincent,et al.  Real-time feedback control of reactive ion etching , 1994, Other Conferences.

[7]  Daniel L. Flamm,et al.  Computer simulation of a CF4 plasma etching silicon , 1984 .

[8]  James Moyne,et al.  A generic cell controller for the automated VLSI manufacturing facility , 1992 .

[9]  Vincent M. Donnelly,et al.  Optical emission actinometry and spectral line shapes in rf glow discharges , 1984 .

[10]  Jessy W. Grizzle,et al.  Phenomenological modeling of plasma generation for real-time control of RIE systems , 1994, Proceedings of International Workshop on Numerical Modeling of processes and Devices for Integrated Circuits: NUPAD V.

[11]  Thomas F. Edgar,et al.  Development of Techniques for Real‐Time Monitoring and Control in Plasma Etching II . Multivariable Control System Analysis of Manipulated, Measured, and Performance Variables , 1991 .

[12]  B. A. Rashap,et al.  Real-time feedback for sidewall profile control in reactive ion etching , 1995 .

[13]  Stephanie Watts Butler Etching and Polymerization in Fluorocarbon-Hydrogen Plasmas: Mathematical Modeling and Experimental Investigation. , 1991 .

[14]  R. S. Gyurcsik,et al.  A model for rapid thermal processing: achieving uniformity through lamp control , 1991 .

[15]  G. Stein,et al.  Multivariable feedback design: Concepts for a classical/modern synthesis , 1981 .

[16]  Anne Simmons,et al.  Plasma processing of materials: Scientific opportunities and technological challenges , 1991 .

[17]  Costas J. Spanos Statistical process control in semiconductor manufacturing , 1992 .

[18]  P. T. Kabamba,et al.  Applications of Control to Semiconductor Manufacturing: Reactive Ion Etching , 1993, 1993 American Control Conference.

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

[20]  Herbert H. Sawin,et al.  Monitoring and Control of Real Power in RF Plasma Processing , 1991 .

[21]  S. Wolf,et al.  Silicon Processing for the VLSI Era , 1986 .

[22]  K. J. McLaughlin,et al.  Real-time monitoring and control in plasma etching , 1991, IEEE Control Systems.

[23]  Dale E. Seborg,et al.  An Adaptive Nonlinear Control Strategy for Photolithography , 1993, 1993 American Control Conference.

[24]  B. A. Rashap,et al.  Nonlinear system identification and control of a reactive ion etcher , 1994, Proceedings of 1994 American Control Conference - ACC '94.

[25]  Michael Lane Passow Microwave, RF and hybrid reactor generated discharges for semiconductor processing. , 1991 .