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A systematic procedure for performance assessment and PI/PID controller design based on modified relay feedback test is proposed in this paper. It can estimate the gain and phase margins of unknown systems on-line to indicate the appropriateness of the controller parameters. When the retuning of controller is found necessary, the proposed modified relay(More)
A new nonparametric approach to identify multivariable Hammerstein models is presented in this paper. The linear dynamic subsystem is identified and represented by its finite impulse response (FIR) model, and, the static nonlinearity is identified and represented as an MIMO input-output mapping. By specially designed test signals, the estimation of FIRs for(More)
A two-step design t o control integrator processes in an SISO or MIMO system is proposed. For an SISO system, the first step of the design is to stabilize the integrator process with P&D modes in a secondary loop to achieve good stability robustness and modest performance. In the second step of design, a P&I controller in the primary loop is derived to(More)
Fig. 2. Change of thermal budget shape as the line width getting narrower. (a) soak (b) spike. Abstract: Rapid thermal processing (RTP) systems with spike-shaped temperature profile is widely used in IC industry for providing precise thermal budgets. This thermal budget control issue gets more crucial as the technology node progressively shrinking. With its(More)
The quality control of the wafer is becoming more and more important as the wafer becomes larger and the feature size shrinks. An advanced IC fabrication process consists of 300+ steps with scarce and usually difficult quality measurements. Thus product yield may not be realized until months into production while in-line measurements are available on the(More)
A performance assessment procedure for single-input-single-output (SISO) and multi-input-multi-output (MIMO) systems based on modified relay feedback test is proposed in this paper. The well-known robustness measurements, gain and phase margins, are used to assess the performance of the control systems. The proposed method can on-line estimate the gain and(More)
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