This paper proposes a robust double‐integral T‐S fuzzy output regulator design for affine nonlinear systems in the presence of parametric uncertainty and external disturbance. First, we adopt double integrators (an error integrator and an input integrator) to obtain an augmented T‐S fuzzy model representation which has a common input matrix of fuzzy rules. This property yields less stability conditions. Next, by introducing a set of virtual desired variables (VDVs), a double‐integral VDV‐based fuzzy regulator is proposed to cope with unknown bias and to achieve asymptotical output regulation. Afterward, the controller is simplified to avoid VDV calculation and enhance robustness to uncertainty and external disturbance. In contrast to traditional regulation design, the double‐integral non‐VDV fuzzy regulator design reduces the number of fuzzy controller rules and stability LMIs. Moreover, the error coordinate transformation is removed and the uncertainty is allowed in this paper. Finally, a DC/DC buck converter system is taken as the example to demonstrate the expected performance.

This work develops an alternative method, selective liquid‐phase deposition (S-LPD), to fabricate contact holes instead of reactive ion etching. In preliminary experiments, deep n+/normalp junction diodes with contact holes prepared by S-LPD exhibit much less reverse current, unity ideality factor, larger forward current, lower contact resistance, and higher thermal stability than those prepared by reactive ion etching. Further superiority of plasma damage‐free near‐surface regions is also investigated using Schottky and ultra‐shallow junction diodes. Experimental results indicate that S-LPD can be applied to the submicron contact‐hole process. The data after reverse bias temperature stress reveals the satisfactory reliability of S-LPD contact holes. This work demonstrates that the S-LPD technology is a highly promising means of replacing reactive ion etching processes to form submicron contact holes as reliably as those by wet‐etching. © 1999 The Electrochemical Society. All rights reserved.

Purpose -The purpose of this paper is to develop the multi-degree-of-freedom measurement system to test, verify, and control the nano-measuring machine. Design/methodology/approach -A generic differential model approach is constructed to numerically describe the hysteresis effects of piezoelectric actuators. Based on the generic differential model, a feedforward compensator with a proportional integral (PI) type controller is designed to compensate for the hysteresis nonlinearity of a piezoelectric actuated three degree-of-freedom coplanar nanostage which can provide high-precision applications. Findings -The Z-tilts (z, pitch, and roll motion) error compensation stage of the nano-measuring machine is accomplished. Moreover, a high-resolution laser interferometer is used to measure position accurately. Originality/value -This paper contributes to develop a tracking control design method for the piezoelectric motion platform which combines a closed-loop feedforward compensator with a PI type controller.