CF4 radio-frequency (rf) plasmas are often driven in time-modulation modes to obtain higher etching performance. For dynamic and stable control of CF4 plasmas, we investigated the transient behaviour of the plasmas after step up or down of the amplitude of the power source voltage Vs(t). Using a one-dimensional fluid model, we simulated a CF4 capacitively coupled plasma that transfers from a periodic steady state to another at 0.2 Torr in a 20 mm parallel-plate gap. In addition, we compared such plasma responses to the step down to 0 V at the phases at which Vs(t) takes zero and peak values. Fundamental properties of transient CF4 plasmas were discussed.

CF4 radio frequency (rf) (13.56 MHz) capacitively coupled plasmas were simulated using a two-dimensional fluid model of cylindrical symmetry. We investigated their periodic steady state and transient behaviour after step changes of the amplitude of a power source voltage. The results were compared with those obtained by a one-dimensional model. The two-dimensional model showed that the plasmas in a harmonic steady state have asymmetric profiles due to generation of a dc self-bias through an asymmetric electrode system with grounded wall. The transient response of the plasmas in the two-dimensional model was qualitatively similar to those of the one-dimensional model except in the powered electrode edge region where the radial component of the electric field was significant.

A new adaptive fuzzy controller for uncertain based backstepping controller have enlarged the class of strict-feedback nonlinear systems is proposed. All the previous nonlinear systems that can be applicable. However, there are approximator-based adaptive control algorithms for the strict-some problems in the previous adaptive approximator-based feedback nonlinear systems are based on backstepping scheme controllers based on backstepping design method. First, some and guarantee semi-global closed-loop system stability. This paper proposes a new globally stabilizing adaptive fuzzy controller very tedious and complex analysis iS needed to determine for strict-feedback nonlinear system without backstepping. To regression matrices, virtual controls and their time derivatives. this end, an online self-structuring adaptive fuzzy system is The complexity exhibits an exponential increase progression as employed. The proposed adaptive fuzzy controller is considerably the dynamic order of the controlled system grows. In [18], this simpler than the previous ones based on backstepping. Only one FLS is employed to approximate a lumped uncertain nonlinearity, problem is overcome by viewing the original control problem which highlights the simplicity of our proposed control scheme. of the strict-feedback system as that of a normal system.Second, all the previous controllers guarantee the stability of

Al:ZnO thin films were deposited using the radio frequency magnetron sputtering technique at various temperaturesand sputtering powers. With the increase in the deposition temperature and the decrease in the radio frequencysputtering power, the crystallinity was increased and the surface roughness was decreased, which lead to the decreasein the electrical resistivity of the film. It is also clearly observed that, the intensity of the (002) XRD peak increases withincreasing the substrate temperature [1,2]. The electrical resistivity and optical transmittance of the Al:ZnO thin filmwere analyzed as a function of the post-annealing temperature. It can be seen that with the annealing temperature setat 400℃, the resistivity decreases to a minimum value of 4.1×10-3 Ωcm and the transmittance increases to a maximumvalue of 85% of the Al:ZnO thin film

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