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The temperaturefactor is introduced in modeling progress, based on double nozzle baffle electro-hydraulic servo valve torque motor. A new temperature model of air gap reluctance and polarization magnetomotive force was proposed. And an accurate magnetic flux computing method was deduced, in order to provide the basis for the establishment of a new torque motor model and the servo valve temperature characteristic analysis.

A hybrid model, which consists of a fluid module, a sheath module and an ion Monte Carlo module, is employed to investigate the dependence of ion energy and angular distributions (IEDs and IADs) on the inductively coupled plasma (ICP) power, pressure, gas ratio, bias power and bias frequency in Ar/O 2 discharges. The results indicate that the bimodal distribution appears as bias power increases or bias frequency decreases. Moreover, the low and high energy peaks of IEDs move to higher energy with the rise of bias power and O 2 content. Whereas, an opposite tendency is observed with the increase of ICP power and pressure. For IADs, it is clear that a larger percentage of ions incident on the electrode have a smaller deflection angle by increasing bias power or decreasing pressure, and a similar evolution is observed with the decline of bias frequency. Besides, the better collimation of ions is obtained at larger O 2 concentration, but ICP power only has little influence on IADs. In order to validate the model, a comparison between the simulated IEDs and those measured by a retarding field energy analyzer has been done, and shows a good agreement. The results obtained in this work could help us to gain more insight into the dependence of IEDs and IADs on the discharge parameters, which is of significant importance in the improvement of the etching rate and anisotropy.

The time-resolved characteristics of pulsed inductively coupled O2/Ar plasmas have been investigated in this paper, by means of a Langmuir probe and a global model. The plasma properties, e.g., the electron density, effective electron temperature, and electron energy probability function (EEPF), have been experimentally investigated under various discharge conditions, combined with the comparison with simulated results. It is found that when the power is switched on, the electron density increases rapidly and then it reaches to a steady state with a constant value. When the power is switched off, the electron density exhibits a peak at the initial afterglow period, and then it decays gradually to a very low value. This peak may be caused by the detachment of negative ions. Moreover, it is noted that the effective electron temperature also increases to a peak value at the early afterglow, which can be understood by examining the evolution of EEPFs with time. Indeed, when the power is switched off, more moderate-energy electrons are produced through the collisions among the excited state particles and the energy loss of energetic electrons, and this is responsible for the peak of the effective electron temperature at the initial afterglow. In addition, the simulated results show a qualitative agreement with the experimental data, with the exception of the peaks in the electron density and effective electron temperature in the afterglow. The discrepancy in absolute values may be caused by the assumption of a Maxwellian electron energy distribution function distribution in the model.