| The inductively coupled plasmas have been widely used in different material processes, such as the plasma etching and film deposition, since the high-density homogeneous plasma can be obtained under low-pressure discharges. For the planar-coil inductively coupled plasmas (TCP), this paper studies the characteristics of the radio-frequency ( rf) electric field and power absorption in the plasma.Firstly, assume the radius R of the discharge chamber is much larger than its height L, we then can use one-dimensional slab model to study the penetration behavior of the rf electric field in the plasma. Using the linear Boltzmann equation and Maxwell equations, and assuming that the electron energy distribution function (EDFF) obeys the Boltzmann distribution, we present general expressions of the rf electric field and power absorption, discuss the influence of the discharge pressure and electron temperature on these two quantities, and find the anomalous skin depth is about 2 cm. Next, we use further the the two-dimensional model to consider the radial changes of the rf electric field and the power absorption. Especially, we study the influence of the radial distribution of the coil positions on the rf electric field. Finally, we give a set of self-consistent equations to describe the interactions of the rf electric field with the plasma, namely, determine the EDFF and the rf electric field consistently.With the hydrodynamic model, this paper studies the effects of the charge-exchange collisions between ions and neutrals on the direct-current biased voltage sheaths. For the planar target, it is shown that the sheath thickness becomes small as the collisional parameter increases. A fitted expression of the Child-Langmuir law for the planar sheath is presented based on the numerical results. In addition, the influence of the target radius on the sheath thickness is also studied for the cylindrical and spherical targets, respectively.
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