Effect of dust particle size on the plasma characteristics in a radio frequency capacitively coupled silane plasma

Abstract

Compared with dustfree plasmas, the existence of dust particles in plasmas may greatly influence the plasma properties, such as the plasma density, electron temperature, sheath properties, electron energy distribution function (EEDF) as well as the heating mechanism. In this work, a 1D hybrid fluid/MC model has been developed to investigate the interaction between dust and plasma in a lowpressure silane discharge sustained in a radio frequency capacitively coupled plasma, in which we assume spherical dust particles with a given radius are generated by taking the sum of the production rate of Si 2 H − 4 and Si 2 H − 5 as the nucleation rate. From our simulation, the plasma may experience definite perturbation by dust particles with a certain radius (more than 50 nm) with an increase in electron temperature first, which further induces a rapid rise in the positive and negative ion densities. Then, the densities begin to decline due to the gradual lack of sufficient seed electrons. In addition, as the dust radius increases, the high energy tails of the EEDFs will be enhanced for discharge maintenance, accompanied by a decline in the population of lowenergy electrons in comparison with those of pristine plasma. Furthermore, an obvious bulk heating is observed apart from the αmode and local field reversal heating. This may contribute to the enhanced bulk electric field (also called the drift field) as a result of electron depletion via the dust. In addition, largesized dust particles that accumulate near the sheaths tend to form two stable density peaks with their positions largely influenced by the timeaveraged sheath thickness. A detailed study of the effects of the external parameters, including pressure, voltage and frequency, on the spatial distribution of dust particles is also conducted.

Atmospheric pressure pulsed modulated arc discharge plasma

“…In the field of material preparation, Liu et al [28] introduced high-frequency RF into the preparation of thin film silicon, improving the efficiency of material preparation. In the field of RF mechanism, Krishnakum et al [29], Nienhius et al [30], Rehman et al [31], Yan et al [32], Kushner [33], Bruneau et al [34], Radouane et al [35], Jia et al [36] and others also deeply explored the electrical and product characteristics of high and low-frequency coupling, showing the feasibility of the sources modulating plasma electron temperature.…”

Three-dimensional simulation of laser-induced Mach cones in complex plasmas under microgravity conditions

“…组 [15] 和王友年研究组 [16] 采用流体尘埃模型建立 了尘埃颗粒在等离子体中的空间密度分布, 并采用 二维流体力学模型 [17][18][19] 研究了地面尘埃等离子 体中马赫锥产生的物理机理. 他们发现, 尘埃颗粒 马赫锥形貌的变化, 不仅能反映扰动声源的速度 大小, 还能说明等离子体性质的变化情况, 这里假 设尘埃等离子体为理想的单组分等离子体(onecomponent plasmas) [20,21] , 即只存在一种离子与均 匀分布的电子.…”