| Low-temperature plasma technology has been widely applied in many science fields, such as microelectronics, materials science, chemical engineering, mechanical engineering and environmental protection. With the continual research in the operation process of low temperature plasma and the interaction mechanism between plasma and material surface, low temperature plasma technology develops rapidly and applies in many new industry productions.Particle-in-cell (PIC) and Monte-Carlo collision (MCC) simulation method could track the movement of large numbers of charged particles using computers, and macroscopical physical property or physical laws could be gained by statistical calculation with these micro particles. PIC method could show the practice plasma laws of the moving charged particles, for the basic movements of plasma particles were involved in its simulation. To some extent, PIC simulation method could replace the experimentation in plasma research. Now PIC method becomes a powerful simulation tool especially applied in plasma research.This paper simulated some plasma application technologies using PIC method:(1) The simulation of the discharge cell of plasma display panel (PDP):In plasma display panel, the discharge cell is the basic structure element. There are some new cell structures developed in recent years. For example, WAFFLE structured rib is one of the new cell structures, which divides the whole PDP panel into numerous individual closed discharge cells. Some experiments have proved that this new structure could improve the luminous efficiency and prevent light leakage into the neighboring discharge cells.The first part of this paper contains the simulation research of new WAFFLE type discharge cell in Alternating Current PDP (AC-PDP). Using 2D PIC-MCC method, the spatial distribution of potential, charged particles density, the energy distribution of incident ions and the incident angle distribution of ions in this close discharge cell could be recorded. The simulation results show that the introduction of dielectric side barrier in WAFFLE type discharge cell could not affect the discharge property in the cell. To a certain extent, the dielectric side barrier could reduce the collision probability between the energetic ions and the dielectric protection layer. Thus the usage of dielectric barrier could prolong the lifetime of the protection layer and discharge cell in PDP, also it indirectly improves the lifetime of PDP.This paper also used 2D PIC-MCC method to study the striation phenomenonoccurring with the discharge in the WAFFLE cell of AC-PDP. Considering the effect of the width of dielectric side barrier and optimizing the discharge parameters, the obvious plasma striation phenomenon could be seen during the simulation process. The simulation results show that the striation phenomenon only occurred on the anode region, and the introduction of dielectric barrier could weaken the striation phenomenon in the WAFFLE type discharge cell. The formation of the striations was affected by the combination effect with the distribution of spatial potential and surface charge on the anode surface, especially the distribution of electron charge on the anode surface would greatly influence the structure of striations. The variety of the potential distribution in the cell would directly affect the distribution of the charged particles, and the fluctuation of the spatial potential makes the fluctuating of the density distribution of plasma particles.(2) The simulation of radio frequency (RF) capacitive coupled plasma (CCP):RF CCP has many industry applications, such as plasma thin-film deposition, plasma etching, and plasma cleaning. Especially in micro-electronic industry and semiconductor industry production, CCP has been widely used in plasma etching for ultra micro scale. In conventional single frequency (SF) CCP reactor, plasma density and ion energy could not be well controlled independently, and the efficiency of discharge also could not be improved. Now dual frequency (DF) CCP becomes a new research focus, which could control the distribution of ion energy and gain higher plasma density using two RF sources.Using 1D PIC-MCC method, the second part of this paper studied the plasma density, the distribution of ion energy during the discharge of SF CCP reactor and DF CCP reactor. It could be found that, in DF CCP, with the increasing of low-frequency voltage, the plasma density would decrease and the width of plasma sheath would become wider, and the range of ion energy would also become broader. But with the increasing of high-frequency voltage, the plasma density would increase and the width of plasma sheath would become decreasing. Comparing with the effect of two RF sources in DF CCP, the high-frequency source could be used to control the plasma density of the discharge, while the low-frequency source could be used to control the sheath width and ion energy.(3) The simulation of plasma immersion ion implantation (PIII):Plasma immersion ion implantation is a new technology, which is widely used for modifying the surface property of many materials. During the process of surfaceproperty modification, the dose distribution of ion implantation in the target surface is an important parameter to verify the success of modification. To predict the ion implantation dose in the treating apparatus surface would help people improve the efficiency of PIII.A 2D PIC model was used to simulate the PIII process for a planar target. The simulation results in one whole pulse show that the sheath expands with a decreasing speed and the sheath shape would change form elliptically cylindrical to circularly cylindrical. The dose distribution of ion implantation in the target surface is not uniform, and the concentration depth profiles of retained dose are considerably different, in different positions of the target.(4) The simulation of magnetron sputtering plasma:Magnetron sputtering plasma is one of the main methods to produce the thin film in microelectronics industry. As the microelectronics industry grows exponentially, the fabrication of thin film process becomes an important point, and many researchers focus on it. The simulation studies on the magnetron sputter could help to optimize the real technology of magnetron sputtering.A 2D PIC-MCC model was used to simulate the plasma generation of magnetron sputter, and a MC method was used to simulation the macrofilm deposition.The simulation results of plasma generation show that: the density distribution of charged particles is affected by the distribution of magnetic field; the magnetic field also affects the energy distribution and angle distribution of Ar ion; and the ion flux of the target surface has two peaks.The simulation results of macrofilm deposition show that: the ion flux directly affects the sputtering rate of ions; the curve of sputtering rate presents two peaks, where the ion flux curve also has the same peak. The operation gas pressure and the TS(Target-Substrate) distance would greatly affect the deposition uniformity of film: when process pressure increasing, the deposition rate decreases and deposition uniformity is enhanced; and as the TS distance decreasing, the deposition uniformity is weakened.
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