低气压射频感性耦合cf4和chf3放电的流体模拟研究-等离子体物理专业毕业论文.docx

射频感性耦合CF4和CHF3放电的流体模拟研究
Fluid simulation of Inductively Coupled CF4 and CHF3 Discharge at
Low—pressure Abstract
Radio Frequency inductively coupled plasma(RF—ICP)is widely used in the fields of semiconductor fabrication and material surface treatment due to its advantages of easily producing large area,uniform,high plasma at low pressure,its simple equipment and easily adjustable working practice,the plasma state is determined by external factors, such as parameters ofplasma sources,properties ofworking gas,and chamber geometry. Because ofthe high etching rate,the high selectivity and anisotropy etc.,fluorocarbon gas has been widely used in micro-electronics fabrication.
A fluid modeliS used to investigate the discharge of CF4 and CHF3 in
an ICP chamber respectively aiming to acquire the spatial distribution of the particle density and the electron temperature,further analyze the physical mechanism of the two kinds of gas the interaction process within the study objects,fluid model is used to calculate the CF4 and CHF3 gas due to its puting simulating
general rules of CF4 and CHF3 discharge are acquired under certain discharge condition using fluid maximum values of electron density and F—density appear in the center of the discharge chamber in CF4,while in CHF3 the maximum values of electron density and F。
density deviate from the discharge maximum value of electron temperature
appears below the coils in both two gases and the electronegativity of CHF3 is less than CF4. The article also analyzes the variation trend of electron density,F’density and electron
temperature with power and pressure in the two is found that the electron density and
electron temperature both increase with power in the two gases,but the change rule of F—S
density iS the CF4 discharge,the density of F—increases first and then decreases in the center of the chamber with