气体组分对大气压Ar/O_(2)/SiH_(4)放电影响的数值模拟研究

Numerical Simulation of the Effect of Gas Composition on Ar/O_(2)/SiH_(4) Discharge at Atmospheric Pressure

本文借助于二维流体力学模型对大气压下Ar/O_(2)/SiH_(4)放电进行了研究,重点关注了气体组分变化对前驱物粒子密度以及二氧化硅薄膜均匀性的影响。模拟结果表明:O_(2)含量在整个放电体系中起决定性作用。当SiH_(4)含量一定时,增加O_(2)含量可以在不改变电子密度的同时,较大程度提高薄膜的沉积速率、优化薄膜的均匀性。SiH_(4)含量主要对前驱物粒子SiH_(3)O密度有较大影响,对薄膜的贡献却很小。值得注意的是,当O_(2)含量与SiH_(4)相等时,SiH_(3)O粒子的生成通道占据主导地位,其密度较高;而当O_(2)含量大于SiH_(4)时,SiH_(2)O的生成通道会占据主导地位,其密度高于SiH_(3)O密度,同时SiO_(2)密度大幅提高,可以达到10^(17)cm^(-3)。因此在实际工业制备大面积薄膜的过程中,提高O_(2)含量有助于获得较高的沉积速率和高质量薄膜。

A two-dimensional fluid model is developed to study the radio-frequency atmospheric-pressure Ar/O_(2)/SiH_(4)discharges.The effect of gas composition on the densities of precursor particles and the uniformity of silicon dioxide film is emphasized.The simulation results show that the content of O_(2)plays a decisive role in the whole discharge system.When the content of SiH_(4)is constant,increasing the contents of O_(2)can greatly increases the deposition rate and optimizes the uniformity of the film without changing the electron density.Although SiH_(4)content significantly influencing the density of SiH_(3)O,it has little effect on the film properties.Note,when O_(2)content is equal to SiH_(4),the formation channel of SiH_(3)O particles is dominant and its density is high.When O_(2) content is greater than SiH_(4),SiH_(2)O generation channel will be dominate and its density is greater than that of SiH_(3)O.Meanwhile,the density of SiO_(2) increases greatly,and it can reach 10^(17) cm^(-3).Therefore,in the actual industrial preparation of largearea films,increasing the O_(2) content is helpful to obtain high deposition rate and high quality films.