SiH_4射频辉光放电等离子体特性的光发射研究

Study of properties of SiH4rf golw discharge plasma by optical emission spectroscopy

采用ＯＭＡ－４０００测量了ＳｉＨ_４射频辉光放电等离子体的光发射谱，研究了其谱线强度随放电射频功率和反应气体流量间的变化关系。结果表明：在放电射频功率增加和反应气体流量升高的过程中。其等离子体状态分别发生了性质不同的转变，这种转变联系到射频功率耗散机制的变化。当反应气体流量增加时，电子获得能量的机制由阴极暗区加速转变为等离子体内电场的加热效应；而在放电功率升高的过程中，离子轰击阴极产生的二次电子发射效应导致了光发射谱强度急剧增强的转变。

Optical emission spectra of SiH4 rf glow discharge were measured by OMA4000. Influence of rf power and reactive gas flow rate on the power of emissive . spectral lines was investigated. It has been found that different transitions related to the electrical power dissipation take place in the course of an increase in rf power and a rise in gas flow rate respectively. When gas flow rate increases to a certain value , the ' Joule heating ' mechanism by which electrons gain energy occurs in the plasma bulk. While rf power increases to a certain value , the secondary electrons generated from cathode by positive ions bombardment lead to the enhancement of plasma optical emission.