碰撞辐射模型诊断大气压双频氩等离子体电子密度和电子温度的二维分布

Diagnosis of two-dimensional distribution of electron density and electron temperature in atmospheric pressure dual frequency argon plasma using collision radiation model

利用发射光谱结合碰撞辐射模型(OES-CRM),探究大气压双频(2.00 MHz、13.56 MHz)等离子体的放电特性。使用CCD相机结合带通滤波片拍摄特定波长(694.3 nm、750.0 nm)谱线强度的二维图像,通过碰撞辐射模型计算等离子体电子密度和电子温度的轴向分布和二维空间分布。试验中,分别改变低频电源和高频电源的功率,探究高频分量和低频分量对放电的影响。结果表明:随着高频功率的增加,电子密度明显增加,且体区两端靠近鞘层处变化更明显,而电子温度略有升高;增加低频分量时,放电强度降低,等离子体的电子密度和电子温度均略有降低,等离子体鞘层明显向体区扩张。总体上,高频分量主要影响电子温度和电子密度的量,而低频分量主要影响电子温度和电子密度的空间分布。可见大气压双频放电能独立调控等离子体的参数值和空间分布,具有重要研究意义。

The discharge characteristics of atmospheric pressure dual frequency(2.00 MHz,13.56 MHz)plasma were investigated by emission spectroscopy combined with collision radiation model(OES-CRM).A CCD camera combined with bandpass filters of specific wavelengths(694.3 nm,750.0 nm)was used to capture two-dimensional images of specific wavelength spectral line intensities,and the axial and two-dimensional spatial distributions of electron density and temperature were calculated.The power of low-frequency generator and high-frequency generator were changed respectively,and the influence of high-frequency and low-frequency components on discharge was explored.The results show that with the increase of high-frequency power,the electron density significantly increase,and the changes near the sheath are more significant than the bulk region,the electronic temperature has increased slightly.By increasing the low-frequency power,the discharge intensity decreases,and the electron density and temperature of the plasma slightly decrease,the plasma sheath expands towards the bulk region.In general,the high-frequency component mainly affects the electron density and electron temperature,while the low-frequency component mainly affects the spatial distribution of discharge parameters.Therefore,the dual frequency discharge at atmospheric pressure has the characteristics of independent regulation of parameters and spatial distribution of plasma,which has important research significance.