射频辉光放电CH4等离子体中电子的能量分布

通过求解Lorentz简化的玻尔兹曼方程,得到射频放电CH₄等离子体中电子的能量分布函数.求解过程中使用一个简化的射频电场模型代替泊松方程求解放电电场.共计包含6类环境气体及27种电子碰撞反应.通过EEDF对等离子体中的电子反应率系数、电子平均能量、电子的传输率系数等进行求解分析.结果表明,在等离子体鞘层区域电子能量具有Maxwell分布形式,在正柱区域具有Druyvesteyn分布形式.最高电子能量和最大反应率系数出现在鞘层区域.电子的迁移率系数和扩散率系数随射频周期的演化时空分布不均匀.

Electron Energy Distribution in Radio-frequency CH_4 Plasma

Electron energy distribution function(EEDF) in RF methane plasma is calculated with Boltzmann equation and Lorentz approximation. Instead of a self-consistent RF field satisfying Poisson's equation,a simple electric field distribution is used.6 neutrals are included,as well as 27 electron-neutral reactions.EEDF yields information about electron reaction rates in plasma,electron average energy,and transport coefficients.In the sheath region,EEDF is Maxwellian,and in the bulk region a Druyvesteyn EEDF is found.An electron average energy peak occurs in the sheath region,together with electron reaction rates.Differing from constant transport coefficients used in references,electron diffusion and mobility coefficients strongly depend on RF period and space.