电子回旋共振放电中电子能量分布特性的研究

Research on Electron Energy Distribution Features in Electron Cyclotron Resonance Discharge

建立了电子回旋共振(ECR)放电的粒子模型,编制了准三维电磁模粒子模拟与蒙特卡罗模拟程序。通过对氩气ECR放电电离过程的理论分析与数值模拟,得到了放电稳态形成时不同放电区域的电子能量分布。研究了不同中性气压以及外加磁场位形对这些区域中电子能量分布特性的影响。随着中性气压的升高,远离ECR区域中的低能电子减少,高能电子增加,而ECR区域中电子能量分布变化特征与之相反;相对于收敛磁场位形,磁镜磁场位形更有利于约束放电下游区的电子能量以及电子能量分布的宽度。

The code with quasi-three-dimensional electromagnetic particle-in-cell plus Monte Carlo collision （PIC/MCC） method is proposed for the research of ionization process of argon electron cyclotron resonance （ECR） discharge. The electron energy distributions in different regions of ECR reactor are obtained when the steady state of ECR discharge attains, and the variations of these distributions with neutral pressure and external magnetic field are also discussed. As the neutral pressure increases, the low energy electrons decrease and the high energy ones increase at the region away from ECR layer, while the variations of electron energy distribution with neutral pressure are opposite at ECR layer. In the far downstream region, the electron energy confinements are better with the mirror-type magnetic configuration than with the convergence-type one. The simulation results and discussions are useful for the optimization of the ECR plasma applied in deposition, etching or other micro-electronic fabrications.