电容耦合的抑制对感应耦合放电等离子体的影响

感应耦合等离子体(ICP)是微电子工业刻蚀高精度沟槽结构的首选高密度等离子体源.研究ICP的电特性与等离子体电学参量的变化显得非常重要.本文中,在平板型ICP源的感应线圈和介质窗口之间,使用了对称、均匀、呈辐射状的法拉第屏蔽板.结果表明,屏蔽板的使用不仅极大地降低了干扰等离子体参量测量的等离子体射频电位,而且也降低了线圈中的放电电流和等离子体中的轴向微分磁场信号强度,但Ar等离子体的发射光谱表明,法拉第屏蔽的采用对等离子体功率吸收的影响不大.对测量信号中出现的高次谐波行为也做了定性的讨论.

Influence of Suppression of Capacitive Coupling on Inductively Coupled Plasma

A novel technique to generate inductively coupled plasma(ICP) with high density has been successfully developed,in which a symmetrical,uniform and spoke-shaped Faraday shield is installed between the inductive coil and the dielectric window in the ICP source.The many strengths of the shield include considerable reduction of plasma rf potential,which strongly interferes plasma evaluation,decrease of discharge current of the coil,damping of the differential magnetic field signal,and negligible influence on the plasma power absorption as proved by argon optical spectroscopy.High order harmonic behavior in the measurement was also tentatively discussed.