硅烷低温等离子体阶跃响应的仿真(1)

Simulation of step response of silane low-temperature pasma(1)

了解含有负离子的低温等离子体的过渡特性,在等离子体控制过程中,尤其在选择性等离子体腐蚀工艺和改善电荷堆积等现象中是十分重要的课题.对电源驱动频率为13.56MHz,压力为0.5Torr(0.5×103.33Pa)状态下的硅烷(SiH4)低温等离子体的阶跃响应进行仿真.当电源电压振幅从550V阶跃减小到350V时,硅烷低温等离子体表现出以数千RF周期为周期的振荡现象,等离子体中的带电粒子的运动变化决定了振荡现象的产生和振荡周期等特性.

Understanding of the transient response of electronegative radio-frequency glow plasmas is important for process control, better selectivity etch technology and charge free etching. We have investigated the step responses of RF(l3.56 MHz) silane gas plasmas at a pressure of 0.5 Torr (0.5 × 103.33Pa). The result showed that, when the power voltage changed stepwise from 550 V to 350 V, a steady state pulsed plasma oscillation at a few kHz appeared. The transient behavior and oscillation were interpreted in terms of the transport and chemistry of charge carriers in the plasma.