A Numerical Study on Tuned Substrate Self-Bias in a Radio-Frequency Inductively Coupled Plasma

作者：CHEN Longwei DING Zhenfeng WANG Younian State Key Laboratory of Materials Modification by Beams Dalian University of Technology Dalian China

来源：Plasma Science and Technology, 2006, (04): 409-415.

• Rf plasma
• equivalent circuit
• capacitive coupling
• mode transition

<正> The tuned substrate self-bias in a radio-frequency inductively coupled plasma iscontrolled by varying the impedance of an external tuning LCR (inductor,capacitor and resistor)network inserted between the substrate and the ground.In experiments,it was found that thevariation of the tuned substrate self-bias with the tuning capacitance demonstrated three features,namely,continuity,instability and bistability.In this paper,a numerical study is focused onthe elucidation of the physical mechanisms underlying continuity and bistability.For the sake ofsimplicity and feasibility to include the key factors influencing the tuned substrate bias,the tediouscalculation of inductive-coupling to obtain the plasma density and electron temperature is omitted,and discussion of the tuned substrate self-bias is made under the prescribed plasma density andelectron temperature.On the other hand,the parameters influencing capacitive-coupling areretained in modeling the system with an equivalent circuit.It is found that multi-stable stateappears when one of the parameters,such as the resistance in LCR,substrate area and plasmadensity,decreased to its critical value,or the rf voltage or electron temperature increased to thecritical value individually.In the reverse cases,the tuned substrate self-bias varies continuouslywith the tuning capacitance.

• 出版日期2006-7-15