Effect of antenna configuration on power transfer efficiency for planar inductively coupled plasmas
平板型感应耦合等离子体源的线圈配置对功率耦合效率的影响

Based on a transformer model for inductively cowpled plasmas (ICPs), the dependence of power coupling efficiency on Q value, plasma electron density and effective electron_atom collision frequency is analyzed. The effect of coil configuration on power coupling efficiency is studied using four types of coils (one_turn, two_turn, three_turn and four_turn planar concentric coils) experimentally. The results indicate that the inductive discharge depends on coil inductance while the coupling efficiency varies with the Q value and discharge conditions such as pressure and input power. The coupling efficiency increases with the increase of pressure and input power, which is in accordance with the transformer model. However, the prediction given in the model that an increase in coil Q value improves power coupling efficiency is only applicable for coils with the same inductance. The study on power coupling efficiency for single multi_turn coil has been applied as an experimental reference for a large_area, high density inductive discharge source using four parallel multi_turn coils.