放电功率变化对电磁波在电感耦合闭式等离子体中的衰减特性

射频电感耦合等离子体(ICP)放电方式能够在较宽的压强范围内产生大面积、密度高的等离子体，在对电磁波衰减应用中具有较大优势。通过研究ICP等离子体与电磁波相互作用的过程，改进闭式等离子体模型，建立电磁波在非均匀等离子体中传播的分层计算模型，对实测诊断分布情形下等离子体与电磁波的相互作用进行研究，得到不同功率条件下电磁波衰减的变化情况；提出射频电感耦合闭式等离子体用于电磁波衰减的方法并实验验证，基于等离子体覆盖金属平板的测量模型，在实验室内搭建了以金属板为衬底的弓形微波反射测试系统，研究了闭式等离子体对4～8 GHz频段范围内微波反射的作用特性，以及不同射频功率对微波反射的影响规律，并将实验测量与计算结果进行对比分析。实验表明，通过功率调节，电感耦合闭式等离子体对5.92～6.8 GHz频带电磁波具有明显的衰减作用。

Attenuation characteristics of electromagnetic wave in inductive coupled plasma based on variation of discharge power

The application of Inductively Coupled Plasma (ICP) can cause a wide range high density plasma and has great advantages in electromagnetic wave attenuation. Studying the process of interaction between ICP and electromagnetic wave, we established the electromagnetic wave propagation in inhomogeneous plasma, adopted hierarchical model for the diagnosis of the interaction of plasma and electromagnetic wave, and studied the electromagnetic wave attenuation under different conditions of input power. The experiment method of inductively coupled plasma for attenuation electromagnetic wave was proposed. Based on the model of plasma covering over the metal plate, the arch system for measurement of microwave reflectivity of plasma was established. The interaction of closed-plasma and electromagnetic wave with a bandwidth of 4?8 GHz was studied, the effect on microwave reflection of different rf power was evaluated analyzed, and the experimental measurement and calculation results were analyzed. The experimental results show that the inductively coupled plasma attenuates the electromagnetic wave in 5.92?6.8 GHz band obviously by power regulation.