微波干涉仪设计与射频等离子体诊断

发布时间：2018-02-03 02:26

本文关键词： 干涉仪电子密度诊断电容耦合等离子体　出处：《中国科学技术大学》2017年硕士论文　论文类型：学位论文

【摘要】：等离子体是一个复杂的多参量体系,对电子密度,电子温度、活性粒子密度、电子能量分布等参量进行诊断,是低温等离子体研究的重要工作。在等离子体诊断技术中,利用微波和等离子体相互作用的等离子体参数诊断技术具有无扰动、时间分辨率高等特点;不同的相互作用机制发展出了多样化的微波诊断方法,其在等离子体特性研究中发挥着越来越重要的作用。本文设计构建了零拍微波干涉仪诊断系统,并用其对电容耦合等离子体密度进行了测量,对干涉仪系统的性能进行了分析。利用质量能量分析仪对氢气等离子体离子特征进行了诊断,研究了氢气分子束流引入对ECR氢等离子体中离子特征的影响。根据待测等离子体的密度范围及尺寸,我们选用10 GHz的微波作为干涉仪系统的工作频率,并根据系统中各部分功率的损耗,确定出我们所选择的干涉仪器件,系统使用聚焦喇叭天线发射和接收微波。利用所搭建干涉仪对氩气等离子体密度测量,实验中测量结果显示干涉仪相位噪声标准差为0.057度,对应的弦平均电子密度误差为3.37×107cm~(-3)。利用脉冲调制的400kHz射频放电,在放电功率80 W、气压100 Pa和占空比50%条件下,测量的氩气等离子体密度为5.9×109cm~(-3),等离子体达到最大密度需要的时间为2.5ms,而功率上升沿的时间为3 μs,利用质量能量分析仪对等离子体的离子种类和离子能量进行了研究,在电子回旋共振氢气放电中,探测到了 H+、H2+和H3+三种离子,其中以H2+离子为主,离子密度和离子平均能量都随输入功率的增加而增加,实验发现在等离子体下游引入氢气束流会导致离子通量迅速减少,而离子的平均能量增加。探测到的三种离子的相对含量也随引入束流的增大而变化。
[Abstract]:Plasma is a complex multi-parameter system. The parameters such as electron density, electron temperature, active particle density and electron energy distribution are diagnosed. It is an important work in the research of low temperature plasma. In the plasma diagnosis technology, the plasma parameter diagnosis technology using the interaction of microwave and plasma has the characteristics of no disturbance, high time resolution and so on. Different interaction mechanisms have developed a variety of microwave diagnostic methods, which play an increasingly important role in the study of plasma characteristics. In this paper, a zero-beat microwave interferometer diagnosis system is designed and constructed. The density of capacitance-coupled plasma is measured, the performance of interferometer system is analyzed, and the ion characteristics of hydrogen plasma are diagnosed by using mass and energy analyzer. The influence of the introduction of hydrogen molecular beam on the ion characteristics in ECR hydrogen plasma was studied. The density range and size of the plasma to be measured were studied. We choose the microwave of 10 GHz as the operating frequency of the interferometer system, and according to the power loss of each part of the system, we select the interferometer device. The focused horn antenna is used to transmit and receive microwave, and the interferometer is used to measure the density of argon plasma. The experimental results show that the standard deviation of phase noise of interferometer is 0.057 degrees. The corresponding average electron density error is 3.37 脳 10 ~ 7 cm ~ (-1) ~ (-1) ~ (-1). The pulse modulated 400kHz RF discharge is carried out at a discharge power of 80 W. The measured argon plasma density is 5.9 脳 10 ~ 9 cm ~ (-1) ~ (-1) C ~ (-3) at 100 Pa and duty cycle 50%, and the time required for the plasma to reach the maximum density is 2.5 Ms. The time of power rise was 3 渭 s. The ion species and ion energy of plasma were studied by mass energy analyzer. The H was detected in the electron cyclotron resonance hydrogen discharge. The ion density and average energy of H _ 2 and H _ 3 increase with the increase of input power. It is found that the introduction of hydrogen beam downstream of the plasma leads to a rapid decrease in ion flux and an increase in the average energy of ions, and the relative contents of the detected three ions vary with the increase of the introduced beam current.
【学位授予单位】：中国科学技术大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O536;TH744.3

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