【作者】 刘晓华；

【导师】 王友年；

【作者基本信息】 大连理工大学 ， 等离子体物理， 2012， 硕士

【摘要】 脉冲调制感性耦合等离子体(Pulse-modulated inductively coupled plasma)源是在感性耦合等离子体(Inductively coupled plasma,简称ICP)源的基础上提出的,区别在于对ICP源的射频功率源进行了脉冲调制,即脉冲调制作用相当于射频功率源的一个自动开关,射频源的功率周期性的输入激发等离子体的产生。脉冲调制ICP源仍具有ICP源的优点,如等离子体密度高(1011-1012cm-3)、工作气压低(1-100mTorr)和等离子体源的装置结构简单等优点。之所以提出脉冲调制ICP源,是因为随着微电子工业中加工的Si基片尺寸的增大和刻蚀槽宽的减小,ICP源呈现出一些缺点和不足,如基片表面积累的电荷引起基片损伤和旁刻等现象。脉冲调制ICP源能够很好的解决这些问题,而且脉冲调制ICP源较传统的ICP源多两个控制参数(脉冲重复频率和脉冲占空比),对优化等离子体工艺参数有帮助,所以研究脉冲调制ICP的物理特性很有意义。因此,本文的研究目的是：基于本实验室的平面线圈感性耦合等离子体源设备,使用光探针对脉冲调制ICP源的发光强度随实验参数的变化进行了研究,从而分析了实验参数对等离子体发光强度的影响。论文的第一章首先综述了低温等离子体源的分类及相应特性,其中特别详细描述了ICP源的激发原理及脉冲调制作用对ICP源的影响；其次介绍了低温等离子体研究中常用的几种诊断方法；之后系统的总结了前人对脉冲调制ICP源的实验研究进展,并指出对脉冲调制ICP源的研究过程中存在的问题；最后是本文的结构安排和研究计划。第二章详细的介绍了本实验所使用的脉冲调制ICP源和使用的诊断仪器光探针。第三章、第四章、第五章是使用光探针分别对Ar、02、Ar/O2的脉冲调制射频感性耦合等离子体放电特性进行实验研究的结果。结果显示：在Ar的脉冲调制ICP放电中,Ar的750.4nm和811.5nm谱线强度随着功率、脉冲占空比的增加而单调的增加,然而随着脉冲重复频率变化不明显。在02的脉冲调制ICP放电中,O原子的777.4nm和844.6nm谱线强度随着功率、脉冲占空比的增加而单调的增加,然而随着脉冲重复频率变化不明显。在Ar/02的脉冲调制感性耦合等离子体放电实验中,Ar的750.4nm和811.5nm谱线强度与O原子的777.4nm和844.6nm谱线强度随着02含量的增加先增加后下降,随着功率、脉冲占空比的增加而单调的增加,然而随着脉冲重复频率变化不明显。此外,将脉冲调制射频感性放电与射频感性放电的等离子体的参数进行了比较,结果显示,脉冲调制后的等离子体参数的时间平均值的变化规律与射频感性放电的变化规律一致。更多还原

【Abstract】 Pulse-modulated inductively coupled plasma (pulse-modulated ICP) source is based on inductively coupled plasma (ICP). The difference is that the radio-frequency (RF) power source of ICP source is pulse-modulated. That is to say, pulse-modulated acts as an automatic switch of the RF power source. The power of the RF source input periodically to stimulate the plasma generation. Pulse-modulated ICP source still has the advantages of the ICP source, such as high plasma density, low pressure and simple device structure. With the increasing of the size of Si substrate, the ICP source presents some shortcomings, such as substrate damage, charge accumulation on the substrate. Pulse-modulated ICP can solve these problems well. So the study of pulse-modulated ICP is meaningful.Therefore, the purpose of this study is to research the characteristic spectrum line intensity of the pulse-modulated ICP with changes in experimental parameters by using the optical probe on the planar coil inductively coupled plasma source device, so as to analyze the impact of experimental parameters on the intensity of emission spectrum.The first chapter of the thesis reviews the classification of the low-temperature plasma sources and the corresponding features. In particular, a detailed description of the ICP excitation principle and the impact of pulse-modulated on the ICP are introduced. Secondly, it introduces several commonly used diagnostic methods in the study of low-temperature plasma. Third, I summarize previous study on the pulse-modulated ICP. Finally, the structural of the thesis is characterized.In Chapter2, the pulse-modulated ICP source used in this study and the diagnostic instruments devices are described in detail.In Chapter3to5, the results of the experimental study of pulse-modulated ICP Ar, O2, Ar/O2discharge are described respectively by using optical probes. The results showed that, in the pulse-modulated ICP Ar and O2discharge, the characteristic spectrum line intensity of Ar and O2increase monotonically with pulse duty ratio, power. With the increasing of pulse repeated frequency, there is no obvious change of the spectrum intensity. In the Ar/O2pulse-modulated inductively coupled plasma, we use optical probe to diagnose the spectrum intensify of Ar and O atom. The spectrum intensify of Ar at750.4nm and811.5nm has been obtained versus the content of O2, the applied RF power, pulse duty ratio, pulsed repeated frequency, pressure and the position of radial. The same measurement has been taken for O atom spectrum at777.4nm and844.6nm. The results show that the spectrum intensity of Ar and O atom increase firstly with the increasing of O2content and decrease later, and the spectrum intensity of Ar and O atom increases monotonically against the input power, and the duty ratio. The change of the spectrum intensity of Ar and O atom is not obvious with the pulsed repeated frequency. In addition, under the same conditions, there is a comparison between inductively coupled plasma and pulse-modulated inductively coupled plasma. The result shows that the time-averaged spectrum intensity of pulse-modulated inductively coupled plasma is lower than inductively coupled plasma.更多还原