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本文研究了在ＳＦ＿６、ＣＢｒＦ＿３和ＣＨＦ＿３与氧相混合的几种氟化气体等离子体中，ＳｉＣ薄膜反应离子刻蚀（ＲＩＥ）的深度。通过监测射频等离子体的光发射谱及产生等离子体的直流偏压来研究刻蚀机理。为了更精确地定量分析刻蚀工艺，使用氩光能测定技术使等离子发射强度转换为相应的等离子物质浓度。为获得选择性的ＳｉＣ－Ｓｉ刻蚀及ＳｉＣ薄膜的各向异性图形，对等离子体条件，如气体混合物的构成、压力和功率进行了研究。首次采用ＣＢｒＦ＿３／７５％Ｏ＿２和ＣＨＦ＿３／９０％Ｏ＿２，在等离子条件为２００Ｗ，２０ｓｃｃｍ，２０ｍｔｏｒｒ时，得到了ＳｉＣ：Ｓｉ的刻蚀速率的比值大于１。最好的各向异性截面是在ＲＩＥ方式下，采用ＣＨＦ＿３气体获得的。一个约－３００Ｖ的直流偏压临界值，对于ＳｉＣ刻蚀速率的限制区域分为化学和物理控制。对于所有气体，均在刻蚀后的ＳｉＣ膜上发现了富碳的表面。氟化气体中ＳｉＣ的刻蚀机理可从加载实验、表面分析及其他刻蚀现象中推断出来。文中给出了碳和氧之间发生化学反应的证据，而氟和碳之间发生化学反应的证据却没有观察到。通过实验，提出了一种化学和物理刻蚀相结合的模型。而为理解刻蚀截面，提出了碳保护的机理。
In this paper, the depth of reactive ion etching (RIE) of SiC thin films in several fluorinated gas plasma mixtures of SF_6, CBrF_3 and CHF_3 with oxygen was investigated. The etching mechanism was investigated by monitoring the optical emission spectrum of the radio frequency plasma and generating the DC bias of the plasma. In order to quantify the etching process more accurately, argon plasma energy measurement techniques are used to convert the plasma emission intensity to the corresponding plasma concentration. In order to obtain selective SiC-Si etching and anisotropic patterning of SiC thin films, plasma conditions such as composition, pressure and power of the gas mixture were studied. For the first time, CBrF 3/75% O 2 and CHF 3/90% O 2 were used. When the plasma conditions were 200W, 20sccm and 20mtorr, the etching rate of SiC: Si was higher than 1. The best anisotropic cross section is obtained using CHF_3 gas in the RIE mode. A DC bias threshold of about -300V limits the area of the SiC etch rate to chemical and physical control. For all gases, a carbon-rich surface was found on the etched SiC film. The etching mechanism of SiC in fluorinated gases can be inferred from loading experiments, surface analysis and other etching phenomena. The paper gives evidence of a chemical reaction between carbon and oxygen, with no evidence of a chemical reaction between fluorine and carbon. Through experiments, a model combining chemical and physical etching is proposed. In order to understand the etching cross section, the mechanism of carbon protection was proposed.