Production of a Large Diameter Plasma with a Lisitano Coil

利用里西塔诺线圈产生了大直径ECR等离子体，并从实验和理论上研究了产生等离子体的机理。利用里西塔诺线圈进行了等离子体化学气相沉积实验。主要研究结果如下。1.通过测量带有小天线的里西塔诺线圈辐射的电磁场分布，阐明了大直径ECR等离子体的产生机理。2.通过控制ECR点，即使用一个小的里西塔诺线圈(直径9 cm)也可以实现直径为45 cm的均匀等离子体。3.ECR等离子体通常在相对较低的压力下使用。然而，对于等离子体CVD来说，在高压下产生等离子体是必要的。通过增加微波功率，我们成功地产生了20mTorr的ECR等离子体。4.用H_2-CH_4混合气体在5英寸硅片上进行ECR等离子体化学气相沉积，在硅片上形成了均匀的碳膜。研究了沉积速率与气压、气体混合速率和衬底温度的关系，得出了里西塔诺线圈适合于ECR等离子体CVD的结论。此外，本实验所获得的结果将有助于对大直径薄膜的要求，这是等离子体加工等工业应用中最重要的课题之一。

A large diameter ECR plasma is produced with a Lisitano coil and the mechanism of the plasma production is studied experimentally and theoretically. The experiments on plasma CVD using the Lisitano coil are also performed. The main results are as follows. 1. The mechanism of the production of a large diameter ECR plasma is clarified by measuring electromagnetic fields distributions radiated from the Lisitano coil with small antennas. 2. A 45 cm-diameter uniform plasma is realized by controlling ECR points even with a small Lisitano coil (diameter 9 cm). 3. An ECR plasma is usually used at relatively low pressures. It is necessary for plasma CVD, however, to produce the plasma at high pressures. We succeed in producing an ECR plasma at 20 mTorr by increasing the microwave power. 4. Uniform carbon films are formed on 5 inch silicon wafers by the ECR plasma CVD using H_2-CH_4 gas mixture. The deposition rate is examined as a function of pressure, gas mixing rate, and substrate temperature.It is concluded from these results that a Lisitano coil is suitable for the ECR plasma CVD. Moreover, the results obtained in this experiment will be useful for the requirement of larger diameters of thin films, which is one of the most important subjects in such an industrial application as plasma processing.