| 摘要 |
PURPOSE:To enable efficient formation of a diamond film having high purity, by passing a raw material gas through an arc discharge column and introducing the produced gas plasma to a substrate to form a diamond film on the substrate. CONSTITUTION:An arc discharge column is formed between a pair of oppositely placed electrodes and a raw material gas is passed through the arc discharge column to form a gas plasma. The gas plasma is introduced to a substrate placed near the arc discharge column to effect the deposition of a diamond film on the substrate. There is no temperature restriction in the present process in contrast to a hot filament process in which the temperature is limited to about 2,000 deg.C and, accordingly, the raw material gas can be decomposed in remarkably high efficiency by the present process. For example, the dissociation ratio of hydrogen is less than several % at 2,000 deg.C whereas dissociation ratio of as high as 70-80% can be expected at 4,000 deg.C. Accordingly, a high-speed growth of diamond film can be anticipated. The process is extremely inexpensive because an accelerator, etc., is unnecessary in contrast to a conventional ion beam process. |
