| 摘要 |
PURPOSE:To enable a parallel-plate-type plasma etching apparatus to effect high- quality etching treatment, by covering the surface of a substrate to be etched with a movable electrode having the same potential with a substrate supporting electrode for a period when plasma is still unstable after high-frequency power supply is initiated or interrupted. CONSTITUTION:A grounded anode 101 and a cathode 104 supporting a semiconductor substrate to be etched 103 are opposed to each other. A high-frequency voltage is applied to these electrodes 101 and 104 so that the surface of the substrate 103 is etched by using the plasma generated thereby. In this constitution, a movable electrode 102 having the same potential with the cathode 104 is further provided so as to be presented and retreated as required. While the plasma is still instable after the application of high-frequency voltage is initiated, the substrate 103 is covered with the movable electrode 102. After the plasma is stabilized, the electrode 102 is retreated so that the substrate 103 is subjected to plasma etching for a required period of time. This operation is performed if necessary also when the plasma is to be extinguished. |
