| 摘要 |
PURPOSE:To prevent the generation of other impurity through reaction of internal wall of reaction tube with HF gas not changed to plasma by supplying inactive gas before supplying or after stopping supply of electrical energy for generating plasma. CONSTITUTION:A substrate 1 to be etched is placed on a holder and the substrate inserted to a quartz reaction furnace 2 is heated by a heater from the outside. Plasma is supplied by a high frequency power supply 13 in such a manner that an electrical energy is applied to a pair of mesh type electrodes 3, 3'. The reaction furnace opens respectively the valves 9, 10 with a vacuum pump 11 for the vacuum exhaustion. Thereafter, hydrogen is supplied from 6 and thereby internal pressure of reaction furnace is set to 0.05-3Torr. The valve 14 is then closed, the valve 8 is opened and the HF gas is supplied from 5. Thereafter, an output is applied from the high frequency power supply 13, plasma etching is carried out with the HF gas, the HF gas is stopped and the power supply (electrical energy supply source) is turned OFF. After the reaction tube is brought to the atmospheric condition with hydrogen, the substrate is taken out from the reaction furnace. |
