| 摘要 |
PURPOSE:To accurately monitor the condition of etching such as the endpoint of etching and the like without having influence by the difference in etching conditions and the difference in the material to be etched by a method wherein the mutual induction between the material to be etched and a coil is utilized. CONSTITUTION:A coil 12 is arranged leaving the prescribed interval on the upper side or the back side of a wafer 2 having a metal film (conductive film) 1, a high frequency power is applied on the coil 12, the change in inductance of coil 12 is detected by a detecting part 13, and the etching condition is monitored. When a high frequency is applied to the coil 12, an induction current (eddy current) 15 runs on the metal film 1, and mutual induction is generated between the metal film 1 and the coil 12. The eddy current 15 runs heavily at the beginning of etching and while the etching is making progress, but said eddy current is reduced when the etching is approaching the endpoint because the metal film 1 becomes thinner there and there is a change in the resistance value. Thus, the progress of the etching can be monitored without utilizing a light. |
