Patent attributes
A method for forecasting a polishing end time or point, wherein an inductor 36 in a sensor is placed adjacent to the conductive film 28. The magnetic flux formed by the inductor 36 is monitored, and a change of magnetic flux induced in the conductive film 28 is detected. Based on the skin effect of the material of the conductive film 28 as a factor, a process is used in which an eddy current formed with the decrease of the film thickness by polishing increases and a process in which the eddy current formed with the decrease of the film thickness substantially decreases when the polishing is progressed. Based on the characteristic change of the magnetic flux induced in the conductive film 28, the polishing end point is forecasted, and at the same time, the magnetic flux induced in the conductive film 28 is alleviated or turned off.
