| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of polishing a conductive film while precisely detecting a film thickness of from an extremely thin to a thicker conductive film formed on a semiconductor substrate. SOLUTION: By measuring an impedance of a reference wafer by an eddy current sensor 10, a relation among the impedance of the eddy current sensor 10, a frequency of an alternating current to be provided with a sensor coil, and a film thickness is calibrated. The eddy current sensor 10 supplies the sensor coil with the alternating current having a constant frequency to form the eddy current in a conductive film on a polish object, to measure the impedance including the conductive film seen from both terminals of the sensor coil, and to detect a change of the film thickness of the conductive film from the change of the impedance including the conductive film on the polish object. COPYRIGHT: (C)2008,JPO&INPIT
|
