| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an eddy current sensor capable of detecting a metal thin film (or a conductive thin film) on a substrate such as a semiconductor wafer without increasing an oscillation frequency, the amplification degree of an internal circuit, and an exciting voltage, in the eddy current sensor. <P>SOLUTION: In the eddy current sensor provided with a sensor coil 60 disposed in the vicinity of the substrate on which a metal film (or a conductive film) mf is formed, the sensor coil 60 has an oscillation coil 62 connected to a signal source, a detection coil 63 detecting an eddy current formed in the metal film or conductive film mf, and a balance coil 64 connected to the detection coil 63 in series, and the detection coil 63 comprises a coil formed by winding a wire rod or a conductive body by a single row and multiple layers, when the row is defined as a direction perpendicular to the substrate and the layer is defined as a direction parallel to the substrate. <P>COPYRIGHT: (C)2012,JPO&INPIT |
