| 摘要 |
PROBLEM TO BE SOLVED: To provide a film thickness measuring apparatus and a method that can significantly reduce the fluctuation range in the time axis direction and enhance the accuracy of measurement.SOLUTION: A film thickness measuring apparatus is equipped with a linear stage 18 that shifts a timing of arrival of probe light 4 at a detecting element 16 in an optical axis direction; a delay time detecting device 20 that detects a delay time of the probe light 4 due to the linear stage 18; an origin detecting device 30 that detects an origin of the linear stage 18; and a stage control device 40 that controls the delay time detecting device 20. The linear stage 18 is accelerated with the stage control device 40; and the delay time detecting device 20 detects, using as a trigger the point of time when the linear stage 18 took on a constant speed and passed the origin, the delay time of the probe light 4.SELECTED DRAWING: Figure 3 |
