| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for evaluating a minute measurement positional deviation of a thickness measuring device for wafer, and a thickness measurement method improving an accuracy of position in thickness measurement.SOLUTION: The method includes: a step S1 of preparing an epitaxial wafer having an outer peripheral film thickness distribution of 0.1% or less and a thickness of 0.3 μm or more, preferably 1 μm or more and 100 μm or less; a step S2 of installing the epitaxial wafer into a measuring device so that a notch thereof is located in a 12 o'clock-direction (normal installation), and measuring two thicknesses in 0°- and 90°-directions with the notch as 0°; a step S3 of rotating the epitaxial wafer by 180° from the position when normally installed, installing the wafer into the measuring device (reverse installation), and measuring the thicknesses of the wafer at the same measurement points as the normal installation; a step S4 of acquiring a difference between the obtained thicknesses at the same measurement point; a step S5 of evaluating a measurement positional deviation on the basis of the difference; a step S6 of correcting the measurement position of the measuring device on the basis of the evaluation result; and a step S7 of thereafter performing thickness measurement of the wafer using the corrected measuring device.SELECTED DRAWING: Figure 2 |
