J.A. Woollam M-2000, Руководство по оборудованию

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M-2000® Hardware Manual ©2023 J.A. Woollam Co. 155
Successful calibration wafer and straight-through measurement is a strong
indicator that the tool is working properly. If the measurement is not successful,
a System Check should be performed.
11.2 System Check
A System Check is another easy way to verify that the instrument is operating
properly. A System Check can be performed instead of simply measuring the
calibration wafer. A System Check should be performed if the calibration wafer
or straight-through measurement is unsuccessful.
A System Check executes a quick calibration of the ellipsometer optics and
measurement of the calibration wafer. The System Check procedure, and
discussion for successful vs. unsuccessful System Check, is described in Section
4.9 of this manual.
Successful System Check is a strong indicator that the tool is working properly.
11.3 Verify Sample Alignment
Proper operation of the instrument relies on proper sample alignment. If the
sample is misaligned, measured data (and results) will not be accurate. The
Sample Alignment must be performed for each sample that is mounted on the
ellipsometer, prior to acquiring data.
Successful Sample Alignment requires that the following conditions are
simultaneously satisfied (see Chapter 4 for complete details):

The tip/tilt of the sample should be aligned such that the sample surface
is perpendicular to the plane defined by the optical axes of the source
and receiver; alignment screen cross hair should be centered.

The Z height of the sample should be aligned such that the Receiver Unit
is collecting the reflected beam; the beam is centered on the Receiver
aperture and intensity is maximized.

Alignment should be maintained with angle change (the cross hair should
not move more than 15 units in X or Y on the Receiver unit Detector).
Note: Reflected intensity is a function of angle; therefore, the intensity
will change as angle changes, but the reflected beam should remain
centered on Receiver Aperture for all angles.
If these conditions cannot be simultaneously satisfied, the System Alignment
should be verified.