Polytec MSA-600, Operating Instructions Manual

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6-12
6 Technical Specifications
6.7.2 Topography Measurements
INFORMATION
The values given apply to a measurement with a 10x objective with a
scanning rate of 3.36 µm/s. This corresponds to a sampling interval of 80 nm.
Surface
Smooth
1
(Phase
evaluation)
Rough
2
(Envelope
evaluation)
Z performance:
Measurement noise (N = 25) (measurement
noise of an averaged measurement)
3
0.09 nm 6 nm
Average measurement noise (stabilized
measurement noise)
4
0.35 nm 16 nm
Vertical resolution
5 < 1 nm < 37 nm
Flatness measurement:
Average flatness deviation
(stabilized flatness deviation)
6
4.5 nm 45 nm
Repeatability (N = 50)
7 0.25 nm 14 nm
1
Analysis of the correlogram phase, can be used on flat surfaces.
2
analysis of the correlogram envelope, for usage on unsteady/rough surfaces.
3
RMS value of the signal amplitude for an averaged measurement on a parallelly aligned plane mirror (R
≈
4%,
λ
/20),
calculated from 25 single measurements, under repeatability conditions. The averaged data was post-processed as follows:
Alignment, 5 x 5 median filter with threshold 3 nm (phase evaluation)/40 nm (envelope evaluation), high pass filter
λ
c = 0.25 mm. The reference file has also been created from an averaging of 25 measurements.
4
Averaged RMS value of the signal amplitude of 49 differential topographies calculated from 50 subsequent measurements on
a parallelly aligned plane mirror (R
≈
4%,
λ
/20) under repeatability conditions. The data was post-processed as follows:
Alignment, 5 x 5 median filter with threshold 3 nm (phase evaluation)/40 nm (envelope evaluation), high pass filter
λ
c = 0.25 mm.
5
Measurement noise (N = 1) ·
6
Mean value of measured flatness values (according to ISO 1101) of 50 measurements on a parallelly aligned plane mirror
(R
≈
4%,
λ
/20) under repeatability conditions. The measurements were post-processed as follows: Alignment, 5 x 5 median
filter with threshold 3 nm (phase evaluation)/30 nm (envelope evaluation), low pass filter
λ
c = 0.02 mm.
7
Standard deviation of the measured flatness values (according to ISO 1101) of 50 measurements on a parallelly aligned plane
mirror (R
≈
4%,
λ
/20) under repeatability conditions. The measurements were post-processed as follows: Alignment, 5 x 5
median filter with threshold 3 nm (phase evaluation)/30 nm (envelope evaluation), low pass filter
λ
c = 0.02 mm.
Step Height Measurement on a calibrated Depth Setting Standard
1 2
Nominal step height [µm] 0.24 0.75 7.5 75
Repeatability (Standard Deviation)
3 [µm] 0.02 0.04 0.05 0.06
Maximum Deviation
4 [µm] 0.05 0.12 0.16 0.18
1
Analysis of the correlogram envelope, for usage on unsteady/rough surfaces.
2
15 measurements per step on a calibrated depth setting standard, type KNT 4080/30 (ISO 5436-1)
3
Standard deviation of the measured deviation of the calibrated step height under repeatability conditions.
4 Largest measured deviation in relation to the calibrated step height out of 15 measurements per step under reproducibility
conditions (measured at different sections of the total measurement range, for example).