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D
Ensure that the temperature of the sample is as stable as possible. Insert the
sample into the magnet, wait 1 h, then re-run the test.
A.6.5.4 InAs Measurement Troubleshooting
If the InAs test shows up as p type in the AC mode, but n type in the DC mode, perform
the following checks.
D
If the InAs material values (resistivity, carrier density or mobility) have changed
significantly from previous tests, inspect the InAs for cracks or other damage.
D
Recalibrate the AC magnetic field.
A.6.5.5 AC/DC Comparison Troubleshooting
An AC/DC comparison should be made between the carrier density, mobility, and Hall
coefficient. Do not directly compare Hall voltage since this depends on the magnetic
field. The AC and DC test may be done at different fields. The calculation of Hall
coefficient, density and mobility take into account the different magnetic fields. If the
AC and DC Hall values do not agree, perform the following checks, and then re-run the
field calibration.
D
Make sure all wires on the sample are as short as possible and do not have un-
necessary loops.
D
Make sure the temperature of the sample is as stable as possible. Insert the sam-
ple into the magnet, wait 1 h, then re-run the test.
Summary of Contents for Measure Ready M91 FastHall
Page 6: ...MeasureReady M91 FastHall Measurement Controller ...
Page 10: ...MeasureReady M91 FastHall Measurement Controller ...
Page 64: ...54 cHAPTER 3 Operation MeasureReady M91 FastHall Measurement Controller ...
Page 156: ...146 cHAPTER 4 Computer Interface Operation MeasureReady M91 FastHall Measurement Controller ...
Page 160: ...150 cHAPTER 5 Options and Accessories MeasureReady M91 FastHall Measurement Controller ...
Page 174: ...164 cHAPTER 6 Service MeasureReady M91 FastHall Measurement Controller ...