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Measurement of Hall voltage and resistivity. Measurement of Sheet Resistivity. Measurement of Hall voltage. where. Resistivity. Here, t = thickness of the sample. Variation of F with Q. F(Q) = 1, if R A = R B.
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Measurement of Hall voltage and resistivity Measurement of Sheet Resistivity Measurement of Hall voltage where Resistivity Here, t = thickness of the sample
Variation of F with Q F(Q) = 1, if RA = RB
For Hall measurements the magnitude of the magnetic field should be small to avoid magneto-resistance or reduction in conductance due to the magnetic field Measurement of both mobility and sheet charge density is possible The volume density of carriers is possible to estimate if the thickness of the sample is known The sign of the charge carriers can be found from the sign of the Hall voltage Advantageous for samples having 2DEG since direct measurement of sheet charge density can be made unlike CV technique Hall measurement includes overall effects of both majority and minority carriers Summary of the Hall measurement
Hall Effect sensor: Chip and Spec ANALOG DEVICES - AD22151YRZ - IC, HALL EFFECT SENSOR, LINEAR, 8-SOIC
Ionized impurity scattering Acoustic phonon scattering Polar optical scattering Alloy scattering Defect related scattering Scattering processes in bulk GaAs Note that ionized impurity scattering is extremely important, and dominates all other for higher doping concentrations Matthiessen rule for total mobility calculation: