Hall effect single carrier

Analysis of Hall-effect data has been one of the most widely used techniques for studying conduction mechanisms in solids, especially semiconductors. For the single-carrier case, one readily obtains carrier concentrations and mobilities, and it is usually of interest to study these as functions of temperature. This can supply information on the predominant charge-carrier scattering mechanisms and on activation energies, i.e., the energies necessary to excite carriers from impurity levels into the conduction band. Where two or more carriers are present, the analysis becomes more complex, but much more information can be obtained from sludies of the temperature and magnetic held dependencies. 

Polarity of the HALL effect allows the determination of the type of current carriers If essentially simple for single crystal semiconductor samples, HALL coefficient determination for catalytic (i e. mostly powdered) materials requires the greatest care It has been claimed ( 6) ( 7) that it is relatively unaltered by contacts between grains and other hererogeneities in the solid ... 

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