The transport of charges investigated by Hall Efiect

Voltages across a germanium crystal are recorded on a range of tem- peraturesgoingfrom150to383K.Impurities,temperatureandthepres- ence of a magnetic fleld (causing the Hall efiect and magnetoresistance) modify the mechanism of conduction. Measurements of the temperature dependenceoftheresistivity ‰togetherwiththeHallcoe-cient RH give informationonseveralpropertiesofthesemiconductor. Then-typenature ofthedopanthasbeensuccessfullyestablishedanditsconcentration,ap- proachedbyafactoroftwo. Thebandgapenergy Eg measuredwasfound intherightrangeofexpectedvalues. Finally,twotypesofchargecarriers' mobilities were discriminated and the power law of ‰(T) in the intrinsic regionwasverifled,aswellasthepowerlawfor ‰(B)(magnetoresistance).