HOLE MOBILITY IN ALUMINUM IMPLANTED SILICON

The dependence of the hole mobility on the dopant concentration rangin g from 5 x 10(15) to 1 x 10(19) atoms/cm(2) was determined at room tem perature in Al-implanted Si samples. The trend was obtained by the use of Hall effect and resistivity measurements on the van der Pauw patte rn in combination with secondary-ion mass spectrometry and spreading r esistance analysis. The mobility data are in a quite good agreement wi th the Wagner curve for boron in the high Al concentration region whil e they approach the Thurber boron curves at low concentrations. This r esult indicates that the neutral and ionized impurity scattering mecha nisms are not critically different for Al-and B-doped samples. The mob ility-dopant concentration curve can be employed to convert the resist ivity profiles obtained by spreading resistance measurements into hole concentration distributions for Al-doped samples.