Spin-Dependent Transport of Charge Carriers in Silicon Microcrystals Doped with Boron and Diluted with Nickel

Negative magnetoresistance of Si p-type whiskers with different impurity concentration $10^{18} - 5\times 10^{18}$ cm−3 which corresponds to the transition of a metal-dielectric in silicon and diluted with nickel were studied in longitudinal magnetic field 0–14 T in the temperature range 4.2–77 K. The large negative magnetoresistance values correspond to hopping conductance on the twice occupied by electrons impurity states. It is established that in order to predict the magnetoresistance of crystals, it is necessary to take into account the polarization component due to the nature of the hopping conductance at low temperatures