Influence of irradiation by Swift Heavy Ions (SHI) on electronic magnetotransport in Sb δ-layer in silicon

Abstract

In the present paper we report about the influence of Swift Heavy Ions (SHI) irradiation on the electron transport in a silicon structure containing δ -layer heavy-doped with antimony . Temperature and magnetic field dependencies of the sheet resistance R S q ( T , B ) in the temperature range 2 < T < 300 K and magnetic field induction ( B ) up to 8 T of the structure before and after the 167 MeV X e + 26 ion irradiation with 1 ⋅ 10 8 cm −2 – 5 ⋅ 10 10 cm −2 ion fluences ( D ) were measured. The observed R S q ( D , T ) curves for δ -layer have shown the competition between formation and annealing of defects induced by SHI irradiation due to electron stopping mechanism of ion energy loosing. Besides, at temperatures below 50 K, we observed the transition from exponential dependencies of R S q ( T ) to a semi-logarithmic R S q ∼ − lg ( T ) ones both before and after the SHI exposure. Such behavior confirms the assumption that the low-temperature carrier transport is carried out mainly by the δ -layer. Moreover, transition from positive (PMR) to negative (NMR) relative magnetoresistance M R ( B ) was observed when temperature decreasing. The appropriate characteristic times for the carrier scattering process in δ -layer at temperatures below 25 K were estimated from R S q ( T , B ) dependencies using the theory of 2D quantum corrections to Drude conductivity due to interference of electrons moving by self-crossing routes inside of δ -layer. Fitting of R S q ( T , B ) curves in frameworks of this theory indicates prevailing of phase breaking of electrons‘ wave function due to their scattering on weakly-localized defect centers induced by SHI irradiation. • Competition between generation and annealing of defects is due to e -stopping of SHI. • Transition from exponential to a semi-logarithmic R sq (T) dependences below 50 K. • Transition from positive to negative R sq (B) was observed at temperature lowering. • The phase breaking of e wave functions is due to scattering on defects of irradiation. • R sq (T,B) are described by the theory of 2D quantum corrections to Drude conductivity.