Features of changes in the electrical resistance of p-Si crystals under the action of an elastic one-axial mechanical load and a magnetic field

Abstract

In thе work, changes in the surface electrical resistance of p-Si crystals were investigated under the simultaneous action of the magnetic field and elastic uniaxial deformation. It was established that a sharp decrease (leap) of resistance occurs at the moment of transition from compression to unclamping at a magnitude of a mechanical load exceeding 18 MPa. Such a leap of resistance is not observed under the elastic uniaxial deformations, which do not exceed 14 MPa. This can be explained by the fact that due to the deeper and more prolonged penetration of the dislocation loops, and the corresponding increase in their length, they accumulate a significant number of charged defects that remain unplaced at the beginning of the release (reduction of the field of mechanical stress). A fluctuation of the resistance value in the direction of increase or towards the reduction occurs in the magnetic field. The diffusion of magnetically sensitive defects into the near-surface region can be explained by the repetition of the processes described in time. In a deformed crystalline lattice, diffusion processes occur more rapidly, which increases the frequency of oscillations of the resistance value. By investigating the IR absorption spectra of experimental samples, it was shown that the decay of defects on the surface (111) of p-Si crystals occurs during a long-term action (288 h) of a constant magnetic field (B = 0.354 T). Such defects are hydrogen-containing and oxygen-containing complexes (Si–O–Si, Si–Si, Si–H₂, Si–C, O–Si–O, Si–O–C, Si–CH₃, H–OH, H₂O, Si–OH). This leads to an increase in the surface resistance of the experimental samples of silicon.