BARRIERS FOR THE KINK MOTION ON DISLOCATIONS IN SI

Kink dynamics on dislocations in Si is studied in a wide stress range (up to 150 MPa) using the intermittent loading (IL) technique. At low stresses (0 to 7 MPa) a two-level IL is employed using selective etching to reveal the dislocations. Dependencies are obtained of the mean dislocation displacements on the pulse and pause durations, as well as on the sign and values of stresses acting during the pulse separation. Experimental data are analyzed in the framework of the kinetic model taking into account diffusion and drift of the kinks. A new method is employed for the measurements of the dynamical properties of geometrical kinks using a combination of IL and transmission electron microscopy (TEM). The displacements of the central parts of the pinned edge dislocations in dipoles are measured in the bulk of Si for different dipole widths in the temperature range 593 to 693 K. Assuming that the displacement of edge dislocation segments is determined by the motion of geometrical kinks, the quantitative parameters of kink motion are obtained by a comparison of the experimental data with computer simulations of the process. A correlation between the dynamical properties of geometrical kinks constituting an edge dislocation and the kink moving along 60-degrees dislocations is discussed in the framework of the theories taking into account the influence of point defects and secondary Peierls relief on the processes of kink pair formation and spreading.