Internal friction due to kink motion and kink pair formation in intrinsic and n-doped germanium

Abstract

Measurements of the internal friction on deformed Ge at frequences from 0.2 to 20 Hz at temperatures between 150 and 820 K show two maxima α and β, occuring after deformation only. Their activation enthalpy H, prefactor f0, and relaxation strength Δ are: Hα = (1.108 ± 0.01) eV, f0α = (0.14 to 15) × 109 s−1 (increasing with increasing deformation), Δα ≈︁ 10−2; Hβ = (2.07 ± 0.2) eV, f0β ≈︁ 1013 s−1, Δβ ≈︁ 3 × 10−2). Both shift to lower temperatures with increasing deformation. They are attributed to the movement of geometrical kinks (α) and to kink pair formation (β) on single partial dislocations. Doping with (2 to 4) × 1017 cm−3 Sb lowers the kink migration enthalpy Hα by 0.3 to 0.4 eV. This indicates that the lowering of the activation enthalpy of the dislocation velocity by doping is due to that of the kink migration enthalpy Hα only.

Dislocation Kink Dynamics in Crystals with Deep Peierls Potential Relief

“…The second fitting parameter t 0 allows one to estimate the kink diffusivity with (9) and the kink migration enthalpy with the expression [1] W m kT ln n D b 2 aD k , where n D is the Debye frequency. All the calculated values are in the range W m (1 AE 0.1) eV, those are in reasonable agreement with the ones obtained by other authors [29,30].…”

Anomalous Dislocation Kink Drift in Germanium

“…(6) and the kink migration enthalpy W m with expression [11] W m kT ln͑2n D b 2 ͞D͒, where n D is the Debye frequency. All calculated values are in the range W m 1 6 0.1 eV, those are in reasonable agreement with the ones obtained by other methods [14,20].…”

Electronically enhanced kink motion on 30° partial dislocations in Ge directly observed by plan-view high resolution electron microscopy

“…4. Again, according to internal friction measurements conducted by Jendrich and Haasen, 8 the thermal activation frequency of kink pair formation in Ge is experimentally given by 10 13 ͓s Ϫ1 ͔exp(Ϫ2.1͓eV͔/kT), which predicts a negligible occurrence of kink-pair formation events at room temperature. However, the generated double kinks observed in Fig.…”