Distribution of 28Si, 29Si and 30Si isotopes in subsurface layers of Si:B single crystals under plastic deformation

Highlights: • Deformation of Si–B crystals results in ²⁹Si nuclei redistribution on the surface. • ²⁹Si concentration profiles broaden with increase of dislocation density. • ²⁹Si nuclei are substituted by ²⁸Si under deformation. • ²⁹Si¹⁶O complexes migrate more effectively then ²⁸Si¹⁶O under deformation. • Deformation does not affect ³⁰Si isotope distribution. Broadening of the ²⁸Si, ²⁹Si isotope distribution in the subsurface layers of Si:B single crystals under plastic deformation has been observed by secondary ion mass spectroscopy. The ²⁸Si, ²⁹Si profiles broaden with increasing dislocation density. Accompanying changes in the ²⁹Si¹⁶O profile caused by plastic deformation have been found. The shift of the ²⁹Si¹⁶O profile to the crystal bulk correlates well with the ²⁹Si⁺ isotope redistribution. The uphill diffusion or dislocation movement is a possible driving force of Si and SiO redistribution, whereas selectivity of the isotopes in oxidation reaction is provided by singlet–triplet transitions in Si⋯O short living pairs.