Impact of hydrostatic pressure applied at annealing on homogeneity of Si-Ge single crystals

摘要

Creation and transformation of defects in single crystalline (001) oriented Si-Ge with about 5.6 at. % Ge content, containing oxygen interstitials, O _i's, at 9x1017cm-3 level, were investigated, after processing for 5 h at up to 1400 K (HT) under Ar pressure to 1.1 GPa (HP), by X-ray, synchrotron, infrared and photoluminescence methods. To create nucleation centres for O_i's precipitation, some samples were pre-annealed for 10 h at 1000 K under 105 Pa. HT-HP treatment at 1230/1400 K results in improved sample homogeneity and crystallographic perfection. HT-HP induced changes in Si-Ge are related mainly to HP-stimulated diffusivity of Ge.