Microstructure of Czochralski silicon annealed at enhanced stress conditions

The microstructure of Czochralski silicon (Cz-Si, containing oxygen interstitials, Oi) treated at high temperatures–pressures (HT–HP) at (1230, 1400) K/(0.01–1.2) GPa was investigated by optical, photoluminescence (PL), X-ray (synchrotron) and related methods. Prior to the HT–HP treatment, Cz-Si was pre-annealed at (720–1000) K/105 Pa to create nucleation centres (NCs) for oxygen precipitation at HT. The samples pre-annealed at (720, 830) K and treated at 1230 K indicate pronounced Oi precipitation with creation of dislocations, while different oxygen-related micro-defects were created in the samples pre-annealed at (920, 1000) K and treated at (1230, 1400 K)/HP. The observed effects are related to stabilisation of NCs and retarded oxygen diffusion at HT–HP.