GENERATION OF OXIDATION-INDUCED STACKING-FAULTS IN CZOCHRALSKI-GROWN SILICON-CRYSTALS EXHIBITING A RING-LIKE DISTRIBUTED STACKING-FAULT REGION

The radial density distribution of oxidation-induced stacking faults (OSFs) and bulk micro defects (BMDs) in Czochralski-grown silicon crystals having a ring-like distributed OSF (ring-OSF), region was characterized after low-temperature pre-annealing followed by high-temperature oxidation, using optical microscopy, IR light scattering tomography and Fourier transform IR spectroscopy. Stacking faults were observed to have grown during oxidation in various radial regions of the crystal other than the ring-OS F region, depending on the radial distributions of BMDs determined by the pre-annealing conditions. The ability of these BMDs grown during pre-annealing to nucleate OSFs with subsequent oxidation is determined by the strain surrounding them. However, to realize OSF nucleation, the strain must lie within specific limits controlled by the size of the BMD.