Diffusion of implanted sodium in oxygen-containing silicon

The effect of oxygen on diffusion of sodium implanted into silicon is studied for the first time in the temperature range from 500 to 850°C. A high-resistivity p-Si (ρ > 1 kΩ cm) grown by the Czochralski method in a magnetic field (mCz) with the oxygen concentration ～3 × 10¹⁷ cm^?3 was used. For comparison, we used silicon grown by the crucibleless floating zone method (fz). Temperature dependences of the effective diffusion coefficient of sodium in the mCz-Si and fz-Si crystals were determined and written as D _mCzcm²/s] = 1.12exp(?1.64 eV/kT) cm²/s and D _fzcm²/s] = 0.024exp(?1.29 eV/kT) cm²/s, respectively. It is assumed that larger values of diffusion parameters in oxygen-containing silicon are caused by formation of complex aggregates that contain sodium and oxygen atoms.