Impact of Grown-in Point-defects on the Minority Carrier Lifetime in Czochralski-grown Silicon Wafers

In this study, we investigate the nature of some recombination active defects limiting the lifetime in Czochralski (CZ) silicon wafers, in the millisecond range. Due to their low concentrations, the observed defects are unlikely to be identified through Deep-Level Transient Spectroscopy (DLTS) or Electron Paramagnetic Resonance (EPR), hence we use lifetime spectroscopy combine with several annealing steps to help identify the defect. We demonstrate that the defect can be deactivated by annealing above 300 °C. Our experimental findings suggest that vacancy-related pairs incorporated during ingot growth may be responsible for the decreased minority carrier lifetime.