Influence of oxygen on the recombination strength of dislocations in silicon wafers

Oxygen-rich Czochralski and float zone single silicon crystals have been investigated after scratching and plastic deformation in order to generate a dislocation network, under the same experimental conditions. The electrical effects of dislocations have been verified by means of light beam induced current maps at different wavelengths, from which minority carrier diffusion length maps were deduced, and by deep level transient spectroscopy. The maps are well correlated with X-ray topographies and with etch pit distribution. In the oxygen-rich sample, the recombination strength of the dislocations is found to be neatly higher.