EBIC study of recombination activity of oxygen precipitation related defects in si

We describe an electron beam induced current (EBIC) study of the recombination activity of oxygen precipitation related defects (ORD) in nand p-type Si. ORD in as-processed samples exhibit low activity at 300 K, becoming strongly active upon cooling to 80 K. This indicates that shallow levels control their recombination properties. A clear correlation exists between minority carrier diffusion length and density and recombination activity of ORD. Arrhenius-type analyses of the data, based on Shockley-Read-Hall theory, yield activation energies well below 100 meV. Defects in nand p-type material behave in the same way. Contamination with iron gives rise to a dramatic increase of ORD activity at 300 K, resulting in a temperature behaviour characteristic of deep centres. Dislocations surrounding the precipitates appear to be the main recombination sites.