Copper complexes in silicon

Abstract

In order to investigate the exchange between copper complexes (Cu centers) in silicon crystal, the change of the photoluminescence (PL) intensity of the Cu center (Cu PL center; no-phonon peak: 1.014 eV) with annealing time was measured for p-type float-zone grown silicon crystals diffused with various concentrations of Cu at 700 °C followed by rapid cooling to room temperature. It was essential to assume the presence of at least one preceding species (precursor) of the Cu PL center to explain the annealing behavior of the PL intensity. Almost the same quantity of the precursor as the Cu PL center was estimated to remain in the as-cooled crystal. The formation energy of the Cu PL center was 0.57±0.05 eV, and dissociation energy was 0.63±0.05 eV. A positive correlation between the precursor of the Cu PL center and the deep level transient spectroscopy center located at Ec−0.15 eV was suggested.