DEFECTS STATES IN CARBON AND OXYGEN IMPLANTED P-TYPE SILICON

The presence of electrically active defects in C+ and CO + implanted boron-doped silicon has been monitored using deep level transient spectroscopy and resistivity measurements. Activation energies of trapped carriers, implanted ion dependencies, and annealing behavior of these defects have been determined. The introduction of defects by annealing has been observed. A total of ten hole and electron traps are reported. Among these traps, a dominant hole trap 0.65 eV above the valence band, and an electron trap 0.53 eV below the conduction band, are tentatively ascribed to the silicon di-interstitial and the carbon-oxygen pair, respectively. Other traps detected in the samples have been correlated with multi-oxygen- and carbon-related complexes. Annealing at temperatures up to 400 °C gives rise to similar deep level transient spectroscopy spectra comprising the same traps in both C + and CO+ implanted material. However, annealing at temperatures >500 °C produces defect states that are dependent on the implanted ion species.