Electrically active defects in shallow pre-amorphised p super(+)n junctions in silicon

An examination of shallow pre-amorphised p super(+)n junctions in silicon has revealed three distinct defect related phenomena determined largely by the annealing temperature and relative location of the junction and the amorphous-crystalline ( alpha -c) boundary. For temperatures below 800 degree C all samples displayed leakage currents of similar to 10 super(-3) A/cm super(2) irrespective of the amorphising atom (Si super(+), Ge super(+), or Sn super(+)). The generation centres responsible were identified to be near mid-gap deep level donors lying beyond the alpha -c interface. For samples annealed above 800 degree C, the leakage current was determined by the interstitial dislocation loops at the alpha -c boundary. From the growth of these loops during furnace annealing it was concluded that the growth was supported by the influx of recoil implanted silicon interstitials initially positioned beyond the alpha -c boundary.