Evidence on the mechanism of boron deactivation in Ge-preamorphized ultrashallow junctions

We investigate the thermal stability of boron-doped junctions formed by Ge preamorphization and solid phase epitaxial regrowth. Isochronal annealing and characterization by sheet resistance, secondary-ion mass spectrometry, and spreading-resistance measurement are used to extract detailed information on the thermal stability of the boron activation. Using a previously established model of self-interstitial defect evolution from clusters to dislocation loops, we perform simulations of the release of interstitials from the end-of-range region. The simulations indicate that the measured deactivation is driven by interstitials emerging from the end-of-range defect region.