Experimental studies to determine the formation energies of vacancies in Si and Ge crystals have been performed since the 1950s, but have been unsuccessful. We studied the formation and migration energies of a vacancy and an interstitial by detecting complexes of point defects and hydrogen atoms by optical absorption measurement. The formation energies of the vacancy and interstitial were found to be 3.85 ± 0.15 and 4.8 + 0.6/%0.4 eV, respectively. The migration energies of the vacancy and interstitial were 0.45 ± 0.04 and 0.49 ± 0.05 eV, respectively. Using these energies, we determined the activation energies of the vacancy- and interstitial-mediated self-diffusion to be 4.30 ± 0.19 and 5.3 + 0.6/ %0.4 eV, respectively. The former energy is especially important since there has been no study in which vacancy-mediated diffusion has been successfully determined.
ASJC Scopus subject areas
- Physics and Astronomy(all)