Si単結晶におけるSi酸化物の析出機構に関する第一原理解析
高濃度B添加の効果
2006 年 72 巻 716 号 p. 369-376
詳細
2006 年 72 巻 716 号 p. 369-376
The mechanism of enhancement for the nucleation and growth of oxide precipitates in heavily boron (B) doped Czochralski (CZ) Si crystals was analyzed by first principles calculation. At initial stage of oxygen precipitation including a few number n of interstitial oxygen (O) atoms with and without one substitutional B atom, i.e. B-On, complex and On, , complex, the reduction of the total energy of stable B-On complex formation was larger than that of stable On complex formation from isolated B and O atoms. The other calculations showed that O atom in B doped silicon diffused as O2+ charge state with the diffusion barrier of about 2.0 eV, which was lower than the barrier of about 2.5 eV for O0 charge stage in intrinsic silicon. This reduction of diffusion barrier should be the mechanism of enhanced oxygen diffusion and enhanced precipitate growth in heavily B doped CZ Si crystals.
