Mechanism of generation and suppression of misfit dislocations in Si bulk crystal growth at the seed/crystal interface is studied. Misfit dislocations in B-doped CZ-Si crystal growth are suppressed when the difference in B concentration between a seed and the grown crystal is at least 9 × 10 18 cm3, corresponding to 4.5 × 105 of misfit strain. Similar misfit strain of 3.4 × 105 was obtained in Ge-doped CZ-Si crystal growth. In the CZ-Si crystal growth, a transition region of impurity concentration with about 40 μm in width is formed at the seed/crystal interface in both dislocation-free and dislocated crystals by diffusion of impurity atoms from the seed. From a macroscopic viewpoint at the seed/crystal interface, the critical misfit strain in Si bulk crystal growth is larger than that in epitaxial growth model in a consideration that the width of the transition region is the critical thickness of the grown layer. We propose a preliminary new mechanism of generation and suppression of misfit dislocations dependent on the local misfit strain at the interface during the growth from a microscopic viewpoint.
|Number of pages||6|
|Journal||Physica Status Solidi (C) Current Topics in Solid State Physics|
|Publication status||Published - 2009 Dec 7|
|Event||International Conference on Extended Defects in Semiconductors, EDS 2008 - Poitiers, France|
Duration: 2008 Sep 14 → 2008 Sep 19
ASJC Scopus subject areas
- Condensed Matter Physics