Behaviour of COPs (pits) on substrate surface during growth of thin epitaxial layer-condition of survival as pits on epi surface

Behaviour of COPs during epitaxial growth is investigated for two growth conditions. The critical thickness where COPs disappear depends on the growth conditions. In the case of atmospheric pressure epitaxy using SiHCl₃, the epitaxial thickness where COPs disappear is 0.4 μm. In contrast COPs do not disappear up to 5 μm in the case of reduced pressure epitaxy using SiH₂Cl₂. The shrink of COPs during epitaxial growth depends on the anisotropy of growth; they remain on the epitaxial layer surface when the growth condition is isotropic