Formation of stacking faults containing microtwins in (111) chemical-vapor-deposited diamond homoepitaxial layers

Stacking faults containing microtwins in (111)-oriented diamond layers grown on a high-pressure high-temperature (HPHT)-synthesized diamond substrate by chemical vapor deposition start to form just on the substrate. The microtwins in the stacking faults form on the {(1) over bar 11} plane, not on the (111) substrate plane. To explain these results, we propose an atomic-scale model in which a foreign atom remains on the HPHT substrate surface and a C atom on the foreign atom cannot form a covalent bond with it. Therefore, twinning of the C atom occurs on the {(1) over bar 11} plane. The next C atoms bond with the twinned C atom in an untwinned (normal crystalline) relation. Consequently, the formation of stacking faults that contain microtwins occurs. (C) 2003 American Institute of Physics.