Conversions of a stacking fault to threading dislocations in homoepitaxial diamond growth studied by transmission electron microscopy

Abstract

In this paper, we present how configurations of stacking faults (SFs) in (001)-oriented single crystal diamond substrates changed and extended in the film during homoepitaxial diamond growth by chemical vapor deposition, which was investigated using transmission electron microscopy. In the early stages of the film growth, the SFs in the substrate converted to threading dislocation (TD) rows along the end of the (111) SF planes appearing on the substrate surface, where the direction of the end of the SFs on the surface was [1-10]-[-110]. These TDs then traveled nearly in the same direction tilted by 10° to [-110] from the [001] direction without divergence, while extending with slight divergence within ∼7° in the [110]-[-1-10] direction. The diffraction contrasts observed under several two-beam conditions demonstrated that the SF in the substrate was intrinsic type and had a (111) slip plane with a displacement vector R=-a/3[111], where a is the lattice constant of diamond. At the same time, all the TDs converted from the SFs were edge type and their Burgers vector was b = a/2[1-10], perpendicular to the [001] direction.