Dislocation in heteroepitaxial diamond visualized by hydrogen plasma etching

•The etch pits formed by plasma etching on heteroepitaxial diamond have been clarified by TEM.•The origin of etch pit was mainly [001] threading dislocation.•These dislocations were identified as edge and 45° mixed type.•The correlation between dislocation types and etch pit shape

The classification of etch pits formed by hydrogen plasma etching on heteroepitaxial diamond has been done by cross-sectional transmission electron microscope (TEM). We demonstrated that the origin of etch pit was mainly [001] threading dislocation. From invisibility criterion of dislocation contrast in TEM observation, this dislocation was identified as edge and 45° mixed dislocation. The correlation between dislocation types and etch pit shape was discussed.