High crystalline quality single crystal CVD diamond

Understand

Homoepitaxial chemical vapour deposition (CVD) on high pressure high temperature (HPHT) synthetic diamond substrates allows production of diamond material with controlled point defect content.

• In order to minimize the extended defect content, however, it is necessary to minimize the number of substrate extended defects that reach the initial growth surface and the nucleation of dislocations at the interface between the CVD layer and its substrate.
• X-ray topography has indicated that when type IIa HPHT synthetic substrates are used the density of dislocations nucleating at the interface can be less than 400 cm-2.
• X-ray topography, photoluminescence imaging and birefringence microscopy of HPHT grown synthetic type IIa diamond clearly show that the extended defect content is growth sector dependent.