Evaluation of stress tensor around a threading defect in diamond: Application of NV center-based measurement and comparative multi-modal analysis

Threading defects in diamond degrade the performance of diamond-based quantum and electronic devices. Although the disorder of the atomic arrangement induced by the threading defects is considered to be the cause of the performance degradation, yet quantitative and spatially resolved evaluation of the stress tensor that characterizes the magnitude of the disorder has remained challenging. In this study, we applied the evaluation technique of the stress tensor based on nitrogen-vacancy (NV) centers to the mapping of the stress field around a threading defect in a chemical vapor deposition diamond film. Furthermore, we compared the stress tensor measured using NV centers with that obtained by conventional methods such as Raman spectroscopy and x-ray topography. Around the threading defect, the components of the stress tensor σxy, σyz, σzx, and σxx + σyy + σzz varied by approximately 0.2, 0.2, 0.3, and 1.2 GPa, respectively, and each component exhibited a rotationally symmetric distribution extending over a diameter of approximately 10–20 μm. We calculated the Raman shift mapping from the stress tensor obtained using NV centers, and the Raman peak was estimated to decrease by approximately 0.9 cm−1 due to the stress tensor at the center of the threading defect. This value was comparable to the experimental result of Raman shift mapping. These results indicate that the components of the stress tensor measured by NV centers accurately reflect the stress induced by the threading defects. The stress tensor and x-ray topography images suggest that the threading defect measured in this study was a bundle dislocation.