Fig. 3. Microstructural analysis of stacking faults in the high-density stacking-fault diamond (HSD).

a TEM bright-field image of a single grain of HSD-1, with the corresponding SAED pattern shown in the bottom right. b HRTEM image of HSD-1 with the zone axis along [110]. The stacking fault bundle structures are marked by red arrows, and the stacking faults intersections are highlighted with yellow dashed circles. c Statistical distribution of stacking fault spacing in HSD-1. d Three-dimensional schematics illustrating the ultra-dense, three-dimensional interlocked stacking fault network within the sample, along with a stacking fault pyramid structure formed by four equivalent {111} planes, which is oriented perpendicular to the growth direction. e EELS comparison between Area 1 (stacking fault bundle region, red box) and Area 2 (perfect-crystalline region, blue box) in the corresponding ADF image; representative spectra were obtained from three independent experiments showing similar results. f ABF-STEM images comparing the lattice structures of undoped and nitrogen-doped stacking fault, along with corresponding lattice models. g DFT calculated GSFE curves on glide-set plane of undoped diamond and N-doped diamond. Representative images in (a) and (b) are taken from ten independent measurements, showing consistent structural characteristics. Source data are provided as a Source Data file.