A vertical edge graphite layer (VEG) fabricated on a diamond (001) substrate and the recovery of the crystallinity of the diamond substrate following high-dose ion implantation and high-temperature annealing (HTA) was investigated. The Al ions were implanted into the diamond (001) surface at 773 K (500 °C), followed by HTA at 1973 K (1700 °C). The graphite edges were vertically oriented, but each domain was randomly rotated in the in-plane direction, which was confirmed via multiple cross-sectional transmission electron microscopy images obtained from different directions rotated 2, 5, 10, and 15° around the  axis. The Raman and photoluminescence exhibited no significant peaks. The initial sp2 structure state of the VEG was nucleated in an early stage of the HTA and the surface diamond was subsequently reconstructed, which was confirmed using stopping-and-range-of-ions-in-matter calculations and Rutherford backscattering/channeling (RBS-C) measurements. The RBS-C spectra indicate that the crystal is maintained after hot implantation and is recovered by HTA. This VEG structure may be useful for ohmic contact with diamond electrical devices.
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