Negatively charged nitrogen-vacancy $\left({\mathrm{NV}}^{-}\right)$ centers located a few nanometers below the diamond surface are key quantum defects for nanoscale sensing of external spins. However, the creation of shallow ${\mathrm{NV}}^{-}$ centers with high yield remains a materials challenge. Here, we demonstrate that high-angle ion implantation enhances the creation efficiency of shallow ${\mathrm{NV}}^{-}$ centers. By implanting ${}^{15}\mathrm{N}$ ions at angles exceeding ${60}^{\circ }$, we achieve high ${\mathrm{NV}}^{-}$ yields approaching 10% with effective ${\mathrm{NV}}^{-}$ depths below 10 nm. These yields are significantly higher than those typically reported for shallow ${\mathrm{NV}}^{-}$ creation. The enhanced ${\mathrm{NV}}^{-}$ yield is consistent with an increased vacancy-to-nitrogen ratio in the near-surface region, which is expected to promote NV formation during annealing. The created ${\mathrm{NV}}^{-}$ ensembles show coherence properties comparable to those of single shallow ${\mathrm{NV}}^{-}$ centers at similar depths, and allow detection of nuclear spins in van der Waals materials attached to the diamond surface. Our results establish geometric control of ion implantation as a simple and broadly applicable approach to engineer shallow vacancy-related quantum defects.

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• Color centers
• Nitrogen vacancy centers in diamond
• Point defects
• Quantum sensing
• Ion implantation
• Nuclear magnetic resonance
• Optically detected magnetic resonance