The diamond nitrogen-vacancy (N-$V$) center ensemble exhibits substantial potential for room-temperature quantum sensing. However, its practical implementation has long been limited by spectral line broadening and a reduced signal-to-noise ratio, which arise from multiaxis orientations of the N-$V$ centers. The (111) crystal plane is considered an optimal growth direction, as it enables near-perfect axial alignment of N-$V$ centers ($>99\%$) and enhances photon collection efficiency. Nonetheless, the perfect alignment was maintained at the sacrifices, including low growth rates and limited nitrogen-to-N-$V$ conversion efficiencies. In this study, we demonstrate a microwave plasma chemical vapor process in which a growth rate of $94.0\mathrm{\mu }\mathrm{m}/\mathrm{h}$ (14-fold enhancement to the highest previous record) was achieved with uniform N-$V$ ensemble distribution, an N-$V$ concentration of 0.54 ppm, and a nitrogen-to-N-$V$ conversion efficiency of 4.1%–4.7%. The resulting volume-normalized dc and ac magnetic field sensitivities reached $2.15\mathrm{nT}\mathrm{\mu }{\mathrm{m}}^{3/2}{\mathrm{Hz}}^{-1/2}$ and $0.30\mathrm{nT}\mathrm{\mu }{\mathrm{m}}^{3/2}{\mathrm{Hz}}^{-1/2}$, respectively.

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• Color centers
• Quantum information with solid state qubits
• Quantum sensing
• Color center qubits
• Nitrogen vacancy centers in diamond
• Chemical vapor deposition