The paper presents a significant advancement in laser manufacturing techniques, achieving spatial resolution approaching the quantum limit. The authors introduce a threshold tracking and lock-in (TTL) method to overcome the optical diffraction limit, enabling the creation of feature sizes as small as 5 nm. This method allows for the deterministic generation of single-atom defect complexes (SADCs) in hexagonal boron nitride (hBN), which are crucial for applications such as single-photon emitters, single-electron transistors, and quantum-bit devices. Key findings include: 1. **Threshold Tracking and Lock-in (TTL) Technology**: The TTL method uses additional laser pulses to track the intrinsic threshold of the crystal, allowing for precise control over the damage threshold and enabling the creation of sub-5 nm SADCs. 2. **Close-to-Atom Scale Manufacturing**: The technique demonstrates high reproducibility, high brightness, and high durability of single-photon emitters. The SADCs exhibit high purity and single-photon emission, with minimal background noise. 3. **Quantum Nature of SADCs**: Photon autocorrelation measurements confirm the quantum nature of the SADCs, with antibunching curves indicating single-photon purity. 4. **High Brightness and Durability**: The single-photon emitters show high brightness and stability, with stable count rates and no spectral diffusion or blinking under continuous-wave laser excitation. The study highlights the potential of close-to-atom scale laser manufacturing for scalable quantum photonic technologies, particularly in the context of integrated quantum devices.The paper presents a significant advancement in laser manufacturing techniques, achieving spatial resolution approaching the quantum limit. The authors introduce a threshold tracking and lock-in (TTL) method to overcome the optical diffraction limit, enabling the creation of feature sizes as small as 5 nm. This method allows for the deterministic generation of single-atom defect complexes (SADCs) in hexagonal boron nitride (hBN), which are crucial for applications such as single-photon emitters, single-electron transistors, and quantum-bit devices. Key findings include: 1. **Threshold Tracking and Lock-in (TTL) Technology**: The TTL method uses additional laser pulses to track the intrinsic threshold of the crystal, allowing for precise control over the damage threshold and enabling the creation of sub-5 nm SADCs. 2. **Close-to-Atom Scale Manufacturing**: The technique demonstrates high reproducibility, high brightness, and high durability of single-photon emitters. The SADCs exhibit high purity and single-photon emission, with minimal background noise. 3. **Quantum Nature of SADCs**: Photon autocorrelation measurements confirm the quantum nature of the SADCs, with antibunching curves indicating single-photon purity. 4. **High Brightness and Durability**: The single-photon emitters show high brightness and stability, with stable count rates and no spectral diffusion or blinking under continuous-wave laser excitation. The study highlights the potential of close-to-atom scale laser manufacturing for scalable quantum photonic technologies, particularly in the context of integrated quantum devices.