Wafer-scale Integration of Nanodiamonds Via Electrostatic-Trapping Achieves 82.5% Yields for Scalable Devices

Nanodiamonds hold immense promise for revolutionising nanoscale sensing, imaging and communication, but realising practical devices requires arranging these tiny building blocks with precision and scalability. Jixiang Jing, Yicheng Wang, and Zhuoran Wang, along with their colleagues, have now developed a method to rapidly and reliably integrate single nanodiamonds across entire eight-inch wafers. The team achieves this by employing electrostatic forces to capture nanodiamonds within carefully engineered microscale hole templates, demonstrating an impressive 82. 5% yield within just five minutes. This breakthrough overcomes a significant hurdle in nanodiamond technology, offering a pathway to mass production and paving the way for the widespread commercial adoption of nanodiamond-based devices, while also being compatible with existing CMOS manufacturing processes.

Nanodiamonds are key materials for building nanoscale quantum sensing, imaging and communication devices. Researchers have now developed a deterministic and scalable approach to position single nanodiamonds with high precision, achieving a 91. 2% success rate for single nanodiamond placement. This allows for the creation of complex, user-defined nanodiamond arrays with a spatial resolution of 300 nanometres, enabling the fabrication of advanced quantum photonic circuits and overcoming limitations imposed by random placement and low-density integration.

Nanodiamond Arrays via Electrostatic Trapping and Lithography

This research focuses on a novel method for precisely positioning individual nanodiamonds using a combination of photolithography, surface modification, and electrostatic forces to create highly ordered nanodiamond arrays. The technique utilizes nanoscale template holes created in a silicon substrate, modified to create a positive surface charge attracting the negatively charged nanodiamonds. Kelvin Probe Force Microscopy confirms the successful creation of this positive surface potential, and researchers successfully trapped individual nanodiamonds within these template holes, finding that hole size is critical for successful trapping. Computational modeling accurately predicted the electrostatic potential within the holes, identifying the optimal region for trapping, and demonstrated the creation of stable 25×25 arrays for several hours.

Electrostatic Trapping Yields Nanodiamond Arrays Rapidly

Scientists have developed a technique for precisely positioning nanodiamonds on various surfaces, enabling the rapid and reliable creation of nanodiamond arrays across large, eight-inch wafers with an impressive 82. 5% yield within just five minutes. This method utilizes carefully engineered microscale hole templates and electrostatic force to capture single nanodiamonds, demonstrating that the number of nanodiamonds deposited is primarily determined by the diameter of the trapping holes. Systematic studies show that negatively charged nanodiamonds are effectively trapped within positively charged, amino-modified holes, confirming electrostatic attraction as the driving force. Theoretical modeling demonstrates a non-uniform electrostatic potential within the holes, guiding the nanodiamonds towards the center and bottom, and measurements confirm that most trapped nanodiamonds concentrate within 500 nanometers of the hole’s center, demonstrating high positional accuracy. This technique proves highly reproducible, consistently achieving single nanodiamond placement across 25×25 arrays and is compatible with existing CMOS technologies, allowing for integration onto silicon waveguides, gallium nitride pillars, and gold microwave antennas.

Rapid Nanodiamond Assembly on Eight-Inch Wafers

This research demonstrates a new method for rapidly and reliably assembling arrays of single nanodiamonds on substrates used in standard microchip fabrication, achieving high yields of 82. 5% within a five-minute timeframe. The technique utilizes carefully designed microscale hole templates and electrostatic forces to capture and position the nanodiamonds, and the team’s approach is notable for its simplicity, reproducibility, and compatibility with current manufacturing technologies. Experimental and computational results confirm that the shape of the trapping template, specifically an hourglass-like channel within the holes, controls the passage of individual nanodiamonds, enabling precise placement, and the method successfully integrated nanodiamond arrays onto diverse platforms, including silicon waveguides, gallium nitride pillars, and gold microwave antennas. This breakthrough is expected to accelerate the development and commercialization of nanodiamond-based technologies in areas such as quantum sensing, imaging, communication, and computing, offering a scalable pathway towards practical nanoscale devices.