‘Quantum breakthrough’ helps superfast diamond-laced computer chips to be much closer to reality

Scientists have taken a major step toward using diamonds in silicon-based computer chips, thanks to advancements in growing diamonds at lower temperatures and applying quantum mechanics. This progress could pave the way for faster, energy-efficient electronics.

Diamonds are highly sought after for electronic applications due to their unique properties. Their crystal lattice structure allows them to handle high electrical voltages and dissipate heat efficiently, while their non-conductive nature makes them ideal for complex systems.

However, the process of making diamonds in the lab has traditionally required extremely high temperatures—too hot for silicon chips to withstand during manufacturing. Reducing these temperatures has often compromised the quality of the diamonds.

A study published in Diamond and Related Materials outlines a breakthrough. Researchers have developed a way to grow diamonds at lower temperatures, making it possible to integrate them into standard silicon chip production.

According to study lead Yuri Barsukov, a computational research associate at Princeton Plasma Physics Laboratory, this method could revolutionize the silicon microelectronics industry. “If we want to implement diamond into silicon-based manufacturing, then we need to find a method of lower-temperature diamond growth,” Barsukov said.

Diamonds are typically produced through a method called plasma-enhanced chemical vapor deposition. This process involves depositing thin films of acetylene gas onto a solid surface. However, past attempts have struggled with soot formation, which reduces the diamond’s effectiveness for use in chips and sensors.

The new study revealed the conditions under which acetylene either contributes to diamond growth or forms soot. Researchers found that the “critical temperature” for this transformation depends on the acetylene concentration and the presence of atomic hydrogen. While hydrogen atoms do not directly grow diamonds, they play a crucial role in enabling their formation even at lower temperatures.

This advancement in diamond growth is just one piece of the puzzle. Another study, published on July 11 in Advanced Materials Interfaces, explored how to enhance diamonds for quantum computing and high-precision sensing. This research focused on creating “quantum diamond” surfaces, where carbon atoms are replaced with nitrogen to form nitrogen-vacancy centers. These centers are critical for harnessing quantum mechanical properties, such as making qubits—the fundamental units of quantum computing.

Qubits differ from traditional bits by holding far more information and processing data in parallel. “The advantage of qubits is that they can hold much more information than regular bits,” said Alastair Stacey, head of quantum materials and devices at PPPL. “This makes them invaluable as sensors, providing detailed environmental data.”

To protect the nitrogen-vacancy centers, scientists aimed to apply a single hydrogen layer to the diamond surface without damaging the underlying structure. Conventional methods involve exposing the diamond to high-heat hydrogen plasma, which risks harming the nitrogen-vacancy centers.

Instead, researchers tested two alternatives: forming gas annealing and cold plasma termination. Both methods proved more effective than traditional approaches, allowing the hydrogen layer to form while minimizing damage.

Although neither technique was flawless, they represented significant improvements. Researchers plan to refine these methods further to create higher-quality hydrogenated diamond surfaces with intact nitrogen-vacancy centers.

These combined efforts bring us closer to a future where diamonds play a key role in advanced electronics, quantum computing, and high-precision sensors.