Ningbo company grows diamonds for jewelry and chips

A CVD single-crystal diamond produced by Ningbo Crysdiam Technology. [Photo/Yongpai app]

Ningbo Crysdiam Technology is expanding the use of CVD synthetic diamonds beyond jewelry, with its products increasingly finding applications in semiconductors, quantum technologies, and other advanced industries.

At the company's production facility in Ningbo, rows of microwave plasma chemical vapor deposition (MPCVD) reactors operate around the clock, growing diamonds in a controlled environment.

Inside the reactors, carbon atoms are deposited layer by layer onto a diamond seed crystal under low pressure and temperatures exceeding 900 C, gradually forming larger single-crystal diamonds.

Crysdiam was among the first companies in China to commercialize chemical vapor deposition (CVD) diamond production.

More than a decade ago, while many domestic producers relied on high-pressure, high-temperature methods, the company adopted MPCVD technology and went on to develop China's first domestically designed MPCVD growth system.

It also produced the country's first large single-crystal CVD diamond, and established China's first industrial-scale production line for the material.

Today, the company operates 1,500 self-developed growth reactors and has an annual production capacity of 2.5 million carats, which it says ranks first globally. According to the company, its products hold the largest market share in China and rank among the top two worldwide.

The size of the diamonds varies according to customers' needs. Company representatives said single-crystal diamonds can be grown to a thickness of 13 to 14 millimeters for jewelry applications, while industrial-grade products can exceed three inches in diameter for use in sectors such as semiconductors.

Beyond gemstones, CVD diamonds are increasingly valued for their exceptional thermal conductivity, hardness, and optical properties. The material is being used in ultra-precision machining, optical windows, quantum communication, and heat-management solutions for integrated circuits.

According to the company, demand currently exceeds supply as new industrial applications continue to emerge.