A Japanese company with its roots in the jewelry industry, working alongside university researchers, has developed a new way to mass-produce 2-inch diamond slices. Importantly, these “Kenzan diamonds” are of high enough purity to be useful in applications such as quantum computing. According to the source, just one of these 2-inch diamond slices can be used to store the equivalent of a billion Blu-Ray discs.
Adamant Namiki Precision Jewelry Co., Ltd has collaborated on this diamond wafer mass production technology with Saga University in Kyushu. Previous diamond slices with the purity required for quantum computing applications were severely limited in size. According to the source, it was previously not possible to grow them larger than a 4mm square. Previous attempts to grow 2-inch (~55mm diameter) wafers resulted in levels of nitrogen impurities that made the wafers of little or no use to the computer industry.
The breakthrough of mass production seems to come from the application of the following technique. The diamonds are grown on a sapphire substrate coated with an iridium film, using the principle of “stepped flow growth”, rather than using diamond micro-needle seeding. The substrates used by the new technique and the stepped structure allow diamond growth under high temperatures and pressures, without any stress cracks during cooling. This method of platelet growth also minimizes nitrogen uptake, so it is less than 3 billionths of a percent.
The size and low-nitrogen nature of the new wafers make them useful for quantum storage applications. Using a 2-inch diamond wafer for quantum storage makes it easy to store a billion data-filled Blu-Ray discs. It is also equivalent to the amount of data transmitted by mobile networks during a typical day. By our calculations, that means a single diamond disk can store up to 25 exabytes of data.
Adamant Namiki Precision Jewelry plans to release Kenzan Diamond wafers in 2023. It is already working on developing 4-inch diamond wafers.
Diamonds have unique and attractive qualities for electronic purposes. Last month, we reported on another breakthrough by Japanese scientists, who used diamonds to create very attractive transistors for low-loss power conversion and high-speed communication components.