Korean researchers open path to mass production of graphene with 'K-sputtering' technology

South Korean researchers have developed a technique to grow graphene — long dubbed a "dream material" — directly on substrates at room temperature, without applying heat. The breakthrough is expected to accelerate development of next-generation copper-graphene composite conductors designed to reduce power loss and heat generation in electric vehicles and AI data centers.

The Korea Electrotechnology Research Institute (KERI) announced Sunday that a research team led by Dr. Kim Ho-seop and researcher Nam Su-hyeon of its Power Cable Research Center had successfully grown graphene-based thin films at room temperature using a proprietary direct-current device and process they call "K-sputtering."

Graphene is a thin material in which carbon atoms are arranged in a honeycomb lattice. Its exceptional electrical and thermal properties make it a promising candidate for next-generation high-performance conductors when combined with copper, offering reduced power loss and heat generation.

The challenge has long been in the manufacturing process. Producing high-quality graphene through the conventional chemical vapor deposition method requires a separate "transfer process" to move the graphene onto another material. Large-area fabrication is difficult, and the method has also limited the mass production of composite conductors that require multiple alternating layers of metal and graphene.

The research team found a way forward in sputtering, a thin-film deposition technique already widely used in the semiconductor and display industries. Sputtering works by dislodging material into fine particles and depositing them onto a substrate.

The problem is that depositing carbon by sputtering tends to produce a disordered film in which atoms are not properly aligned — making it difficult to grow high-quality graphene with a regular atomic structure directly on a substrate.

The team analyzed the flow and behavior of carbon particles during sputtering to identify what was disrupting graphene structure formation. Based on those findings, they independently developed a DC-based K-sputtering device and process that precisely controls the conditions under which carbon particles arrange themselves on the substrate.

The key is epitaxial growth. Rather than depositing carbon randomly, the technique guides carbon atoms to align with the crystal orientation of the substrate, stacking them in an orderly fashion like building blocks placed along a template.

Using this approach, the team succeeded in growing everything from single- and double-layer graphene to multilayer graphite directly at room temperature, with no separate heating step required. Within the scope of the team's review, this marks the first time that aligned graphene-based carbon thin films have been grown directly using a sputtering method.

A key advantage of the technology is that it relies on sputtering equipment already in widespread industrial use. It also allows copper and graphene to be deposited in alternating layers — as many times as needed — within a single piece of equipment, eliminating the need for a complex transfer process.

Building on this, the team plans to develop an ultra-high-performance composite conductor that combines copper's electrical conductivity with graphene's strengths. The material is expected to be applicable to high-power electrical devices such as AI data centers and electric vehicles, where power consumption and heat generation are rising sharply.

"After much trial and error, we have experimentally confirmed that it is possible to produce graphene-based thin films with regularly aligned carbon atoms using a sputtering method," Kim said. "Going forward, we will scale up the equipment and advance toward continuous production to lead the commercialization of high-performance composite conductors — with alternating layers of copper and graphene — for use in power devices."

The findings were published in Surface & Coatings Technology, an international journal covering materials surface and coating research. The team has also filed three domestic patents and one international patent related to the technology.