Korean researchers develop next-gen AI phase-change memory chip with 76% less power, 110% greater durability

South Korean researchers have succeeded in developing a next-generation phase-change memory technology that significantly reduces power consumption by blocking heat diffusion while stably storing multiple data states in a single cell.

The National Research Foundation of Korea announced Friday that a research team led by Korea University Professor Kim Tae-geun had developed a dual-isolation phase-change heterojunction memory that combines two materials with distinct properties to control heat diffusion and phase-change regions inside the memory in a stepwise manner.

As data processing demands surge with the rise of generative AI and large language models, the importance of next-generation memory technology capable of delivering fast operating speeds, low power consumption and high storage density simultaneously has grown considerably.

Conventional phase-change memory, however, has faced a key limitation: heat generated during data writing spreads to surrounding areas, wasting energy and making it difficult to control the phase-change region.

A particularly difficult trade-off existed in which materials that lower operating voltage are vulnerable to heat, while heat-resistant materials require higher voltage.

The research team introduced a new structure that pairs two types of transition metal dichalcogenides — NiTe2 and MoTe2 — both of which can remain in a crystalline state without undergoing phase change during operation.

NiTe2 serves as a thermal conduction layer, efficiently generating and transferring heat even at low voltages, while MoTe2 acts as a thermal barrier layer that suppresses heat diffusion.

This design allows the team to engineer the heat transfer pathway inside the memory, enabling precise control over where and to what extent phase changes occur.

The team verified the operating principles of the proposed structure through electrical characterization, thermal simulation, high-resolution transmission electron microscopy and X-ray diffraction analysis. As a result, they were able to engineer the heat transfer pathway inside the memory as intended, cutting operating energy by 76 percent and improving durability by 110 percent compared with conventional designs.

The significance of the research lies in its departure from the conventional approach of improving a single material's properties. Instead, the team combined NiTe2's high electrical conductivity with MoTe2's high thermal stability within a single device, effectively engineering the flow of heat itself.

"It will be important to further miniaturize the device to actual semiconductor process standards and to secure process stability so that each cell operates uniformly in large-scale memory arrays," Kim said. "We expect this technology to serve as a core memory solution for next-generation semiconductor systems, including high-density AI memory, neuromorphic computing and in-memory computing."

The team plans to conduct follow-up research to verify that multiple resistance states remain stable under repeated operation and extended use, and to ensure compatibility with existing semiconductor manufacturing processes.

The research, supported by the Ministry of Science and ICT and the National Research Foundation of Korea through the Next-Generation Intelligent Semiconductor Technology Development project, was published in the international journal International Journal of Extreme Manufacturing.