As the microprocessing capacity of Dynamic Random Access Memory (DRAM) chips reaches its limit, a range of research initiatives is underway to transcend these barriers. SK Hynix has underscored the urgent need for advances in patterning, cell capacitors, and low-resistance wiring, with fresh alternatives such as 3D DRAM being touted as possible successors to microprocessing.
Deokshin Gil, Vice President of SK Hynix, told attendees at the ‘2023 Next-Generation Memory Process Equipment/Material/Technology Conference’, held in Seoul’s COEX Tower, “The boundaries of microprocessing in DRAM technology are fast becoming evident, posing significant challenges. To surmount these, we need to explore new platforms like 3D DRAM.”
Vice President Gil underscored the urgency of innovation in patterning, cell capacitors, and low-resistance wiring to break through DRAM microprocessing constraints. Patterning innovation encompasses the implementation of high-NA EUV technology, which raises the exposure lens aberration (NA) from 0.33 to 0.55 in previous-generation tools, facilitating precise patterning.
To improve cell capacitors and low-resistance wiring, material innovation is crucial. Increasing cell capacitor capacity requires a reduction in dielectric thickness, the discovery of High-K materials, and cell structure innovation. Furthermore, research and development are ongoing to find new materials that can enhance low-resistance wiring.
To circumvent microprocessing limits, Gil stated the necessity to advance next-generation memory platforms, like 3D DRAM.
3D DRAM, analogous to 3D NAND flash, is a process technology that enhances performance and space efficiency by vertically stacking DRAM. However, 3D DRAM is still in its nascent stages of development, with its technical concept or specific direction yet to be determined. The industry anticipates that a concrete direction for cell structure will emerge in the next two to three years.
US-based Micron Technology is leading the charge in 3D DRAM research. Micron is focusing on this technology because it has the potential to produce superior DRAM without the need for EUV equipment, once 3D DRAM technology is secured. SK Hynix is also understood to be investigating various next-generation memories, including 3D DRAM.
“Recently, in the course of 3D DRAM research, there are many instances where technologies divergent from 2D DRAM are required,” Gil noted, also highlighting the technical challenges that persist.