Seoul National University researchers find key to next-gen memory

Researchers at Seoul National University have observed the real-time crystallization of Hafnium-Zirconium-Oxide (HZO), a material being studied for next-generation nonvolatile memory chips. The study, published in ‘Advanced Functional Materials’, reveals that microscopic defects known as oxygen vacancies significantly influence the material's performance and crystalline structure.

HZO is a promising candidate for low-power memory because it is compatible with existing silicon semiconductor manufacturing and maintains ferroelectric properties even at thicknesses of only a few nanometers. For the material to function effectively for data storage, it must achieve a specific, stable orthorhombic crystal structure.

By using high-resolution X-ray radiation at the Pohang Accelerator Laboratory, the research team, led by Min Hyuk Park and Hyun Woo Jeong, tracked how varying concentrations of oxygen vacancies affect the onset of crystallization and the resulting phase. This discovery provides a pathway to better control the formation of the orthorhombic phase, which is essential for maintaining electrical states without power.