Next Generation Memory Devices using Metal-Halide Perovskite Design
Next Generation Memory Devices using Metal-Halide Perovskite Design
  • Reporter Lee Seung-Joo
  • 승인 2020.07.14 18:44
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▲Prof. Lee Jang-Sik (MSE) on the left and Prof. Lee Donghwa (AMS)
▲Prof. Lee Jang-Sik (MSE) on the left and Prof. Lee Donghwa (AMS)

Professor Lee Jang-Sik (MSE) and Prof. Lee Donghwa (AMS)’s co-research team recently succeeded in designing a new halide perovskite (HP) with high environmental stability and low-operating voltages, making it suitable for resistive switching memory (RSM). Combined first-principles screening based on quantum mechanics and experimental verification have been utilized to establish such findings.
Even with the consistent development in memory technology, the exponentially increased usage of fast and high-quality data transfer requires further improvement in memory technology to increase overall stability. HP, due to its fast-ionic motion in crystal structure, has been identified as a possible alternative that can result in better performance in memory application. However, its poor stability hinders its practical applications for memory devices.
Using first-principles screening and experimental verification, the two professors determined the 2D layered AB2X5 structure as a prominent candidate for memory device due to lower formation energy. For verification, memory devices based on all-inorganic 2D-layered CsPb2Br5 was synthesized. Screening results based on the formation energy and defect formation energy predicted clear superiority of CsPb2Br5 over 3D- or other 2D-layered structures. While the original 3D structures tended to lose memory properties when temperatures exceeded 100˚C, the tested 2D structures maintained its properties up to 140˚C and operated under voltages as low as 1V. CsPb2Br5-based memory device exhibited lower set electric field and higher ON/OFF ratio, verifying superior performance. In summary, the combined first-principles screening and experimental verification have successfully predicted that CsPb2Br5-based memory shows superior resistive switching behavior and thermodynamic stability.
Prof. Lee Jang-Sik claimed that “This material was derived using computer simulation to meet the requirement for memory device purposes. Memory devices using such material can be used for fields such as mobile devices that require low-voltages or servers that require high stability. From this research it is expected to expedite the commercialization of high-quality next generation memory devices.”
Meanwhile, this research was supported by Creative Materials Discovery Program and Mid-career research program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT.