Wang Yuan, Tao Lei, Guzman Roger, Luo Qing, Zhou Wu, Yang Yang, Wei Yingfen, Liu Yu, Jiang Pengfei, Chen Yuting, Lv Shuxian, Ding Yaxin, Wei Wei, Gong Tiancheng, Wang Yan, Liu Qi, Du Shixuan, Liu Ming
State Key Lab of Fabrication Technologies for Integrated Circuits, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, China.
Key Laboratory of Microelectronics Devices and Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences, Beijing, China.
Science. 2023 Aug 4;381(6657):558-563. doi: 10.1126/science.adf6137. Epub 2023 Aug 3.
Hafnium oxide-based ferroelectric materials are promising candidates for next-generation nanoscale devices because of their ability to integrate into silicon electronics. However, the intrinsic high coercive field of the fluorite-structure oxide ferroelectric devices leads to incompatible operating voltage and limited endurance performance. We discovered a complementary metal-oxide semiconductor (CMOS)-compatible rhombohedral ferroelectric Hf(Zr)O material rich in hafnium-zirconium [Hf(Zr)]. X-ray diffraction combined with scanning transmission electron microscopy reveals that the excess Hf(Zr) atoms intercalate within the hollow sites. We found that the intercalated atoms expand the lattice and increase the in-plane and out-of-plane stresses, which stabilize both the rhombohedral phase (r-phase) and its ferroelectric properties. Our ferroelectric devices, which are based on the r-phase Hf(Zr)O, exhibit an ultralow coercive field (~0.65 megavolts per centimeter). Moreover, we achieved a high endurance of more than 10 cycles at saturation polarization. This material discovery may help to realize low-cost and long-life memory chips.
基于氧化铪的铁电材料因其能够集成到硅电子器件中，是下一代纳米级器件的有前途的候选材料。然而，萤石结构氧化物铁电器件固有的高矫顽场导致工作电压不兼容且耐久性性能有限。我们发现了一种与互补金属氧化物半导体（CMOS）兼容的富含铪锆[Hf(Zr)]的菱面体铁电Hf(Zr)O材料。X射线衍射结合扫描透射电子显微镜表明，过量的Hf(Zr)原子插入到中空位置。我们发现，插入的原子使晶格膨胀并增加面内和面外应力，这稳定了菱面体相（r相）及其铁电性能。我们基于r相Hf(Zr)O的铁电器件表现出超低矫顽场（约0.65兆伏/厘米）。此外，我们在饱和极化下实现了超过10次循环的高耐久性。这一材料发现可能有助于实现低成本和长寿命的存储芯片。
