摘要
铪基氧化物(Hf(Zr)O_(2))因其优异的铁电性质而成为计算机存储等应用中备受青睐的材料.然而,化学计量比的铪基氧化物基态是非铁电的单斜相.在密度泛函理论计算中,我们发现插入铪或锆原子将随着插入浓度的增加,将Hf(Zr)O_(2)的基态从单斜相转变为三方相.声子色散和态密度投影揭示了插入的Hf(Zr)原子消除了已有的非等效Hf(Zr)原子之间的竞争,从而稳定了r相.此外,Hf/Zr插层原子的有序分布进一步降低了形成能和铁电转换势垒,导致高耐久性和超低的矫顽场.能带结构显示,Hf/Zr插层原子引起的局域平带对漏电流的贡献最小.最后,我们证明了ZrO_(2)对于形成非化学计量比的Hf(Zr)_(1+x)O_(2)至关重要.
The ferroelectricity in hafnium zirconium oxide(HZO) has attracted interest since its discovery in 2011[1].The compatibility with modern complementary metal-oxide-semiconductor(CMOS)technology makes HZO-based materials promising candidates for next-generation memory and logic devices[2-5],such as ferroelectric random-access memory(FeRAM)[6-8]and ferroelectric field-effect transistors(FeFET)[9,10].
作者
陶蕾
张艳芳
杜世萱
Lei Tao;Yan-Fang Zhang;Shixuan Du(School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China;Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China;Songshan Lake Materials Laboratory,Dongguan 523808,China)
基金
supported by the National Key Research and Development Program of China (2022YFA1204100)
the National Natural Science Foundation of China (52102193 and 61888102)
the Fundamental Research Funds for the Central Universities。
