Probing coexisting phases and their transition in fully strained epitaxial ferroelectric Hf0.5Zr0.5O2 thin films

Ultra-thin films of ferroelectric doped HfO2 have unexpected ferroelectricity and unusual polarisation mechanisms; combined with their high compatibility with silicon, they have attracted a lot of attention from both fundamental research and application point of view. However, the mechanisms behind these properties remain elusive. Several unanswered questions pertain to the crystal structures of the ferroelectric phase, their transition, and the stabilisation factors. We propose to leverage the capabilities of the diffuse x-ray diffractometer at ID28 to perform in situ, high-temperature studies to unravel the complexities of these phases and their transitions, aiming to shed light on the unique ferroelectric properties of HfO2.

掺杂铁电氧化铪（HfO₂）的超薄薄膜展现出反常的铁电性与非常规极化机制；加之其与硅工艺的高度兼容性，该体系从基础研究到应用探索均受到广泛关注。然而，这些特性背后的物理机制仍未明晰，诸多悬而未决的问题涉及铁电相的晶体结构、相变过程及稳定化机制。本研究拟依托ID28光束线的漫散射X射线衍射仪（diffuse X-ray diffractometer）开展原位高温实验，以解析上述铁电相及其相变的复杂行为，最终阐明氧化铪独特铁电性的内在原理。