论文标题
RUO2上的vo2薄膜生长大量紧张
Massively strained VO2 thin film growth on RuO2
论文作者
论文摘要
应变工程二氧化钒薄膜是改变该材料特征性一阶从半导体到金属的特征性过渡的一种方法。在这项研究中，我们通过利用沿着金红石结构的C轴沿vo $ _2 $ _2 $/ruo $ _2 $系统的非常大的晶格不匹配来扩展可剥削的应变状态。我们已经在单个域ruo $ _2 $ _2 $ _2 $ _2 $ _2 $的岛上种植了两个不同的表面取向的岛，该岛通过原子氧支持的反应反应性MBE。通过空间分辨的光电子和X射线吸收光谱检查这些薄膜，确认了正确的化学计量。然后，低能电子衍射揭示了vo $ _2 $胶片的成长，确实在ruo $ _2 $（110）上完全紧张，展示了先前未报告的（$ 2 \ times2 $）的重建。在Tio $ _2 $（110）底物上，我们重现了这种重建，并将其归因于高氧化学势引起的富氧终止。另一方面，在Ruo $ _2 $（100）上，这些电影变得完全放松。因此，提出的生长方法允许同时进入一个显着的应变窗口，从散装状结构到大量紧张的区域。
Strain engineering vanadium dioxide thin films is one way to alter this material's characteristic first order transition from semiconductor to metal. In this study we extend the exploitable strain regime by utilizing the very large lattice mismatch of 8.78 % occurring in the VO$_2$/RuO$_2$ system along the c axis of the rutile structure. We have grown VO$_2$ thin films on single domain RuO$_2$ islands of two distinct surface orientations by atomic oxygen-supported reactive MBE. These films were examined by spatially resolved photoelectron and x-ray absorption spectroscopy, confirming the correct stoichiometry. Low energy electron diffraction then reveals the VO$_2$ films to grow indeed fully strained on RuO$_2$(110), exhibiting a previously unreported ($2\times2$) reconstruction. On TiO$_2$(110) substrates, we reproduce this reconstruction and attribute it to an oxygen-rich termination caused by the high oxygen chemical potential. On RuO$_2$(100) on the other hand, the films grow fully relaxed. Hence, the presented growth method allows for simultaneous access to a remarkable strain window ranging from bulk-like structures to massively strained regions.
