Mutilin Sergey V, Yakovkina Lyubov V, Seleznev Vladimir A, Prinz Victor Ya
Rzhanov Institute of Semiconductor Physics SB RAS, 13 Lavrentiev Aven., 630090 Novosibirsk, Russia.
Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Lavrentiev Aven., 630090 Novosibirsk, Russia.
Materials (Basel). 2022 Nov 7;15(21):7863. doi: 10.3390/ma15217863.
In the present article, the position-controlled and catalytic-free synthesis of vanadium dioxide (VO) nanowires (NWs) grown by the chemical vapor deposition (CVD) on nanoimprinted silicon substrates in the form of nanopillar arrays was analyzed. The NW growth on silicon nanopillars with different cross-sectional areas was studied, and it has been shown that the NWs' height decreases with an increase in their cross-sectional area. The X-ray diffraction technique, scanning electron microscopy, and X-ray photoelectron spectroscopy showed the high quality of the grown VO NWs. A qualitative description of the growth rate of vertical NWs based on the material balance equation is given. The dependence of the growth rate of vertical and horizontal NWs on the precursor concentration in the gas phase and on the growth time was investigated. It was found that the height of vertical VO NWs along the [100] direction exhibited a linear dependence on time and increased with an increase in the precursor concentration. For horizontal VO NWs, the height along the direction [011] varied little with the growth time and precursor concentration. These results suggest that the high-aspect ratio vertical VO NWs formed due to different growth modes of their crystal faces forming the top of the growing VO crystals and their lateral crystal faces related to the difference between the free energies of these crystal faces and implemented experimental conditions. The results obtained permit a better insight into the growth of high-aspect ratio VO NWs and into the formation of large VO NW arrays with a controlled composition and properties.
在本文中，分析了通过化学气相沉积（CVD）在纳米压印硅衬底上以纳米柱阵列形式生长的二氧化钒（VO）纳米线（NWs）的位置控制和无催化合成。研究了在具有不同横截面积的硅纳米柱上的NW生长情况，结果表明NWs的高度随着其横截面积的增加而降低。X射线衍射技术、扫描电子显微镜和X射线光电子能谱表明所生长的VO NWs质量很高。基于物料平衡方程对垂直NWs的生长速率进行了定性描述。研究了垂直和水平NWs的生长速率对气相中前驱体浓度和生长时间的依赖性。发现沿[100]方向的垂直VO NWs的高度与时间呈线性关系，并随着前驱体浓度的增加而增加。对于水平VO NWs，沿[011]方向的高度随生长时间和前驱体浓度的变化很小。这些结果表明，高纵横比的垂直VO NWs是由于形成生长VO晶体顶部的晶面及其侧面晶面的不同生长模式而形成的，这与这些晶面的自由能差异以及实施的实验条件有关。所获得的结果有助于更好地理解高纵横比VO NWs的生长以及具有可控组成和性能的大型VO NW阵列的形成。
