Precise measurement of density and structure of undercooled molten silicon by using synchrotron radiation combined with electromagnetic levitation technique
Precise measurement of density and structure of undercooled molten silicon by using synchrotron radiation combined with electromagnetic levitation technique
复制标题
DOI：
10.1088/0957-0233/16/2/008
复制
发表时间：
2005-02-01
影响因子：
2.4
通讯作者：
Kuribayashi, K
中科院分区：
文献类型：
--
作者：
Higuchi, K;Kimura, K;Kuribayashi, K
利用电磁悬浮技术，同时进行了x射线衍射和密度测量，在包括过冷区在内的宽温度范围内研究了熔融硅的原子结构。采用基于图像分析技术的非接触方法，从悬浮样品的质量和形状得到密度。利用同步辐射在日本SPring8进行了x射线衍射实验。在1900 ~ 1550 K范围内，硅熔体的第一近邻配位数和原子间距离分别为5和2.48埃，与温度无关。结果表明，过冷硅熔液的四面体键的近程顺序不随过冷程度的变化而变化，而中程顺序随过冷程度的变化而变化。
X-ray diffraction and density measurements have been simultaneously performed to investigate the atomic structure of molten silicon in a wide temperature range including the undercooling region by using the electromagnetic levitation technique. The density was obtained from the mass and the shape of a levitated sample by a non-contact method based on the image analysis technique. X-ray diffraction experiments were performed by using the synchrotron radiation at SPring8, Japan. From structural analysis of undercooled molten silicon, the first nearest neighbour coordination numbers and interatomic distances were about 5 and 2.48 Angstrom with no dependence on temperature in the range of 1900-1550 K. We conclude as a result that the short-range order based on tetrahedral bonds of undercooled molten silicon does not change with the degree of undercooling but that medium-range order changes by the degree of undercooling.