The Formation and Growth Mechanism of iron-oxide nanorod on single crystal MgO(100),(110),and(111) substrates

• Main Authors: Jhij-heng Luo, 羅志恆
• Other Authors: G.Chen
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/09928401716342906489

碩士 === 國立中正大學 === 物理所 === 94 === In recent years, the nanomaterial is gradually noticeable, and the researchs about the iron oxide nanorod are very much. The majority of study is discussing that temperature and oxygen content to the iron oxide nanorod being influenced, and the structure of the iron oxide nanorod. But the formation mechanism of the iron oxide nanorod was not explained clearly.We use the Sputtering System to grow the thin films of Fe on the Si(100) substrate which thickness are 50nm and 500nm, and use the Molecular Beam Epitaxy to grow the thin films of Fe on the single crystal substrates including MgO (100) , (110) , (111) orientations which thickness are 50nm. Put these samples in opening oven at constant temperature and heat to 350℃ for 10 hours in order to oxidize. After those process, we make some data for analysis of SEM , XRD , and TEM. The result is as following： 1. The quantity and length of the iron oxide nanorod are relate to thickness. The iron film is thin , the quantity of the iron oxide nanorod is less, and the length of the iron oxide nanorod is relatively short. The iron film is thick, the quantity of the iron oxide nanorod is more, and the length is relatively long. If the iron film is relatively thick , and when the low temperature is oxidized, it is apt to change nanorod into nanoblet. 2. The formation of the nanorod relates to the crystalline directions of the substrates and iron film. Almost there is no formation of nanorod on the substrate MgO(100) orientation,but there are some nanorod on the substrate MgO (110)、(111) orientation. It is among them with (111) peaks, and the length is the longest. Can be found out by the iron film crystalline grain direction on the substrate, the iron film Fe ( 100) peak grows of nanorod, and the iron film Fe (110 ), (211 ) are easy to grow nanorod. 3. During the process of iron turns into ?Fe2O3, the iron will be oxidized into other iron oxide first , mainly on Fe3O4. In the crystalline grain direction, it may be relatively easy to form ?Fe2O3 nanorod on the film Fe (110) orientation, and the formation of nanorod is easy to grow on ?Fe2O3 [110] direction and growth a ?Fe2O3 (110) surface.