Crystalline Structure, Mixed Valence States, and Magnetic Behavior in Single Crystalline Fe-Ni-O Thin Films

• Main Authors: WenLih Pan, 潘文立
• Other Authors: Gung Chern
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/22201701488253251244

碩士 === 國立中正大學 === 物理系 === 92 === In order to understand the structural transformation of the Fe - Ni - O mixture film formations, we use (MBE) molecular beam epitaxy to generate a series of Fe Ni O on MgO(001) substrate. During it’s developing process, we maintain its temperature at 250 0C and film in 1000  thickness. Regarding the film measurement, we use the x-ray diffraction instrument to measure the film’s crystal lattice constant transformation. We also use x-ray absorption spectroscopy to measure film’s electronic structure,and VSM to measure the film’s magnetic. Our laboratorial measurement research shows that mixture film Fe Ni O when X=0~0.71, its magnetic and oxide electric structure, is quite similar to Fe O ; both are spinel structure. However, when X=0.8~1,the film’s magnetic disappears and it’s oxide electric structures is also quite similar to NiO; both are rocksalt structure. Therefore, we would like to suppose that when X=0.71~0.8, the film’s structure transformed. Also, we may conclude the following assumption: the stability of crystal structure is related to the structure’s ion mixture valence and ion’s radius.