薄膜厚度與組成對磁光薄膜GdFeCo與TbFeCo性質之影響

• Main Authors: Tzo-Yin Chiu, 邱子茵
• Other Authors: Chih-Huang Lai
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/35072597609377746054

碩士 === 國立清華大學 === 材料科學工程學系 === 89 === This thesis focuses on “ How the thickness and composition variations of sputtered magneto-optic thin-film “Gdx(Fe80Co20)1-x and Tbx(Fe80Co20)1-x affect the magnetic properties, such as coercivity、saturated magnetization、perpendicular anisotropy constant and exchanging coupling constant etc.. The relation between these magnetic properties, like perpendicular anisotropy constant and saturated magnetization, perpendicular anisotropy constant and exchanging coupling constant etc., are also systematically investigated. In addition, the dependence of the domain structures on the thickness and composition of the thin films was clarified by using magnetic force microscope. The experimental results indicate that the tendency of magnetic properties toward increasing thickness for the TM-rich media is opposite to that for the RE-rich. This difference between TM-rich and RE-rich media is mainly due to the exchange-couple constants of RE atoms and TM atoms are not equal to each other at different thin film thickness. And the correlations of magnetic properties versus composition can be divided into two parts by setting the compensation composition point being the dividing point. For example , the saturated magnetization is the smallest at compensation composition point compared to other composition. As the composition get leaving this compensation point, the saturated magnetization will get increasing. Furthermore, the observations of the domain structures by using MFM exhibit that the variation of thin-film thickness affects the domain structure significantly because the thicker thin film produce more incoherent spots, as the defects during the domain reversal process. It further results in the smaller domain structure in the thicker film than that in the thinner.