The study of magnetism in Ge/Sb,Ge/Bi,Ge/SiO2 and Si/SiO2 systems

• Main Authors: En-yu Chao, 趙恩鈺
• Other Authors: Yung Liou
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/85220611019443775328

碩士 === 國立臺灣海洋大學 === 材料工程研究所 === 101 === In this study, we co-sputtered Ge with other materials (SiO2、Bi、Sb) on Si substrate using several working power combo, and then compared the magnetic properties and superficial appearance with multilayer samples prepared at the corresponding circumstance. From the topography, it shows that the SiO2、Ge、Si would formed smaller nano-spheres(average diameter&;lt;10nm) with size standard deviation about 0.2~0.3nm by the Log-normal distribution calculates. Obviously, the diameter distribution is fairly uniform. The Sb nano-spheres also have uniform size distribution, but the average diameter(about 15nm) is larger than ones of SiO2、Ge、Si. However, the Bi nano-spheres are not uniform, showing the wide average diameter range about 20~100 nm, which results in the following occurrence: when Bi is mixed with Ge by sputtering, the Ge particles are hard to be squeezed by big Bi particles. In the meantime there are still existing isolated Ge particles in the samples of higher Ge concentration. We can observe the magnetic properties at the room temperature because of the lack of large particles formed by linking. We understand that we can not prepare a continuous thin film by sputtering. Only we get is the crushing and discontinuous film. Therefore, we can assume that at very small thickness the multilayer will behave like particles with tiny diameter formed by co-sputtering, and then we can find out the magnetic properties at the room temperature.