Chen Yuan-Tsung, Chang Zu-Gao
J Nanosci Nanotechnol. 2017 Feb;17(2):1275-279. doi: 10.1166/jnn.2017.12577.
This study investigated the structure and thermal, electrical, optical, and adhesive properties of two magnetic CoFeB thin films with compositions of Co40Fe40B20 and Co60Fe20B20.The thin films were deposited on a glass substrate by using direct current (DC) magnetron sputtering at room temperature (RT) and ranged in thicknesses from 25 to 200 Å. X-ray diffraction (XRD) patterns indicated that the thin films were amorphous. The activation energy (Q) of the Co40Fe40B20 and Co60Fe20B20 thin films exhibited concave up and concave down trends, respectively. The critical thickness of the films was 75 Å. The 75-Å-thick Co60Fe20B20 thin film exhibited the highest Q value, indicating that transforming the amorphous structure into a crystalline structure is difficult. When the Co concentration ratio was increased, the stability of the amorphous state of CoFeB increased apparently. The 75-Å-thick Co60Fe20B20 thin film exhibited the highest resistivity, whereas the 75-Å-thick Co40Fe40B20 thin film exhibited the lowest resistivity. As the thickness of the Co40Fe40B20 and Co60Fe20B20 thin films was increased, the transmittance decreased and absorbance increased. The Co60Fe20B20 thin film exhibited a higher surface energy and stronger adhesion than did the Co40Fe40B20 thin film.
本研究调查了两种成分分别为Co40Fe40B20和Co60Fe20B20的磁性CoFeB薄膜的结构以及热学、电学、光学和粘附性能。这些薄膜在室温下通过直流磁控溅射沉积在玻璃基板上，厚度范围为25至200 Å。X射线衍射（XRD）图谱表明薄膜为非晶态。Co40Fe40B20和Co60Fe20B20薄膜的活化能（Q）分别呈现出上凹和下凹趋势。薄膜的临界厚度为75 Å。75 Å厚的Co60Fe20B20薄膜表现出最高的Q值，表明将非晶结构转变为晶体结构较为困难。当Co浓度比增加时，CoFeB非晶态的稳定性明显提高。75 Å厚的Co60Fe20B20薄膜具有最高的电阻率，而75 Å厚的Co40Fe40B20薄膜具有最低电阻率。随着Co40Fe40B20和Co60Fe20B20薄膜厚度增加，透光率降低，吸光度增加。Co60Fe20B20薄膜比Co40Fe40B20薄膜表现出更高的表面能和更强的粘附力。
