【作者】 姜华；

【导师】 周白杨；

【作者基本信息】 福州大学 ， 材料加工工程， 2006， 硕士

【摘要】 超磁致伸缩薄膜是用于制作微机电系统驱动元件的新型功能材料,它具有强的磁致伸缩效应,高机电耦合系数与响应速度,低磁滞与低涡流损耗以及非接触式驱动等优点,在智能结构材料方面具有重要的地位和很好的应用前景。本文采用离子束溅射法（IBS）在锡青铜（QSn）、铍青铜（QBe）、盖玻片（Glass）和单晶硅抛光片（Si）基片上溅射沉积Sm-Fe薄膜,通过SEM、XRD以及VSM等现代测试手段分析Sm-Fe薄膜的表面形貌、成分、组织结构和磁性能; 通过改变基片状态、工艺参数以及真空热处理等手段改变薄膜的应力、形貌与组织结构,以达到改善Sm-Fe薄膜磁致伸缩性能的目的,特别是提高低场下的磁伸性能; 针对DWS型电容位移测量仪的校准问题,设计组装了一套校准装置用于位移测量仪的校准和标定; 对于基片和薄膜弹性模量的问题,采用悬臂量-加载法和纳米压痕仪进行测量。实验结果表明: 1.采用两种手段（微量天平法和轮廓仪法）得到的两种膜厚（质量膜厚和形状膜厚）相差不大,彼此偏差在8%以内。离子束溅射沉积在水平溅射方向上的沉积速率比在垂直溅射方向上的沉积速率变化大。Sm-Fe薄膜的沉积速率在溅射时间为4h时到达最大,达到0.0414nm/s。2.在不同衬底上沉积的Sm-Fe薄膜表面形貌差异很大。溅射方位不同（42.5o～57.5o）和衬底不同对Sm-Fe薄膜的成分的影响很小。制备态和200℃、250℃退火态的Sm-Fe薄膜都是非晶态结构,300℃热处理开始出现晶化。3.在盖玻片、锡青铜和铍青铜衬底上,利用离子溅射法沉积Sm-Fe薄膜产生的应力都是压应力。溅射角度对Sm-Fe薄膜应力的影响很小。4.制备态Sm-Fe薄膜的易磁化轴平行于膜面,且接近于Y方向（平行样品短轴方向）。经热处理后,Sm-Fe薄膜平行膜面的磁各向异性已不明显,且退火态Sm-Fe薄膜/ QSn衬底的软磁性能比制备态样品有显著提高。200℃退火态Sm-Fe薄膜的饱和磁化强度Ms最大。5.对于制备态Sm-Fe薄膜,低场下的磁伸性能都较低,可通过改变薄膜的表面形貌（使衬底的表面划痕平行于短轴）或使薄膜处于适当的压应力状态来提高其饱和磁伸系数。对薄膜进行200℃热处理,会使Sm-Fe薄膜具有最大的饱和磁伸系数(398×10^-6); 250℃热处理可使Sm-Fe薄膜具有最好的低场磁伸性能(0.02T时达到108.5×10^-6)。更多还原

【Abstract】 Giant magnetostrictive thin films are very promising for microactuator elements like cantilevers or membranes as they combine high energy output, high frequency and remote control operation, simple actuator lay-out, and low process temperatures during fabrication. In this paper, Sm-Fe GMFs were fabricated by IBS on bronze, glass and si substrates. The surface profiles, composition, microstructure and magnetic property of Sm-Fe GMFs were determined and investigated by using SEM, XRD and VSM. By altering the substrate state, processing parameters and annealing treatment, the change of stress and structure in the thin film were obtained, which resulted in improving the magnetostriction of Sm-Fe GMFs. By using a self-constructed equipment, the DWS type Capacitance-displacement micrometer was calibrated accurately. The elastic modulus of substrate and films were determined by cantilever-load methods and nanoindentation methods. The results were shown as follows: 1. The thickness of thin films were measured by two methods. The results of two measuring methods are near. The deposited rate of Sm-Fe GMFs is the largest when deposited time is 4 hours . 2. The surfaces of Sm-Fe GMFs is obvious different on the different substrates. Sm-Fe GMFs of as-deposited and annealed at 200℃ and 300℃ exhibit amorphous structure. When it was annealed at 300℃ for 1 h, crystal structure appeared. 3. Compressive press is produced when Sm-Fe GMFs were fabricated by IBS on bronze and glass substrates. The stress of Sm-Fe thin films are near in different sputtering angles during 42.5o～57.5o. 4. The as-deposited film and the heat-treated film showed anisotropic magnetization with the easy axis parallel to the film surface. And the easy axis of the as-deposited film parallel to the orientation of the short side of the substrate. After heat treatment, the soft magnetic properties of Sm-Fe GMFs increased obviously. The thin film treated at 200℃ showed the largest saturation magnetization Ms. 5. The low-field magnetostriction coefficient of the as-deposited film is too small. Compressive press applied to the films makes its saturation magnetostriction coefficient increased slightly. After heat treatment, Sm-Fe GMFs shows an improved low-field magnetostriction properties as the magnetostrictive saturation field is reduced . The thin film treated at 200℃ has the largest saturation magnetostriction coefficientλs attained 398×10^-6. After treatment at 250℃ , the Sm-Fe films showed the best low-field magnetostriction attained 108.5×10^-6 at 0.02T.更多还原