Study on Interface Properties of Ti-Ni Shape Memory Films Sputtered on Si substrate

采用D. C.磁控溅射系统在不同的衬底温度下进行了几次沉积，范围从室温到658 K。在523 K以上沉积的薄膜是完全结晶的。横截面的TEM图像显示，生长的薄膜是一个直径为200 nm的柱状。选区电子衍射表明B2马氏体转变为B19'马氏体。采用直流磁控溅射法在硅（100）衬底上制备了Heusler型NiMnGa铁磁形状记忆合金（FMSMA）薄膜。当衬底温度高于623K或室温下沉积的NiMnGa FMSMA薄膜退火温度高于873K时，薄膜表现出良好的铁磁和形状记忆性能。薄膜为直径200nm的柱状生长。横截面TEM图像显示典型的马氏体变体，而选区电子衍射图案表明正交结构。的热机械光谱数据进行了测量与声学弹性计允许的阻尼，模量和悬臂位移作为温度的函数的同时测量。结果表明，在658K下沉积的薄膜和在室温下沉积并在873K退火的薄膜都发生了完全转变和大位移。

Ti-50at%Ni shape memory films with a thickness 1 μm were deposited on Si(100) substrate, using a D. C. magnetron sputtering system. Several depositions were made at different substrate temperatures, ranging from room temperature to 658 K. The films deposited over 523 K were completely crystalline. Cross-sectional TEM images revealed that the growth of the film is a 200nm diameter columnar. Selected area electron diffraction patterns show that B2 austenites transform to B19' martensites. Heusler-type NiMnGa ferromagnetic shape memory alloy (FMSMA) films were also deposited by DC magnetron sputtering, on silicone (100) cantilever-type substrates. NiMnGa FMSMA films show good ferromagnetic and shape memory properties if the substrate is heated above 623K or if films deposited at room temperature are annealed above 873K. The growth of the film is 200nm diameter columnar. Cross-sectional TEM images show typical martensitic variants while the selected area electron diffraction pattern suggests an orthorhombic structure. The thermo-mechanical spectroscopy data were measured with an acoustic elastometer permitting the simultaneous measurement of damping, modulus and the cantilever displacement as a function of temperature. It can be concluded that both of a full transition and large displacement develop in films deposited at 658K and in films deposited at room temperature and annealed at 873K.