Research TiNiCu Shape Memory Alloy Thin Films By Magnetron Sputtering

In this paper, it made TiNiCu shape memory alloy film on glass base usingRadioFrequency Magnetron Sputtering and systematically analyzed influence of sputterparameters to film quality. At the same time,this paper also optimized sputteringtechnology and systematically analyzed transformation temperature, transformationhysteresis and deformation of thin film after crystallization heat-treated. Throughpreparation films and sutdying structure property of films, the purpose is to obtain shapememory alloy film which has stronger driver ability and fast responding speed. And it ishoped to be an ideal material of microsystem driver.This paper used AFM and SEM to analyze surface topography and quality of thefilm. By XRD we can confirm and analyze composition of the film. Then I test andanalyze transformation temperature and transformation hysteresis. At last, obtain thefollowing results.(1) Because the sputtering yield of each element in the target material is different,the element composition proportion of the TiNiCu film obtained from the experimenthas a certain deviation of target. The sputtering yield of Ti is little. Therefore, in theprocess of experiment, we should not only put pure Cu slices on the TiNi target materialwith same atomic ratio, but also need to add a certain amount of pure Ti.(2) Observe the surface morphology of as-prepared TiNiCu film by AFM and SEM.Found that the surface roughness of the film increases with the sputtering power andsputtering pressure increased; the thickness of the film increased with the sputteringpower increased. Optimize the process parameters. The optimized sputtering processparameters as follows: sputtering pressure is0.6Pa, sputtering power is150w, thedistance of target material and substrate is100mm, the bottom vacuum is9x10-4Pa.After the optimization of sputtering parameters, the film’s quality is good. The atomicpercentage of each element is Ti: Ni, Cu=49:47:4.(3) Crystallization heat treatment was carried out on the as-prepared film. Themembrane is crystallized completely after1h vacuum annealing under650℃. TheDSC analysis result shows that Ms is331k, Mf is318k, As is329k, Af is340k, the is 11k, The film’s hysteresis of phase transformation decreased significantly, and is inthe martensite phase at room temperature.and when it reaches the temperature of phasetransformation points,the film changes in form.