Characterization of sputtered TiNi shape memory alloy thin films

The sputtering of TiNi polycrystalline alloys without and with a titanium m esh has been investigated for the development of shape memory alloy (SMA) m icro-actuators. The thickness and composition distributions of TiNi thin fi lms have been determined by Rutherford backscattering spectroscopy (RBS). T he composition of sputtered films was demonstrated to depend on the density of the titanium mesh and the distance from the target center, thus enablin g easy fabrication of high and low temperature SMA actuators. The transitio n temperatures and resistivity have been measured with respect to the compo sition.