Abstract
Mechanical properties of MEMS materials are increasingly important with the wide use of miniaturized systems. The study is focused on the mechanical characterization of electroplated Nickel (Ni) thin films used in microelectronic and micro-electromechanical systems (MEMS) devices. We provide the method of integration testing of mechanical properties of thin films. This method is suitable for thin films with large strain (> 5%) and can be applied to samples with different thicknesses.The Young’s modulus of an electroplated Nickel thin film has been investigated as a function of process variables, which are the plating temperature and current density. According to the cognition, we prepare thirteen batch of specimens in different plating temperatures and current densities. With a variable deposition thickness from 1.4 μm to 11.6 μm, tensile specimens of Ni thin film, with a gauge section 1000 μm wide and 4000 μm long were tested. And the diameters of bulge specimens are 500 and 750 μm. The measured Young’s modulus of 4.73 μm thick Ni thin film is about 39.72 GPa by tensile test, 198.78 GPa by bulge test and 263.48 GPa by nanoindentation test at 40℃, 0.22 ASD. In the same condition, the measured yield strength and breaking strength is 964.52 MPa and 1346.93 MPa, respectively.