A B S T R A C T This paper describes the mechanical characteristics of microscale single crystal silicon (SCS) and UV-LIGA nickel (Ni) films used for microelectromechanical systems (MEMS). A compact tensile tester, operated in an atomic force microscope (AFM), was developed for accurate evaluation of Young's modulus, tensile strain and tensile strength of microscale SCS and UV-LIGA Ni specimens. SCS specimens with nominal dimensions of 20 µm in thickness, 50 µm in width and 600 µm in length were prepared by a conventional photolithography and etching process. UV-LIGA Ni specimens, with a thickness of 15 µm, a width of 50 µm and a length of 600 µm in nominal dimensions, were also fabricated by electroplating using a UV thick photoresist mould. All specimens have line patterns on their specimen gauge section to measure axial elongation under tensile loading. The SCS specimens showed a linear stress-strain response and fractured in a brittle manner, whereas the UV-LIGA Ni specimens showed elastic-inelastic deformation behaviour. Young's modulus of SCS and UV-LIGA Ni specimens obtained from tensile tests averaged 169.2 GPa and 183.6 GPa, respectively, close to those of bulk materials. However, the tensile strength of both materials showed a larger value than the bulk materials: 1.47 GPa for the SCS and 0.98 GPa for the Ni specimens. Yield stress and breaking elongation of UV-LIGA Ni specimens were also quite different from those of the bulk Ni because of the specimen size effect on inelastic properties.

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SmCo film magnet has been synthesized on a heated substrate by means of rf sputtering. In Sm1−xCox (0.6≤x≤0.98) films the saturation magnetization simply decreases with the increase in Sm content, while the other magnetic properties strongly depend on the crystalline phases. The film with 1 μm in thickness and x∼0.8 mainly consists of SmCo5 phase, which exhibits in-plane anisotropy. The films with the easy axis perpendicular to the film surface are obtained in the composition around x=0.75. It is the mixture of amorphous and crystalline SmCo3 phases.