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As a kind of amorphous alloy, metallic glasses are suitable materials for micromachines because their size effect is considered to be absent. However, neither the fabrication process nor the physical properties of thin-film metallic glasses (TFMGs) have yet been examined. In this paper, Pd-based (Pd76Cu7Si17, atomic composition) TFMG was first fabricated by an RF-magnetron sputtering method. The existence of a supercooled liquid region (SCLR) and the thermal stability with respect to crystallization were measured by a differential scanning calorimeter (DSC). The existence of the SCLR was reconfirmed by a thermomechanical analyzer (TMA). The hardness of Pd-TFMG was measured by a mechanical testing machine for micro-sized specimens (MMT2000), while the Young's modulus was measured by a MMT2000 in the bending mode as well as by a TMA in the tensile mode. The resistivity of Pd-TFMG was tested by the four-point probe method. Finally, the influences of deposition conditions were discussed and the physical properties of TFMG were compared with those of Pd-based bulk metallic glass.

A new MEMS conical spring actuator array is proposed. Previously, we have developed conical spring microactuators having a long stroke (180 m) in the out-of-plane direction.However, the maximum output force and the packing density were not satisfactory. In the present paper, mechanical and electrical models of a conical spring are described for the calculation of the maximum output force and the driving voltage. Geometrical parameters were optimized using these models and a new geometry for the actuator was derived. The new geometry incorporates a wider and thicker spring that increased the maximum output force from 0.087 mN up to 0.83 mN. The packing density was increased up to 1 actuator mm 2 using an additional interconnect layer. In addition, the driving voltage was decreased using a thinner insulating layer. The use of an ac drive prevented the sticking of the actuator during operation. A detailed investigation of the ac drive was also performed.[1304]Index Terms-AC drive, conical spring microactuator, out-ofplane, thin film metallic glass, three-dimensional (3-D) shape.

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Cu-based micro-temperature detectors were fabricated using femtosecond laser reduction of CuO nanoparticles. Cu-based microstructures were directly created by laser scanning on a CuO nanoparticle solution film. Cu-rich and Cu2O-rich microstructures were selectively formed to electrically connect two Cu thin-film electrodes for use in temperature detectors. Cu-rich and Cu2O-rich micro-temperature detectors were fabricated at scanning speeds of 500 and 1000 µm/s, respectively, at a pulse energy of 1.2 nJ. The temperature coefficient of resistance values of the Cu-rich and Cu2O-rich microstructures were positive and negative, respectively; these temperature behaviors are typical of metal and semiconductor materials, respectively.