Probe manipulation of fine particles has been investigated in our laboratory. The feature of our system is that wide range of voltage, 0-10kV, can be applied between the probe and the substrate. In this method, we can pick up a fine particle at the tip of the probe, carry, place and weld the particle at a predetermined point on the substrate by controlling the applied voltage to the probe. When the particle is picked up, 10-50V is applied. And 2-10kV is applied for the welding. Breaking shear stress of welded particles is measured as follows. A sheet spring, where the strain gauges are stuck, is prepared. One end of the sheet spring is held, and moved to push off the welded particle by the free end. The shear stress is calculated from the output of the strain gauges. The breaking shear stress is 44-71MPa for gold particles welded on a gold substrate. Self- sustaining characters, 'NRIM', are formed from gold particles of 40micrometers as an example of microstructure. Preliminary experiments for the application to the ball grid array are carried out. We also fabricated a slant tower of magnetostrictive particles. It will be used as a micro- actuator in the alternative magnetic field.
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