A concept of soft-handing tweezers using comb-drive actuator

This paper describes a concept of the micro tweezers using comb-drive actuator which handles a minute material softly. The concrete purpose is holding DNA, a cell, etc. softly. We formulated the technique of detecting the mechanical characteristic of the comb-drive actuator widely used as a micromachined actuator by electric admittance measurement. By using this, it is detectable that the tweezers arm which is carrying out resonance vibration contacted the cell in solution. Since attenuation of the amplitude can be grasped by admittance change, the monitoring of the strength of handling may be able to be carried out. The resonance characteristic can be observed though the viscosity resistance becomes large in a solution and the amplitude becomes small compared with air. Using this concept we evaluated mechanical properties of a fabricated comb-drive actuator and confirmed its practical usefulness for characterization of soft-handling tweezers