Laser trapping technique in-air by using periodic structured surface substrate

For micro-system technology such as MEMS, techniques for handling micro-parts are the recent arisen issue. The laser trapping is one of the most expected techniques because it is non-contact method. However, the laser trapping in air condition has not matured especially in terms of method for the initial picking up phase, since the optical force by the laser trapping is relatively small compared to the adhesion forces. Therefore this study aims to develop the laser trapping method by reducing the adhesion forces, using a periodic structured substrate. The analysis shows that the van der Waals force, electrostatic force and capillary force can be decreased with the periodic structured substrate. The laser trapping experiments revealed that the substrate fabricated by the femto-second laser was effective for the laser trapping. It was found that the laser trapping on the 2-dimensional LIPSS was succeeded with a high possibility.