Contactless electrostatic handling of microcomponents

Microdevices are every day becoming more sophisticated and flexible. Common manufacturing techniques based on semiconductor technology do not fully meet the requirements brought up by the development of new applications or the necessity of increased performances in actual systems. In order to obtain three-dimensional structures with high mechanical properties, new manufacturing approaches based on the exploitation of different materials are necessary and the assembly of these microparts becomes a key issue to solve. In the assembly process, because of the low mass of the microcomponents, adhesive forces (surface tension, van der Waals and electrostatic attraction) cause the component to stick, with the gripper making the releasing phase very complex. Therefore microassembly requires new handling techniques such as, for example, electrostatic contactless handling, which appears to be very promising. Through a comparative analysis between theoretical results and simulations, the electrostatic forces on which the alignment and movement of microparts is based have been estimated and a demonstrative device has been designed and tested. In this paper electrostatic contactless handling is discussed, the developed prototype is presented and the feasibility of the transportation and positioning of miniand micro-objects (as predicted by theory) is demonstrated through a set of experiments