A 2-D PVDF force sensing system for micro-manipulation and micro-assembly

Abstract

Despite the enormous research efforts in creating new applications with MEMS, the research efforts at the backend such as packaging and assembly are relatively limited. One reason for this is the level of difficulty involved. One fundamental challenge lies in the fact that at micro-scale, micro mechanical structures are fragile and easy to break - they typically will break at the micro-Newton (μN or 10-6N) force range, which is a range that cannot be felt by human operators. In this paper, we will present our ongoing development of a polyvinylidence fluoride (PVDF) multi-direction micro-force sensing system that can be potentially used for force-reflective manipulation of micro-mechanical devices or micro-organisms over remote distances. Thus far, we have successfully demonstrated 1D and 2D sensing systems that are able to sense force information when a micro-manipulation probe-tip is used to lift a micro mass supported by 2μm×30μm×200μm polysilicon beams. Hence, we have shown that force detection in the 50μN range is possible with PVDF sensors integrated with commercial micro-manipulation probe-tips. We believe this project will eventually make a great impact to the globalization of MEMS foundries because it will allow global users to micro-assemble and micro-manipulate surface micromachined devices from their laboratories, and therefore, reduce the time from design to production significantly.