A modular microvalve suitable for lab on a foil: Manufacturing and assembly concepts

Abstract

Graphical abstractDisplay Omitted Highlights? A modular layered microvalve with: active, membrane and passive layer is presented. ? It employs phase change actuation using paraffin and is structured in plastic foils. ? Component layers are distinct and are structured only from one side. ? Design modularity and assembly concepts are explored by dispensing paraffin. ? The robust design can tolerate variations in dispensed paraffin volume. Systems-in-foil are receiving a lot of attention because of their robustness, multi-functionality, and reel-to-reel manufacturability. Such systems are typically less constrained with respect to their lateral dimensions but they are typically very thin. The integration of micro-fluidic functionalities in such systems made on flexible polymeric foil substrates offers a new concept named lab-on-foil. Up to now these devices are constructed of one material and they only have passive fluidic structures. However, systems allow more elaborate functions if active elements are incorporated. To achieve this, passive components (channels or other small fluid containers, sieves) and active fluidic components (valves, pumps, mixers, active filters, sensors) have to be integrated in a single system. A system has been designed in view of the manufacturing processes for a successful transition into mass production. Here we present the manufacturing and assembly of such a novel polymeric microvalve covering an areal space of a 1 mm2 employing thermal phase change actuation. Individual functional components: actuator foil, interfacing membrane, and fluidic channel foil are distinct and structured only in their respective layers. The valve is assembled by laminating the functional layers. Paraffin which forms the actuating material is filled into an actuation cavity using dispensing methods. It was proven by performance analysis that the robust design can tolerate variations in dispensed paraffin volume.