Monolithic fabrication of millimeter-scale machines

Silicon-based MEMS techniques dominate sub-millimeter scale manufacturing, while a myriad of conventional methods exist to produce larger machines measured in centimeters and beyond. So-called mesoscale devices, existing between these length scales, remain difficult to manufacture. We present a versatile fabrication process, loosely based on printed circuit board manufacturing techniques, for creating monolithic, topologically complex, three-dimensional machines in parallel at the millimeter to centimeter scales. The fabrication of a 90 mg flapping wing robotic insect demonstrates the sophistication attainable by these techniques, which are expected to support device manufacturing on an industrial scale.