Magnetic and Electrostatic Hybrid Microstructures for Microfluidic and Microrobotic Applications

The application of magnetic and electrostatic microscale devices and sensors is ever increasing as the length scales observed in many research areas decrease. The contact-free nature of these actuation methods makes them attractive for many devices, however, the integration of materials responsive to multiple control methods in microscale systems is currently difficult to achieve and not well examined. In this work, we present characterized microfabrication methods for both uniform magnetic composite microstructures and uniform electrostatic composite microstructures, as well as the creation of novel micromagnet designs with unique geometries and controllable heterogeneity of magnetic properties. Our current research additionally involves the fabrication of hybrid microstructures that can be independently actuated with either magnetic or electrostatic properties using UV photolithographic and thermal vapor deposition methods. These microstructures can be fabricated with relatively inexpensive materials and are easy to integrate into typical microfabrication processes. This research also involves the demonstration of these hybrid structures as functional microrobotic systems. Because the hybrid microstructures are created to be independently responsive to both magnetic and electrostatic actuation forces, one mode of actuation can be used to provide controlled motion of these free-standing microrobots, while the other can be used to change the conformation of the structures or selectively immobilize them. This dual-control method can be used to provide useful interaction of the robots with their microenvironment or make it possible to individually manipulate single robots within a larger swarm