Multi-step sequential batch self-assembly of three-dimensional micro-structures using magnetic field

We have developed a process for multistep sequential batch self assembly of complex three dimensional ferromagnetic microstructures. The process uses the magnetic torque generated by an external magnetic field perpendicular to the substrate to lift hinged structures. In our previous study, we found that a nondimensional factor that depends on its shape determines the sensitivity of the micro hinged structures to a magnetic field. This factor can be used as a criterion in designing a process for sequential batch self assembly, because the factor indicates the differences in the sensitivity. In this study, we designed multistep sequential assembly by using the nondimensional factor. Four step sequential batch assembly was demonstrated using this method.