A novel fast and low cost replication technology for high-aspect-ratio magnetic microstructures

This paper describes a new fabrication technology for high aspect ratio magnetic microstructures. These microstructures are made of composite magnetic materials. In this new technology, a master mold was made using photolithography and the mixture of magnetic particles and polymer was used in micro-molding process. The microstructures were then thermally cured at a temperature lower than 80 °C. To demonstrate the feasibility of using the technology in making magnetic microstructures, both hard magnetic and soft magnetic particles were tried in our experiments. The magnetic particle sizes ranged from 2.3 to 44 μm, which sets the limitations in feature sizes achievable for the magnetic microstructures. Different weight ratios were tried, the maximum weight ratio between the magnetic particle and the polymer was over 2:1. For both wall and trench microstructures, the maximum aspect ratio was found to be over 10, which demonstrates its great potential for micro-fabrication applications.