High-Performance On-Chip Hot-Pressed NdFeB Hard Magnets for MEMS Applications

In order to advance the potential of thick on-chip hard magnets for the micro-electro-mechanical system (MEMS), we investigate a new silicon molding technique to fabricate dry-packed NdFeB magnets, including a silicon compression tool, which enables the pressing step during silicon-compatible processing. This process delivers samples with a remanence of 0.42 T and an energy product of 38 kJ/m
³
. Further studies of metal molding show that, for wax-bonding powder-based NdFeB magnets, the optimum fabrication condition is 300 °C and 425 MPa, giving a remanence of 0.54 T and an energy product of 61.7 kJ/m
³
.