Batch fabricated silicon electrostatic micropositioner for dual stage actuation

Hard Disk Drives (HDD) are the most widely used data-storage medium. The Track Per Inch (TPI) limit is related to mechanical resonances of the positioning arm and to low frequency bearing effect. A secondary actuator must be able to position precisely with higher bandwidth the Read/Write (RW) head with respect to the magnetic track with any interference with the magnetic data recorded on the disk. MEMS technology allows the fabrication of such electrostatic microactuator for the secondary stage in the HDD. The paper presents the basics requirements for the secondary actuator for the HDD as well as the process developed to fulfill those. Accurate calculation and FEM simulation are required to lead to high performance and robust design. After the built a deep experimental analysis is ducted to confirm and refine design parameters.