A hard-disk drive tracking servo microactuator driven by PZT with stroke amplification mechanism

A new type of moving-slider microactuator for high track pitch HDD was investigated. The new microactuator uses PZT ceramic as a source of actuation. Since PZT can generate high force, the microactuator can use a very stiff spring while achieving the required stroke. A microactuator has a stroke amplification mechanism, so that the small stroke generated by PZT ceramic is amplified. In order to take advantage of superior material property of bulk PZT ceramic, a "hybrid" approach was employed: bulk PZT ceramic and microactuator structure is separately processed/fabricated, then, these two are assembled at the final step of fabrication process. A microactuator and PZT ceramic was successfully fabricated, assembled, and tested. Frequency response measurement showed excellent performance of this microactuator.