Electro-static micro-actuator for HDD tracking servo: compatibility with contact recording

Using an electrostatic micro-actuator for moving the slider body relative to suspension is a promising technique for achieving the extremely high track densities expected for future disk drives. To achieve, however, the small magnetic spacing necessary for these high recording densities, the recording head may have run in continuous contact with the disk surface by the time a micro-actuator technology needs to be implemented. So, a major concern is that the contact friction forces will cause an unacceptable amount of off-track motion due the flexible micro-actuator. This paper shows how minimal off-track motion of a contact slider with a microactuator can be achieved by using a suitably rough disk and a damping fluid in the micro-actuator.