A Novel Metrology Technique to Capture the Flying Dynamics of Air Bearing Slider with and Without Induced Contact

Abstract

Characterization of slider motion induced by contact is becoming a critical aspect of developing advanced head-disc interfaces. While vertical and sway (side-to-side) motions induced by contact have been studied, very little is known about down-track motions. Moreover, we also simultaneously measure the pitch and roll of the slider during this contact event. We have employed three separate and independent Laser Doppler Vibrometers to measure slider movement in three orthogonal directions simultaneously while a Position Sensitive Detect (PSD) is used to measure the pitch and roll of the slider during the contact event. Head-disc contact resulting from writer-current induced pole tip protrusion is studied as a function of writer current and writer frequency as well as disk speed are studied. In addition, a depiction of the vertical, down-track, and off-track position changes by plotting the position of the slider in real space coordinates to help visualize more completely how the slider moves in space. These trajectories depict the periodic, elliptical path the slider takes and identify how the paths change with contact.