Optimization of thermal fly-height control slider geometry for Tbit/in² recording

Magnetic storage advances including thermal fly-height control (TFC) technology were able to reduce the clearance between the read/write elements of the slider and the disk surface to increase the recording density of hard disk drives without compromising the stability of the head–disk interface (HDI). Sliders employing TFC technology are designed for flying recording and can yield clearances of few nanometers. However, it is estimated that TFC technology alone cannot provide the even smaller clearances necessary to achieve Tbit/in² recording densities primarily due to the presence of instability-inducing vibrations at the HDI. In this work we perform optimization of the geometry of TFC technology sliders to achieve extremely high-density recording. We propose a flyability parameter coupled with a dynamic, contact mechanics-based friction model of the HDI that accounts for TFC geometry and its influence on the HDI dynamics. Optimization results are analyzed and an operating actuation range is identified that can yield Tbit/in² recording densities with Angstrom-level clearance and minimized vibrations while also accounting for manufacturing and operational tolerances. This allows for light (lubricant) contact or ‘surfing’ recording. The proposed methodology can be used to reduce wear at the interface and investigate the feasibility of contact recoding.