Research On Micro Control Of Flying Height For Hard Disk Heads

The demand for ever-greater storage capacity in magnetic recording continues to push the head-media spacing to be reduced to 6.5-7 nm in order to achieve a recording density of Tb/in2 and beyond. And the corresponding FH between the read-write head element and the disk surface will be merely 2.5-3 nm. In such a low flying-height condition, it becomes more important to keep the head-media spacing loss as small as possible during disk operations, for even the nanometer scale of FH loss will greatly impact the stability and reliability of the head-disk interface.According to the basic structure of the thermal flying height control slider, and combined with the head disc interface structure, we analyze the influence of the micro-heater on the heating stability of the flying height control slider. The finite element model of the thermal flying height control slider is given, and discusses various factors systematically, which impact the stability of the entire head disk interface, such as the size of micro-heaters, the input current of the heating coil of the micro heaters, and the distance between the micro- heater and the air bearing surface. Then we make a detailed analysis of kinds of factors, and analyze seriously how these factors affect the stability of the head disk system on the basis of the simulation. Finally, the heating coil of the micro-heater is studied.The simulation results show that: increasing the input current leads to the better heating performance, and reduces the flying height, but the thermal response time is not significantly reduced; reducing the distance between the micro-heater and the air bearing surface not only increases the performance of the heating system, but also increases the thermal response time; reducing the size of the micro-heater can effectively increase the performance of the heating system, but the thermal response time don't obviously decrease. The simulation results will provide a theoretical guide to the actual design of the flying height control slider.