Effect of Head–Disk Interface Biasing and Relative Humidity on Wear of Thermal Flying Height Control Sliders

In this investigation, we examine wear of thermal flying height control sliders as a function of DC bias voltage across the head–disk interface, relative humidity, and lubricant type. Wear tests were conducted using two different experimental setups, a load/unload tester, and a spin-stand tester with relative humidity control. Head wear was determined by measuring the change in the heater touch-down power (ΔTDP) before and after wear testing. After wear testing, selected recording heads were examined using atomic force microscopy and time of flight secondary ion mass spectrometry to investigate wear and deposit formation in the read/write region. Our results show that the polarity of the head–disk interface bias voltage and the relative humidity influence deposit formation and wear in the read/write region of recording heads.