A new wear measurement technique for pseudo-contact magnetic recording heads

Pseudo-Contact magnetic recording sliders remain in contact with the disk even at operating speeds. The continuous contact can cause wear of the interface that might eventually lead to failure of the drive. In order to evaluate the long term reliability, precise measurements of the slider wear are necessary. In this paper, a new method of measuring the depth and location of wear on the slider is described. Fiduciary marks are created on the slider air-bearing surface using a focused ion beam (FIB). These FIB marks are characterized using an AFM before and after a wear test. The technique allows measurement of wear depths within an accuracy of ±1 nm. Some additional techniques for detecting slider wear are described