Fabrication and Recording Study of All-Metal Dual-Spin-Valve CPP Read Heads

Abstract

All-metallic giant magnetoresistive (GMR) sensors in a current-perpendicular-to-plane (CPP) geometry are attractive candidates for future high-density recording sensors due to their low intrinsic resistance. With increasing recording density the cross-sectional area of CPP sensors (such as TMR or GMR sensors) must also decrease, resulting in a rapid increase in sensor impedance unless the RA product of the sensor stack also decreases. Thus, as recording densities increase above 300 Gb/in2, and sensor sizes decrease below 50nm, low-resistance CPP-GMR sensors become of greater interest to minimize impedance, reduce noise and improve the bandwidth characteristics of the read head. Here we present results on the magnetotransport properties, fabrication, and performance of all-metal CPP-GMR shielded read heads with ultra-narrow physical widths between 40 and 60 nm.