Deposition technology for thin film magnetic recording heads reader fabrication

Abstract

We review vacuum deposition technology for the fabrication of readers of thin film magnetic heads. We consider three different parts of the deposition, namely the magnetoresistive material, the longitudinal bias and metallization, and the gap dielectrics. The magnetoresistive materials are used to sense the magnetic flux from the media. Typical stacks (‘spin-valves’) are built of 10 or more individual layers with individual layer thicknesses down to less than 1 nm. We discuss the aspects of thickness and microstructure control. Magnetic stabilization and lead metallurgy is used to define the sensor laterally, both magnetically and electrically. We discuss the morphology and material property control. Gap dielectrics are thin Al 2O 3 films which provide dielectric separation between metallic layers. These films are deposited using ion beam deposition (IBD) and physical vapor deposition (PVD) techniques. We discuss the three respective applications from the point of view of device manufacturing in an industrial context.