A TMR read head with improved voltage breakdown is formed by laying down the AP1 layer as two or more layers. Each AP1 sub-layer is exposed to a low energy plasma for a short time before the next layer is deposited. This results in a smooth surface, onto which to deposit the tunneling barrier layer,...http://www.google.de/patents/US7983011?utm_source=gb-gplus-sharePatent US7983011 - AP1 layer for TMR device
