Patent ID: 7252774
Filing Date: 2007-08-07
Classification: B82Y,C23F,H01F,H01L

Abstract:
1. A method of selectively patterning a magnetic film structure comprising the steps of: (a) providing a magnetic structure comprising at least one bottom magnetic film layer and at least one top magnetic film layer, wherein said at least one top and said at least one bottom magnetic film layers are separated by a tunnel barrier layer, and said at least one top magnetic film layer having a passivating layer located thereon; (b) forming a patterned resist on said passivating layer, wherein a portion of said passivating layer is exposed; (c) selectively etching said exposed portion of said passivating layer by a reactive-ion etching process to expose a portion of said at least one top magnetic film layer; and (d) selectively etching said exposed portion of said at least one top magnetic film layer by a wet etch process which includes an etchant solution comprising a surfactant inhibitor and at least one weakly adsorbing acid stopping on said tunnel barrier layer.