A method for making a tunnel valve head with a flux guide, a tunnel valve
sensor having an isolated flux guide, and a magnetic storage system using
a tunnel valve sensor having an isolated flux guide is disclosed. The
tunnel valve sensors is created by forming a tunnel valve at a first
shield layer, the tunnel valve comprising a free layer distal to the
first shield layer, depositing a first insulation layer over the first
shield layer and around the tunnel valve, depositing a flux guide over
the first insulation layer and coupling to the tunnel valve at the free
layer, covering the flux guide with a second insulation layer and forming
a second shield layer over the second insulation, wherein the flux guide
and the free layer are physically isolated by the first and second
insulation layers to prevent current shunts therefrom. The structure
achieves physical connection between the flux guide and the free layer
and insulates the flux guide from the shields. By separating the flux
guide and the free layer from the shields, the shunting of current is
prevented.