Process for producing a magnetic read - write head and head obtained by this process

Claim 1

A process for producing a magnetic read-write head, comprising the steps of: depositing a first magnetic material film on a support, etching a groove in said first magnetic film, said groove being shaped like a figure eight with two loops having in common a rectilinear central portion, the magnetic film being preserved within said two loops and forms there two central pole pieces separated by a central channel corresponding to the central portion of the figure eight, filling the groove with an electrically insulating material, etching in the insulating material a notch forming a double groove wound respectively around the two central pole pieces, depositing a conductive coating at the bottom of the double groove and then filling the double groove with a first electrically insulating material, depositing a second insulating material layer on the two central pole pieces and on the first electrically insulating material, etching in said layer a step having a side substantially perpendicular to the surface of the central portion of the figure eight but which is slightly off-center with respect thereto, depositing an amagnetic material film on the thus etched step, anisotropic etching said amagnetic film so as to only leave a wall of said amagnetic film perpendicular to the plane of the films and constituted by that part of the amagnetic film depositing on the side of the step, depositing a second magnetic material film forming a boss covering the wall, depositing a protective coating on said second magnetic material film and covering the boss and cutting the protective coating of the second magnetic material film and the amagnetic wall, along a common horizontal plane substantially parallel to said first magnetic film, pole pieces are separated by an air gap.