CPP Device with a Plurality of Metal Oxide Templates in a Confining Current Path (CCP) Spacer

摘要

A novel CCP scheme is disclosed for a CPP-GMR sensor in which an amorphous metal/alloy layer such as Hf is inserted between a lower Cu spacer and an oxidizable layer such as Al, Mg, or AlCu prior to performing a pre-ion treatment (PIT) and ion assisted oxidation (IAO) to transform the amorphous layer into a first metal oxide template and the oxidizable layer into a second metal oxide template both having Cu metal paths therein. The amorphous layer promotes smoothness and smaller grain size in the oxidizable layer to minimize variations in the metal paths and thereby improves dR/R, R, and dR uniformity by 50% or more. A thin Cu layer may be inserted between the amorphous layer and oxidizable layer before the PIT and IAO processes are performed.

主权项

1. A method of forming a confining current path (CCP) spacer in a magnetic sensor structure, comprising:
(a) forming a first copper layer on a ferromagnetic layer; (b) forming an amorphous layer made of metal, alloy, or metal oxide on said first Cu layer; (c) forming a second copper layer with a thickness of 0 to 6 Angstroms on the amorphous layer; (d) depositing an oxidizable layer on the second copper layer; (e) performing a pre-ion treatment (PIT) followed by an ion-assisted oxidation (IAO) to transform the amorphous layer into a first metal oxide template having segregated Cu metal paths therein, and to transform the oxidizable layer into a second metal oxide template having segregated Cu metal paths formed therein; and (f) depositing a third Cu layer on the second metal oxide template.