SPACER LAYER FOR MAGNETORESISTIVE MEMORY

摘要

A bottom pinned perpendicular magnetic tunnel junction (pMTJ) with high TMR which can withstand high temperature back-end-of-line (BEOL) processing is disclosed. The pMTJ includes a composite spacer layer between a SAF layer and a reference layer of the fixed magnetic layer of the pMTJ. The composite spacer layer includes a first non-magnetic (NM) spacer layer, a magnetic (M) spacer layer disposed over the first NM spacer layer and a second NM spacer layer disposed over the M layer. The M layer is a magnetically continuous amorphous layer, which provides a good template for the reference layer.

主权项

1. A method of forming a device comprising:
providing a substrate comprising circuit component formed on a substrate surface; performing back-end-of-line (BEOL) processing to form level dielectric (ILD) layer over the substrate, wherein the ILD layer comprises a plurality of ILD levels; and forming a magnetic tunneling junction (MTJ) stack in between adjacent ILD levels of the upper ILD layer, wherein the MTJ stack comprises
a magnetic fixed layer, the magnetic fixed layer comprises
a synthetic antiferromagnetic (SAF) layer,a composite spacer layer disposed on the SAF layer, the composite spacer layer comprises
a first non-magnetic (NM) spacer layer,a magnetic (M) spacer layer disposed over the first NM spacer layer, anda second NM spacer layer disposed over the M layer, anda reference layer disposed over the composite spacer layer,a tunneling barrier layer disposed over the magnetic fixed layer, anda magnetic free layer disposed over the tunneling barrier layer.