Patent ID: 8590139

Claim:
A method for patterning and electrically contacting a magnetic stack, comprising: providing a magnetic stack comprising a magnetic layer sub-stack comprising at least one magnetic layer and a bottom conductive electrode and a top conductive electrode electrically connecting the magnetic layer sub-stack at opposite sides thereof, wherein the magnetic layer comprises a magnetic material; providing a sacrificial pillar on top of the magnetic stack, the sacrificial pillar having an undercut with respect to an overlying second sacrificial material and a sloped foot with increasing cross-sectional dimension towards the magnetic stack; using the sacrificial pillar for patterning the magnetic stack by patterning the top conductive electrode and the magnetic layer to create a magnetic pillar, whereby a part of the magnetic material is redeposited onto sloped sidewalls of a patterned first sacrificial layer but not onto the magnetic layer; depositing an insulating layer around the sacrificial pillar; planarizing the insulating layer below a level of the second sacrificial material, whereby a portion of the sacrificial pillar is left; selectively removing the sacrificial pillar, whereby a contact hole towards the patterned magnetic stack is created in the insulating layer; and filling the contact hole with an electrically conductive material.