Fabrication process and layout for magnetic sensor arrays

摘要

A magnetic sensor includes a plurality of groups, each group comprising a plurality of magnetic tunnel junction (MTJ) devices having a plurality of conductors configured to couple the MTJ devices within one group in parallel and the groups in series enabling independent optimization of the material resistance area (RA) of the MTJ and setting total device resistance so that the total bridge resistance is not so high that Johnson noise becomes a signal limiting concern, and yet not so low that CMOS elements may diminish the read signal. Alternatively, the magnetic tunnel junction devices within each of at least two groups in series and the at least two groups in parallel resulting in the individual configuration of the electrical connection path and the magnetic reference direction of the reference layer, leading to independent optimization of both functions, and more freedom in device design and layout. The X and Y pitch of the sense elements are arranged such that the line segment that stabilizes, for example, the right side of one sense element; also stabilizes the left side of the adjacent sense element.

主权项

1. A method for manufacturing a magnetic sensor array, comprising:
forming a plurality of magnetic tunnel junction devices, wherein forming each magnetic tunnel junction device of the plurality of magnetic tunnel junction devices comprises:
forming and patterning a reference element, comprising:
forming an electrode; andforming a reference layer over the electrode;forming a tunnel barrier over the reference layer; andforming a plurality of sense elements over the tunnel barrier; forming a plurality of groups of magnetic tunnel junction devices, each group of magnetic tunnel junction devices comprising a plurality of the formed magnetic tunnel junction devices; and forming a respective conductor adjacent each of the formed magnetic tunnel junction devices, wherein the respective conductor and electrode of each magnetic tunnel junction device are configured to:
electrically couple (a) the magnetic tunnel junction devices within each group in parallel and (b) each of the groups in series; orelectrically couple (a) the magnetic tunnel junction devices within each of at least two groups in series and (b) the at least two groups in parallel.