Patent ID: 8339841

Claim:
A magnetoresistive element comprising: a lower electrode on an insulating layer on a semiconductor substrate; a first ferromagnetic layer on the lower electrode; a first tunnel barrier layer on the first ferromagnetic layer; a second ferromagnetic layer on the first tunnel barrier layer; an upper electrode on the second ferromagnetic layer; an insulating first protective film on a side surface of the lower electrode, formed by a first deposition; and a second protective film, formed by a second deposition that is distinct from the first deposition, on side surfaces of the first and second ferromagnetic layers, on a side surface of the first tunnel barrier layer, and on the first protective film, a thickness of the second protective film being different from a thickness of the first protective film, wherein the upper electrode has a substantially hexagonal cross-sectional shape, a portion of the upper electrode having a maximum dimension in a first direction is located below a top surface of the upper electrode and above a bottom surface of the upper electrode, the first direction being horizontal relative to a surface of the semiconductor substrate, and the maximum dimension in the first direction of the upper electrode is larger than a maximum dimension in the first direction of the first tunnel barrier layer.