Methods for MTJ patterning for a MTJ device are provided. For example, a method includes (a) providing an MTJ device comprising a substrate comprising a plurality of bottom electrodes, a MTJ layer disposed on the substrate, and a plurality of pillars disposed on the MTJ layer and over the plurality of bottom electrodes, wherein the plurality of pillars comprise a metal layer and a hard mask layer disposed on the metal layer, (b) conducting a first ion beam etching of the MTJ device; (c) rotating the MTJ device by 90 degrees in a clockwise or a counter clockwise direction about an axis perpendicular to a top surface of the MTJ device from a starting position; (d) conducting a second ion beam etching of the MTJ device; and (e) repeating steps (c) and (d).

A method MT includes etching a wafer W using plasma generated in a processing container. The etching includes a process of inclining and rotating a holding structure holding the wafer W during execution of the etching and the process successively creating a plurality of inclined rotation states RT(, t) with respect to the holding structure. In the inclined rotation states, the wafer W is rotated about a central axis of the wafer W over a predetermined process time while maintaining a state where the central axis is inclined with respect to a reference axis of the processing container which is in the same plane as the central axis. A combination of a value of an inclination angle AN of the central axis with respect to the reference axis and the process time t differs for each of the plurality of inclined rotation states.

In a method of manufacturing a semiconductor device, a magnetic random access memory (MRAM) cell structure is formed. The MRAM cell structure includes a bottom electrode, a magnetic tunnel junction (MTJ) stack and a top electrode. A first insulating cover layer is formed over the MRAM cell structure. A second insulating cover layer is formed over the first insulating cover layer. An interlayer dielectric (ILD) layer is formed. A contact opening in the ILD layer is formed, thereby exposing the second insulating cover layer. A part of the second insulating cover layer and a part of the first insulating cover layer are removed, thereby exposing the top electrode. A conductive layer is formed in the opening contacting the top electrode. The second insulating cover layer has an oxygen getter property.

A MTJ stack is deposited on a bottom electrode. A metal hard mask is deposited on the MTJ stack and a dielectric mask is deposited on the metal hard mask. A photoresist pattern is formed on the dielectric mask, having a critical dimension of more than about 65 nm. The dielectric and metal hard masks are etched wherein the photoresist pattern is removed. The dielectric and metal hard masks are trimmed to reduce their critical dimension to 10-60 nm and to reduce sidewall surface roughness. The dielectric and metal hard masks and the MTJ stack are etched wherein the dielectric mask is removed and a MTJ device is formed having a small critical dimension of 10-60 nm, and having further reduced sidewall surface roughness.

A method for fabricating a magnetic tunneling junction (MTJ) structure is described. A first dielectric layer is deposited on a bottom electrode and partially etched through to form a first via opening having straight sidewalls, then etched all the way through to the bottom electrode to form a second via opening having tapered sidewalls. A metal layer is deposited in the second via opening and planarized to the level of the first dielectric layer. The remaining first dielectric layer is removed leaving an electrode plug on the bottom electrode. MTJ stacks are deposited on the electrode plug and on the bottom electrode wherein the MTJ stacks are discontinuous. A second dielectric layer is deposited over the MTJ stacks and polished to expose a top surface of the MTJ stack on the electrode plug. A top electrode layer is deposited to complete the MTJ structure.

Methods for forming magnetic tunnel junctions and structures thereof include cryogenic etching the layers defining the magnetic tunnel junction without lateral diffusion of reactive species.

Described is an apparatus which comprises: an input magnet formed of one or more materials with a sufficiently high anisotropy and sufficiently low magnetic saturation to increase injection of spin currents; and a first interface layer coupled to the input magnet, wherein the first interface layer is formed of non-magnetic material such that the first interface layer and the input magnet together have sufficiently matched atomistic crystalline layers.

A method for testing individual memory elements or sets of memory elements of an array of magnetic memory elements. The method involves forming a mask such as photoresist mask over an array memory elements. The mask is configured with an opening over each of the selected memory elements to be tested. The mask can be formed of photoresist which can be patterned by focused electron beam exposure to form opening at features sizes smaller than those available using standard photolithographic processes. An electrically conductive material is deposited over the mask and into the openings in the mask to make electrical contact with the selected memory element or memory elements to be tested. Then, electrical connection can be made with the electrically conductive material to test the selected one or more magnetic memory elements.

An electrical device structure including a magnetic tunnel junction structure having a first tunnel junction dielectric layer positioned between a free magnetization layer and a fixed magnetization layer. A magnetization enhancement stack present on the magnetic tunnel junction structure. The magnetization enhancement stack includes a second tunnel junction layer that is in contact with the free magnetization layer of the magnetic tunnel junction structure, a metal contact layer present on the second tunnel junction layer, and a metal electrode layer present on the metal contact layer. A metallic ring on a sidewall of the magnetic enhancement stack, wherein a base of the metallic ring may be in contact with the free magnetization layer of the magnetic tunnel junction structure.

A stack of connecting metal vias is formed on a bottom electrode by repeating steps of depositing a conductive via layer, patterning and trimming the conductive via layer to form a sub 30 nm conductive via, encapsulating the conductive via with a dielectric layer, and exposing a top surface of the conductive via. A MTJ stack is deposited on the encapsulated via stack. A top electrode layer is deposited on the MTJ stack and patterned and trimmed to form a sub 60 nm hard mask. The MTJ stack is etched using the hard mask to form an MTJ device and over etched into the encapsulation layers but not into the bottom electrode wherein metal re-deposition material is formed on sidewalls of the encapsulation layers underlying the MTJ device and not on sidewalls of a barrier layer of the MTJ device.