A magnetic tunneling junction (MTJ) device and fabrication method is disclosed. In a particular embodiment, an apparatus is disclosed that includes an MTJ device. The MTJ device includes a free layer and a spin torque enhancing layer. The spin torque enhancing layer includes a nano-oxide layer.

Magnetic tunnel junction device and fabrication

A method for fabricating a semiconductor device, in which a lifting phenomenon can be prevented from occurring in forming an amorphous carbon film on an etched layer having tensile stress. According to the invention, since a compression stress on the etched layer or the amorphous carbon film can be reduced or a compression stress film is formed between the etched layer or the amorphous carbon film to prevent a lifting phenomenon from occurring and thus another pattern can be formed to fabricate a highly integrated semiconductor device.

Method for Fabricating Semiconductor Device

A method of manufacturing a magnetoresistive-based device having magnetic material layers formed between a first electrically conductive layer and a second electrically conductive layer, the magnetic materials layers including a tunnel barrier layer formed between a first magnetic materials layer and a second magnetic materials layer, including removing the first electrically conductive layer and the first magnetic materials layer unprotected by a first hard mask, to form a first electrode and a first magnetic materials, respectively; and removing the tunnel barrier layer, second magnetic materials layer, and second electrically conductive layer unprotected by the second hard mask to form a tunnel barrier, second magnetic materials, and a second electrode.

Method of manufacturing a magnetoresistive-based device

A tunneling magnetoresistive read head produced thereby are disclosed. A shield layer is provided. A magnetic etch-stop layer is formed over the shield layer, where the magnetic etch-stop layer comprises a nonmagnetic metal and a soft magnetic material with overall property still being magnetically soft. A sensor stack is formed over the magnetic etch-stop layer. A patterned mask layer is formed over the sensor stack. Material from a portion of the sensor stack not covered by the patterned mask is removed.

Magnetic etch-stop layer for magnetoresistive read heads

A process is provided for etching a mask layer and removal of residue from a structure having an area sheltered from directional etching. The structure has a shape that forms a silhouette area obstructed from being etched by anisotropic bombardment originating from a first direction, and a mask formed over the mask layer over the structure; A first etch process removes at least a part of the mask layer and retains at least a part of mask layer in the sheltered area. A second etch process removes at least a part of the mask layer in the sheltered area by hydrogen based microwave plasma etching.

Process for masking and removal of residue from complex shapes

A process is described for making contact to the buried capping layers of GMR and MTJ devices without the need to form and fill via holes. CMP is applied to the structure in three steps: (1) conventional CMP (2) a Highly Selective Slurry (HSS) is substituted for the conventional slurry to just expose the capping layer, and (3) the HSS is diluted and used to clean the surface as well as to cause a slight protrusion of the capping layers above the surrounding dielectric surface, making it easier the contact them without damaging the devices below.

Use of CMP to contact a MTJ structure without forming a via

An MTJ cell without footings and free from electrical short-circuits across a tunneling barrier layer is formed by using a Ta hard mask layer and a combination of etches. A first etch patterns the Ta hard mask, while a second etch uses O 2 applied in a single high power process at two successive different power levels. A first power level of between approximately 200 W and 500 W removes BARC, photoresist and Ta residue from the first etch, the second power level, between approximately 400 W and 600 W continues an etch of the stack layers and forms a protective oxide around the etched sides of the stack. Finally, an etch using a carbon, hydrogen and oxygen gas completes the etch while the oxide layer protects the cell from short-circuits across the lateral edges of the barrier layer.

Method of MRAM fabrication with zero electrical shorting

Formation of a bottom electrode for an MTJ device on a silicon nitride substrate is facilitated by including a layer of ruthenium near the silicon nitride surface. The ruthenium is a good electrical conductor and it responds differently from Ta and TaN to certain etchants. Adhesion to SiN is enhanced by using a TaN/NiCr bilayer as “glue”. Thus, said included layer of ruthenium may be used as an etch stop layer during the etching of Ta and/or TaN while the latter materials may be used to form a hard mask for etching the ruthenium without significant corrosion of the silicon nitride surface.

Bottom electrode for MRAM device and method to fabricate it

Formation of a bottom electrode for an MTJ device on a silicon nitride substrate is facilitated by including a protective coating that is partly consumed during etching of the alpha tantalum portion of said bottom electrode. Adhesion to SiN is enhanced by using a TaN/NiCr bilayer as “glue”.

Process to fabricate bottom electrode for MRAM device

A multi-layered bottom electrode for an MTJ device on a silicon nitride substrate is described. It comprises a bilayer of alpha tantalum on ruthenium which in turn lies on a nickel chrome layer over a second tantalum layer.

Tom Zhong

Papers

Use of CMP to contact a MTJ structure without forming a via

Method of MRAM fabrication with zero electrical shorting

Bottom electrode for MRAM device and method to fabricate it

Process to fabricate bottom electrode for MRAM device

Bottom electrode for MRAM device