Patent classifications
H01F10/3295
SPIN-TRANSFER TORQUE MAGNETORESISTIVE MEMORY DEVICE WITH A FREE LAYER STACK INCLUDING MULTIPLE SPACERS AND METHODS OF MAKING THE SAME
A spin-transfer torque (STT) magnetoresistive memory device includes a first electrode, a second electrode, and a magnetic tunnel junction located between the first electrode and the second electrode. The magnetic tunnel junction includes a reference layer having a fixed magnetization direction, a free layer stack, and a nonmagnetic tunnel barrier layer located between the reference layer and the free layer stack. The free layer stack has a total thickness of less than 2 nm, and contains in order, a proximal ferromagnetic layer located proximal to the nonmagnetic tunnel barrier layer, a first non-magnetic metal sub-monolayer, an intermediate ferromagnetic layer, a second non-magnetic metal sub-monolayer, and a distal ferromagnetic layer.
Magnetic tunnel junction with low defect rate after high temperature anneal for magnetic device applications
A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400° C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.
Magnetic memory element incorporating dual perpendicular enhancement layers
The present invention is directed to a magnetic memory element including a magnetic free layer structure incorporating two magnetic free layers separated by a perpendicular enhancement layer (PEL) and having a variable magnetization direction substantially perpendicular to layer planes thereof; an insulating tunnel junction layer formed adjacent to the magnetic free layer structure; a magnetic reference layer structure formed adjacent to the insulating tunnel junction layer opposite the magnetic free layer structure; an anti-ferromagnetic coupling layer formed adjacent to the magnetic reference layer structure; and a magnetic fixed layer formed adjacent to the anti-ferromagnetic coupling layer. The magnetic reference layer structure includes first, second, and third magnetic reference layers separated by two PELs and having a first invariable magnetization direction substantially perpendicular to layer planes thereof. The magnetic fixed layer has a second invariable magnetization direction substantially opposite to the first invariable magnetization direction.
Multilayer spacer between magnetic layers for magnetic device
The disclosed technology relates generally to the field of magnetic devices, in particular to magnetic memory devices or logic devices. The disclosed technology presents a magnetic structure for a magnetic device, wherein the magnetic structure comprises a magnetic reference layer (RL); a spacer provided on the magnetic RL, the spacer comprising a first texture breaking layer provided on the magnetic RL, a magnetic bridge layer provided on the first texture breaking layer, and a second texture breaking layer provided on the magnetic bridge layer. Further, the magnetic structure comprising a magnetic pinned layer (PL) or hard layer (HL) provided on the spacer, wherein the magnetic RL and the magnetic PL or HL are magnetically coupled across the spacer through direct exchange interaction.
Magnetic Tunnel Junction with Low Defect Rate after High Temperature Anneal for Magnetic Device Applications
A magnetic tunnel junction is disclosed wherein the reference layer and free layer each comprise one layer having a boron content from 25 to 50 atomic %, and an adjoining second layer with a boron content from 1 to 20 atomic %. One of the first and second layers in each of the free layer and reference layer contacts the tunnel barrier. Each boron containing layer has a thickness of 1 to 10 Angstroms and may include one or more B layers and one or more Co, Fe, CoFe, or CoFeB layers. As a result, migration of non-magnetic metals along crystalline boundaries to the tunnel barrier is prevented, and the MTJ has a low defect count of around 10 ppm while maintaining an acceptable TMR ratio following annealing to temperatures of about 400° C. The boron containing layers are selected from CoB, FeB, CoFeB and alloys thereof including CoFeNiB.
Magnetic memory element incorporating dual perpendicular enhancement layers
The present invention is directed to a magnetic memory element including a magnetic free layer structure incorporating three magnetic free layers separated by two perpendicular enhancement layers (PELs) and having a variable magnetization direction substantially perpendicular to layer planes thereof; an insulating tunnel junction layer formed adjacent to the magnetic free layer structure; a first magnetic reference layer formed adjacent to the insulating tunnel junction layer opposite the magnetic free layer structure; a second magnetic reference layer separated from the first magnetic reference layer by a third perpendicular enhancement layer; an anti-ferromagnetic coupling layer formed adjacent to the second magnetic reference layer; and a magnetic fixed layer formed adjacent to the anti-ferromagnetic coupling layer. The first and second magnetic reference layers have a first invariable magnetization direction substantially perpendicular to layer planes thereof. The magnetic fixed layer has a second invariable magnetization direction substantially opposite to the first invariable magnetization direction.
Methods and apparatus of high moment free layers for magnetic tunnel junctions
The present disclosure generally relates to magnetoresistive device apparatus and methods. The magnetoresistive device includes a read head. The read head is a tunneling magnetoresistive reader that includes a multilayer free layer structure. The multilayer structure includes one or more layers of Co or FCC FeCo sandwiched between a BCC CoFe50 nanolayer and an amorphous CoFeB layer. The one or more layers of Co or FCC FeCo create nanocrystalline disorder that allows the thickness of the amorphous CoFeB layer to be reduced while retaining or even improving TMR and reducing the interlayer coupling field.
Magnetic memory device and manufacturing method of the same
According to one embodiment, a magnetic memory device includes a stacked structure including a first magnetic layer having a fixed magnetization direction, a nonmagnetic layer provided on the first magnetic layer, and a second magnetic layer provided on the nonmagnetic layer and having a variable magnetization direction, a first insulating layer provided along a side surface of the stacked structure and having an upper end located at a position lower than an upper end of the side surface of the stacked structure, and a second insulating layer covering the first insulating layer and having an upper end located at a position higher than the upper end of the first insulating layer.
MULTILAYER SPACER BETWEEN MAGNETIC LAYERS FOR MAGNETIC DEVICE
The disclosed technology relates generally to the field of magnetic devices, in particular to magnetic memory devices or logic devices. The disclosed technology presents a magnetic structure for a magnetic device, wherein the magnetic structure comprises a magnetic reference layer (RL); a spacer provided on the magnetic RL, the spacer comprising a first texture breaking layer provided on the magnetic RL, a magnetic bridge layer provided on the first texture breaking layer, and a second texture breaking layer provided on the magnetic bridge layer. Further, the magnetic structure comprising a magnetic pinned layer (PL) or hard layer (HL) provided on the spacer, wherein the magnetic RL and the magnetic PL or HL are magnetically coupled across the spacer through direct exchange interaction.
MAGNETORESISTIVE ELEMENT, MAGNETIC MEMORY DEVICE, AND WRITING AND READING METHOD FOR MAGNETIC MEMORY DEVICE
Provided are a magnetoresistive element, a magnetic memory device, and a writing and reading method for a magnetic memory device, in which an aspect ratio of a junction portion can be decreased. A magnetoresistive element 1 of the invention, includes: a heavy metal layer 2 that is an epitaxial layer; and a junction portion 3 including a recording layer 31 that is provided on the heavy metal layer 2 and includes a ferromagnetic layer of an epitaxial layer magnetized in an in-plane direction, which is an epitaxial layer, a barrier layer 32 that is provided on the recording layer 31 and includes an insulating body, and a reference layer 33 that is provided on the barrier layer 32 and has magnetization fixed in the in-plane direction, in which the recording layer 31 is subjected to magnetization reversal by applying a write current to the heavy metal layer 2.