Magnetic tunnel junctions

• US 10,062,835 B2
• Filed: 05/08/2017
• Issued: 08/28/2018
• Est. Priority Date: 05/13/2016
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Chen, Wei, Kula, Witold, Siddik, Manzar, Ramarajan, Suresh, Harms, Jonathan D.
• Primary Examiner(s): Abdelaziez, Yasser A
• Application Number:
  US15/588,994
• Publication Number:
  US 20170331032A1
• Time in Patent Office: 477 Days
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: H10B 61/10 comprising components having two electrodes, e.g. diodes or MIM elements
• CPC Class Codes: H10N 50/10 Magnetoresistive devices
• CPC Class Codes: H10N 50/80 Constructional details
• CPC Class Codes: H10N 50/85 Magnetic active materials

Abstract

A magnetic tunnel junction comprises a conductive first magnetic electrode comprising magnetic recording material, a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material, and a non-magnetic tunnel insulator material between the first and second electrodes. The magnetic reference material of the second electrode comprises a synthetic antiferromagnetic construction comprising two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other. The one magnetic region comprises a polarizer region comprising Co_xFe_yB_z where “x” is from 0 to 90, “y” is from 10 to 90, and “z” is from 10 to 50. The Co_xFe_yB_z is directly against the tunnel insulator. A non-magnetic region comprising an Os-containing material is between the two spaced magnetic regions. The other magnetic region comprises a magnetic Co-containing material. Other embodiments are disclosed.

Claims

1. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the first magnetic electrode comprising dielectric material, the magnetic recording material being between the dielectric material and the tunnel insulator, the first magnetic electrode comprising non-magnetic conductive material, the dielectric material being between the non-magnetic conductive material and the magnetic recording material, the first magnetic electrode being devoid of any magnetic polarizer region between the dielectric material and the non-magnetic conductive material; and

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions, the Os-containing material being directly against the Co_xFe_yB_z; and

the other spaced magnetic region comprising magnetic Co-containing material directly against the Os-containing material; and

non-magnetic Ni_sFe_tCr_u directly against the magnetic Co-containing material, where “

s”

is from 50 to 100, “

t”

is from 0 to 30, and “

u”

is from 0 to 45;

the Co-containing material being between the Os-containing material and the non-magnetic Ni_sFe_tCr_u.

2. The magnetic tunnel junction of claim 1 wherein the Co-containing material is elemental Co.

3. The magnetic tunnel junction of claim 1 wherein the magnetic recording material comprises 3 Angstroms thick Fe directly against an alloy comprising Co, Fe, and B that is 10 Angstroms thick.

4. The magnetic tunnel junction of claim 1 wherein the one magnetic region comprises at least one of elemental W, elemental Mo, elemental Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50.

5. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions;

the other magnetic region comprising a magnetic Co-containing material; and

the one magnetic region comprises at least one of elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50; and

the magnetic recording material comprising at least two of the elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z.

6. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions;

the other magnetic region comprising a magnetic Co-containing material; and

the one magnetic region comprises at least one of elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50; and

the magnetic recording material comprising elemental-form W, elemental-form Mo directly against the Co_xFe_yB_z.

7. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions;

the other magnetic region comprising a magnetic Co-containing material; and

the one magnetic region comprises at least one of elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50; and

the magnetic recording material comprising elemental-form Mo directly against the Co_xFe_yB_z.

8. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions;

the other magnetic region comprising a magnetic Co-containing material; and

the one magnetic region comprises at least one of elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50; and

the magnetic recording material comprising elemental-form Fe directly against the Co_xFe_yB_z.

9. A magnetic tunnel junction comprising:

a conductive first magnetic electrode comprising magnetic recording material;

a conductive second magnetic electrode spaced from the first electrode and comprising magnetic reference material;

a non-magnetic tunnel insulator material between the first and second electrodes;

the magnetic reference material of the second electrode comprising a synthetic antiferromagnetic construction comprising;

two spaced magnetic regions one of which is closer to the tunnel insulator material than is the other, the one magnetic region comprising a polarizer region comprising Co_xFe_yB_z where “

x”

is from 0 to 90, “

y”

is from 10 to 90, and “

z”

is from 10 to 50;

the Co_xFe_yB_z being directly against the tunnel insulator;

a non-magnetic region comprising an Os-containing material between the two spaced magnetic regions;

the other magnetic region comprising a magnetic Co-containing material; and

the one magnetic region comprises at least one of elemental-form W, elemental-form Mo, elemental-form Fe, Co_aFe_bW_c, Co_aFe_bMo_c, and Co_aFe_bTa_c directly against the Co_xFe_yB_z, where “

a”

is from 0 to 50, “

b”

is from 50 to 99, and “

c”

is from 1 to 50; and

the magnetic recording material comprising Co_aFe_bTa_c directly against the Co_xFe_yB_z.