Magnetoresistive devices and methods therefor

Patent metadata

Field	Value
Publication number	US-11004899-B2
Application number	US-201916395396-A
Country	US
Kind code	B2
Filing date	Apr 26, 2019
Priority date	Apr 26, 2019
Publication date	May 11, 2021
Grant date	May 11, 2021

Abstract

A magnetoresistive device may include a first ferromagnetic region, a second ferromagnetic region, and an intermediate region positioned between the first ferromagnetic region and the second ferromagnetic region. The intermediate region may be formed of a dielectric material and comprise at least two different metal oxides.

First claim

What is claimed is:

1. A method of manufacturing a magnetoresistive device, comprising:
forming a first ferromagnetic region;
forming an intermediate region on or above the first ferromagnetic region, wherein the intermediate region is formed of a dielectric material comprising at least two different metal oxides; and
forming a second ferromagnetic region on or above the intermediate region;
wherein forming the intermediate region includes (a) depositing a first oxidizable metal on or above the first ferromagnetic region to form a first layer, (b) oxidizing the first layer to form an at least partially oxidized first layer, (c) depositing the first oxidizable metal on or above the at least partially oxidized first layer to form a second layer, (d) oxidizing the second layer to form an at least partially oxidized second layer, (e) depositing the first oxidizable metal on or above the at least partially oxidized second layer to form a third layer, (f) oxidizing the third layer to form an at least partially oxidized third layer, and (g) depositing a second oxidizable metal on at least one of:
(i) the at least partially oxidized first layer prior to step (c);
(ii) the at least partially oxidized second layer prior to step (e); and
(iii) the at least partially oxidized third layer.

2. The method of claim 1 , wherein forming the intermediate region includes (a) depositing a first oxidizable metal and a second oxidizable metal on or above the first ferromagnetic region, and (b) oxidizing the deposited first and second oxidizable metals to form the at least two different metal oxides.

3. The method of claim 1 , wherein forming the intermediate region includes (a) depositing a first oxidizable metal on or above the first ferromagnetic region, (b) oxidizing the deposited first oxidizable metal to form a first metal oxide, (c) depositing a second oxidizable metal on the first metal oxide, and (d) oxidizing the deposited second oxidizable metal to form a second metal oxide.

4. The method of claim 1 , wherein forming the intermediate region includes (a) depositing a first oxidizable metal on or above the first ferromagnetic region, (b) depositing a second oxidizable metal on the first oxidizable metal, and (c) oxidizing the deposited first and second oxidizable metals together to form the at least two different metal oxides.

5. The method of claim 1 , wherein the at least two different metal oxides includes a first metal oxide and a second metal oxide, and wherein (a) the first metal oxide includes an oxide of one of magnesium or aluminum, and (b) the second metal oxide includes an oxide of one of tantalum, aluminum, hafnium, titanium, chromium, zirconium, niobium, molybdenum, tungsten, or ruthenium.

6. The method of claim 1 , wherein forming the intermediate region includes (a) forming a first layer comprising a first oxidizable metal on or above the first ferromagnetic region, (b) oxidizing the first layer to form an at least partially oxidized first layer, (c) forming a second layer comprising the first oxidizable metal on or above the at least partially oxidized first layer, (d) oxidizing the second layer to form an at least partially oxidized second layer, (e) forming a third layer comprising the first oxidizable metal on or above the at least partially oxidized second layer, and (f) oxidizing the third layer to form an at least partially oxidized third layer, wherein at least one of step (a), step (c), or step (e) includes depositing the first oxidizable metal and a second oxidizable metal to form the first, second, or the third layer, and wherein the first and second oxidizable metals are different materials.

7. The method of claim 1 , wherein forming the intermediate region includes (a) depositing a first oxidizable metal on or above the first ferromagnetic region to form a first layer, (b) oxidizing the first layer to form an at least partially oxidized first layer, (c) depositing the first oxidizable metal on or above the at least partially oxidized first layer to form a second layer, (d) oxidizing the second layer to form an at least partially oxidized second layer, (e) depositing the first oxidizable metal on or above the at least partially oxidized second layer to form a third layer, (f) oxidizing the third layer to form an at least partially oxidized third layer, and (g) depositing a second oxidizable metal and oxidizing the deposited second oxidizable metal on at least one of:
(i) the at least partially oxidized first layer prior to step (c);
(ii) the at least partially oxidized second layer prior to step (e); and
(iii) the at least partially oxidized third layer.

8. The method of claim 1 , wherein forming the intermediate region includes (a) depositing a first oxidizable metal on or above the first ferromagnetic region to form a first layer, (b) oxidizing the first layer to form an at least partially oxidized first layer, (c) depositing the first oxidizable metal on or above the at least partially oxidized first layer to form a second layer, (d) oxidizing the second layer to form an at least partially oxidized second layer, (e) depositing the first oxidizable metal on or above the at least partially oxidized second layer to form a third layer, (f) oxidizing the third layer to form an at least partially oxidized third layer, and (g) depositing a second oxidizable metal on at least one of:
(i) the first layer prior to step (b);
(ii) the second layer prior to step (d); and
(iii) the third layer prior to step (f).

9. The method of claim 1 , wherein forming the intermediate region includes:
depositing a first oxidizable metal on or above the first ferromagnetic region;
depositing a second oxidizable metal on or above the first ferromagnetic region; and
oxidizing the first and the second oxidizable metals to form the dielectric material comprising the at least two different metal oxides.

10. A method of manufacturing a magnetoresistive device, comprising:
forming a first ferromagnetic region;
forming an intermediate region on or above the first ferromagnetic region, wherein forming the intermediate region includes:
depositing a first oxidizable metal on or above the first ferromagnetic region;
depositing a second oxidizable metal on or above the first ferromagnetic region, wherein the first and second oxidizable metals are different materials; and
oxidizing the deposited first and the second oxidizable metals in a single oxidation step or multiple oxidation steps to form a dielectric material comprising oxides of the first and second oxidizable metals; and

forming a second ferromagnetic region on or above the intermediate region;
wherein depositing the first oxidizable metal and depositing the second oxidizable metal include co-depositing the first and second oxidizable metals on the first ferromagnetic region.

11. The method of claim 10 , wherein depositing the second oxidizable metal includes depositing the second oxidizable metal on a surface of the deposited first oxidizable metal, and the oxidizing includes oxidizing the deposited first and the second oxidizable metals together in in a single oxidation step.

12. The method of claim 10 , wherein
oxidizing the deposited first and the second oxidizable metals includes (a) oxidizing the deposited first oxidizable metal to form an oxide of the first oxidizable metal in a first oxidation step, and (b) oxidizing the deposited second oxidizable metal to form an oxide of the second oxidizable metal in a second oxidation step, and
depositing the second oxidizable metal includes depositing the second oxidizable metal on the oxide of the first oxidizable metal after the first oxidation step.

1

Assignees

• Everspin Technologies Inc

Inventors

• Aggarwal Sanjeev
• Sun Jijun

Classifications

• H10N50/85

  Materials of the active region · CPC title

• H01L43/08

  Electricity · mapped topic

• H01L43/10

  Electricity · mapped topic

• H01L27/228 Primary

  Electricity · mapped topic

• H01L43/12

  Electricity · mapped topic