Electrical write/read of high-information-density magnetic thin film

Patent metadata

Field	Value
Publication number	US-2023395112-A1
Application number	US-202318327725-A
Country	US
Kind code	A1
Filing date	Jun 1, 2023
Priority date	Jun 2, 2022
Publication date	Dec 7, 2023
Grant date	—

Abstract

According to certain aspects of the present disclosure, a device is provided. The device includes a thin film of cobalt. A platinum layer is disposed on the thin film of cobalt. An aluminum layer is disposed on the platinum layer. The aluminum layer disposed on the platinum layer encapsulates the thin film of cobalt. A plurality of electrical contacts is in electrical communication with the thin film of cobalt. Two electrical contacts of the plurality of electrical contacts are configured to receive a write-current therebetween. Four electrical contacts of the plurality of contacts are configured for reading a 4-point resistance.

First claim

1 . A device, comprising:
a thin film of cobalt; a platinum layer disposed on the thin film of cobalt; an aluminum layer disposed on the platinum layer, wherein the aluminum layer disposed on the platinum layer encapsulates the thin film of cobalt; and a plurality of electrical contacts in electrical communication with the thin film of cobalt, wherein two electrical contacts of the plurality of electrical contacts are configured to receive a write-current therebetween, and wherein four electrical contacts of the plurality of electrical contacts are configured for reading a 4-point resistance.

2 . The device of claim 1 , wherein the thin film of cobalt is 0.8 nm, the aluminum layer is 2 nm, and the platinum layer is 2 nm.

3 . The device of claim 2 , wherein the thin film of cobalt is square shaped with a lateral dimension of 25 microns.

4 . The device of claim 1 , wherein the plurality of electrical contacts includes eight (8) electrical contacts.

5 . The device of claim 4 , wherein the plurality of electrical contacts is gold.

6 . The device of claim 1 , wherein the write-current is 10 milliamp.

7 . The device of claim 6 , wherein two electrical contracts of the four electrical contracts of the plurality of electrical contacts are configured to receive a read-current therebetween and another two electrical contracts of the four electrical contacts of the plurality of electrical contacts are configured for reading a resistivity thereacross.

8 . The device of claim 7 , wherein the read-current is 0.1 milliamp.

9 . A method of fabricating a ferromagnetic thin film device, the method comprising:
transferring a thin film of cobalt out of a vacuum environment; depositing a platinum layer to the thin film of cobalt; depositing an aluminum layer to encapsulate the platinum layer deposited on the thin film of cobalt and the thin film of cobalt; patterning the thin film of cobalt, the platinum layer, and the aluminum layer; and depositing a plurality of electrical contacts to the aluminum layer.

10 . The method of claim 9 , wherein depositing the platinum layer to the thin film of cobalt and depositing the aluminum layer to encapsulate the platinum layer deposited on the thin film of cobalt are performed via sputter deposition.

11 . The method of claim 9 , wherein patterning the thin film of cobalt, the platinum layer, and the aluminum layer is performed by one of photolithography and electron beam lithography.

12 . The method of claim 9 , wherein depositing the plurality of electrical contacts to the aluminum layer is performed via metal deposition and liftoff.

13 . The method of claim 12 , wherein the plurality of electrical contacts are gold.

14 . A device comprising:
a memristive film; and a plurality of electrical contacts in electrical communication with the memristive film, wherein two electrical contacts of the plurality of electrical contacts are configured to receive a write-current therebetween, and wherein four electrical contacts of the plurality of electrical contacts are configured for reading a 4-point resistance.

15 . The device of claim 14 , wherein two electrical contracts of the four electrical contracts of the plurality of electrical contacts are configured to receive a read-current therebetween and another two electrical contracts of the four electrical contacts of the plurality of electrical contacts are configured for reading a resistivity thereacross.

16 . The device of claim 15 , wherein the memristive film comprises a film of cobalt being square shaped with a lateral dimension of 25 microns.

17 . The device of claim 15 , wherein the read-current is 0.1 milliamp.

18 . The device of claim 14 , wherein the plurality of electrical contacts includes eight (8) electrical contacts.

19 . The device of claim 18 , wherein the plurality of electrical contacts is gold.

20 . The device of claim 14 , wherein the write-current is 10 milliamp.

Assignees

• Univ Northwestern

Inventors

• Grayson Matthew A
• Khalili-Amiri Pedram
• Wang Chulin
• Onsager Claire Cecelia
• Arpaci Sevde Nur
• Dominguez Victor Lopez

Classifications

• G11C11/15 Primary

  using multiple magnetic layers (G11C11/155 takes precedence) · CPC title

• G11B5/3116

  Shaping of layers, poles or gaps for improving the form of the electrical signal transduced, e.g. for shielding, contour effect, equalizing, side flux fringing, cross talk reduction between heads or between heads and information tracks (G11B5/3113, G11B5/245 take precedence) · CPC title

• G11B5/3169 Primary

  Working or finishing the interfacing surface of heads, e.g. lapping of heads · CPC title

• G11C11/161

  details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell · CPC title

• G11C27/00

  Electric analogue stores, e.g. for storing instantaneous values · CPC title