Fabricating correlated electron material (cem) devices

Patent metadata

Field	Value
Publication number	US-2017301859-A1
Application number	US-201715641124-A
Country	US
Kind code	A1
Filing date	Jul 3, 2017
Priority date	Jan 26, 2016
Publication date	Oct 19, 2017
Grant date	—

Abstract

Subject matter disclosed herein may relate to construction of a correlated electron material (CEM) device. In particular embodiments, after formation of a film comprising layers of a transition metal oxide (TMO) material and a dopant, at least a portion of the film may be exposed to an elevated temperature. Exposure of the at least a portion of the film to the elevated temperature may continue until the atomic concentration of the dopant within the film is reduced, which may enable operation of the film as a correlated electron material CEM exhibiting switching of impedance states.

First claim

What is claimed is:

1 . A method of constructing a correlated electron material (CEM) device, comprising:
forming one or more layers of a transition metal oxide (TMO) material on a conductive substrate, the one or more layers of the TMO material comprising a first atomic concentration of an extrinsic ligand; and exposing at least a portion of the one or more layers of the TMO material formed on the conductive substrate, in a chamber, to an elevated temperature until at least a portion of the one or more layers of the TMO material comprises no greater than a second atomic concentration of the extrinsic ligand, the second atomic concentration of the extrinsic ligand to enable a low-impedance or conductive state.

2 . The method of claim 1 , wherein the second atomic concentration of the extrinsic ligand is less than the first atomic concentration of the extrinsic ligand.

3 . The method of claim 1 , wherein the extrinsic ligand acts as a dopant to enable the conductive state of the portion of the one or more layers of the TMO material.

4 . The method of claim 3 , wherein the dopant comprises carbon, carbonyl (CO), nitric oxide (NO), or ammonia (NH 3 ).

5 . The method of claim 1 , further comprising forming a conductive overlay on the one or more layers of TMO material prior to exposing the one or more layers of the TMO material formed on the conductive substrate to the elevated temperature.

6 . The method of claim 5 , wherein exposing to the elevated temperature is performed at least until a conductive oxide layer is formed at an interface between the conductive substrate and the TMO material.

7 . The method of claim 6 , wherein the conductive substrate comprises at least 50.0% atomic concentration of iridium, and wherein the conductive oxide layer comprises iridium oxide.

8 . The method of claim 6 , wherein the conductive substrate comprises at least 50.0% atomic concentration of ruthenium, and wherein the conductive oxide layer comprises ruthenium oxide.

9 . The method of claim 6 , wherein the conductive oxide layer comprises a sub-monolayer, of the conductive oxide, a monolayer of the conductive oxide, or a plurality of layers of the conductive oxide.

10 . The method of claim 1 , wherein exposing the one or more layers of the TMO material formed on the conductive substrate to the elevated temperature brings about an atomic concentration of the extrinsic ligand of about 0.1% to about 15.0%.

11 . The method of claim 10 , wherein the portion of the one or more layers of the TMO material to be placed in the low-impedance or conductive state is capable of transitioning from the low-impedance or conductive state to a high-impedance or insulative state.

12 . The method of claim 1 , wherein the elevated temperature comprises a range of between about 200.0° C. to about 500.0° C., and wherein the one or more layers of the TMO material are exposed to the elevated temperature for a duration of about 1.0 minute to about 60.0 minutes.

13 . The method of claim 1 , wherein the elevated temperature is achieved via one or more laser pulses having a duration of between 0.5 μs and 2.0 μs to provide a temperature equal to about 900.0° C. to about 1500.0° C. at the portion of the one or more layers of the TMO material.

14 . The method of claim 1 , wherein the elevated temperature is achieved utilizing one or more pulses of a flashlamp for duration of between about 250.0 μs and about 2.0 seconds to provide a temperature equal to about 900.0° C. to about 1500.0° C. at the portion of the one or more layers of the TMO material.

15 . The method of claim 1 , wherein the first atomic concentration of the extrinsic ligand comprises between about 0.1% and about 50.0%.

16 . A method of fabricating a correlated electron material (CEM) device, comprising:
depositing a film of a transition metal oxide (TMO) material on a conductive substrate, the TMO material comprising an atomic concentration of an extrinsic ligand; and exposing at least a portion of the film of the TMO material, in a chamber, to an elevated temperature to reduce the atomic concentration of the extrinsic ligand until at least a portion of the film of the TMO material is capable of switching between a conductive state and a substantially dissimilar insulative state.

17 . The method of claim 16 , wherein the portion of the film of the TMO material, operating in the substantially dissimilar insulative state exhibits a resistance at least 5.0 times greater than the resistance exhibited in the conductive state.

18 . The method of claim 16 , wherein the extrinsic ligand corresponds to carbon, carbonyl (CO), nitric oxide (NO), or ammonia (NH 3 ).

19 . The method of claim 16 , further comprising forming a conductive overlay on the film of TMO material prior to exposing the film of TMO material to the elevated temperature.

20 . The method of claim 16 , wherein the conductive substrate comprises at least 50.0% atomic concentration of iridium or at least 50.0% atomic concentration of ruthenium, and wherein exposing acts to form at least a submonolayer of iridium oxide or ruthenium oxide at an interface between the film of the TMO material and the conductive substrate.

21 . The method of claim 16 , wherein the portion of the TMO material comprises a born-on or conductive attribute.

22 . The method of claim 16 , wherein the elevated temperature comprises a range of between about 200.0° C. to about 500.0° C., and wherein the film of the TMO material are exposed for a duration of about 1.0 minute to about 60.0 minutes.

23 . The method of claim 16 , wherein the elevated temperature is achieved via one or more laser pulses having a duration of between 0.5 μs and 2.0 μs to provide a temperature equal to about between 900.0° C. to about 1500.0° C. at the portion of the film of the TMO material.

24 . The method of claim 16 , wherein the elevated temperature is achieved utilizing one or more pulses of a flashlamp for duration of about 250.0 μs and about 2.0 seconds to provide a temperature equal to between about 900.0° C. to about 1500.0° C. at the portion of the film of the TMO material.

25 . The method of claim 16 , wherein the atomic concentration of the extrinsic ligand comprises between about 0.1% and about 50.0%.

26 . A method of fabricating a correlated electron material (CEM) device, comprising:
depositing a film of a transition metal oxide (TMO) material on a conductive substrate, the TMO material comprising a first atomic concentration of an extrinsic ligand; and evaporating a portion of the extrinsic ligand from the film of the TMO material, in a chamber, until at least a portion of the film of the TMO material is capable of switching between a relatively conductive state and a substantially dissimilar insulative state.

27 . The method of claim 26 , wherein evaporating the portion of the extrinsic ligand from the film of the TMO material comprises exposing the film of the TMO material to a temperature of between about 150.0° C. to about 600.0° C. for a duration of between about 1.0 minute and about 60.0 minutes.

28 . The method of claim 26 , wherein evaporating the portion of the extrinsic ligand from the film of the TMO material comprises exposing the film of the TMO material to one or more laser pulses having a duration of between 0.5 μs and 2.0 μs to provide a temperature between about

Assignees

• Advanced Risc Mach Ltd

Inventors

• Paz De Araujo Carlos Alberto
• Celinska Jolanta Bozena
• Shifren Lucian

Classifications

• C23C16/406

  of iron group metals · CPC title

• C23C16/45525

  Atomic layer deposition [ALD] · CPC title

• H01L45/146 Primary

  Electricity · mapped topic

• H01L45/1253

  Electricity · mapped topic

• H01L45/1616

  Electricity · mapped topic