Process for the preparation of aluminum scandium nitride films

Patent metadata

Field	Value
Publication number	US-2024229221-A1
Application number	US-202218559576-A
Country	US
Kind code	A1
Filing date	May 12, 2022
Priority date	May 12, 2021
Publication date	Jul 11, 2024
Grant date	—

Abstract

This invention provides a process for the preparation of aluminum scandium nitride films. This invention further provides Caluminum scandium nitride films and layers, and devices and systems comprising aluminum scandium nitride films.

First claim

1 . A process for the preparation of Al x Sc 1-x N film, said process comprising:
a) providing a substrate; b) producing a Ti first layer on said substrate; c) depositing AlSc on said first layer; wherein said deposition is carried out in the presence of nitrogen gas, thus producing (AlSc)N layer, wherein a TiN layer in formed between said Ti first layer and between said (AlSc)N layer.

2 . The process of claim 1 , wherein steps (b)-(c) are performed by sputtering in a sputtering chamber.

3 . (canceled)

4 . (canceled)

5 . (canceled)

6 . (canceled)

7 . The process of claim 1 , wherein step (c) is carried out at a temperature ranging between 25° C. and 600° C.

8 . (canceled)

9 . The process of claim 1 , wherein 0.57≤x≤1.

10 . The process of claim 9 , wherein said Al x Sc 1-x N is Al 0.50 Sc 0.2 N or Al 0.75 Sc 0.25 N or Al 0.7 Sc 0.3 N.

11 . The process of claim 1 , wherein the thickness of said Al x Sc 1-x N layer is greater than 0.8 μm.

12 . The process of claim 1 , wherein prior to step (b), said substrate is cleaned.

13 . The process of claim 12 , wherein said cleaning comprises the use of:
organic or inorganic solvent; and/or organic or inorganic acid; and/or gas plasma.

14 . The process of claim 1 , wherein:
step (b) is conducted at room temperature; and step (c) is conducted at a temperature ranging between 25° C. to 400° C.

15 . The process of claim 1 , wherein:
step (b) is conducted under argon; and step (c) is conducted under a gas further comprising argon.

16 . The process of claim 15 , wherein step (b) or step (c)-step-(d) or any combination thereof is conducted at a pressure lower than 1 atm.

17 . The process of claim 1 , further comprising producing a top layer comprising an electrically conductive material on said Al x Sc 1-x N layer.

18 . The process of claim 17 , wherein the electrically conductive material is selected from Cu, Ag, Au, Pt, Pd, Ni, Al, Ta and Ti or a combination thereof.

19 . The process of claim 18 , wherein the top layer comprises Ti.

20 . The process of claim 17 , wherein said Ti first layer and said top layer are used as electrodes.

21 . The process of claim 20 , wherein said electrodes are independently connected to a power supply.

22 . The process of claim 1 , wherein the thickness of the combined Ti layer and TiN layer is between 50-300 nm.

23 . A Ti/TiN layer made by the process of claim 1 , wherein the thickness of the layer is between 50-300 nm.

24 . An Al x Sc 1-x N layer made by the process of claim 1 .

25 . (canceled)

26 . A polycrystalline Al x Sc 1-x N film wherein:
a. the orientation of said film is 001/002; or b. the piezoelectric coefficient of said film ranges between 1.0 C/m 2 and 4.0 C/m 2 ; or c. the compressive stress of said film ranges between 5 MPa and 500 MPa; or d. any combination thereof.

27 . (canceled)

28 . (canceled)

29 . A piezoelectric device comprising:
a. a substrate; b. a first Ti layer comprising Ti on said substrate; c. TiN layer in contact with said Ti layer; d. a layer comprising Al x Sc 1-x N in contact with said TiN; and e. a top layer comprising an electrically conductive material on said Al x Sc 1-x N layer.

30 . (canceled)

31 . (canceled)

32 . A cantilever comprising the Al x Sc 1-x N layer of claim 1 .

33 . A micro electro-mechanical system (MEMS) comprising the Al x Sc 1-x N layer of claim 1 .

Assignees

• Yeda Res & Dev

Inventors

• Lubomirsky Igor
• Ehre David
• Cohen Asaf

Classifications

• C23C14/025

  Metallic sublayers · CPC title

• C23C14/021

  Cleaning or etching treatments · CPC title

• C23C14/0036 Primary

  Reactive sputtering · CPC title

• H10N30/079

  using intermediate layers, e.g. for growth control · CPC title

• H10N30/076

  by vapour phase deposition · CPC title