Solution deposition of metal salts to form metal oxides

Patent metadata

Field	Value
Publication number	US-2020392012-A1
Application number	US-202016903710-A
Country	US
Kind code	A1
Filing date	Jun 17, 2020
Priority date	Jun 17, 2019
Publication date	Dec 17, 2020
Grant date	—

Abstract

Certain disclosed embodiments concern an organic solution suitable for forming metal oxide films, particularly thins films, comprising a metal salt selected from a Sn salt, an Sb salt, a dopant, and combinations thereof. The salt often is a halide salt, such as SnCl2 or SbCl3. Certain disclosed compositions are preferably formed using substantially pure reagents and may include a dopant, such as a fluoride dopant. Described solutions may be used to form thin films, such as a thin film comprising SnO2, Sb:SnO2, F:SnO2, or (Sb,F):SnO2. Such thin films may have any desired thickness, such as a thickness of from 200 or 700 nm, and are extremely smooth, such as having an RMS surface roughness >3 nm, such as 3 nm to 10 nm, with certain embodiments having an RMS surface roughness <2 nm or <1 nm. Devices can be assembled comprising the thin films on a suitable substrate.

First claim

We claim:

1 . A composition suitable for solution deposition of metal oxide thin films, comprising an organic solvent and a metal salt selected from a Sn salt, an Sb salt, a dopant, and combinations thereof.

2 . The composition according to claim 1 salt is a halide salt.

3 . The composition according to claim 2 wherein the salt is SnCl 2 or SbCl 3 .

4 . The composition according to claim 1 comprising a fluoride dopant selected from HF, NH 4 F, (CH 3 ) 4 NF, CF 3 COOH, SnF 2 , SnF 4 , or a combination thereof.

5 . The solution according to claim 1 where the organic solvent is a nitrile, an ether, or a combination thereof.

6 . The solution according to claim 1 where the solvent is acetonitrile, tetrahydrofuran, or a combination thereof.

7 . The composition according to claim 1 , comprising:
an organic solvent selected from a nitrile, an ether, or a combination thereof; a metal salt selected from SnCl 2 , SbCl 3 , or combinations thereof; and a fluoride dopant selected from HF, NH 4 F, (CH 3 ) 4 NF, CF 3 COOH, SnF 2 , SnF 4 , or a combination thereof.

8 . A solution-deposited thin film comprising SnO 2 , Sb:SnO 2 , F:SnO 2 , or (Sb,F):SnO 2 .

9 . The thin film according to claim 8 having a thickness 200 to 700 nm and an RMS surface roughness >3 nm.

10 . A device, comprising a thin film according to claim 8 .

11 . A method for making a metal oxide thin film, comprising:
preparing an organic solution comprising a metal salt selected from a Sn salt, an Sb salt, a dopant, and combinations thereof, applying the solution to a substrate to form a film; and heating the film.

12 . The method according to claim 11 where the salt is a halide salt.

13 . The method according to claim 12 where the salt is SnCl 2 or SbCl 3 .

14 . The method according to claim 11 comprising a salt having a purity greater than 99.9%.

15 . The method according to any of claim 11 where the dopant is a fluoride dopant selected from HF, NH 4 F, (CH 3 ) 4 NF, CF 3 COOH, SnF 2 , SnF 4 , or a combination thereof.

16 . The method according to claim 11 wherein the solvent is a nitrile, an ether, or a combination thereof.

17 . The method according to claim 16 where the solvent is acetonitrile, tetrahydrofuran, or a combination thereof.

18 . A film made according to claim 11 .

19 . A method for making a device, comprising:
preparing a solution comprising a metal salt, having a purity of at least 99.9%, selected from a Sn salt and an Sb salt, a fluoride dopant selected from HF, NH 4 F, (CH 3 ) 4 NF, CF 3 COOH, SnF 2 , SnF 4 , and combinations thereof, and an organic solvent selected from an ether, a nitrile, or combinations thereof; applying the solution to a substrate to form a film having a thickness 200 or 700 nm and an RMS surface roughness of >3 nm; heating the film; and assembling a device comprising the film.

20 . A device made according to claim 19 .

Assignees

• Univ Oregon State

Inventors

• Perkins Cory K
• Keszler Douglas A

Classifications

• C23C18/1216

  Metal oxides (C23C18/1212 takes precedence) · CPC title

• C01G19/02 Primary

  Oxides · CPC title

• C01G19/00

  Compounds of tin · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01G30/007

  of binary type SbX3 or SbX5 with X representing a halogen, or mixed of the type SbX3X'2 with X,X' representing different halogens · CPC title