Metal oxide thin film, method of producing same, and coating solution for forming metal oxide thin film used in said method

Patent metadata

Field	Value
Publication number	US-2016118253-A1
Application number	US-201614989059-A
Country	US
Kind code	A1
Filing date	Jan 6, 2016
Priority date	Jul 10, 2013
Publication date	Apr 28, 2016
Grant date	—

Abstract

A metal oxide thin film according to the present invention has a peak which is attributed to 1s electrons of nitrogen in a binding energy range of 402 eV to 405 eV in an XPS spectrum obtained by X-ray photoelectron spectroscopy, in which peak areas, which are obtained by separation of peaks having a peak energy of a metal-oxygen bond attributed to 1s electrons of oxygen, satisfy the following expression.
0.9< D/E   (1)

(D represents a peak area of a component having a peak position in a binding energy range of 529 eV or higher and lower than 531 eV, and E represents a peak area of a component having a peak position in a binding energy range of 531 eV to 532 eV)

First claim

What is claimed is:

1 . A metal oxide thin film comprising
a component having a peak position which is attributed to 1s electrons of nitrogen in a binding energy range of 402 eV to 405 eV in an XPS spectrum obtained by X-ray photoelectron spectroscopy, wherein peak areas, which are obtained by separation of peaks attributed to 1s electrons of oxygen, satisfy 0.9<D/E, D represents a peak area of a component having a peak position in a binding energy range of 529 eV or higher and lower than 531 eV, and E represents a peak area of a component having a peak position in a binding energy range of 531 eV to 532 eV.

2 . The metal oxide thin film according to claim 1 ,
wherein in the XPS spectrum, a component having a peak position in a binding energy range of 406 eV to 408 eV is not substantially contained.

3 . The metal oxide thin film according to claim 1 ,
wherein 0.9<D/E≦5.5 is satisfied.

4 . The metal oxide thin film according to claim 3 ,
wherein 1≦D/E≦5.1 is satisfied.

5 . The metal oxide thin film according to claim 3 which is a semiconductor thin film.

6 . The metal oxide thin film according to claim 3 ,
wherein at least indium is contained.

7 . The metal oxide thin film according to claim 6 ,
wherein not only indium but also at least one metal selected from the group consisting of zinc, tin, gallium, and aluminum are contained.

8 . The metal oxide thin film according to claim 6 ,
wherein a content of indium is 50 atom % or higher with respect to all the metal elements contained in the metal oxide thin film.

9 . A thin film transistor comprising the metal oxide thin film according to claim 5 as an active layer.

10 . A display apparatus comprising the thin film transistor according to claim 9 .

11 . A coating solution for forming a metal oxide thin film,
wherein 1<B/(A×C) is satisfied, A represents a mol concentration (mol/L) of metal components contained in the coating solution, B represents a total mol concentration (mol/L) of nitrate ions and nitrite ions in the coating solution, and C represents an average valence when the metal component is a metal oxide thin film.

12 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein 1<B/(A×C)≦1.9 is satisfied.

13 . The coating solution for forming a metal oxide thin film according to claim 12 ,
wherein 1.1≦B(A×C)≦1.6 is satisfied.

14 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein at least indium is contained as the metal.

15 . The coating solution for forming a metal oxide thin film according to claim 14 ,
wherein not only indium but also at least one metal selected from the group consisting of zinc, tin, gallium, and aluminum are contained as the metal.

16 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein the mol concentration A of the metal is 0.01 mol/L to 0.5 mol/L.

17 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein a nitrate of the at least one metal is dissolved in a solvent.

18 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein concentrated nitric acid, fuming nitric acid, or a nitrate is added.

19 . The coating solution for forming a metal oxide thin film according to claim 11 ,
wherein the solvent contains methanol or methoxyethanol.

20 . A method of producing a metal oxide thin film, the method comprising:
a precursor thin film forming step of forming a metal oxide precursor thin film by preparing a substrate, coating the substrate with the coating solution for forming a metal oxide thin film according to claim 11 , and drying the substrate; and a conversion step of converting the metal oxide precursor thin film into an oxide thin film of the metal.

21 . The method of producing a metal oxide thin film according to claim 20 ,
wherein a maximum temperature of the substrate in the conversion step is 200° C. or lower.

22 . The method of producing a metal oxide thin film according to claim 21 ,
wherein a maximum temperature of the substrate in the conversion step is 120° C. or higher.

23 . The method of producing a metal oxide thin film according to claim 20 ,
wherein the conversion step includes a step of irradiating the metal oxide precursor thin film with ultraviolet rays.

24 . The method of producing a metal oxide thin film according to claim 23 ,
wherein, in the ultraviolet irradiation step, the metal oxide precursor thin film is irradiated with ultraviolet rays having a wavelength of 300 nm or shorter at an intensity of 10 mW/cm 2 or higher.

25 . The method of producing a metal oxide thin film according to claim 20 ,
wherein, in the precursor thin film forming step, the drying is performed such that the maximum temperature of the substrate is 35° C. to 100° C.

26 . The method of producing a metal oxide thin film according to claim 20 ,
wherein, in the precursor thin film forming step, the coating is performed using at least one coating method selected from the group consisting of an ink jet method, a dispenser method, a relief printing method, and an intaglio printing method.

27 . A thin film transistor comprising a metal oxide thin film, which is formed using the method of producing a metal oxide thin film according to claim 20 , as an active layer.

28 . A display apparatus comprising the thin film transistor according to claim 27 .

Assignees

• Fujifilm Corp

Inventors

• Takata Masahiro
• Kikuchi Makoto
• Tanaka Atsushi
• Suzuki Masayuki

Classifications

• H10P14/3426

  Oxides · CPC title

• H10P14/265

  using solutions · CPC title

• H10P14/3434 Primary

  being oxide semiconductor materials (Group IIB-VIA semiconductor materials H10P14/3424) · CPC title

• H10D99/00

  Subject matter not provided for in other groups of this subclass · CPC title

• H10D62/80

  characterised by the materials · CPC title