Organic reactants for atomic layer deposition

• US 10,612,137 B2
• Filed: 07/08/2016
• Issued: 04/07/2020
• Est. Priority Date: 07/08/2016
• Status: Active Grant

• Current Assignee: ASM IP Holding B.V. (ASM International NV)
• Original Assignee: ASM IP Holdings B.V.
• Inventors: Niskanen, Antti, Tois, Eva, Suemori, Hidemi, Haukka, Suvi
• Primary Examiner(s): Turocy, David P
• Application Number:
  US15/205,827
• Publication Number:
  US 20180010247A1
• Time in Patent Office: 1,369 Days
• CPC Class Codes: C23C 16/04 Coating on selected surface areas, e.g. using masks
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/40 Oxides
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45553 characterized by the use of precursors specially adapted for ALD

Abstract

A method for selectively depositing a metal oxide film is disclosed. In particular, the method comprises pulsing a metal or semi-metal precursor onto the substrate and pulsing an organic reactant onto the substrate. A reaction between the metal or semi-metal precursor and the organic reactant selectively forms a metal oxide film on either a dielectric layer or a metal layer.

Claims

1. A method of selectively forming a metal oxide comprising:

providing a substrate comprising a dielectric layer and a layer comprising metal for processing in a reaction chamber;

exposing the substrate to a metal or semi-metal precursor;

exposing the substrate to one or more of a first purging step and a vacuum;

exposing the substrate to an organic reactant comprising at least one of a carboxylic acid and an aldehyde; and

exposing the substrate to one or more of a second purging step and the vacuum;

wherein a reaction between the metal or semi-metal precursor and the organic reactant selectively forms a metal oxide layer comprising germanium oxide on the dielectric layer,

wherein a selectivity of formation of the metal oxide layer on the dielectric layer, as defined as a ratio of a first amount formed on the dielectric layer minus a second amount formed on the layer comprising metal to the first amount, is greater than 50%, and

wherein the metal or semi-metal precursor comprises one or more of an alkoxide ligand, an amine ligand, and an alkylamine ligand;

wherein exposing the substrate to the organic reactant comprises removing passivation from the layer comprising metal.

2. The method of claim 1, wherein exposing the substrate to the organic reactant comprises reducing metallic materials in the layer comprising metal to elemental metal.

3. The method of claim 2, wherein reducing the metallic materials in the layer comprising metal to elemental metal facilitates the selectivity.

4. The method of claim 1, wherein removing the passivation facilitates the selectivity.

5. The method of claim 1, wherein the metal or semi-metal precursor comprises at least germanium.

6. The method of claim 1, wherein the organic reactant has less than about 5% of water.

7. The method of claim 1, wherein the organic reactant has less than about 1% of water.

8. The method of claim 1, wherein the organic reactant has purity of more than about 98%.

9. The method of claim 1, wherein exposing the substrate to the metal or semi-metal precursor and exposing the substrate to the organic reactant are performed with both the dielectric layer and the layer comprising metal exposed.

10. The method of claim 1, wherein the organic reactant comprises an aldehyde.

11. The method of claim 10, wherein the aldehyde comprises at least one of formaldehyde, acetaldehyde, and butyraldehyde.

12. The method of claim 1, wherein the dielectric layer comprises metal oxide.

13. The method of claim 1, wherein exposing the substrate to the organic reactant comprises decomposing the organic reactant to carbon monoxide and hydrogen gas, wherein the method does not include directly supplying hydrogen gas to reaction chamber.

14. The method of claim 1, wherein the layer comprising metal comprises metal, metallic or conductive material and is not oxidized during the selective formation of the metal oxide.

15. The method of claim 1, wherein the selectivity is more than about 90%.

16. A method of selectively forming a metal oxide comprising:

providing a substrate comprising a dielectric layer and a layer comprising metal for processing in a reaction chamber;

exposing the substrate to a metal or semi-metal precursor;

exposing the substrate to one or more of a first purging step and a vacuum;

exposing the substrate to an organic reactant comprising at least one of a carboxylic acid and an aldehyde; and

exposing the substrate to one or more of a second purging step and the vacuum;

wherein a reaction between the metal or semi-metal precursor and the organic reactant selectively forms a metal oxide layer comprising germanium oxide on the dielectric layer,

wherein a selectivity of formation of the metal oxide layer on the dielectric layer, as defined as a ratio of a first amount formed on the dielectric layer minus a second amount formed on the layer comprising metal to the first amount, is greater than 50%, and

wherein the metal or semi-metal precursor comprises one or more of an alkoxide ligand, an amine ligand, and an alkylamine ligand;

wherein exposing the substrate to the organic reactant comprises reducing metallic materials in the layer comprising metal to elemental metal.

17. The method of claim 16, wherein reducing the metallic materials in the layer comprising metal to elemental metal facilitates the selectivity.

18. The method of claim 16, wherein exposing the substrate to the organic reactant comprises removing passivation from the layer comprising metal.

19. The method of claim 18, wherein removing the passivation facilitates the selectivity.