Method for producing carbon surface films by plasma exposure of a carbide compound

• US 20060068125A1
• Filed: 09/30/2004
• Published: 03/30/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: Gouri Radhakrishnan
• Original Assignee: Gouri Radhakrishnan
• Inventors: Radhakrishnan, Gouri
• Granted Patent: US 7,241,475 B2
• Time in Patent Office: Days
• US Class Current: 427/569
• CPC Class Codes: B81B 3/0075 For improving wear resistance
• CPC Class Codes: B81C 1/0038 Processes for creating layers of materials not provided for in groups B81C1/00357 - B81C1/00373
• CPC Class Codes: B81C 2201/0181 Physical Vapour Deposition [PVD], i.e. evaporation, sputtering, ion plating or plasma assisted deposition, ion cluster beam technology
• CPC Class Codes: C04B 2235/96 Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• CPC Class Codes: C04B 2235/9692 Acid, alkali or halogen resistance
• CPC Class Codes: C04B 35/5607 based on refractory metal carbides
• CPC Class Codes: C04B 35/5611 based on titanium carbides
• CPC Class Codes: C04B 35/5622 based on zirconium or hafnium carbides
• CPC Class Codes: C04B 35/5626 based on tungsten carbides
• CPC Class Codes: C04B 35/565 based on silicon carbide

Abstract

Reactive halogen-ion plasmas, having for example, generating chloride ions, generated from low-pressure halogen gases using a radio-frequency plasma are employed for producing low-friction carbon coatings, such as a pure carbon film, at or near room temperature on a bulk or thin film of a compound, such as titanium carbide.

Claims

1. A method for creating a resultant surface film comprising a second constituent in a compound comprising a first constituent and the second constituent, the method comprising steps of,

creating the compound comprising the first and second constituents, the second constituent is an elemental constituent for forming the resultant surface film,

creating a plasma comprising an ionic specie, and

exposing the compound to the ionic specie that reacts with the first constituent of the compound for creating a volatile product comprising the first constituent and the ionic specie and for creating a product comprising the second constituent forming the resultant surface film on a remainder of the compound.

2. The method of claim 1 wherein, the ionic specie is a halogen species.

3. The method of claim 1 wherein, the compound is a metal compound.

4. The method of claim 1 wherein, the ionic specie is a chloride.

5. The method of claim 1 wherein,

the exposing step is conducted at room temperature.

6. The method of claim 1 wherein,

the metal compound is a metal carbide.

7. The method of claim 1 wherein,

the compound is a carbide selected from the group consisting of TiC, SiC, WC, TaC, ZrC, VC, HfC, NbC, SeC₂, and Mo₂C.

8. The method of claim 1 wherein,

the exposing step is a plasma exposing step.

9. The method of claim 1 wherein,

the ionic species is a halogen selected from the group consisting of Cl, F, and Br.

10. The method of claim 1 wherein,

the first constituent is an elemental constituent.

11. The method of claim 1 wherein,

the first constituent is an elemental constituent of Ti, and the second elemental constituent is C.

12. The method of claim 1 wherein,

the exposing step is processed at 85 mtorr.

13. A method for creating a resultant surface film comprising a second constituent in a compound comprising a first constituent and the second constituent, the method comprising steps of,

creating the compound comprising the first and second constituents, the first and second constituents are first and second elemental constituents, the second constituent is an elemental constituent for forming the resultant surface film, the first constituent and the resultant surface film are pure carbon,

creating a plasma comprising an ionic specie, and

exposing the compound to the ionic specie that reacts with the first constituent of the compound for creating a volatile product comprising the first constituent and the ionic specie and for creating a product comprising the second constituent forming a resultant surface film on a remainder of the compound.

14. The method of claim 13 wherein,

the ionic species is ionic chloride,

and the second elemental constituent is titanium.

15. The method of claim 13 wherein,

the exposing step is processed at 85 mtorr.

16. the method of claim 13 wherein,

the exposing step is processed at 40°

C.