DIAMOND FILM FORMATION METHOD AND FILM FORMATION JIG THEREOF

Abstract

A diamond film formation method includes forming, in a composite of a metal material and a semiconductor material, diamond nuclei on a surface of the metal material at a temperature below 650° C. in a first mixed gas containing at least carbon and hydrogen, and growing the diamond nuclei formed in the composite at a temperature below 750° C. in a second mixed gas containing at least carbon and hydrogen to form a diamond film.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIGS. 1A and 1B are perspective views showing forms of film formation target base materials used in the present invention;

FIGS. 2A and 2B are sectional views along the lines IIA-IIA and IIB-IIB of FIG. 1;

FIG. 3 is a perspective view of a film formation jig used in a diamond film formation method of the present invention;

FIG. 4 is a sectional view along the line IV-IV of FIG. 3;

FIG. 5 is a sectional view concerning the film formation jig wherein a tubular metal material 1a shown in FIG. 1 is housed in an opening 12a of a holder 12;

FIG. 6 is a schematic diagram showing how a diamond film is formed when the formation of the diamond film is carried out in a configuration according to the present invention;

FIG. 7 is a schematic diagram showing how a diamond film is formed in a situation where plasma CVD is carried out without using the holder 12 and a mask member 13;

FIG. 8 is a schematic diagram showing how a diamond film is formed in a situation where the plasma CVD is carried out without using the mask member 13;

FIG. 9 is a schematic diagram showing how a diamond film is formed when an upper end of the metal material la is exposed in a reaction space;

FIG. 10 is a perspective view showing another form of the film formation target base material used in the present invention;

FIG. 11 is a perspective view showing another form of the film formation jig used in the diamond film formation method of the present invention;

FIG. 12 is a schematic sectional view showing one example of a discharge lamp cold cathode produced by use of the metal material manufactured using the diamond film formation method;

FIG. 13 is a schematic sectional view showing one example of a discharge lamp cold cathode produced by use of the metal material manufactured using the diamond film formation method;

FIG. 14 is a conceptual diagram of a cold cathode discharge lamp when a cold cathode 20b shown in FIG. 13 is used as an electrode;

FIG. 15 is a conceptual diagram for explaining the diamond film formation method of the present invention;

FIG. 16 is a conceptual diagram for explaining the diamond film formation method of the present invention; and

FIG. 17 is a conceptual diagram for explaining the diamond film formation method of the present invention.

Claims

1. A diamond film formation method comprising: forming, in a composite of a metal material and a semiconductor material, diamond nuclei on a surface of the metal material at a temperature below 650° C. in a first mixed gas containing at least carbon and hydrogen; andgrowing the diamond nuclei formed in the composite at a temperature below 750° C. in a second mixed gas containing at least carbon and hydrogen to form a diamond film.

2. The method according to claim 1, wherein the diamond film is formed at an air pressure higher than an air pressure in said forming the diamond nuclei.

3. The method according to claim 1, wherein the first mixed gas contains methane gas and hydrogen gas.

4. The method according to claim 1, wherein the second mixed gas contains methane gas and hydrogen gas.

5. The method according to claim 4, wherein the second mixed gas further contains at least one selected from the group consisting of trimethyl borate, diborane and trimethylboron.

6. The method according to claim 1, wherein the second mixed gas contains a mixed gas of either acetone or methyl alcohol and hydrogen gas.

7. The method according to claim 6, wherein at least one selected from the group consisting of trimethyl borate, diborane and trimethylboron is further introduced into the second mixed gas.

8. The method according to claim 1, wherein the metal material contains at least one selected from the group consisting of molybdenum, tungsten, cobalt and nickel.

9. A diamond film formation method comprising: by providing a semiconductor material on an opening edge on one surface of a metal material in which an opening is formed, forming diamond nuclei on an interior surface of the opening at a temperature below 650° C. in a first mixed gas containing at least carbon and hydrogen; andgrowing the diamond nuclei formed on the metal material at a temperature below 750° C. in a second mixed gas containing at least carbon and hydrogen to form a diamond film.

10. The method according to claim 9, wherein the diamond film is formed at an air pressure higher than an air pressure in said forming the diamond nuclei.

11. The method according to claim 9, wherein the first mixed gas contains methane gas and hydrogen gas.

12. The method according to claim 9, wherein the second mixed gas contains methane gas and hydrogen gas.

13. The method according to claim 12, wherein the second mixed gas further contains at least one selected from the group consisting of trimethyl borate, diborane and trimethylboron.

14. The method according to claim 9, wherein the second mixed gas contains a mixed gas of either acetone or methyl alcohol and hydrogen gas.

15. The method according to claim 14, wherein at least one selected from the group consisting of trimethyl borate, diborane and trimethylboron is further introduced into the second mixed gas.

16. The method according to claim 9, wherein the metal material contains at least one selected from the group consisting of molybdenum, tungsten, cobalt and nickel.

17. A film formation jig comprising: a support table;a holder mounted on the support table and having at least one first opening; anda mask member mounted on the holder and having a second opening with an inside dimension shorter than an inside dimension of the first opening.

18. The film formation jig according to claim 17, wherein the support table is formed of a metal containing at least one selected from the group consisting of molybdenum, tungsten, cobalt and nickel.

19. The film formation jig according to claim 17, wherein the holder and the mask member are formed of a semiconductor material.