JP2898520B2 - Method for producing nitrogen-containing carbon film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a nitrogen-containing carbon film. More specifically, the present invention relates to a new method for producing a nitrogen-containing graphite-like carbon film, which can provide a highly functional thin film useful in the fields of electronics, biomaterials, and the like.

[0002]

2. Description of the Related Art Conventionally, in the fields of electronics, biomaterials, and the like, highly functional thin films have been studied energetically, and the creation of highly functional thin films having new physical properties has been promoted. The expectation of is put. As one of the highly functional thin films having such new physical properties, a carbon thin film in which different atoms are intercalated and a graphite thick film in which some carbon atoms are replaced by different atoms are attracting attention.

[0003] Fundamental research has been conducted on the physical properties of this heteroatom-substituted carbon film, particularly a graphite-like carbon film. Until now, this type of heteroatom-substituted graphite-like carbon film has been characterized by boron-substituted graphite (BxC) and BN-substituted graphite (BxCyN).
Have been reported.

For example, regarding BN-substituted graphite
Is BCl_Three/ CCl_Four/ N_Two/ H _TwoAt high temperature (2000
° C) or BCl_Three/ CH_ThreeCN at 800 ℃
And in graphite under high temperature and high pressure
It has been reported that B is diffused. But
The conventional heteroatom-substituted graphite-like carbon film
Generally formed by synthesis reaction at high temperature and pressure
Therefore, it is perfectly suitable for the production of other kinds of heteroatom-substituted thin films
There is no problem. In addition, anti-
However, if a corrosive gas such as HCl is generated,
Of corrosive gas as a reaction by-product.
Equipment must be able to withstand
Is disadvantageous in that the equipment for
Was.

[0005] For this reason, the fact is that even with the conventional technology, the production of a graphite-like carbon film in which another heteroatom such as nitrogen is substituted has not been achieved. The present invention has been made in view of the above circumstances, and has as its object to solve the drawbacks of the conventional method and to provide a new method for producing a graphite-like carbon film containing nitrogen as a hetero atom. .

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and is characterized in that a nitrogen-containing cyclic organic compound is subjected to chemical vapor deposition. In other words, the present invention is characterized in that chemical vapor deposition (CVD) is performed without employing a high-temperature and high-pressure synthesis method as in the prior art and without generating corrosive compounds such as HCl as a reaction by-product. There is.

In this case, as the raw material, an appropriate nitrogen-containing cyclic organic compound such as pyrrole, imidazole, pyridine, piperidine, triazole or tetrazole can be used. And these raw materials do not contain an element such as chlorine which generates a corrosive compound such as HCl. In the reaction, an inert gas such as Ar, He, Ne or the like which is difficult to react is preferably used as a carrier gas. The reaction temperature is usually 600 to 100
A temperature of about 0 ° C is employed. The reaction is preferably carried out under normal pressure and reduced pressure.
/ Sec is preferable. Various solids, for example, quartz, glass, Ni, Pt, Si, and others are appropriately used as the substrate.

Of course, in the present invention, thermal CVD
Various methods such as a CVD method, a low pressure CVD method, a plasma CVD method, and a photo CVD method can be used. Hereinafter, the present invention will be described in more detail with reference to Examples.

[0009]

EXAMPLE In a quartz reaction tube, a cyclic nitrogen-containing heterocyclic compound as a raw material was vaporized while controlling the temperature, and introduced into a reaction region on a substrate by a carrier gas (Ar or the like) to form a thin film on the substrate. Pyrrole, which is a cyclic hetero compound, was used as a raw material, Ar was used as a carrier gas, and the flow rate was 300 cc / min. Reaction temperature is 600,75
0,800,1000 ° C.

FIG. 1 is a schematic view of a thin film forming apparatus used in this embodiment. A Ni substrate and pyrrole as a raw material were placed in a quartz tube, the substrate was heated to a predetermined temperature by a furnace, and the raw material pyrrole was heated to a vaporization temperature by a heater, and Ar gas was introduced into the quartz tube. One hour later,
At each of the above reaction temperatures, a thickness of about 1-5
A μm gray thin film was obtained.

When the thin film formed at each reaction temperature was analyzed by X-ray diffraction, a graphite-like layered structure was confirmed in the film formed at 750 ° C. or higher. That is, the intensity by the X-ray diffraction was as shown in FIG. 2, and the X-ray diffraction d value obtained therefrom was as shown in Table 1. In the film formed at a reaction temperature of 600 ° C., no X-ray diffraction peak was observed and no graphite was generated, whereas at 750 ° C. or more, a lattice spacing d value of ~ 3.35 A was obtained, and the graphite-like structure was obtained. It was found that a film was formed. When the half width of X-ray diffraction is 750 ° C., 1.
It was confirmed that the crystallinity was still slightly disordered with 0 deg, and the half width was reduced and the crystallinity was improved when the deposition sensitivity was increased.

Further, the resulting thin film is subjected to X-ray photoelectron spectroscopy (XPS) to determine the N concentration, C energy state,
And the N energy state was confirmed. As illustrated in Table 1, when the reaction temperature is 800 ° C., the N concentration is 1 which is the maximum.
The N concentration decreased as the reaction temperature increased to 5 atm%, and the N concentration decreased as the reaction temperature decreased.

From this, when the C / N of the thin film formed at each reaction temperature was determined, as shown in Table 1,
C / N of the thin film formed at 750 ° C. was 4.6, and C / N of the thin film formed at 750 ° C. was 13.8.

[0014]

[Table 1]

Further, when the C _1s spectrum is used, the intensity of each binding energy analyzed by X-ray photoelectron spectroscopy (XPS) is 284.5 eV, which is close to that of graphite, as exemplified in FIG. In energy, a peak of the intensity was seen. FIG.
It is an example of the spectrum of _1s .

In the same manner as in the above example, vapor deposition was carried out using imidazole, triazole, tetrazole, pyridine and pyrimidine as raw materials instead of pyrrole. As in the case of pyrrole, a nitrogen-containing film having a lattice spacing similar to graphite was obtained.

[0017]

As described above in detail, according to the present invention, a nitrogen-containing graphite-like carbon thin film can be formed.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a thin film forming apparatus according to an embodiment of the present invention.

FIG. 2 is a relationship diagram showing a relationship between an X-ray diffraction angle and intensity in an example of the present invention.

FIG. 3 shows a binding energy (C) according to an embodiment of the present invention.
FIG. 3 is a relationship diagram showing the relationship between _IS ) and the intensity at each temperature.

FIG. 4 shows the binding energy (N
FIG. 3 is a relationship diagram showing the relationship between _IS ) and the intensity for each temperature.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masako Yudazaka 5-8-4 -202 Minamiikuta, Tama-ku, Kawasaki City, Kanagawa Prefecture (72) Inventor Rie Kikuchi 2-1-6-303, 303, Tsukimino, Yamato-shi, Kanagawa Prefecture 72) Inventor Yoshimasa Oki 3-30-2 Ohnodai, Sagamihara City, Kanagawa Prefecture (72) Inventor Susumu Yoshimura 529-18, Kamoshida, Midori-ku, Yokohama-shi, Kanagawa Prefecture (58) Field surveyed (Int.Cl. ⁶ , DB name) C23C 16/26

Claims (2)

(57) [Claims] 1. A method for producing a nitrogen-containing carbon film, comprising producing a graphite-like nitrogen-containing carbon film by chemical vapor deposition using a nitrogen-containing cyclic organic compound as a raw material. 2. The method according to claim 1, wherein a raw material not containing an element that generates a corrosive compound such as chlorine is subjected to chemical vapor deposition.