JPS61288069A - Diamond-like carbon film forming device - Google Patents

Abstract

PURPOSE:To improve the wear resistance, insulation characteristic and film forming speed of a film by forming the film of diamond-like carbon on a substrate disposed on a cathode by utilizing the arc discharge of an anode carbon rod as a carbon supply source. CONSTITUTION:Gaseous H2 is introduced into a film forming chamber 1 the inside of which is evacuated to a vacuum. An electric power source 7 is connected between the cathode 4 and the anode 6 to impress DC electricity thereto. An electric power source 11 is connected to the anode 6 consisting of >=1 pairs of carbon bodies 9, 10 which are spaced from each other to discharge the arc. The carbon is gasified and ionized by the arc discharge. The ions are accelerated by the effect of the electric field and are transferred onto the substrate 5 so that the diamond-like carbon film is formed together with hydrogen on the substrate 5.

Description

[Detailed description of the invention] 〔Technical field〕 The present invention relates to a diamond-like carbon film forming apparatus.

[Prior art and its problems]

Various methods have been proposed for producing diamond-like carbon, and some of them have been put into practical use.

Examples include ion brating method and ion beam sputtering method. In ion blating, one airtight film formation chamber is evacuated, hydrocarbon gas such as methane is introduced as a carbon source, and hydrogen gas is introduced to replace dangling bonds, and these gases are thermally decomposed and activated. From now on, diamond-like carbon will be deposited on the substrate to form a film.

The film formation rate by this method is low, usually only about 600 to 800 m/min. This is because chemical decomposition of hydrocarbon gas is used. Furthermore, there is a drawback that the structure of the device becomes complicated.

[Purpose of the invention]

Therefore, an object of the present invention is to provide an efficient film forming apparatus for diamond-like carbon.

Another object of the present invention is to provide a diamond-like carbon film forming apparatus with a simple structure.

[Summary of the invention]

The present invention combines a hydrogen gas source and exhaust means in an airtight film formation chamber, provides a cathode supporting a film formation substrate in the film formation chamber, arranges an anode opposite to the substrate, and disposes these anodes and a film forming apparatus in which a cathode is connected to the positive and negative sides of a power source, respectively, the anode is composed of at least a pair of carbon bodies facing each other, and a power source is connected to the carbon body to cause an arc discharge between them. This is a diamond-like carbon film forming apparatus characterized by:

According to the present invention, since hydrocarbons are not introduced as carbon raw materials, the vacuum in the film forming chamber can be adjusted appropriately.

Further, since a large amount of carbon ions can be formed by arc discharge, the rate of film formation of diamond-like carbon can be increased. Furthermore, since there is less gas flow, the film thickness distribution becomes uniform.

The film forming apparatus of the present invention will be described in detail below with reference to Examples.

[Description of Examples] In this specification, diamond-like carbon refers to carbon that has a diamond structure in minute portions, and is a substance that has a large energy gap Eg representing electrical insulation, and has high hardness. This substance is widely used in electrical insulating films and wear-resistant protective films for electronic devices. It is desirable that diamond-like carbon can be formed into a film as uniform as possible at a high t & film speed.61 The present inventor has discovered that such a request can be met by using arc discharge of a carbon rod as a carbon supply source. .

FIG. 1 shows a schematic diagram of a film forming apparatus of the present invention. The film forming chamber 1 is formed airtight and is connected to a hydrogen gas source via a valve 2. It is also connected to an exhaust pump via a valve 5. A cathode 4 is arranged inside the film-forming chamber 1, and a film-forming substrate 5 is attached to the surface of the cathode 4.An anode 6 with carbon bodies facing each other is arranged at a position facing the substrate 5. An anode 6 and a cathode 4 are connected to the positive and negative sides of a power source 7, respectively. A heater 8 is provided near the substrate 5 and is used to vent gas from the substrate.

The anode 6 is made up of carbon bodies 9.1o arranged opposite to each other, and a power source 11 is connected between these carbon bodies 9.100. The opposing ends of the carbon body 9.10 are preferably one pointed end and the other end. When electricity is applied between carbon bodies 9.10, arc discharge occurs, and the heat causes carbon bodies 9.100
The opposite end evaporates and ionizes. Since the carbon bodies 9,10 are consumable, it is desirable to maintain a constant spacing of the carbon rods with a suitable feeding device.

The amount of carbon vapor increases by increasing the number of carbon bodies. FIG. 2 shows an example of this, in which the metal holder 12
．． 13 and the same number of carbon rods 9, 91, 94 and 10, respectively.
．． 101 and 101 are held, and the distance between them is measured using the rack-binion 14.

Other forms of anode may be used in place of the carbon body.

FIG. 3 shows a carbon anode formed into a disk shape. The circumferential surface of the disc 15 is recessed in a V-shape, and the disc 16 facing this
The circumferential surface has sharp edges.

By gradually rotating both disks in the direction of the arrow as they wear out, the arc discharge gap can always be maintained constant.

In operation, the film forming chamber 1 is sufficiently evacuated by opening the valve 3,
Further, the heater 8 sufficiently vents gas from the substrate 5. Next, valve 2 is opened to introduce H1 gas at a predetermined flow rate, power source 7 is connected between electrodes 4.5 to apply an electric field, and power source 11 is used to connect carbon rods 9.10 (or as shown in FIG. 2 or 5
An arc discharge is formed between the carbon bodies or carbon discs (as shown in the figure). Carbon is vaporized and ionized by the heat of the arc discharge, accelerated by the action of the electric field, transferred onto the i-plate, and forms a diamond carbon film on the substrate together with hydrogen. While the carbon vapor reaches the substrate, or after reaching the substrate, some of the carbon takes in H and gas, and some of the carbon vapor becomes hydrocarbons.

Diamond-like carbon having a diamond structure is thus generated on the substrate 5 in minute portions.

When arc discharge is used, carbon is efficiently vaporized and ionized, so a film formation rate two to three times faster than conventional methods can be obtained.

Also, by adjusting the degree of vacuum, the hardness and optical energy gap can be adjusted over a wide range #! Can do 4 adjustments.

Example Using the film forming apparatus shown in Fig. 1, arc discharge power α2~tox
w, hydrogen pressure 10' to 104 Pa and bias voltage 60
A diamond-like carbon film formation experiment was conducted under 0V conditions. The results are shown in Figures 4.5 and 6. As can be seen from Figure 4, by increasing the arc discharge power (that is, increasing the carbon evaporation rate), the film forming rate can be increased two to three times the conventional rate. Also, Figures 5 and 6
As you can see from the figure, the deposition chamber pressure (hydrogen partial pressure) is 1×104
It can be seen that when the carbon film is increased to a certain level, the hardness Hma (Vickers) and the optical energy gap xi are large, and a diamond-like carbon film with good wear resistance and insulation properties is obtained.Also, since no hydrocarbon is used, the film thickness is uniform. become.

As described above, in the present invention, since the anode is made of a carbon body and carbon atoms are generated by arc discharge, diamond-like carbon with good efficiency and properties can be provided.

4, Fig. 1 is a schematic diagram of the film forming apparatus of the present invention, Fig. 2 is an enlarged view showing the structure of the anode, and Fig. 3 is an enlarged view showing another example of the anode.
FIG. 4 is a graph showing the relationship between arc discharge power and deposition rate, FIG. 5 is a graph showing the relationship between pressure and hardness, and FIG. 6 is a graph showing pressure and optical energy gap.

1:1 & membrane chamber 11’l goose gas valve 3: Exhaust valve 4: Cathode 5: Substrate 6: Anode 7: Power supply 8: Heater 9.10: Carbon body 11: Power supply 12.13: Holder 15% 16: Carbon disk Figure 1 Figure 2 Figure 4 A2D (Electric T-Car (KW)) Figure 6 Wood wax (Pa)-

Claims (2)

[Claims] 1. A cathode is disposed in an airtight film forming chamber connected to a hydrogen gas source and an exhaust means to support a substrate, an anode is disposed facing the substrate, and the anode and cathode are connected to the positive and negative sides of a power source, respectively. A diamond-like carbon film forming apparatus comprising: a diamond-like carbon film forming apparatus, wherein the anode comprises at least a pair of spaced apart carbon bodies, and a power source is connected between the carbon bodies to generate an arc discharge. . 2. 2. The film forming apparatus according to item 1, wherein one of the opposing ends of the carbon body is a pointed end and the other is a recessed end.