JP3281354B2 - Method for producing diamond-like 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 carbon or a coating containing carbon as a main component having a hydrophilic property and a specific resistance of 5 × 10 ¹³ Ωcm or less. The present invention, when forming this on a light-transmitting member such as glass, has a light-transmitting property on this member,
The present invention relates to a member having a multilayer structure in which a silicon nitride film having adhesiveness to a member is formed, and carbon or a film containing carbon as a main component is formed thereon. According to the present invention, trivalent or pentavalent impurities are added together with hydrogen or fluorine to a protective coating containing carbon or carbon as a main component to control the degree of hydrophilicity, control Vickers hardness, and control electric conductivity. They want control.

[0002]

2. Description of the Related Art In general, in a plasma CVD method, a method of forming a film in a plane on a substrate having a flat surface is considered to be industrially effective. Furthermore, a method of forming a film with a sputtering effect while using a plasma CVD method is also known. U representative examples in which carbon films - For the coating, "complex and a manufacturing method thereof having a carbon coating" patent application according to the present invention's application (Japanese Patent Application No. Sho 56-14693 0 1981 September 17 Application) are known.

However, these are of a parallel plate type using only a pair of electrodes, and two output terminals derived from one high-frequency power source are connected to each electrode, and a substrate is connected to one electrode (cathode side). Is provided, and a carbon film is formed on the upper surface of the flat surface using a self-bias generated by itself.

[0004]

In order to use one such high-frequency power source, in a parallel plate type plasma reaction method, a substrate is arranged in close contact with an electrode on one side of the electrode, and a substrate is provided on the upper surface thereof. Plasma CVD is performed. for that reason,
Even if mass production is required, the electrode is simply made to have a large area, and the film to be formed is one in which only one film is treated on one electrode surface, and thus the productivity is poor. Further, it is difficult to apply a bias independently to the substrate or the member, and it is difficult to find an optimum process condition for forming a thin film. For this reason, large capacity
A method for forming a film on many members at once in space is required
Was used.

Further, the present invention provides a method for protecting a member surface.
To form a film containing carbon or carbon as a main component
In particular, carbon or carbon-based coatings on members
With good adhesion with a multilayer film without damaging the substrate
Provide the law. The present invention has been made for such a purpose.

[0006]

SUMMARY OF THE INVENTION The present invention provides a member on which such diamond-like carbon (DLC) is formed and a method for producing the same. One end and the other end of a reaction space for plasma CVD are provided. A pair of electrodes (first and second electrodes) are disposed apart from each other. Further, it has independent electromagnetic energy supply means and a matching box. And it has a phase adjuster for mutually controlling the phases of the electromagnetic energy supplied to the respective electrodes via the matching box.

[0007] A large power of KW level is supplied to the reaction space by using the electromagnetic energy generated from each electrode, and the phase of each electrode is controlled to generate a plasma having a synergistic effect in the reaction space. is there.

A third electrode for applying a DC or AC bias is provided in this space as needed. A substrate having a surface to be processed in a space (plasma space) between the pair of electrodes,
The member is arranged using the holder. The reaction space is evacuated and a reactive gas is supplied. Electromagnetic energy of a predetermined electric power and frequency is supplied to each of the pair of electrodes via an electromagnetic energy supply unit and a matching box in order to convert the reactive gas into plasma. Each of these electrodes has a phase of approximately 180 ° or approximately 0 with respect to ground.
° different high-frequency voltages are applied from the respective high-frequency power supplies, and are adjusted and controlled by the phase adjuster so that symmetrical or in-phase alternating voltages are applied to each other.

As a result, substantially one high-frequency alternating voltage is combined, and a large power of KW level is applied to the plasma space to induce high-frequency plasma for completely decomposing and ionizing the reactive gas. Further, the other end of each high-frequency power supply is grounded.

[0010] In the case of further generation, a direct current (DC bias voltage from itself or from the outside) or an alternating voltage (AC bias voltage) is applied across the base or member. In the case of the self-DC bias method, ions accelerated on one electrode side by the second alternating voltage sputter on the formation surface of the member, and strongly form or etch the formation surface on the member.

When the first alternating voltage is applied to the respective electrodes via the independent electromagnetic energy supply means and the matching box, the first alternating voltage is approximately 0 °, ie, 0 ± 30 °.
Within 180 ° or 180 ± 30 °, the latter, ie 180 ± 30 °, is required to spread uniformly over the entire reaction space.
Within 180 ° (approximately 180 °). Further, when the phase degree was within 90 ± 30 °, the plasma was deformed particularly on one electrode side.

This is a phase in which ions are largely moved from one electrode to the other electrode and from the other electrode to one electrode in the reaction space by using both electrodes, so that the space is made wider and plasma is generated. It is estimated to exercise. As the plasma CVD of the present invention, a case of carbon or a film containing carbon as a main component, that is, a DLC (diamond-like carbon film) will be described.

As the formation of this thin film, ethylene (C ₂ H
_4), methane (CH _4), acetylene (C ₂ H _2), carbon fluoride (C ₂ F
₆ , C ₃ F ₈ ) or a carbon fluoride gas such as carbon fluoride or carbon fluoride such as CHF ₃ , H ₂ C ₃ F ₆ , H ₃ CF, CH ₂ F _2. , Plus trivalent or 5
Additive, typically diborane (B
₂ H ₆ ), boron fluoride (BF ₃ ), ammonia (NH ₃ ), and nitrogen fluoride (NF ₃ ) were added. The content of the trivalent or pentavalent additive in the formed film was 0.1 to 10 atomic%. At this time, 5 to 30 atomic% of hydrogen or fluorine was added.

Thus, a CC bond similar to diamond having an SP ³ orbit is formed, and the specific resistance (specific resistance) is 1 × 10 ⁶
5 × 10 ¹² Ωcm, typically 1 × 10 ^{7 to} 5 × 10 ¹¹ Ωcm, Vickers hardness 700 to 5000 Kg / mm ² , and optical energy bandwidth (referred to as Eg) of 1.0 eV or more. Formed a film having properties similar to those of translucent diamond in the visible region with 1.5-5.5 eV.

In forming a film by the method of the present invention, a reaction between C ₂ F ₆ and NH ₃ + H ₂ or a reaction between C ₂ F ₆ and B ₂ H ₆ + H ₂ having a halogen element such as fluorine from an initial state. , Using nitrogen (pentavalent additive) or boron (trivalent additive) simultaneously in addition to the carbide gas during plasma CVD,
A multi-layer composite film having a hydrophilic surface and having a uniform concentration gradient in the thickness direction and containing carbon as a main component or controlling the presence or absence of additives may be produced. In addition, fluorine resistance
By using a silicon nitride film, which is a body coating, as a base material,
Is not damaged by fluorine.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method of the present invention will be described below with reference to the drawings.

[0017]

Embodiment 1 FIG. 2 shows an outline of a plasma processing apparatus for performing a method of forming or etching a thin film on a substrate or a member by a plasma reaction method. In the drawing, a reaction vessel (7) of a plasma reactor is separated from the outside by a gate valve (9). In the gas system (30),
Hydrogen or argon as a carrier gas is converted from (31) to hydrocarbon gas as a reactive gas, for example, methane (CH ₄ ), ethylene (C ₂ H ₄ ) is converted from (32) to fluorinated as a carbon fluoride gas. Carbon (C ₂ F ₆ , C ₃ F ₈ ) is converted from trivalent or pentavalent gas B ₂ H ₆ or NH ₃ from (33) to disilane (34).
(Si ₂ H ₆ ) is converted from (35) to nitrogen fluoride or oxygen, which is an etching gas for the reaction vessel, from (36) through a valve (28) and a flow meter (29) into the reaction system (50). Through the nozzle (25).

[0018] With the introduction of hydrogen and hexafluoride two carbon (C ₂ F _6), hydrogen abstraction fluorine, remaining diamond-like carbon film (DLC both having a large number of SP ³ bonding fluorine is added by CF bonds However, in the present invention, including a DLC to which an additive is added, carbon or a film containing carbon as a main component can be formed. Disilane (Si ₂ H ₆ ) can be introduced from (35) and ammonia (NH ₃ ) can be introduced from (34) to cause a plasma CVD reaction to form a silicon nitride film.

The first and second electrodes (3-1), (3-1),
(3-2) is made of aluminum metal mesh.
Each of these electrodes has first and second electromagnetic energy supply means (15-1) and (15-2). An alternating voltage of 1 to 100 MHz, for example, a high-frequency voltage of 13.56 MHz is generated from a supply means as each power supply, and a matching box (16-1) configured by LCR and using the electromagnetic energy to match the impedance in the reaction vessel with impedance. ) And (16-2).

The matching terminal (4-
Electromagnetic energy is supplied to the electrodes (3-1) and (3-2) via (1) and (4-2). The first and second power supplies (15-1), (15
-2) In principle, the same waveform of the same frequency is used, but a fixed-size waveform may be used. The phase of each power supply is adjusted by the phase adjuster (2
6) are controlled within 180 ° ± 30 ° from each other.

The reactive gas is discharged downward from the nozzle (25). The frequency of the DC power supply (17-2) of the bias voltage and the frequency of the second alternating voltage power supply (17-1) are supplied by bias means (17) having a frequency of 10 Hz to 100 KHz. This bias is supplied to the substrate or member when the switch is on .

Thus, a plasma is generated in the reaction space (8). The exhaust system (25) exhausts unnecessary gas through a pressure adjusting valve (21), a turbo molecular pump (22), and a rotary pump (23). These reactive gases have a reaction space (8) of 0.001 to
1.0 torr For example, 0.05 torr.

[0023] In such a space, adding a first high frequency voltage of 0.5 ~50KW (per unit area 0.005 ~5W / cm ²⁾ for example 1 KW (high energy per unit area 0.1W / cm ^2). Further, by applying an AC bias by the second alternating voltage, -50 to -600 V (for example, the output is
The negative self-bias voltage of (W) was applied, and the reactive gas accelerated by the negative self-bias voltage was formed on the substrate or member while being sputtered, and a dense film could be formed. .

The reactive gas is, for example, a mixed gas of ethylene and carbon fluoride. The ratio is C ₂ F ₆ / C ₂ H ₄ = 1/4 to 4 /
1 and typically 1/1. By changing this ratio, the transmittance and the specific resistance can be controlled. The temperature of the substrate or member (1) is maintained at room temperature to 150 ° C., typically at room temperature without external heating. Thus, the specific resistance on the surface to be formed is 1 × 10 ^{6 to} 5 × 10 ¹³ Ωcm,
It has an optical energy band width of 1.0 to 5.5 eV and can be formed in close contact with an organic resin or other solid inorganic material.

[0025] A carbon or carbon-based coating containing fluorine and hydrogen having an amorphous structure or a crystal structure that is transparent to visible light and containing 0.1 to 8 µm, for example, 0.1 to 8 µm.
5 μm (flat portion) and 1-3 μm (convex portion). The deposition rate was 100-1000 ° / min.

Thus, on a glass plate, an organic resin material, and other members, a film containing carbon as a main component, in particular, containing not more than 30 atomic% of hydrogen or fluorine in carbon,
It was possible to form a hydrophilic carbon film in which boron or nitrogen was mixed at a concentration of 0.3 to 10 at%.

A first carbon made of only ethylene is provided on the organic material to a thickness of 100 to 2000 mm, and further a C ₂ F ₆
Using hydrogen, hydrogen and ammonia, it was possible to form a multi-layered coating mainly composed of hydrophilic carbon to which fluorine, nitrogen and hydrogen were added.

Example 2 This example is an example in which a film containing carbon as a main component was formed on a main part of an organic material as shown in FIG. 1 using the apparatus used in Example 1. In FIG. 1 (A), an OPC (organic photosensitive conductor) drum (1) having an organic resin as a base on an aluminum cylinder is used, and a DLC film as a photoconductor or a protective film is formed thereon. (45)
Is formed.

1 (A) and 1 (B), the plastics substrate (1) is lightweight, and has a thickness of 0.01 to 0.1 μm using ethylene and hydrogen to improve the adhesion on the substrate. Formed. Further, a film having a specific resistance of 1 × 10 ^{6 to} 5 × 10 ¹³ Ωcm, preferably 1 × 10 ^{7 to} 5 × 10 ¹² Ωcm is formed thereon by using a mixed gas of C ₂ F ₆ , NH ₃ and H _2. A carbon film having hydrophilicity was formed to a thickness of about 2 μm. Thus, a coating containing carbon as a main component to which 4.5 atomic% of nitrogen, 10 to 30 atomic% of fluorine and hydrogen were added was produced on the OPC drum by the method of the present invention.

Embodiment 3 This embodiment is an example in which silicon nitride is formed as a coating for a base material. As a reactive gas
In FIG. 2 , disilane (Si ₂ H ₆ ) / NH ₃ is supplied from (35) and ammonia (NH ₃ ) is supplied from (34), and (Si ₂ H ₆ ) / NH 3 = 1 /
It was 3 to 1/10. Example 1 without external heating
Similarly, high frequency was applied at a pressure of 0.05 torr. Then, it became possible to form a silicon nitride film on these upper surfaces at a film forming rate of 100 μm / min.

"Embodiment 4" This embodiment is shown in FIG. The plasma processing apparatus of FIG. 2 was used in the same manner as in the example. Then, place the plate-shaped substrate holder in the plasma space.
(8) Substrate (1) disposed in and having a formation surface on both sides
This is an example in which a coating is formed in multiple layers, and there is a glass plate as the substrate. This glass sheet is a front window, a side mirror, a side window, a rear window of a car, a motorcycle, an aircraft, or a ship, or a window of a house, and is a surface side of the window which is exposed to the outside air.

First, the silicon nitride film shown in Example 3 was formed on this substrate. The reaction vessel was further excluded without exposing the reaction vessel to outside air (particularly oxygen).
As shown in FIG.
It was formed to a thickness of 5 μm, for example, 0.5 μm.

In the present invention, in particular, the coating mainly composed of carbon or carbon to which fluorine is added in addition to the trivalent or pentavalent additive has a hydrophilic property and prevents adhesion of dust due to generation of static electricity. To prevent this, the specific resistance is 1 × 10 ⁶ -5 ×
10 ¹³ Ωcm, particularly preferably 1 × 10 ⁷ to 1 × 10 ¹¹ Ω
cm.

In this embodiment, the glass is made of silicon oxide, contains oxygen, and easily reacts with the fluoride gas. Therefore, before forming the DLC, the glass is formed as a light-transmitting and dense buffer layer having oxygen resistance. A silicon nitride film (45-1) having good properties was formed. Then, a carbon film to which fluorine was added or a film (45-2) containing carbon as a main component was laminated on silicon nitride having fluorine resistance than silicon oxide. Longitudinal sectional view of FIG. 1 (C) is not a front window only, side window, mirror - may be a surface.

FIG. 1 (E) shows an example in which it is formed on a curved surface. The present invention is excellent because these materials have a strong windbreak in actual use, and are liable to collide with dust of mineral substances, and as a result, devitrification and turbidity are easily generated by abrasion.

Example 5 In an example of the present invention, disilane and ethylene were introduced into a plasma atmosphere as base materials to form silicon carbide (Si _x C _{1 -x} 0 <X <1). A film composed mainly of carbon or carbon was formed thereon. Then, the optical energy bandwidth of this silicon carbide is 1.5 to 2.
Since it was 5 eV, a yellow semi-transparent base material could be obtained. It was also very effective in improving the adhesion of the carbon coating.

[0037] "Example 6" This embodiment is in the form of FIG. 1 (D). The apparatus used in Example 1 was a silicon nitride film as a base material, and a hydrophilic carbon film was formed thereon as in Example 4. In the layer shown in FIG. 1 , the substrate holder is formed in a plate shape, and the substrates (11) and (11 ') are provided on both surfaces thereof. As a result, on each of the substrates (11) and (11 '), only one side has a silicon nitride film (45-1), (45-1') and a carbon or carbon-based film (45 -2) and (45'-2) were laminated. As a result, a carbon film could be formed on glass or the like in close contact with the same as the carbon film (4). The productivity was doubled by forming only one surface on which rain was applied. Others are the same as the fourth embodiment.

Example 7 In this example, the apparatus used in Example 1 was used. In FIG. 2 , only oxygen (O ₂ ) or nitrogen fluoride (NF ₃ ) is introduced to remove the coating on the substrate or member or the reaction vessel or holder by 100 to 300 mm.
/ Min speed. In this embodiment, the material to be etched (etched with a plasma oxygen) coating mainly containing carbon or carbon, a silicon nitride (being etched by the plasma of the NF _3).

[0039]

According to the method of the present invention, it has become possible for the first time to produce a protective film having electric conductivity and a hydrophilic surface. In particular, dust accumulates on a light-transmitting surface such as a window, and when the surface tension is high on a rainy day, even if the user looks through the window from the inside through the window, the outside cannot be seen well due to diffuse reflection of raindrops. In the present invention, a hydrophilic carbon or a film containing carbon as a main component is formed on a translucent substrate or a member by eliminating such a defect.

In particular, when the light-transmitting substrate is a glass member such as silicon oxide, the film that can be formed only by replacing the reactive gas in the same reactor is a silicon nitride film and carbon or carbon. Coatings as components, both of which are non-oxide materials. Further, it is effective to use a silicon nitride film, which is a fluorine gas resistant film, as a base material because the substrate is not damaged by fluorine. At the time of film formation, the film formation temperature was formed at room temperature to 150 ° C., which was almost the same temperature, and the productivity was improved.

[Brief description of the drawings]

FIG. 1 shows an example in which a film is formed on a substrate or a member of the present invention, and an essential part thereof.

FIG. 2 shows an outline of a plasma apparatus of the present invention.

[Explanation of symbols]

 1 Substrate 45 DLC

Continuation of the front page (72) Inventor Junichi Takeyama 398 Hase, Atsugi-shi, Kanagawa Prefecture Examiner in Semiconductor Energy Laboratory Co., Ltd. Naoyuki Miyazawa (56) References JP-A-63-219586 (JP, A) JP-A-63-210010 JP-A-63-153275 (JP, A) JP-A-63-145776 (JP, A) JP-A-63-140083 (JP, A) JP-A-63-97961 (JP, A) JP-A 62-270774 (JP, A) JP-A 62-177189 (JP, A) JP-A 62-157602 (JP, A) JP-A 62-150356 (JP, A) JP-A 62-133068 ( JP, A) JP-A-62-46514 (JP, A) JP-A-61-106494 (JP, A) JP-A-61-30671 (JP, A) JP-A-60-230983 (JP, A) JP-A-60-170234 (JP, A) JP-A-58-185418 (JP, A) JP-A-58-126972 (JP, A) JP-A-58-92218 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C23B 16/00-16/56 B32B 9/00

Claims (11)

(57) [Claims] A diamond-like carbon film containing nitrogen is formed on a surface of a member by forming a plasma of a reactive gas to form a base coat on the surface of the member, and forming a plasma of a fluorocarbon gas and an ammonia gas on the base coat. Forming a diamond-like carbon film. 2. A diamond-like carbon film containing nitrogen on a surface of a member by forming a plasma of a reactive gas to form an undercoat on the surface of the member, and forming a plasma of a hydrocarbon gas and a nitrogen fluoride gas on the undercoat. Forming a diamond-like carbon film. Forming a plasma of a reactive gas to form a base coat on the surface of the member; forming a plasma of a fluorocarbon gas and a nitrogen fluoride gas to form a diamond containing nitrogen on the base coat; A method for producing a diamond-like carbon film, comprising forming a carbon film. 4. The method for producing a diamond-like carbon film according to claim 1 , wherein the reactive gas includes an ammonia gas. 5. The method for producing a diamond-like carbon film according to claim 1 , wherein the undercoat is a silicon nitride film. 6. The method for producing a diamond-like carbon film according to claim 1 , wherein the reactive gas includes a hydrocarbon gas. 7. The method for producing a diamond-like carbon film according to claim 1 , wherein a surface of said member is made of an organic resin. Wherein said member is claims 1 to 7, characterized in that an organic resin film provided OPC drum
The method for producing a diamond-like carbon film according to any one of the above. 9. The method for producing a diamond-like carbon film according to claim 1 , wherein a surface of said member is made of an oxide. 10. The specific resistance of the diamond-like carbon film is as follows:
請, wherein it is ^{1 × 10 6 ~5 × 10 13} Ωcm
The method for producing a diamond-like carbon film according to any one of claims 1 to 9 . 11. The method for producing a diamond-like carbon film according to claim 1, wherein the diamond-like carbon film has a Vickers hardness of 700 to 5000 kg / mm ² .