JP2006057132A - Plasma cvd system, and method for manufacturing hard carbon film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a hard carbon film on a substrate such as a silicon substrate. <P>SOLUTION: The hard carbon film manufacturing method comprises: a step of arranging a work 3 in a reaction container 2, a step of arranging magnets 15a, 15b on a back side of the work 3 arranged in the reaction container, and of locally forming the magnetic field on the face side of the work 3 and in a vicinity thereof; and a step of introducing raw material gas in the reaction container 2 and generating plasma in the reaction container 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing a hard carbon film based on a plasma CVD method, and a plasma CVD apparatus that can be used for the production.

A hard carbon film such as so-called diamond-like carbon has excellent film characteristics such as high hardness, low friction coefficient, smoothness, and chemically inactive. For this reason, it is used in various applications for the purpose of improving the wear resistance, slidability, corrosion resistance and the like of the substrate.
As a method for producing (depositing) a hard carbon film on the surface of a substrate (material to be treated), a sputtering method, an ion plating method, a plasma CVD method, and the like have been put into practical use. In particular, the plasma CVD method can form a film over a relatively wide area, and a hard carbon film can be coated on a base material made of an insulator such as a resin molded body. Various plasma CVD apparatuses are used for manufacturing a hard carbon film using such a plasma CVD method.
For example, Patent Document 1 describes a method of manufacturing a hard carbon film by an ECR plasma CVD method using electron cyclotron resonance, which is a kind of plasma CVD method.

JP 2002-20870 A

However, the film formation rate of the hard carbon film by the plasma CVD method is slower than other methods. For this reason, development of the film-forming method based on the plasma CVD method which can form a hard carbon film on a base material more efficiently is calculated | required.
The present invention was created to meet such demands, and an object of the present invention is to provide a method for efficiently forming (manufacturing) a hard carbon film on a substrate and a plasma CVD apparatus capable of suitably carrying out the method. And

In order to solve the above-mentioned problems, the present inventor has intensively studied to pay attention to the property that plasma is converged by a magnetic field, and to use these characteristics in an approach different from the conventional one to complete various inventions described below. It came.
The present invention provides a method for producing a hard carbon film on the surface of a material to be treated (base material) based on a plasma CVD method. In this method, a step of disposing a material to be processed in a reaction container, a magnet is disposed on the back surface side of the material to be processed disposed in the reaction container (that is, the surface side opposite to the carbon film forming surface), The method includes a step of locally forming a magnetic field on and near the surface of the material to be treated, and a step of introducing a raw material gas into the reaction vessel and generating plasma in the vessel.

Here, the “hard carbon film” refers to a carbon film having a hardness that can be produced by a plasma CVD method, and is not limited to a specific hardness. Typically, it has a carbon sp ³ bond like natural diamond, and partially has a carbon sp ² bond like graphite. A carbonaceous film generally called diamond-like carbon (DLC) is a typical example included in the hard carbon film here.
In the method disclosed herein, a magnet is arranged on the back side of the material to be treated (opposite the carbon film forming surface), and the surface side of the material to be treated and its vicinity are formed by forming a magnetic circuit having the magnet as a component. A strong magnetic field is formed locally. Accordingly, the plasma density derived from the source gas can be locally increased in the vicinity of the surface of the material to be processed, and as a result, the deposition rate of the hard carbon film can be improved.

Preferably, plasma is generated in the reaction vessel by supplying high-frequency power to the reaction vessel. And the said to-be-processed material is arrange | positioned on the electrode to which this high frequency electric power is applied.
Here, “high-frequency power” refers to power that is supplied from a high-frequency power source and that can generate plasma, typically at a frequency of 1 to 100 MHz. For example, high frequency power of 13.56 MHz, 27.12 MHz, or 40.68 MHz can be given.
According to such a method, plasma can be efficiently generated at high density near the surface of the material to be processed by using high-frequency power.

  Further, as the method disclosed herein, the magnet is particularly preferably arranged such that a magnetic field line loop is formed on the surface of the material to be processed arranged in the reaction vessel. Thereby, the plasma can be confined in the vicinity of the surface of the material to be processed, and the hard carbon film can be efficiently formed. For example, as a preferred embodiment, the magnet is arranged on the back surface side of the material to be processed with at least one S pole and at least one N pole directed to the material to be processed. A method is mentioned.

The present invention also provides a plasma CVD apparatus that can suitably carry out the method disclosed herein. This apparatus includes a reaction vessel into which a source gas can be introduced, a plasma generating means for generating plasma in the vessel, and a product derived from the source gas on the surface of the material to be processed in the vessel. A placement part for placing the material to be treated, and one or more magnets provided on the back side of the material to be treated placed in the placement part, wherein the magnet is locally disposed on the surface side of the material to be treated and in the vicinity thereof And a magnet for forming a magnetic field.
According to the plasma CVD apparatus having such a configuration, the method for producing a hard carbon film disclosed herein can be suitably implemented.
Preferably, the plasma generating means is configured to supply high-frequency power into the reaction vessel, and the arrangement unit includes an electrode to which high-frequency power is applied. With this configuration, a hard carbon film can be efficiently formed (manufactured) on the surface of the material to be processed.

  Hereinafter, preferred embodiments of the present invention will be described in detail. It should be noted that technical matters other than the contents particularly mentioned in the present specification and necessary for the implementation of the present invention can be grasped as design matters of those skilled in the art based on the prior art. The present invention can be carried out based on the technical contents disclosed in the present specification and the common general technical knowledge in the field.

  In the method for producing a hard carbon film of the present invention, a material to be treated is disposed in a reaction vessel for performing plasma CVD, and a magnet is disposed on the back side of the material to be treated, and the surface side of the material to be treated and its surface In this method, a magnetic field is locally formed in the vicinity, a raw material gas is introduced into the reaction vessel in such a state, and plasma is generated in the vessel to efficiently produce a hard carbon film. As long as these are realized, various processes necessary for performing the plasma CVD method can be performed using various known materials and apparatuses.

  The material to be processed that can be applied to the method for producing a hard carbon film of the present invention is a material that can form a carbon film by plasma CVD, and a suitable magnetic field can be formed on the front surface side when a magnet is disposed on the back surface side. Any material and shape can be used without particular limitation. For example, a silicon substrate or other metal substrate, or an alumina substrate or other ceramic substrate can be preferably used as the material to be processed. A nonmagnetic material or a soft magnetic material (for example, a base material made of amorphous metal) can be suitably used as the material to be treated.

As a raw material gas used in the method for producing a hard carbon film of the present invention, a gas having a composition that can be plasma-excited by glow discharge or the like to form (evaporate) a carbon film on the surface of various materials to be used is used without particular limitation. be able to. For example, a simple gas composed of a saturated aliphatic hydrocarbon such as methane, ethane or propane, an unsaturated aliphatic hydrocarbon such as ethylene, acetylene or propylene, or an aromatic hydrocarbon such as benzene, toluene or naphthalene, or the like A gas mixture as a component can be used. Alternatively, hydrogen, nitrogen, oxygen or argon alone or a mixed gas thereof may be added to these carbon source gases.
The method (means) for supplying these source gases into the vessel may be the same as in the conventional plasma CVD method. Typically, the source gas is supplied at a predetermined gas pressure into the reaction vessel that has been depressurized by a vacuum pump or the like. Supply. For example, preferably, after reducing the pressure in the container to about 1.0 × 10 ⁻² Pa or less (for example, 5 to 6 × 10 ⁻³ Pa) before supplying the source gas, the inside of the container is 1 to 100 Pa, preferably The source gas is supplied into the container so as to achieve a low pressure condition of about 5 to 50 Pa (for example, 15 to 25 Pa).

Then, plasma is generated from the raw material gas, and a raw material gas decomposition product (carbon ion, etc.) is vapor-deposited on the surface of a material to be processed (for example, a silicon substrate) disposed in the container, thereby producing a hard carbon film such as DLC. Membrane).
Examples of the plasma generating means include application of high-frequency power and microwave, but it is particularly preferable to use high-frequency power. By using high-frequency power, a hard carbon film can be efficiently formed under relatively low temperature conditions (typically 200 ° C. or less). Typically, by supplying high-frequency power between two electrodes (anode and cathode) equipped in the reaction vessel, a glow discharge is generated in the vessel, the source gas is decomposed by the glow discharge, and plasma is generated. be able to. For example, a high frequency of about 1 to 100 MHz (for example, 13.56 MHz) is typically applied between the anode and the cathode with a power of about 10 W to 50 kW (for example, 10 W to 1000 W, preferably 100 W to 500 W).

In the method for producing a hard carbon film of the present invention, a magnet is arranged on the back side of the material to be treated arranged in the container to form an appropriate magnetic circuit, thereby forming a local magnetic field on the surface of the material to be treated. . As long as this purpose can be realized, the type and shape of the magnet to be used are not limited, and may vary depending on the shape (particularly the shape of the arrangement portion of the material to be processed) and the size of the CVD reaction vessel. Although use of an electromagnet or a permanent magnet is mentioned, use of a permanent magnet is preferable.
Further, it is preferable to configure the magnetic circuit so that a magnetic field loop is formed on the surface side of the material to be processed. For example, a magnetic field line loop is formed on the surface of the material to be processed by arranging the N pole and the S pole directed to the material to be processed close to each other with a suitable distance therebetween, which is suitable for plasma confinement. A closed magnetic field region can be formed.
In this case, the strength (magnetic flux density) of the magnetic field to be formed is not particularly limited, but the magnetic flux density (B _parallel ) in parallel with the material to be processed is at least 0.005 T (Tesla) or more. For example, about 0.01 to 0.2 T is preferable. In particular, a magnetic flux density (B _parallel ) of about 0.03 to 0.1 T is preferable for manufacturing a hard carbon film.

In carrying out the present invention, it is preferable that the magnetic circuit (that is, the magnet) provided on the back side of the material to be processed is configured to be movable. Thereby, the strength of the magnetic field in a predetermined portion on the surface side of the material to be processed can be changed. Alternatively, a region where a magnetic field having a predetermined strength is formed can be moved in the surface direction of the material to be processed.
For example, a magnetic circuit (magnet) can be moved in a vertical direction and / or a horizontal direction on the lower side of the support base while the workpiece is disposed on a fixed support base (typically a cathode electrode). By providing, fluctuations in the strength of the magnetic field (typically can be realized by moving the magnetic circuit (magnet) in the vertical direction that can vary the distance between the workpiece and the magnet), and / or Movement of the magnetic field region in the surface direction of the material to be processed (typically can be realized by horizontal movement of a magnetic circuit (magnet) that can change the relative position of the magnet on the back surface side of the material to be processed). be able to.
Alternatively, while the magnetic circuit is fixedly provided, the support base for the material to be processed may be provided movably. For example, a conventionally known stage system that moves in the X-axis Y-axis direction or further in the Z-axis direction can be used.

  Next, a preferred embodiment of a plasma CVD apparatus capable of implementing the method for producing a hard carbon film based on the plasma CVD method disclosed herein will be described with reference to the drawings. However, it is not intended to limit the hard carbon film manufacturing method and the plasma CVD apparatus of the present invention to the following forms.

FIG. 1 schematically shows a configuration of a plasma CVD apparatus 1 according to the present embodiment. The apparatus 1 is roughly composed of a reaction vessel 2, an arrangement unit 5 that supports the material 3 to be processed inside the reaction vessel 2, and a power supply unit 10 that supplies high-frequency power into the reaction vessel 2. Has been.
The reaction vessel 2 has a cylindrical shape that can be depressurized, and a gas supply pipe connected to various gas supply means (typically a vacuum pump) (not shown) and a raw material gas supply source is provided on a part of the side wall 8 thereof. 7 is provided. Further, another part of the side wall 8 is provided with a gas discharge pipe 9 connected to various gas discharge means (typically a vacuum pump) (not shown).
The side wall 8 of the container 2 is electrically connected to the power supply unit 10 and constitutes an anode in the apparatus 1. By utilizing such a side wall 8, a relatively large area of the anode can be secured. The area of the anode (side wall) 8 in this embodiment is about 6000 cm ² .

The placement unit 5 includes a disk-shaped top plate 14 having a diameter of about 10 cm on which the plate-shaped workpiece 3 can be placed, and a casing 13 provided on the lower surface of the top plate 14. The top plate 14 is configured to be electrically connected to the power supply unit 10 and constitutes a cathode in the apparatus 1. The area of the cathode (top plate) 14 is about 78.5 cm ² . That is, in the apparatus 1 according to the present embodiment, the sizes and positions of the cathode 14 and the anode 8 used for CVD are asymmetric. By arranging such an asymmetric electrode (for example, using a cathode having a smaller area with respect to an anode having a relatively large area), it is easy to increase the local plasma density near the surface of the workpiece 3. Can be realized.

On the other hand, a magnetic circuit including permanent magnets 15 a and 15 b is formed inside the casing 13. As a result, a local magnetic field can be formed on the surface side of the workpiece 3 disposed on the top plate (cathode) 14 and in the vicinity thereof. Further, as shown in the figure, in the present embodiment, the arrangement of the N poles and S poles of the permanent magnets 15 a and 15 b in the casing 13 is devised, and specifically, in the central portion of the disk-shaped top plate 14. Are arranged with a magnet 15b having an N pole directed in the direction in which the material 3 is disposed. On the other hand, an annular magnet 15 a having an S pole directed in the direction in which the workpiece 3 is disposed is disposed along the circumference (outer edge) of the disk-shaped top plate (cathode) 14. As a result, as schematically shown, a magnetic field line loop 23 is formed from a portion near the S pole (circumferential portion of the top plate 14) to a portion near the N pole (the center portion of the top plate 14). By forming a magnetic field with such a magnetic force line loop 23, a space for confining plasma in a high density state can be formed in the vicinity of the surface of the material 3 to be processed. In FIG. 1, a portion denoted by reference numeral 25 schematically depicts a portion (plasma ring) where plasma can be confined at high density.
As schematically shown in FIG. 2, the top plate 14 is provided so as to be reversibly moved in the vertical direction when viewed from the casing 13. Thereby, the intensity | strength of the magnetic field formed in the surface side of the to-be-processed material 3 can be adjusted. That is, the strength of the magnetic field can be increased by bringing the top plate (cathode) 14 closer to the casing 13 (that is, the magnets 15 a and 15 b), while the strength of the magnetic field is decreased by moving the top plate 14 away from the casing 13. can do. In the present apparatus 1, a general Z-axis stage mechanism (not shown) is provided, and the distance (D) between the magnets 15a and 15b and the workpiece 3 can be varied within a range of 3 mm to 18 mm.

Next, the power supply part 10 which comprises the plasma generation means in the plasma CVD apparatus 1 which concerns on this embodiment is demonstrated. As shown in FIG. 1, the power supply unit 10 is composed of a high-frequency power supply (RF) 11 that is electrically connected to the cathode (top plate 14) and the anode (container side wall 8) using various elements. A matching circuit 19 and a capacitor 18 are provided for matching the output impedance of the power supply unit 11 (here, 50Ω) with the plasma impedance in the reaction vessel 2. The high frequency power supply (RF) 11 can output power having a frequency of 13.56 MHz. The output value can be set in the range of 10W to 500W.
The power supply unit 10 also includes a self-bias circuit 20 including an inductance 22 and a voltmeter 21 that are electrically connected to the cathode (top plate 14).
As a result of this configuration, high-frequency power having a predetermined value can be supplied between the cathode (top plate 14) and the anode (container side wall 8) (that is, the internal space of the reaction vessel 2). At the same time, it is possible to measure the self-bias voltage when a predetermined value of high-frequency power is supplied. The detailed circuit configuration (used elements) such as the high-frequency power source (RF) 11, the matching circuit 19, and the self-bias circuit 20 constituting the power supply unit may be the same as that of a general plasma CVD apparatus, and particularly characterizes the present invention. Since it is not a thing, detailed description is abbreviate | omitted.

By using the plasma CVD apparatus 1 having the above configuration typically under the following conditions, a hard carbon film can be produced on the surface of a predetermined material to be processed.
That is, first, the material 3 to be processed is disposed on the cathode (top plate) 14. Then, the raw material gas is supplied from the external gas supply source through the gas supply pipe 7 into the reaction vessel 2 under the reduced pressure condition. On the other hand, high frequency power is applied from the high frequency power supply 11 to the cathode 14 with a predetermined output. At the same time, a self-bias voltage is applied to the surface of the workpiece 3 disposed on the cathode 14.
Thus, glow discharge is generated in the space in the reaction vessel 2, thereby generating plasma derived from the source gas. At this time, a magnetic field is locally formed in the vicinity of the surface of the material 3 to be processed by the magnets 15a and 15b, and the plasma generated in the container 2 can be confined with high density. By the way, in the present apparatus 1, the self-bias voltage value changes under the influence of a magnetic field parallel to the material 3 (that is, the cathode 14) as shown by the magnetic field line loop 23 in FIG. Specifically, the self-bias voltage is lower in a portion where the intensity of the parallel magnetic field (magnetic flux density: B _parallel ) is higher. As a result, the plasma impedance is lowered in the portion where the self-bias voltage applied to the surface of the workpiece 3 is low, and the plasma can converge in the portion. As a result, the film forming speed of the strong magnetic field portion on the surface of the material to be processed 3 is accelerated, and a hard carbon film can be obtained at a high film forming speed.
Moreover, the film-forming speed | rate can be adjusted by changing the magnetic flux density (B _parallel ) by changing the distance (D) of the magnets 15a and 15b and the to-be-processed material 3. FIG.

<Test Example 1>
Using this plasma CVD apparatus 1 using a silicon thin substrate (diameter of about 10 cm) as the material 3 to be processed, the distance (D) between the magnets 15a, 15b and the material 3 to be processed is 3 mm, 6 mm, 9 mm, It is changed to 12 mm, 15 mm and 18 mm, and the strength of the magnetic field formed on the surface of the material 3 to be processed at each distance is used as a general magnetic flux with the parallel magnetic field strength (magnetic flux density: B _parallel ) as an index. It measured using the density meter (Tesla meter).
That is, after the material to be treated 3 was placed on the cathode 14, the surface of the material to be treated 3 was scanned with a hole probe of a Teslameter, and the magnetic flux density (B _parallel ) in each part of the material to be treated 3 was measured. The results are shown in FIG. The horizontal axis of FIG. 3 shows the radial distance (mm) from the center position when the center of the disk-shaped top plate (cathode) 14 is zero. The vertical axis | shaft of FIG. 3 shows magnetic flux density (B _parallel : T).
As is clear from the results shown in FIG. 3, the magnitude of the parallel magnetic flux density (B _parallel ) on the surface of the material 3 to be processed is the magnetic field line loop 23 extending from the N pole 15b to the S pole 15a schematically shown in FIG. Tune in. That is, the magnitude of the parallel magnetic flux density (B _parallel : T) changes concentrically, and shows the maximum magnetic flux density in a portion located approximately in the middle between the N pole 15b and the S pole 15a constituting the magnetic circuit. This is because, in the present plasma CVD apparatus 1, the configuration of the magnetic circuit on the back surface side of the material to be processed, specifically, the arrangement of the N pole 15b and the S pole 15a is appropriately changed, so that the parallel magnetic flux density (B _parallel : T) means that the position where T) is maximized can be set to an arbitrary position on the surface side of the workpiece 3 (that is, the surface side of the cathode 14). For example, by appropriately arranging the N pole and the S pole, the central portion of the disk-shaped top plate (cathode) 14 can be a portion showing the maximum value of the parallel magnetic flux density (B _parallel : T).
Further, as is apparent from the results shown in FIG. 3, the magnitude of the magnetic flux density can be appropriately adjusted by changing the distance (D) between the magnets 15a and 15b and the material 3 to be processed. Here, by varying the distance (D) between 3 mm and 18 mm, the maximum value of the parallel magnetic flux density (B _parallel : T) could be adjusted between approximately 0.02 and 0.07 T.

<Test Example 2>
Next, among the conditions shown in Test Example 1 (FIG. 3), a state in which the distance (D) between the magnets 15a and 15b and the material to be processed 3 is set to 3 mm and a magnetic field is formed on the surface of the material 3 to be processed. Thus, a hard carbon film (DLC film) was actually manufactured on the workpiece 3.
That is, after reducing the pressure in the reaction vessel 2 to about 6 × 10 ⁻³ Pa in advance, methane gas was supplied into the vessel 2 as a raw material gas so that the internal pressure of the vessel became 20 Pa. In this state, high-frequency power was applied to the cathode 14 with an output of 400 W or 80 W from the high-frequency power source (frequency 13.56 MHz) 11, and plasma CVD was performed. After a predetermined time, this treatment was terminated, and the properties of the hard carbon film formed on the surface of the material to be treated 3 were examined. As a comparative test, the same plasma CVD (high frequency output: 400 W) was performed with the magnetic circuit (that is, the magnets 15a and 15b) removed. The results are shown in FIG. FIG. 4 shows the film forming speed at each surface portion of the material 3 to be processed. The horizontal axis indicates the radial distance (mm) from the center position where the center of the cathode 14 is zero. The vertical axis represents the deposition rate (deposition rate: nm / min) of the carbon film. In the figure, the circle plot represents the film formation rate at an output of 400 W, the triangle plot represents the film formation rate at an output of 80 W, and the square plot represents the film formation in a comparative test, that is, when no magnetic field is formed (output 400 W). Expresses speed.

As can be seen from FIG. 4, the production method of the present invention made it possible to produce (deposit) a hard carbon film at a significantly higher rate than the comparative test in which no magnetic field was applied. Moreover, it was recognized that the higher the high frequency output, the more the film formation rate can be improved. Specifically, when the applied high frequency power is 400 W, the film formation rate in the comparative test without applying a magnetic field was 47 nm / min, whereas the film formation rate in the test example with a magnetic field applied was 1029 nm at maximum. / Min.
Further, as a general tendency, a higher film formation rate can be realized in a portion where the parallel magnetic flux density (B _parallel : T) is high. The following tests were conducted to confirm this. The applied high frequency power was set to 50 W, and film formation was performed in the same manner as in the above test, and the parallel magnetic flux density (B _parallel : T) was 0.015T, 0.025T, 0.035T, 0.045T, 0.055T, and The film formation rate at a site of 0.065T was measured. The results are shown in FIG. The horizontal axis represents the magnetic flux density, and the vertical axis represents the film formation rate. As is apparent from FIG. 5, it was confirmed that generally the higher the parallel magnetic flux density (B _parallel : T), the higher the deposition rate of the hard carbon film.

<Test Example 3>
Next, the hardness (hardness: GPa) and elastic modulus (GPa) of the obtained hard carbon film were measured. In this test, the high frequency output to be applied was eight types of 50 W, 100 W, 150 W, 200 W, 250 W, 300 W, 350 W, and 400 W.
That is, the distance (D) between the magnets 15a and 15b and the material 3 to be processed was set to 3 mm, and plasma CVD similar to the above test example was performed. The hardness and elastic modulus of the part where the parallel magnetic flux density on the surface of the material to be processed was 0.065T were measured by the nanoindentation method. The results are shown in FIG. The horizontal axis represents the high-frequency output value (W), the left vertical axis represents hardness (GPa), and the right vertical axis represents elastic modulus (GPa). The square plot in the figure represents the hardness, and the triangular plot represents the elastic modulus.
As shown in FIG. 6, the hardness and elastic modulus of the obtained carbon film showed high values regardless of the high frequency power value. In particular, when the power was 50 to 300 W, high hardness and elastic modulus were exhibited. The case where the power value is 150 to 250 W is more preferable, and particularly at 200 W, the hardness was 16.2 GPa and the elastic modulus was 121.6 GPa. On the other hand, when the input high-frequency power value was 400 W, the film formation rate was the fastest, and the thickest hard carbon film per unit time was obtained, but the stress characteristics slightly decreased. This is considered to be due to the increase in sp ² bonds in the carbon film due to the increase in ion collision due to the application of high energy. Therefore, in order to produce a hard carbon film (typically a DLC film) excellent in stress characteristics (hardness and elastic modulus), an input high-frequency power of 50 to 300 W is preferable, and 100 to 250 W is particularly preferable.

<Test Example 4>
The surface of the hard carbon film manufactured with the applied high frequency power of 50 W, 200 W, and 400 W in Test Example 3 was observed with an atomic force microscope, and the root mean square deviation (RMS value), which is an index value indicating the surface roughness, was calculated. . As a result, the RMS value at the location was 8.41 nm for 50 W, 3.34 nm for 200 W, and 1.69 nm for 400 W. From these RMS values, it is understood that the smoothness of the hard carbon film improves as the applied high frequency power increases.
In order to produce a hard carbon film with good smoothness by the method according to the present disclosure, it is preferable to carry out at a higher applied high frequency power. For example, in the example shown here, one carried out at 300 to 400 W is preferred.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
In addition, the technical elements described in the present specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

It is a schematic diagram which shows an example of the plasma CVD apparatus of this invention. It is a schematic diagram which expands and shows the principal part of FIG. It is a graph which shows the relationship between the radial distance of a cathode (to-be-processed material) surface, and a parallel magnetic flux density. It is a graph which shows the relationship between the radial distance of a cathode (to-be-processed material) surface, and the film-forming speed | rate of the hard carbon film in the to-be-processed material surface. It is a graph which shows the relationship between a parallel magnetic flux density and the film-forming speed | rate of the hard carbon film in the to-be-processed material surface. It is a graph which shows the relationship between the applied high frequency electric power in a site | part whose parallel magnetic flux density is 0.065T, hardness, and an elasticity modulus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Plasma CVD apparatus 2 Reaction container 3 Material to be processed (silicon substrate)
5 Arrangement 8 Side Wall (Anode)
DESCRIPTION OF SYMBOLS 10 Power supply part 11 High frequency power supply 14 Cathode 15a, 15b Magnet 23 Magnetic field line loop 25 High-density area | region (plasma ring) of plasma

Claims (5)

A method for producing a hard carbon film on the surface of a material to be treated based on a plasma CVD method, comprising the following steps:
Placing the material to be treated in the reaction vessel;
A step of arranging a magnet on the back surface side of the material to be treated disposed in the reaction vessel and locally forming a magnetic field on the surface side of the material to be treated and its vicinity; and introducing a raw material gas into the reaction vessel And generating plasma in the container;
Including the method.   The method according to claim 1, wherein plasma is generated in the container by supplying high-frequency power to the reaction container, and the material to be treated is disposed on an electrode to which the high-frequency power is applied.   The method of Claim 1 or 2 which arrange | positions the said magnet so that a magnetic force line loop may be formed on the surface of the to-be-processed material arrange | positioned in the said reaction container. A reaction vessel capable of introducing a raw material gas;
Plasma generating means for generating plasma in the container;
An arrangement part for arranging the material to be treated so that a product derived from the raw material gas can be deposited on the surface of the material to be treated in the container;
One or two or more magnets provided on the back side of the material to be processed arranged in the arrangement part, and a magnet that locally forms a magnetic field on the surface side of the material to be processed and in the vicinity thereof;
A plasma CVD apparatus comprising:   The apparatus according to claim 4, wherein the plasma generating unit is configured to supply high-frequency power into the reaction vessel, and the arrangement unit includes an electrode to which high-frequency power is applied.

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