TW201804011A - Plasma CVD apparatus and film formation method capable of enhancing the uniformity of film thickness - Google Patents

Abstract

Disclosed is a plasma CVD apparatus capable of enhancing the uniformity of film thickness. One aspect of the present invention is a plasma CVD apparatus, which includes: a vacuum chamber (1), a holding electrode (2) disposed in the vacuum chamber (1) and holding a deposition target substrate (20), a counter electrode (12) disposed in the vacuum chamber (1) and arranged to face the deposition target substrate (20) held by the holding electrode (2), a first high frequency power supply (8) electrically connected to one of the holding electrode (2) or the counter electrode (12) and with a frequency between 5 kHz or more and 500 kHz or less, a second high frequency power supply (9) electrically connected to the other of the holding electrode (2) or the counter electrode (12) and with a frequency between 1 MHz or more and 27 MHz or less, a source gas supply mechanism (24) supplying source gas into the vacuum chamber (1), and a vacuum evacuation mechanism (23) evacuating air inside the vacuum chamber (1).

Description

Plasma CVD device and film forming method

The present invention relates to a plasma CVD (Chemical Vapor Deposition) device and a film forming method.

A conventional plasma CVD apparatus includes a film formation chamber, an electrode positioned below the film formation chamber and held by a film formation substrate, and a gas shower electrode disposed in parallel to the electrode. These are a pair of parallel flat electrode. The electrode is electrically connected to a high-frequency power source, and the electrode functions as an RF application electrode. The gas shower electrode is connected to a ground potential.

The gas shower electrode has a mechanism for introducing a shower-shaped raw material gas into the film forming chamber. In addition, the plasma CVD apparatus has an exhaust port for evacuating the inside of the film forming chamber, and the exhaust port is connected to an exhaust pump (for example, refer to Patent Document 1).

In the foregoing plasma CVD apparatus, when a plasma CVD method is used to form a film on a substrate to be formed, a single high-frequency frequency is applied from a high-frequency power source to an electrode, and the film formed on the substrate to be formed may be A film thickness distribution is produced. This film thickness distribution becomes larger as the substrate to be formed becomes larger (that is, as the film formation area becomes larger), and the uniformity of the film thickness becomes lower.

[Prior technical literature] [Patent Literature]

[Patent Document 1] JP 2010-13676 (Figure 2)

One aspect of the present invention is to provide a plasma CVD apparatus or a film forming method capable of improving film thickness uniformity.

Hereinafter, various aspects of the present invention will be described.

[1] A plasma CVD apparatus comprising: a vacuum chamber; a holding electrode disposed in the vacuum chamber to hold a substrate to be formed; and a plasma electrode CVD apparatus disposed in the vacuum chamber to face the substrate held by the holding electrode. A counter electrode arranged on a film substrate; a first high-frequency power source having a frequency of 5 kHz to 500 kHz electrically connected to one of the holding electrode or the counter electrode; and the other of the holding electrode or the counter electrode A second high-frequency power source having an electrical frequency of 1 MHz to 27 MHz; a source gas supply mechanism for supplying a source gas into the vacuum chamber; and a vacuum exhaust mechanism for evacuating the vacuum chamber.

[2] The plasma CVD apparatus according to the above [1], wherein a high-frequency output from one of the holding electrode or the counter electrode applied by the first high-frequency power source is a watt / cm ² , and When the high-frequency output from the other of the holding electrode or the counter electrode applied by the second high-frequency power source is b watt / cm ² , the following formula 1 is satisfied.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

[3] A plasma CVD apparatus comprising: a vacuum chamber; a holding electrode disposed in the vacuum chamber to hold a substrate to be formed; and a plasma electrode CVD apparatus disposed in the vacuum chamber to face the substrate being held by the holding electrode. A counter electrode arranged on a film substrate; a first high-frequency power source having a frequency of 5 kHz to 500 kHz and a second high-frequency power source having a frequency of 1 MHz to 27 MHz which are electrically connected to one of the holding electrode or the counter electrode; A ground wire electrically connected to the other of the holding electrode or the counter electrode; a source gas supply mechanism for supplying a source gas into the vacuum chamber; and a vacuum exhaust mechanism for evacuating the vacuum chamber.

[4] The plasma CVD apparatus according to the above [3], wherein the high-frequency output from one of the holding electrode or the counter electrode applied by the first high-frequency power source is a watt / cm ² , and When the high-frequency output from one of the holding electrode or the counter electrode applied by the second high-frequency power source is b watt / cm ² , the following formula 1 is satisfied.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

[5] The plasma CVD apparatus according to any one of the above [1] to [4], wherein the source gas contains at least one of carbon and silicon.

[6] The plasma CVD apparatus according to the above [5], wherein the source gas containing the silicon includes a silicon compound containing two or more Si atoms.

[7] The plasma CVD apparatus according to any one of the above [1] to [5], wherein the aforementioned raw material gas includes: chain hydrocarbon or cyclic silicon carbide.

[8] The plasma CVD apparatus according to the above [7], wherein the chain hydrocarbon includes: at least one selected from the group of methane, ethane, acetylene, propane, and butane; and the ring silicon carbide includes : At least one of benzene and toluene.

[9] The plasma CVD apparatus according to any one of the above [1] to [8], wherein the outer diameter of the film-formed substrate is 200 mm or more.

[10] A film formation method, which uses a plasma CVD device to form a carbon film or a Si-based film on a substrate to be formed; the plasma CVD device includes: a vacuum chamber; and is disposed in the vacuum chamber to maintain the film to be formed A holding electrode of a substrate; a counter electrode disposed in the vacuum chamber and opposed to the film-formed substrate held by the holding electrode; wherein the film forming method: vacuum exhaust the vacuum chamber; A source gas containing at least one of carbon and silicon is supplied to the vacuum chamber; a high-frequency power of 5 kHz to 500 kHz is applied to one of the holding electrode or the counter electrode; and the holding electrode or the pair High-frequency power having a frequency of 1 MHz to 27 MHz is applied to the other electrode.

[11] The film forming method according to the above [10], wherein high-frequency power from the one of the holding electrode or the counter electrode when the high-frequency power is applied to one of the holding electrode or the counter electrode is applied. The output is a watt / cm ² , and the high-frequency output from the other of the holding electrode or the counter electrode when the high-frequency power is applied to the other of the holding electrode or the counter electrode is b watt / When cm ² , the following formula 1 is satisfied.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

[12] A film formation method, which uses a plasma CVD device to form a carbon film or a Si-based film on a substrate to be formed; the plasma CVD device includes: a vacuum chamber; and is disposed in the vacuum chamber to maintain the film to be formed A holding electrode of a substrate; a counter electrode arranged in the vacuum chamber and facing the film-formed substrate held by the holding electrode; wherein the film forming method: vacuum exhaust the vacuum chamber; In the vacuum chamber, a source gas containing at least one of carbon and silicon is supplied; While applying high-frequency power at a frequency of 5 kHz to 500 kHz to one of the holding electrode or the counter electrode, high-frequency power at a frequency of 1 MHz to 27 MHz is applied; One applies a ground potential.

[13] The film forming method according to the above [12], wherein when the high-frequency power of 5 kHz to 500 kHz is applied to one of the holding electrode or the counter electrode, the film from the holding electrode or the counter electrode is applied. The high-frequency output of one is a watt / cm ² , and one of the holding electrode or the counter electrode will be from the holding electrode or the counter electrode when high-frequency power of 1 MHz to 27 MHz is applied to one of the holding electrode or the counter electrode. When the high-frequency output is b watts / cm ² , the following formula 1 is satisfied.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

[14] The film formation method according to any one of [10] to [13], wherein the pressure in the vacuum chamber when a carbon film or a Si-based film is formed on the film-formed substrate is 1 Pa or more and 20 Pa or less. .

According to one aspect of the present invention, it is possible to provide a plasma CVD apparatus or a film forming method capable of improving uniformity of film thickness.

1‧‧‧vacuum chamber

2‧‧‧ holding electrode

6‧‧‧ 1st matching block (M.B.)

7‧‧‧ 2nd matching block (M.B.)

8‧‧‧1st high frequency power supply

9‧‧‧ 2nd high frequency power supply

12‧‧‧ counter electrode

21, 22‧‧‧ insulator

23‧‧‧Vacuum exhaust mechanism

24‧‧‧Material gas supply mechanism

1 is a cross-sectional view schematically showing a plasma CVD apparatus according to an aspect of the present invention.

[Fig. 2] A diagram schematically showing a plasma density generated by a plasma CVD apparatus shown in Fig. 1. [Fig.

3 is a cross-sectional view schematically showing a plasma CVD apparatus according to an aspect of the present invention.

[Fig. 4] (A) is a diagram schematically showing a plasma density generated when a high-frequency power of 13.56 MHz is applied, and (B) is a diagram schematically showing a plasma density generated when a high-frequency power of 380 kHz is applied Illustration.

Fig. 5 is a plan view showing a Si substrate of an example.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and those skilled in the art can easily understand and change the form without departing from the spirit and scope of the present invention. The present invention is not limited to the description and examples of the embodiments described below.

[First Embodiment]

FIG. 1 is a cross-sectional view schematically showing a plasma CVD apparatus according to an aspect of the present invention. This plasma CVD apparatus includes a vacuum chamber 1 in which a holding electrode 2 that holds a film-forming substrate 20 is disposed. The holding electrode 2 is insulated from the vacuum chamber 1 by an insulator 21. The holding electrode 2 is electrically connected to a frequency of 5 kHz or more through the first matching block (M.B.) 6 The first high-frequency power supply 8 of 500 kHz or less (preferably 100 kHz or more and 400 kHz or less). The first high-frequency power source 8 is electrically connected to a ground line.

In the vacuum chamber 1, a counter electrode 12 is arranged to face the film formation substrate 20 held by the holding electrode 2. The counter electrode 12 is insulated from the vacuum chamber 1 by an insulator 22. The counter electrode 12 is electrically connected to a second high-frequency power source 9 having a frequency of 1 MHz to 27 MHz (preferably 6 MHz to 13.56 MHz) through a second matching block (M.B.) 7. The second high-frequency power source 9 is electrically connected to a ground line. In addition, the vacuum chamber 1 is electrically connected to a ground line.

The plasma CVD apparatus may include a control unit to control the first high-frequency power supply 8 and the second high-frequency power supply 9 to output simultaneously. This control unit supplies high-frequency power of 5 kHz to 500 kHz from the first high-frequency power supply 8 to the film formation substrate 20 through the holding electrode 2 and supplies high-frequency power of 1 MHz to 27 MHz from the second high-frequency power supply 9. Power to the counter electrode 12.

The planar shape of each of the holding electrode 2 and the counter electrode 12 may be a rectangular shape or a circular shape, but it may be the same as the planar shape of the substrate 20 to be formed. That is, when the planar shape of the film-formed substrate 20 is rectangular, the planar shape of each of the holding electrode 2 and the counter electrode 12 may be rectangular, and when the planar shape of the film-formed substrate 20 is circular, the holding electrode 2 and the counter electrode The planar shape of each of the electrodes 12 may be circular. The outer diameter of the film formation substrate 20 may be 200 mm or more. In addition, the "outer diameter of the substrate to be formed" in this specification, when the planar shape of the substrate to be formed is rectangular, refers to the longer side length, and the planar shape of the substrate to be formed is When round or round, it refers to the longest outer diameter.

In addition, the plasma CVD apparatus includes a vacuum evacuation mechanism 23 for evacuating the inside of the vacuum chamber 1. The vacuum exhaust mechanism 23 is, for example, a vacuum pump. In addition, the plasma CVD apparatus includes a source gas supply mechanism 24 that supplies a source gas into the vacuum chamber 1. Specifically, the source gas supply mechanism 24 is a mechanism that supplies a source gas in a space between the counter electrode 12 and the holding electrode 2. The counter electrode 12 is a gas shower electrode that introduces the source gas into the vacuum chamber 1 in a shower shape.

The source gas may contain at least one of carbon and silicon. Thereby, a carbon film or a Si-based film can be formed. The Si-based film is, for example, a silicon carbide (SiC _x ) film, a silicon oxide (SiO _x ) film, a silicon nitride (SiN _x ) film, or the like. The silicon-containing source gas may include a silicon compound containing two or more Si atoms, such as HMDSN (C ₆ H ₁₉ NSi ₂ ).

In addition, the source gas may include: chain hydrocarbon or cyclic silicon carbide. The chain hydrocarbon may include at least one selected from the group of methane, ethane, acetylene, propane, and butane. The cyclic silicon carbide may include at least one of benzene and toluene.

Next, a film forming method for forming a carbon film or a Si-based film on a substrate to be formed using the plasma CVD apparatus of FIG.

First, the film formation substrate 20 is held on the holding electrode 2. As the film formation substrate 20, for example, a Si substrate, a plastic substrate, a glass substrate, or the like can be used. Next, the inside of the vacuum chamber 1 is evacuated by the vacuum evacuation mechanism 23. Next, the source gas is supplied from the source gas supply mechanism 24 into the counter electrode 12 which is a gas shower electrode, and from the counter electrode The inside of 12 introduces the source gas into the space on the holding electrode 2 in a shower shape. The balance between the supply amount of the raw material gas and the exhaust gas is set as a desired condition such as a predetermined pressure and a predetermined flow rate of the raw material gas. The source gas may be the one described above. The predetermined pressure is preferably 1 Pa or more and 20 Pa or less.

Then, the first high-frequency power source 8 applies high-frequency power of 5 kHz to 500 kHz to the holding electrode 2, and the second high-frequency power source 9 applies high-frequency power of 1 MHz to 27 MHz to the counter electrode 12. . Thereby, a plasma is formed on the surface of the film-forming substrate 20 by the discharge between the film-forming substrate 20 and the counter electrode 12, and a carbon film or Si is formed on the film-forming substrate 20 by a plasma CVD method. Mesangium. Thereafter, the film formation substrate 20 is taken out of the vacuum chamber 1.

FIG. 2 is a diagram schematically showing a plasma density generated by the plasma CVD apparatus shown in FIG. 1. FIG. After the plasma is generated on the surface of the substrate 20 to be formed in the manner described above, as shown in FIG. 2, the high-frequency power of 380 kHz in the range of 5 kHz to 500 kHz is applied to the holding electrode. As a result, high-density plasma is generated from the center to the periphery of the electrode. On the other hand, high-frequency power of 13.56 MHz in the range of 1 MHz to 27 MHz is applied to the counter electrode, and high-density plasma is generated from the periphery of the counter electrode to the center. In other words, a concave plasma is generated on a holding electrode to which a low-frequency high-frequency power of 5 kHz to 500 kHz is applied, and a counter-electrode to which a high-frequency power of 1 MHz to 27 MHz is applied generates a convex-shaped plasma. Pulp. Therefore, the plasma generated on the holding electrode and the plasma generated on the counter electrode are synthesized and then held. The difference in plasma density between the center and the outer periphery of the film-forming substrate on the holding electrode can be reduced, and the uniformity of the plasma density on the surface of the film-forming substrate can be improved.

According to this embodiment, the application of high-frequency power with a low frequency to the holding electrode 2 and the application of high-frequency power with a high frequency to the counter electrode 12 can improve the uniformity of the plasma density on the surface of the substrate 20 to be formed. As a result, the uniformity of the film thickness of the carbon film or the Si-based film formed on the film formation substrate 20 can be improved. In addition, the film thickness distribution can be improved.

The high-frequency output from the holding electrode 2 when high-frequency power is applied to the holding electrode 2 by the first high-frequency power supply 8 is referred to as a watt / cm ² , and the counter electrode 12 is opposed to the second high-frequency power supply 9. When the high-frequency output from the counter electrode 12 when high-frequency power is applied is b watt / cm ² , it is preferable to satisfy the following formula 1. Thereby, the uniformity of the plasma density on the surface of the film-formed substrate 20 can be further improved, and as a result, the uniformity of the thickness of the carbon film or the Si-based film formed on the film-formed substrate 20 can be improved.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

In this embodiment, the first high-frequency power source 8 applies a high-frequency power of 5 kHz to 500 kHz to the holding electrode 2, and the second high-frequency power source 9 applies a frequency of 1 MHz or more to the counter electrode 12. High-frequency power below 27 MHz, but the first high-frequency power source 8 applies high-frequency power at a frequency of 5 kHz to 500 kHz to the counter electrode 12, and the second high-frequency power source 9 applies a frequency of 1 MHz or more to the holding electrode 2. High-frequency power below 27MHz is also available.

[Second Embodiment]

FIG. 3 is a cross-sectional view schematically showing a plasma CVD apparatus according to an aspect of the present invention. The same parts as those in FIG. 1 are assigned the same reference numerals, and only different points are described here.

In the plasma CVD apparatus shown in FIG. 1, a second high-frequency power source 9 having a frequency of 1 MHz to 27 MHz is electrically connected to the counter electrode 12 through a second matching block 7. However, the plasma CVD shown in FIG. 3 In the device, the second high-frequency power source 9 having a frequency of 1 MHz to 27 MHz is electrically connected to the holding electrode 2 through the second matching block 7, and the counter electrode 12 is connected to a ground line, which is different.

In other words, in the plasma CVD apparatus shown in FIG. 3, high-frequency power of 5 kHz to 500 kHz (preferably 100 kHz to 400 kHz) is applied to the holding electrode 2 by the first high-frequency power source 8. At the same time, the second high-frequency power source 9 applies high-frequency power having a frequency of 1 MHz to 27 MHz (preferably 6 MHz to 13.56 MHz), and the counter electrode 12 is grounded. Thereby, a plasma is formed on the surface of the film-forming substrate 20 by the discharge between the film-forming substrate 20 and the counter electrode 12, and a carbon film or Si is formed on the film-forming substrate 20 by a plasma CVD method. Mesangium.

FIG. 4 (A) is a diagram schematically showing a plasma density generated when high-frequency power of 13.56 MHz is applied to a holding electrode of the plasma CVD apparatus shown in FIG. 3 in a range of 1 MHz to 27 MHz. FIG. 4 (B) is a diagram schematically showing a plasma density generated when high-frequency power of 380 kHz in a range of 5 kHz to 500 kHz is applied to the holding electrodes of the plasma CVD apparatus shown in FIG. 3.

As shown in FIG. 4 (A), when high-frequency power of 13.56 MHz is applied to the holding electrode, a high-density plasma is generated from the outer periphery to the center of the surface of the substrate to be formed. That is, the holding electrode to which high-frequency power of 13.56 MHz is applied generates a convex plasma. On the other hand, as shown in FIG. 4 (B), when high-frequency power of 380 kHz is applied to the holding electrode, a high-density plasma is generated from the center to the outer periphery of the surface of the substrate to be formed. That is, the holding electrode to which the high-frequency power of 380 kHz is applied generates a concave plasma.

According to this embodiment, as shown in FIG. 3, since high-frequency power of 5 kHz to 500 kHz is applied to the holding electrode 2, high-frequency power of 1 MHz to 27 MHz is also applied. The plasma shown in FIG. 4 (A) and The plasma shown in FIG. 4 (B) is synthesized, and the plasma density difference between the center and the periphery of the film-forming substrate 20 held on the holding electrode 2 can be reduced, and the plasma density on the surface of the film-forming substrate can be increased. Uniformity. As a result, the uniformity of the film thickness of the carbon film or the Si-based film formed on the film formation substrate 20 can be improved. In addition, the film thickness distribution can be improved.

The high-frequency output from the holding electrode 2 when the high-frequency power is applied to the holding electrode 2 by the first high-frequency power supply 8 is referred to as a watt / cm ² , and the holding electrode 2 is applied by the second high-frequency power supply 9. When the high-frequency output from the holding electrode 2 during high-frequency power is b watts / cm ² , it is preferable to satisfy the following formula 1. Thereby, the uniformity of the plasma density on the surface of the film formation substrate 20 can be further improved, and as a result, the uniformity of the film thickness of the carbon film or the Si-based film formed on the film formation substrate 20 can be improved.

0.01a <b <0.5a (preferably 0.05a ≦ b ≦ 0.2a) ‧ ‧ formula 1

In this embodiment, the first high-frequency power source 8 applies high-frequency power at a frequency of 5 kHz to 500 kHz to the holding electrode 2 and the second high-frequency power source 9 applies a frequency to the counter electrode 2 at The high-frequency power between 1 MHz and 27 MHz is grounded to the counter electrode 12. However, the first high-frequency power source 8 applies high-frequency power at a frequency of 5 kHz to 500 kHz to the counter electrode 12 and a second high-frequency power. The power source 9 may apply high-frequency power having a frequency of 1 MHz to 27 MHz to the counter electrode 12 and may ground the holding electrode 2.

The first embodiment and the second embodiment may be appropriately combined and implemented.

[Example]

Table 1 shows the film thickness distribution when a DLC film is formed using the plasma shown in FIG. 4 (A), and the film thickness distribution when the DLC film is formed using a plasma shown in FIG. 4 (B). Hereinafter, it will be described in more detail.

In the plasma CVD apparatus shown in FIG. 3, since high-frequency power is not applied to the holding electrode 2 from the first high-frequency power source 8, high-frequency power of 13.56 MHz is applied to the holding electrode 2 by the second high-frequency power source 9. And the counter electrode 12 is grounded to form a plasma as shown in FIG. 4 (A) to form a DLC membrane. The film formation conditions at this time are as follows.

(Film forming conditions)

Film-forming device: Plasma CVD device shown in Figure 3

Film formation substrate 20: Si substrate (20mm × 20mm) shown in FIG. 5

Substrate temperature: room temperature

Holding electrode 2: substrate holder electrode

Counter electrode 12: gas shower electrode

Distance between holding electrode 2 and counter electrode 12: 80mm

Power frequency: 13.56MHz

Power output: 0.82W / cm ²

Raw material gas: toluene

Toluene flow: 30sccm

Toluene gas pressure: 3Pa

The results of measuring the film thickness of the DLC film formed under the above-described film forming conditions at the measurement positions 1 to 5 (center and end) shown in FIG. 5 are shown in the upper stage of Table 1.

Next, in the plasma CVD apparatus shown in FIG. 3, since the high-frequency power is not applied to the holding electrode 2 from the second high-frequency power source 9, high-frequency power at 380 kHz is applied to the holding electrode by the first high-frequency power source 8. 2 and the counter electrode 12 is grounded to generate a plasma as shown in FIG. 4 (B) to form a DLC film. The film formation conditions at this time are as follows.

(Film forming conditions)

Film-forming device: Plasma CVD device shown in Figure 3

Film formation substrate 20: Si substrate (20mm × 20mm) shown in FIG. 5

Substrate temperature: room temperature

Holding electrode 2: substrate holder electrode

Counter electrode 12: gas shower electrode

Distance between holding electrode 2 and counter electrode 12: 80mm

Power frequency: 380kHz

Power output: 0.82W / cm ²

Raw material gas: toluene

Toluene flow: 30sccm

Toluene gas pressure: 3Pa

The results of measuring the film thickness of the DLC film formed under the above-mentioned film formation conditions at the measurement positions 1 to 5 (center and end) shown in FIG. 5 are shown in the lower stage of Table 1.

According to Table 1, it was confirmed that the DLC film had a convex film thickness distribution when the power frequency was 13.56 MHz, and the DLC film had a concave film thickness distribution when the power frequency was 380 kHz.

Table 2 shows the film thickness distribution when a DLC film is formed by the plasma CVD apparatus shown in FIG. 1. This will be described in detail below.

(Film forming conditions)

Film-forming device: Plasma CVD device shown in Figure 1

Film formation substrate 20: Si substrate (20mm × 20mm) shown in FIG. 5

Substrate temperature: room temperature

Holding electrode 2: substrate holder electrode

Counter electrode 12: gas shower electrode

Distance between holding electrode 2 and counter electrode 12: 80mm

Frequency of the first high-frequency power supply 8: 380 kHz

Output of the first high-frequency power supply 8: 0.82 W / cm ²

Frequency of the second high-frequency power source 9: 13.56 MHz

Output of the second high-frequency power source 9: 0.04 ~ 0.24W / cm ²

Raw material gas: toluene

Toluene flow: 30sccm

Toluene gas pressure: 3Pa

Table 2 shows the results of measuring the film thickness of the DLC film formed under the above-described film formation conditions at the measurement positions 1 to 5 (center and end) shown in FIG. 5.

The sample 1 (previous method) shown in Table 2 shows the film thickness distribution of the DLC film formed under the same conditions as those described above, except for the point where the gas shower electrode (counter electrode 12) is connected to the ground wire. .

In addition, for samples 2 to 6 shown in Table 2, the output to the gas shower electrode was set to 0.04W / cm ² , 0.06W / cm ² , 0.08W / cm ² , 0.16W / cm ² , and 0.24W, respectively. Other than the point of / cm ² , the film thickness distribution of the DLC film formed under the same conditions as the above-mentioned film forming conditions is shown.

In addition, the film thickness distribution shown in Table 2 is that the thickest film thickness among the film thicknesses measured at the measurement positions 1 to 5 shown in FIG. 5 is set to MAX, and when the thinnest film thickness is set to MIN, the following formula is used 2 Calculators.

(MAX-MIN) / (MAX + MIN) × 100 (%) ‧‧‧Formula 2

In addition, n (refractive index) shown in Table 2 was measured by the following method. The film thickness was measured using F20, an optical film thickness meter, manufactured by Filmetrics, INC. The refractive index was calculated using reflectance spectrometry and Cauchy model.

According to Table 2, the high-frequency output (0.04 ~ 0.16W) of 5 to 20% of the high-frequency output of 0.82W / cm ² from the first high-frequency power supply 8 to the substrate holder electrode (holding electrode 2) is obtained. / cm ² ) Output from the second high-frequency power source 9 to the gas shower electrode (counter electrode 12), and it was confirmed that the film thickness uniformity of the DLC film formed on the film formation substrate 20 can be improved.

1‧‧‧vacuum chamber

2‧‧‧ holding electrode

6‧‧‧ 1st matching block (M.B.)

7‧‧‧ 2nd matching block (M.B.)

8‧‧‧1st high frequency power supply

9‧‧‧ 2nd high frequency power supply

12‧‧‧ counter electrode

20‧‧‧ film-formed substrate

21, 22‧‧‧ insulator

23‧‧‧Vacuum exhaust mechanism

24‧‧‧Material gas supply mechanism

Claims (14)

A plasma CVD apparatus includes: a vacuum chamber; a holding electrode disposed in the vacuum chamber and holding a film-forming substrate; and a plasma electrode CVD device disposed in the vacuum chamber and facing the film-forming substrate held by the holding electrode. A counter electrode arranged; a first high-frequency power source with a frequency of 5 kHz to 500 kHz that is electrically connected to the holding electrode or one of the counter electrodes; and that is electrically connected to the holding electrode or the other of the counter electrode A second high-frequency power source having a frequency of 1 MHz to 27 MHz; a source gas supply mechanism for supplying a source gas into the vacuum chamber; and a vacuum exhaust mechanism for evacuating the vacuum chamber. The plasma CVD apparatus according to claim 1, wherein the high-frequency output from one of the holding electrode or the counter electrode applied by the first high-frequency power source is a watt / cm ² , and the second high-frequency power is When the high-frequency output from the other of the holding electrode or the counter electrode applied by the high-frequency power source is b watt / cm ² , the following formula 1: 0.01a <b <0.5a‧‧‧ formula 1 is satisfied. A plasma CVD apparatus includes: a vacuum chamber; and a holding electrode which is disposed in the vacuum chamber and holds a substrate to be formed. A counter electrode disposed in the vacuum chamber and opposed to the film-formed substrate held by the holding electrode; a frequency electrically connected to one of the holding electrode or the counter electrode is 5 kHz to 500 kHz The following first high-frequency power supply and second high-frequency power supply having a frequency of 1 MHz to 27 MHz; a ground wire electrically connected to the other of the holding electrode or the counter electrode; and a raw material for supplying a raw gas into the vacuum chamber A gas supply mechanism; a vacuum exhaust mechanism for vacuum exhausting the vacuum chamber. The plasma CVD apparatus according to claim 3, wherein the high-frequency output from one of the holding electrode or the counter electrode applied by the first high-frequency power source is a watt / cm ² , and the second high-frequency power is When the high-frequency output from one of the holding electrode or the counter electrode applied by the high-frequency power source is b watt / cm ² , the following formula 1: 0.01a <b <0.5a‧‧‧ formula 1 is satisfied. The plasma CVD apparatus according to any one of claims 1 to 4, wherein the source gas contains at least one of carbon and silicon. The plasma CVD apparatus according to claim 5, wherein the source gas containing the silicon includes: containing two or more Si atoms Silicon compounds. The plasma CVD apparatus according to any one of claims 1 to 5, wherein the source gas includes: chain hydrocarbon or cyclic silicon carbide. The plasma CVD apparatus according to claim 7, wherein the chain hydrocarbon includes: at least one selected from the group of methane, ethane, acetylene, propane, and butane; and the cyclic silicon carbide includes: benzene and toluene At least one of them. The plasma CVD apparatus according to any one of claims 1 to 8, wherein the outer diameter of the film-formed substrate is 200 mm or more. A film forming method is to form a carbon film or a Si film on a substrate to be formed by using a plasma CVD device. The plasma CVD device has a vacuum chamber and is arranged in the vacuum chamber to hold a substrate to be formed. An electrode; a counter electrode arranged in the vacuum chamber and opposed to the film-formed substrate held by the holding electrode; wherein the film forming method: vacuum exhausts the vacuum chamber; and evacuates the vacuum chamber In the room, a source gas containing at least one of carbon and silicon is supplied; the frequency applied to one of the holding electrode or the counter electrode is High-frequency power from 5 kHz to 500 kHz; high-frequency power from 1 MHz to 27 MHz is applied to the other of the holding electrode or the counter electrode. The film forming method according to claim 10, wherein a high-frequency output from one of the holding electrode or the counter electrode when the high-frequency power is applied to one of the holding electrode or the counter electrode is a watt. / cm ² , when the high-frequency output from the other of the holding electrode or the counter electrode when the high-frequency power is applied to the other of the holding electrode or the counter electrode is b watt / cm ² , The following formula 1 is satisfied: 0.01a <b <0.5a‧‧‧ Formula 1. A film forming method is to form a carbon film or a Si film on a substrate to be formed by using a plasma CVD device. The plasma CVD device has a vacuum chamber and is arranged in the vacuum chamber to hold a substrate to be formed. An electrode; a counter electrode arranged in the vacuum chamber and opposed to the film-formed substrate held by the holding electrode; wherein the film forming method: vacuum exhausts the vacuum chamber; and evacuates the vacuum chamber In the room, a source gas containing at least one of carbon and silicon is supplied; a frequency applied to one of the holding electrode or the counter electrode is At the same time as high-frequency power from 5 kHz to 500 kHz, high-frequency power from 1 MHz to 27 MHz is applied; a ground potential is applied to the other of the holding electrode or the counter electrode. The film forming method according to claim 12, wherein the high-frequency power from the one of the holding electrode or the counter electrode when the high-frequency power of 5 kHz to 500 kHz is applied to one of the holding electrode or the counter electrode is higher. The frequency output is a watt / cm ² , which is a high-frequency output from the holding electrode or the counter electrode when the high-frequency power of 1 MHz to 27 MHz is applied to one of the holding electrode or the counter electrode. When b watts / cm ² , the following formula 1: 0.01a <b <0.5a‧‧‧ formula 1 is satisfied. The film forming method according to any one of claims 10 to 13, wherein the pressure in the vacuum chamber when a carbon film or a Si-based film is formed on the film-formed substrate is 1 Pa or more and 20 Pa or less.