JP2011228329A - Manufacturing method for gas supply electrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method for a gas supply electrode capable of preventing a through-hole from clogging, roughening a gas supply electrode surface, preventing a positional shift of the through-hole and a breakage of a drill while processing the through-hole to suppress film-forming substance deposited on an electrode surface from adhering to a substrate after being pelt off from the electrode, supplying gas stably, and forming a high quality film.SOLUTION: The manufacturing method includes a hole-processing process to form the plurality of the through-holes by performing hole-processing and a spray process to form a sprayed film by performing a plasma spray treatment against a supply surface on the side facing to the plasma generation region after the hole-processing process.

Description

  The present invention relates to a method for manufacturing a gas supply electrode used in a plasma CVD apparatus.

Various functional films such as gas barrier films, protective films, optical films such as optical filters and antireflection films, etc. in various devices such as optical elements, display devices such as liquid crystal displays and organic EL displays, semiconductor devices, thin film solar cells, etc. (Functional sheet) is used.
In addition, film formation (thin film formation) by a vacuum film formation method such as sputtering or plasma CVD is used for manufacturing these functional films.

  When film formation is performed by plasma CVD, a film is deposited not only on the substrate that is the film formation target but also on each part in the film formation apparatus. In particular, a large amount of a film deposit is deposited on the surface of the electrode opposite to the substrate of the electrode pair for forming a film for forming plasma. The film deposited on the electrode for film formation partially peels off from the electrode and adheres to the substrate or the film formed, and there is a possibility that a high-quality film cannot be formed.

Therefore, in order to prevent the film deposited on the electrode surface from peeling from the electrode, the surface of the electrode is roughened to improve the adhesion between the electrode surface and the deposited film deposited. Yes.
For example, Patent Document 1 includes a first electrode and a second electrode arranged to face each other for generating plasma inside a processing chamber, and includes a first electrode for suppressing peeling of a deposited film. A plasma CVD apparatus is described in which the surface of the electrode on the second electrode side is roughened over the entire surface. This Patent Document 1 also describes that the surface is roughened by performing a blasting process for spraying particles.

JP 2006-173343 A

  Here, as an electrode for plasma CVD, in addition to the function as an electrode, a gas is used to uniformly supply a film-forming gas between the electrodes for forming plasma during film formation. An electrode (shower electrode) having a plurality of through holes for supply is used. Such an electrode is configured by combining a plate-like gas supply electrode (shower plate) having a plurality of through holes and a housing whose one surface is open. During film formation, the gas supplied into the electrode housing is supplied between the electrodes from the through hole of the gas supply electrode.

  However, after forming a plurality of through holes for supplying a gas and performing a blasting process to roughen the surface of the gas supply electrode, particles used in the blasting process are clogged in the through holes. There is a risk of it. When a film is formed using a gas supply electrode with a clogged through hole, the gas flow rate and pressure become unstable, and a high-quality film cannot be formed, or plasma can be generated properly. This causes a problem that the film cannot be formed.

  As a roughening method, a sprayed film is also formed by arc spraying. By forming the sprayed film, the surface roughness can be increased and the film can be more suitably prevented from peeling than the roughening by blasting. However, in the arc spraying, the diameter of the sprayed particles when spraying the spray material is large, and there is a possibility that the through holes are clogged.

In addition, when forming a through hole after roughening the surface of the gas supply electrode, if the hole is drilled from the roughened surface, the position of the hole may be shifted due to surface irregularities, The drill may be eccentric and the drill may be damaged.
Moreover, when forming a through-hole after forming a thermal spray film and roughening, there exists a possibility that a thermal spray film may crack at the interface of a thermal spray film and a base material. If the sprayed film is cracked and the smooth surface of the base material is exposed, peeling of the deposited film cannot be suppressed during film formation.

  The object of the present invention is to eliminate the problems of the prior art, and to roughen the surface of the gas supply electrode without clogging the through hole. Further, when processing the through hole, As a result, the film deposited on the surface of the electrode peels off from the electrode and adheres to the substrate when the film is formed in the plasma CVD apparatus. It is an object of the present invention to provide a method of manufacturing a gas supply electrode that can suppress the above-described problem, can stably supply a gas, and can form a high-quality film on a substrate.

  In order to solve the above-mentioned problems, the present invention is a method for manufacturing a gas supply electrode having a plurality of through holes used in a plasma CVD apparatus, wherein the holes are drilled to form the plurality of through holes. And a spraying step of forming a sprayed film by plasma spraying on the supply surface facing the plasma generation region after the hole drilling step, and a gas supply electrode manufacturing method comprising: It is to provide.

Here, it is preferable that after the thermal spraying process, there is a film forming process for forming an oxide film on at least the supply surface and the surface of the through hole.
Moreover, it is preferable that the said film formation process performs a plasma oxidation process and forms an oxide film.

Moreover, it is preferable that the said sprayed film is a metal sprayed film which consists of aluminum, aluminum alloy, titanium, magnesium, or stainless steel.
Alternatively, the sprayed film is preferably an alumina ceramic sprayed film.
In addition, the center line average roughness of the supply surface is preferably 5 μm or more.
Furthermore, the center line average roughness of the supply surface is preferably 10 to 30 μm.

The base material of the gas supply electrode is preferably made of any of aluminum, aluminum alloy, magnesium, and titanium.
Moreover, it is preferable that the hole diameter of the said through-hole is 0.7 mm or less.

The plasma CVD apparatus preferably forms a film on the substrate by plasma CVD while conveying a long substrate in the longitudinal direction.
Further, it is preferable that the plasma CVD apparatus performs film formation while the substrate is wound around a predetermined area of a circumferential surface of a cylindrical drum and conveyed.

  According to the present invention, after the hole forming step of forming a plurality of through holes by drilling, a sprayed film is formed by plasma spraying on the supply surface facing the plasma generation region. Without clogging the through hole, it can be roughened, and the position of the hole is not shifted or the drill is not damaged, so when performing film formation in the plasma CVD apparatus, A gas supply electrode that can suppress the film deposited on the surface from being peeled off from the electrode and adhering to the substrate, can perform stable gas supply, and can form a high-quality film on the substrate. Can be manufactured.

It is a figure which shows notionally an example of the film-forming apparatus using the gas supply electrode manufactured with the manufacturing method of this invention. (A) is sectional drawing which shows the gas supply electrode shown in FIG. 1, (B) is the elements on larger scale of (A). It is a flowchart which shows one Example of the manufacturing method of this invention. (A)-(D) are the partial expanded sectional views for demonstrating the manufacturing method of the gas supply electrode shown in FIG. 2, respectively.

  Hereinafter, the manufacturing method of the gas supply electrode of this invention is demonstrated in detail using attached drawing.

In FIG. 1, an example of the film-forming apparatus using the gas supply electrode manufactured by the manufacturing method of this invention is shown notionally. In FIG. 1, a part of the shower electrode 20 is shown in cross section.
The film forming apparatus 10 shown in FIG. 1 is a known roll-to-roll film forming apparatus by CCP-CVD except for the shower plate 22 manufactured by the manufacturing method of the present invention shown in FIG.

The film forming apparatus 10 in the illustrated example forms a film (manufacturing a target function) by plasma CVD on the surface of the substrate Z while conveying a long substrate Z (film original) in the longitudinal direction. / Form) to produce a functional film.
Also, the film forming apparatus 10 forms a functional film by feeding the substrate Z out of a substrate roll 32 formed by winding a long substrate Z into a roll and transporting it in the longitudinal direction. This is an apparatus for forming a film by so-called roll-to-roll, in which the substrate Z (that is, a functional film) is wound into a roll shape.

  A film forming apparatus 10 shown in FIG. 1 is an apparatus capable of forming a film by plasma CVD on a substrate Z, and includes a vacuum chamber 12 and an unwinding chamber 14 formed in the vacuum chamber 12. The film forming chamber 18 and the drum 30 are configured.

  In the film forming apparatus 10, the long substrate Z is supplied from the substrate roll 32 of the unwind chamber 14 and is transported in the longitudinal direction while being wound around the drum 30, while the film is formed in the film forming chamber 18. Then, it is wound around the winding shaft 34 again in the unwinding chamber 14 (winded in a roll shape).

The drum 30 is a cylindrical member that rotates counterclockwise in the drawing around the center line.
The drum 30 wraps the substrate Z guided by a guide roller 40a of the unwind chamber 14 described later along a predetermined path around a predetermined area of the peripheral surface and conveys the substrate Z in the longitudinal direction while holding it at a predetermined position. It is conveyed into the film chamber 18 and sent again to the guide roller 40b in the unwind chamber 14.

  Here, the drum 30 also functions as a counter electrode of a shower electrode 20 in the film forming chamber 18 described later (that is, the drum 30 and the shower electrode 20 constitute an electrode pair), and is grounded (grounded). Has been.

If necessary, the drum 30 may be connected to a bias power source for applying a bias to the drum 30. Alternatively, the ground and the bias power supply may be connected to be switchable.
As the bias power source, all known power sources such as a high frequency power source and a pulse power source for applying a bias, which are used in various film forming apparatuses, can be used.

The unwinding chamber 14 includes an inner wall surface 12a of the vacuum chamber 12, a peripheral surface of the drum 30, and partition walls 36a and 36b extending from the inner wall surface 12a to the vicinity of the peripheral surface of the drum 30.
Here, the tips of the partition walls 36a and 36b (opposite to the inner wall surface of the vacuum chamber 12) are close to the peripheral surface of the drum 30 to a position where they cannot contact the substrate Z to be transported, The film forming chamber 18 is separated from the film forming chamber 18 in a substantially airtight manner.

  Such an unwinding chamber 14 includes the above-described winding shaft 34, guide rollers 40 a and 40 b, a rotating shaft 42, and a vacuum exhaust means 46.

  The guide rollers 40a and 40b are normal guide rollers that guide the substrate Z along a predetermined transport path. The take-up shaft 34 is a well-known long take-up shaft for taking up the film-formed substrate Z.

In the illustrated example, a substrate roll 32 formed by winding a long substrate Z into a roll is mounted on a rotating shaft 42. When the substrate roll 32 is mounted on the rotating shaft 42, the substrate Z is passed through a predetermined path that reaches the winding shaft 34 through the guide roller 40a, the drum 30, and the guide roller 40b (see FIG. Inserted).
In the film forming apparatus 10, the feeding of the substrate Z from the substrate roll 32 and the winding of the film-formed substrate Z on the winding shaft 34 are performed in synchronization, and the long substrate Z is transferred along a predetermined transport path. The film is formed in the film forming chamber 18 while being conveyed in the longitudinal direction.

  The vacuum exhaust means 46 is a vacuum pump for reducing the pressure in the unwinding chamber 14 to a predetermined degree of vacuum. The vacuum exhaust means 46 makes the inside of the unwinding chamber 14 a pressure (degree of vacuum) that does not affect the pressure in the film forming chamber 18 (film forming pressure).

In the transport direction of the substrate Z, a film forming chamber 18 is disposed downstream of the unwind chamber 14.
The film forming chamber 18 includes an inner wall surface 12 a, a peripheral surface of the drum 30, and partition walls 36 a and 36 b extending from the inner wall surface 12 a to the vicinity of the peripheral surface of the drum 30.
In the film forming apparatus 10, the film forming chamber 18 forms a film on the surface of the substrate Z by CCP (Capacitively Coupled Plasma) -CVD as an example. Means 58, high frequency power supply 60, and vacuum exhaust means 62 are included.

  The shower electrode 20 constitutes a pair of electrodes together with a drum when forming a film by CCP-CVD in the film forming apparatus 10, and from a through hole 22 c formed on the gas supply surface 22 a of the shower plate 22. A source gas is supplied between the drum 30 and the shower electrode 20 (shower plate 22). The shower electrode 20 includes a shower plate (gas supply electrode) 22 and a base 24.

The base 24 is formed of a conductive member, and is a casing (box) having one surface open. For example, the base 24 has a substantially rectangular parallelepiped shape with one surface open.
Further, a shower plate 22 is disposed on the open surface of the base 24 so as to cover the opening, and together with the shower plate 22, a hollow portion is formed inside. The base 24 and the shower plate 22 are electrically connected.

A source gas supply means 58 is connected to the base 24, and the source gas from the source gas supply means 58 flows into the hollow portion.
The base 24 is connected to a high frequency power supply 60.

  The material for forming the base 24 is not particularly limited, and various known conductive materials such as stainless steel, iron, or a plated product can be used.

2A is a sectional view conceptually showing an example of a shower plate manufactured by the manufacturing method of the present invention, and FIG. 2B is an enlarged sectional view of a part of the shower plate shown in FIG. It is.
The shower plate 22 is an aluminum plate-like member, and is held by the base 24 with the gas supply surface 22 a, which is one maximum surface, facing the peripheral surface of the drum 30.
A large number of through holes 22c are formed on the entire surface of the gas supply surface 22a. The through hole 22c communicates with the hollow portion. The gas supply surface 22 a is curved in a concave shape so as to follow the peripheral surface of the drum 30.

  Further, as shown in FIG. 2B, an aluminum sprayed film 22e is formed on the gas supply surface 22a of the shower plate 22 to be roughened. By forming a sprayed film 22e on the gas supply surface 22a facing the drum 30 (substrate Z) and roughening the surface, the film deposited on the gas supply surface 22a is prevented from peeling during film formation. be able to.

  Further, the roughening by the sprayed film 22e is easier to increase the surface roughness than the roughening by blasting. Therefore, it is possible to suppress the peeling of the film-formed material more suitably than the surface roughened by the blast treatment.

Moreover, in a film forming apparatus that continuously forms a film while winding a long substrate Z around a drum 30 and transporting it in the longitudinal direction like the film forming apparatus 10 in the illustrated example, the shower plate 22 Since a large amount of film deposits are deposited on the surface, peeling of the film deposits is likely to occur.
On the other hand, since the shower plate 22 manufactured by the manufacturing method of the present invention can suitably suppress the peeling of the film deposited on the surface, the long substrate Z as in the film forming apparatus 10 in the illustrated example. Can be suitably used in a film forming apparatus for continuously forming a film while winding the film around a drum 30 and transporting the film in the longitudinal direction.

Here, as the sprayed film 22e, a metal sprayed film made of any of aluminum, aluminum alloy, titanium, magnesium, and stainless steel can be used.
Forming a metal sprayed film as the sprayed film 22e is less expensive than forming a ceramic sprayed film, and the cost can be reduced. Further, it is preferable to form a metal sprayed film made of any of aluminum, aluminum alloy, titanium, and magnesium as the sprayed film 22e in that an oxide film can be formed by a plasma oxidation process described later.
Further, the stainless metal sprayed film is preferable in that it does not need to form the oxide film 22d because it has corrosion resistance.

Further, an alumina ceramic sprayed film can also be used as the sprayed film 22e.
The alumina ceramics sprayed film is also preferable in that it has corrosion resistance, so that it is not necessary to form the oxide film 22d, and since it is insulative, abnormal discharge from the shower plate can be suppressed.
The sprayed film 22e is formed by a plasma spraying process. Therefore, the through hole 22c is not clogged. This will be described in detail later.

  An aluminum oxide film 22d is formed on the gas supply surface 22a and the surface of the through hole 22c of the shower plate 22. By covering the surface of the shower plate 22 with an insulating oxide film 22d, it is possible to prevent abnormal discharge from occurring from the shower plate 22. Moreover, it can prevent that the shower plate 22 contacts with source gas and the shower plate 22 corrodes.

In the present invention, the oxide film 22d can be formed by various known methods such as anodizing or thermal spraying of alumina ceramics. Preferably, the oxide film 22d is formed on the surface of the shower plate 22 by plasma oxidation. Form.
Here, the plasma oxidation process is an anodization process using plasma. For example, the shower plate 22 for forming the oxide film 22d is immersed in an electrolyte containing a silicate or a zirconium salt, and the shower plate 22 is an anode. And using a metal plate facing the anode as a cathode, a pulse voltage is applied between the anode and the cathode to generate a plasma discharge, and an oxide film (alumina ceramic layer when the base material is aluminum, This is a method of forming a magnesium oxide layer in the case of magnesium and a titanium oxide layer in the case of titanium.

When forming an oxide film on the roughened surface, if the roughness is large, the oxide film cannot be formed uniformly, and defects may occur. If there is a defect in the oxide film, abnormal discharge may occur during film formation.
On the other hand, even if the surface of the shower plate 22 (gas supply surface 22a) is roughened by forming the oxide film 22d by plasma oxidation, a film having a uniform thickness is formed along the unevenness. A film having a uniform thickness can also be formed on the inner wall of the through hole 22c.
In the illustrated example, the oxide film 22d is formed on the surfaces of the gas supply surface 22a and the through hole 22c of the shower plate 22. However, the present invention is not limited to this, and the oxide film is formed on the entire surface of the shower plate 22. May be formed.

  In addition, the forming material (base material) of the shower plate 22 is not particularly limited as long as it is a conductive material, but any of aluminum, an aluminum alloy, magnesium, and titanium is preferable. By forming the shower plate 22 from these materials, a uniform and defect-free oxide film 22d can be formed on the surface by plasma oxidation, which is preferable in terms of suppressing the occurrence of abnormal discharge, and is lightweight. It is preferable because it is easy to handle.

  Further, the center line average roughness of the gas supply surface 22a is preferably 5 μm or more. By setting the surface roughness of the gas supply surface 22a to 5 μm or more, it is possible to prevent the film from being peeled off. Further, by forming the oxide film 22d by plasma oxidation treatment, a film having a uniform thickness can be formed even if the surface roughness is 5 μm or more.

The center line average roughness of the gas supply surface 22a is more preferably 10 to 30 μm.
By setting the roughness of the gas supply surface 22a to 10 μm or more, it is possible to more suitably prevent the film deposition deposited on the surface of the gas supply surface 22a from being peeled off. It is possible to prevent adhesion and influence on the film formed on the substrate Z.
Moreover, the surface roughness of the gas supply surface 22a is preferably 30 μm or less in that the oxide film 22d can be formed more uniformly.
As the surface roughness of the gas supply surface 22a is increased, peeling of the deposited film can be suppressed. However, if the surface roughness is too rough, the oxide film 22d cannot be formed uniformly, and defects may occur, which may cause abnormal discharge during film formation. On the other hand, the abnormal discharge at the time of film-forming can be suppressed by making the surface roughness of the gas supply surface 22a into 30 micrometers or less.

The diameter of the through hole 22c is preferably 0.7 mm or less.
If the diameter of the through hole is increased, the through hole will not be clogged even if roughening is performed by blasting or arc spraying. However, if the through hole is enlarged, there is a possibility that electric discharge may occur in the through hole during film formation, which may affect the film formation.
On the other hand, by setting the diameter of the through hole 22c to 0.7 mm or less, it is possible to more reliably prevent discharge from occurring in the through hole 22c during film formation.
Moreover, it is preferable that the diameter of the through hole 22c be 0.3 mm or more in order to stably supply the source gas.

  Here, the manufacturing method of the gas supply electrode of the present invention will be described with reference to a flowchart showing an embodiment of the manufacturing method of the present invention shown in FIG. 3 and a cross-sectional view enlarging a part of the shower plate shown in FIG. This will be explained in more detail.

4A is a partially enlarged sectional view showing the shower plate 22 before the gas supply surface 22a is roughened, and FIG. 4B shows the shower plate 22 after the through hole 22c is formed. It is a partial expanded sectional view shown.
In the present embodiment, as shown in STEP 1 (S1) in FIG. 3, the through hole 22c is formed by drilling the gas supply surface 22a of the shower plate 22 shown in FIG. (B)).

  Here, when the gas supply surface 22a is formed into a curved surface like the shower plate 22 in the illustrated example, if the drilling is performed from the gas supply surface 22a side, the position of the hole is shifted or the drill is eccentric and damaged. There is a risk. Therefore, it is preferable to perform drilling from the surface opposite to the gas supply surface 22a.

  Next, as shown in STEP 2 (S2) of FIG. 3, plasma spraying is performed on the gas supply surface 22a of the shower plate 22 shown in FIG. 4B to form a sprayed film 22e (FIG. 4C). )).

Here, the plasma spraying process is performed by heating and melting the thermal spray material using plasma generated by flowing an inert gas such as argon as a heat source between the electrodes and discharging it to the base material (shower plate 22). The sprayed film 22e is formed by spraying.
As described above, when the sprayed film is formed by arc spraying, the diameter of the sprayed particles to be sprayed is large, so that the through hole is blocked. This is because the heating temperature for melting the thermal spray material is not high and the thermal spray material is not sufficiently dissolved.
On the other hand, in the plasma spraying process, the spray material is heated using plasma as a heat source, so that it can be heated to a higher temperature than other sprays such as arc spraying. Therefore, since the thermal spray material is sufficiently dissolved and sprayed on the base material as small thermal spray particles, the through hole 22c is not blocked and the thermal spray film can be densified.

  Next, as shown in STEP 3 (S3) of FIG. 3, plasma oxidation is performed on the shower plate 22 shown in FIG. 4C to form an oxide film 22d on the gas supply surface 22a and the through hole 22c (FIG. 3). 4 (D)).

  As described above, in the present invention, after drilling with a drill to form a large number of through holes 22c, a sprayed film is formed on the gas supply surface 22a and roughened by plasma spraying, and then plasma oxidation is performed. Thus, an oxide film 22d is formed on the surface, and the shower plate 22 is manufactured.

As described above, when a film is formed by plasma CVD, the film is deposited not only on the substrate Z but also on the electrode for film formation. Therefore, a part of the film deposited on the electrode is an electrode. May be peeled off and attached to the substrate Z.
Therefore, for example, as in Patent Document 1, the surface of the electrode is roughened to improve the adhesion between the electrode and the film, thereby preventing the film deposited on the electrode from peeling from the electrode. ing.

However, if the blasting process is performed after the through hole is formed in the shower plate, there is a possibility that the particles used for the blasting process are clogged in the through hole. Further, even when the surface is roughened by forming a sprayed film by arc spraying, there is a possibility that the sprayed sprayed particles are clogged in the through holes.
When a film is formed using a shower plate with clogged through holes, the gas flow rate and pressure become unstable, so a high-quality film cannot be formed or plasma cannot be generated. The problem that the film cannot be formed occurs.

In addition, when forming a through hole after roughening the surface (gas supply surface) of the shower plate, if drilling is performed from the roughened surface, the position of the hole will be There is a risk that the drill may be displaced, or the drill may be eccentric and damaged.
Moreover, when forming a through-hole after forming a thermal spray film and roughening, there exists a possibility that a thermal spray film may crack (peel) at the interface of a thermal spray film and a base material. When the sprayed film is cracked, the smooth surface of the base material is exposed, so that the deposited film cannot be prevented from peeling off during film formation.

  On the other hand, in the manufacturing method of the present invention, since a large number of through holes 22c are formed by drilling with a drill, a thermal spray film is formed on the gas supply surface 22a and roughened by plasma spraying. The through hole 22c is not clogged, and when the through hole 22c is formed, the position of the hole is not shifted, and the drill is not eccentric and damaged. Further, the sprayed film is not broken. Therefore, when film formation is performed using the shower plate 22 manufactured by the manufacturing method of the present invention, the film deposited on the gas supply surface 22a of the shower plate 22 peels off and adheres to the substrate Z. Since it can be suppressed and the source gas can be stably supplied, a high-quality film can be formed on the substrate Z.

The source gas supply means 58 is a known gas supply means used in a vacuum film forming apparatus such as a plasma CVD apparatus, and supplies the source gas into the shower electrode 20 (hollow part).
As described above, a large number of through holes 22c are formed on the surface of the shower electrode 20 (shower plate 22) facing the drum 30 and communicate with the hollow portion. Therefore, the source gas supplied to the shower electrode 20 is introduced between the shower electrode 20 and the drum 30 from the through hole 22c.

The high frequency power source 60 is a power source that supplies plasma excitation power to the shower electrode 20. As the high-frequency power supply 60, all known high-frequency power supplies used in various plasma CVD apparatuses can be used.
Further, the vacuum evacuation means 62 evacuates the inside of the film forming chamber 18 to maintain a predetermined film forming pressure for forming a gas barrier film by plasma CVD, and is used in a vacuum film forming apparatus. This is a known evacuation means.

In the film forming apparatus using the gas supply electrode of the present invention, the film forming method in the CVD film forming chamber is not limited to the CCP-CVD in the illustrated example, but may be ICP (Inductively Coupled Plasma) -CVD, Other known CVD such as microwave CVD, Cat (catalytic catalyst) -CVD, thermal CVD, etc. can be used.
In the film forming apparatus using the gas supply electrode of the present invention, the film formed in the CVD film forming chamber is not particularly limited, and any film that can be formed by CVD can be used.

  As mentioned above, although the manufacturing method of the gas supply electrode of this invention was demonstrated in detail, this invention is not limited to the above-mentioned example, Even if various improvements and changes are performed in the range which does not deviate from the summary of this invention. Of course it is good.

Hereinafter, the present invention will be described in more detail by showing specific examples of the present invention.
[Example 1]
The shower plate 22 shown in FIG. 2 was manufactured.

The shower plate 22 was made of aluminum, and the thickness was 10 mm at the thinnest part and 40 mm at the thickest part.
<STEP1>
A through hole 22c having a diameter of 0.5 mm was formed on the entire surface of the gas supply surface 22a of the shower plate 22 with a super steel drill.

<STEP2>
By plasma spraying, a sprayed film 22e was formed on the gas supply surface 22a to be roughened. Aluminum was used as the thermal spray material.

<STEP3>
After the sprayed film 22e was formed, plasma oxidation treatment was performed on the entire surface of the shower plate 22 to form a 30 μm A1203 oxide film 22d.
When the surface roughness of the gas supply surface 22a after processing was measured with a roughness meter (Surfcom, manufactured by Tokyo Seimitsu), the center line average roughness was 15 μm.

Microscopic observation was performed after processing to evaluate the state of the through hole and the state of the oxide film.
Through hole Regarding the state of the through hole, the case where all the through holes are not clogged: ○;
When clogging occurred in more than half of the through-holes, ×;
As a result, the evaluation was good.
Oxide film Also, regarding the state of the oxide film, ○
△ if the oxide film has some defects
The case where there was a defect in the oxide film was indicated as x;
As a result, the evaluation was good.

Next, the manufactured shower plate was attached to the film forming apparatus 10 of FIG. 1 to form a film.
As the substrate Z, a PET film (Toyobo Cosmo Shine A4300 100 μm thickness) was used.
As the source gas, silane gas (SiH ₄ ), ammonia gas (NH ₃ ), and nitrogen gas (N ₂ ) were used.
The film forming pressure was 100 Pa.
A drum having a diameter of 1000 mm was used as the drum 30.
Further, a high frequency power source having a frequency of 13.56 MHz was used as the high frequency power source 60 connected to the shower electrode 20, and the plasma excitation power supplied to the shower electrode 20 was set to 2 kW.
The film thickness of the functional film (silicon nitride film) to be formed was 50 nm.
Under such conditions, the functional film was formed on the substrate Z for 60 minutes in the film forming apparatus 10.

After the film formation was completed, the gas supply surface 22a of the shower plate 22 was observed to evaluate the state of peeling of the film (peeling).
○ when the film is not adhered and peeled;
The case where peeling of the film formed occurred was indicated as x;
As a result, the evaluation was good.
Further, the gas supply surface 22a after film formation was observed to evaluate whether or not abnormal discharge occurred (abnormal discharge).
○ when there is no evidence of abnormal discharge
△ when there is a trace of abnormal discharge.
The case where a trace of abnormal discharge was observed was indicated as x;
As a result, the evaluation was good.

[Example 2]
In STEP 3, a shower plate was manufactured in the same manner as in Example 1 except that an oxide film was formed by alumite treatment.
When the surface roughness of the gas supply surface was observed in the same manner as in Example 1, the center line average roughness was 15 μm.
Moreover, when the state of the through hole was evaluated in the same manner as in Example 1, the evaluation was “◯”. Further, when the state of the oxide film was evaluated, some defects were observed, and the evaluation was “Δ”.
Further, in the same manner as in Example 1, the manufactured shower plate was attached to a film forming apparatus to form a film.
After the film formation was completed, evaluation of peeling of the film-formed product was performed in the same manner as in Example 1. The evaluation was “◯”. Further, when the abnormal discharge was evaluated, a trace of arc discharge was observed, and the evaluation was “Δ”.

[Comparative Example 1]
In STEP 2, a shower plate was manufactured in the same manner as in Example 1 except that arc spraying was performed instead of plasma spraying to form a sprayed film.
When the surface roughness of the gas supply surface was observed in the same manner as in Example 1, the center line average roughness was 20 μm.
Moreover, when the state of the through hole was evaluated in the same manner as in Example 1, almost all of the through holes were clogged with the sprayed film, and the evaluation was “x”. Moreover, when the state of the oxide film was evaluated, the evaluation was “◯”.
Similarly to Example 1, when the produced shower plate was attached to a film forming apparatus and film formation was performed, the gas flow rate and pressure could not be adjusted, and plasma could not be generated. could not.

[Comparative Example 2]
In STEP 2, a shower plate was manufactured in the same manner as in Example 1 except that instead of plasma spraying, the surface was roughened by blasting. The blast treatment was performed by using # 80 alumina beads as the granules and spraying the granules with 6 kgf / cm ² of compressed air.
Similar to Example 1, when the surface roughness of the gas supply surface was observed, the center line average roughness was 10 μm.
Further, as in Example 1, when the state of the through hole was evaluated, about half of the through holes were clogged with alumina beads, and the evaluation was “x”. Moreover, when the state of the oxide film was evaluated, the evaluation was “◯”.
Similarly to Example 1, when the produced shower plate was attached to a film forming apparatus and film formation was performed, the gas flow rate and pressure could not be adjusted, and plasma could not be generated. could not.

[Comparative Example 3]
A shower plate was manufactured in the same manner as in Example 1 except that the sprayed film of STEP 1 was not formed (roughened).
Similarly to Example 1, when the surface roughness of the gas supply surface was observed, the center line average roughness was 2 μm.
Moreover, when the state of the through hole was evaluated in the same manner as in Example 1, the evaluation was “◯”. Moreover, when the state of the oxide film was evaluated, the evaluation was “◯”.
Further, in the same manner as in Example 1, the manufactured shower plate was attached to a film forming apparatus to form a film.
After the film formation was completed, the peel was evaluated in the same manner as in Example 1. As a result, the film was peeled off, and the evaluation was “x”. Moreover, when abnormal discharge was evaluated, evaluation was "(circle)".
The evaluation results are shown in Table 1 below.

As shown in Table 1 above, in Examples 1 and 2 of the present invention in which a sprayed film was formed by plasma spraying after drilling, there was no peeling of the deposited film.
Further, by forming the oxide film by plasma oxidation treatment, a uniform oxide film having no defects can be formed, and abnormal discharge can be prevented.

On the other hand, in Comparative Example 1 in which the sprayed film is formed by arc spraying and in Comparative Example 2 in which the surface is roughened by blasting, clogging occurs in the through hole, and film formation cannot be performed. . In Comparative Example 3 in which no roughening was performed, the deposited film was peeled off during film formation.
From the above results, the effect of the present invention is clear.

DESCRIPTION OF SYMBOLS 10 Film-forming apparatus 12 Vacuum chamber 12a Inner wall surface 14 Unwinding room 18 Film-forming room 20 Shower electrode 22 Shower plate 22a Gas supply surface 22c Through-hole 22d Oxide film 22e Thermal spray film 24 Base 30 Drum 32 Substrate roll 34 Winding shaft 36 Partition 40 Guide roller 42 Rotating shaft 46, 62 Vacuum exhaust means 58 Raw material gas supply means 60 High frequency power supply Z substrate

Claims (11)

A method for producing a gas supply electrode having a plurality of through holes used in a plasma CVD apparatus,
Performing a hole drilling process to form the plurality of through holes; and
A method for producing a gas supply electrode, comprising: a spraying step of forming a sprayed film on a supply surface facing a plasma generation region by a plasma spraying process after the hole forming step.   The method for producing a gas supply electrode according to claim 1, further comprising a film forming step of forming an oxide film on at least the supply surface and the surface of the through hole after the spraying step.   The method for producing a gas supply electrode according to claim 2, wherein the film forming step performs plasma oxidation to form an oxide film.   The method for producing a gas supply electrode according to any one of claims 1 to 3, wherein the sprayed film is a metal sprayed film made of aluminum, aluminum alloy, titanium, magnesium, or stainless steel.   The method for manufacturing a gas supply electrode according to claim 1, wherein the sprayed film is an alumina ceramic sprayed film.   The method for producing a gas supply electrode according to any one of claims 1 to 5, wherein a center line average roughness of the supply surface is 5 µm or more.   The method for producing a gas supply electrode according to claim 6, wherein a center line average roughness of the supply surface is 10 to 30 μm.   The method for producing a gas supply electrode according to any one of claims 1 to 7, wherein a base material of the gas supply electrode is made of any one of aluminum, an aluminum alloy, magnesium, and titanium.   The method for manufacturing a gas supply electrode according to claim 1, wherein a diameter of the through hole is 0.7 mm or less.   The method for producing a gas supply electrode according to claim 1, wherein the plasma CVD apparatus forms a film on the substrate by plasma CVD while conveying a long substrate in the longitudinal direction.   The method of manufacturing a gas supply electrode according to claim 10, wherein the plasma CVD apparatus performs film formation while the substrate is wound around a predetermined area of a circumferential surface of a cylindrical drum and conveyed.

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