JP2013209691A - Method and apparatus for producing functional film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for producing a functional film which prevents deterioration in film quality caused by particles of reaction products adhered to members around a substrate, and which can efficiently and stably form the functional film capable of exhibiting objective functions.SOLUTION: A position at which raw material gas is introduced into a shower electrode is switched between both an end side and a central part side in the substrate width direction.

Description

  The present invention relates to a method and apparatus for producing a functional film for forming a film on a substrate by CVD.

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.

In order to efficiently form a film while ensuring high productivity by a vacuum film forming method, it is preferable to continuously form a film on a long substrate.
As an apparatus for carrying out such a film forming method, a supply roll formed by winding a long base material (web-shaped base material) in a roll shape, and a winding for winding a film-formed base material in a roll shape. A so-called roll-to-roll film forming apparatus using a take-off roll is known. This roll-to-roll film forming apparatus inserts a long base material from a supply roll to a take-up roll through a predetermined path passing through a film forming position (film forming region) for forming a film on the base material. The film is continuously formed on the substrate to be conveyed at the film forming position while the feeding of the base material from the supply roll and the winding of the film-formed base material by the winding roll are performed in synchronization. .

By the way, when the functional film is formed on the base material by the vacuum film forming method, not only the base material but also the base material supporting member that supports the base material and the base material such as a mask member that defines the film forming region Since the plasma and the raw material gas are also in contact with the members arranged around the substrate, it is inevitable that the reaction product formed at the time of film formation adheres to the peripheral members. The reaction product attached to the members around the substrate is deposited as the film is formed, peeled off, or etched into plasma to form particles, which degrades the quality of the formed film. It causes the quality of the product to deteriorate.
Therefore, in order to prevent deterioration of the film quality caused by the reaction product particles deposited on the peripheral members, it is possible to prevent plasma and source gas from contacting the peripheral members of the base material. Prevention of deposition of reaction products on the member is performed.

  For example, in Patent Document 1, when a gas passage is formed in a region extending from the lower side of the base material placement unit to the periphery of the side surface and purge gas (inert gas) is introduced into the gas passage, the purge gas is supplied to the base material placement unit. It is configured so as to be ejected to the peripheral space of the substrate mounting surface of the substrate, preventing the plasma and source gas from flowing into the region other than the film formation region, and preventing the reaction product from being deposited on the peripheral members. It is described.

  Further, in Patent Document 2, the outer peripheral portion of the gas supply portion on the surface facing the base material stage is positioned outside the outer peripheral end portion position of the target substrate in the in-plane direction of the target substrate. And a shielding member protruding in the direction of the substrate stage, and exhausting the source gas to the outside of the shielding unit to suppress the contact of the plasma and the source gas with the surrounding member of the substrate, and the surrounding member Describes that the reaction product is prevented from being deposited.

JP 2000-54137 A JP 2010-283092 A

However, when the inert gas is blown to the end of the film formation region to restrict the diffusion of the plasma and the raw material gas, the inert gas is mixed with the raw material gas in the film formation region to form a film on the substrate. There was a problem that the film quality of the film deteriorated.
In addition, since the roll-to-roll film forming apparatus performs film formation when a continuously transported substrate passes through the film forming region, the material gas is discharged from the film forming region, and the plasma In addition, it is difficult to have a configuration in which the raw material gas does not enter the surrounding members. In addition, since the roll-to-roll film forming apparatus continuously forms a film for a long time, even if the source gas is discharged from the film forming area, the reaction product is deposited on a shielding part or the like surrounding the film forming area. It is inevitable to do.

  An object of the present invention is to solve the above-mentioned problems of the prior art, and in a roll-to-roll film forming apparatus for continuously forming a film on a long base material by plasma CVD, A method for producing a functional film capable of efficiently and stably forming a functional film capable of preventing the deterioration of film quality due to reaction product particles adhering to peripheral members and expressing a target function And providing a manufacturing apparatus.

  In order to solve the above problems, the present invention is based on plasma CVD using a film forming means having an electrode pair arranged so as to sandwich a substrate to be conveyed while conveying a long substrate in the longitudinal direction. In a method for producing a functional film for forming an inorganic film on a base material in a film formation region defined by mask members disposed on both ends of the base material in the width direction perpendicular to the transport direction of the base material The base material is one electrode of the electrode pair, and the introduction position of the raw material gas into the shower electrode that supplies the raw material gas into the film formation region is set to the both ends of the base material in the width direction of the base material. After the first film forming step for forming a film on the substrate and after the first film forming step, the introduction position of the source gas into the shower electrode is set to the center side from the introduction position in the first film forming step. And a second film forming step for forming the film. There is provided a method for producing a potential film.

Here, the source gas is a gas containing at least silane gas and nitrogen gas, the inorganic film to be formed is a silicon nitride film, and the silicon nitride film to be formed on the mask member in the first film forming step is used. Preferably, the atomic weight ratio N / Si is smaller than 0.95, and the atomic weight ratio N / Si of the silicon nitride film formed on the mask member in the second film forming step is larger than 0.95.
Moreover, it is preferable that the flow rate of the source gas in the first film formation step is larger than the flow rate of the source gas in the second film formation step.
Further, it is preferable to perform film formation by alternately repeating the first film formation step and the second film formation step.

  In order to solve the above problem, the present invention is directed to plasma using a film forming means having an electrode pair disposed so as to sandwich a substrate to be conveyed while conveying a long substrate in the longitudinal direction. An apparatus for producing a functional film for depositing an inorganic film on a base material by CVD, on both ends of the base material in the width direction orthogonal to the transport direction of the base material in the region where the electrode pair is disposed A mask member arranged to define a film formation region, one electrode of the electrode pair, a diffusion chamber for diffusing the introduced source gas, a plurality of through holes communicating from the diffusion chamber to the film formation region, and diffusion A shower electrode having at least three inlets formed at different positions in the width direction of the base material for introducing the source gas into the chamber, and the source gas is supplied into the diffusion chamber from at least one inlet of the shower electrode Raw material gas supply means; Material gas supplying means is to provide an apparatus for manufacturing a functional film characterized by having a introducing position switching means for switching the inlet when supplying the raw material gas to the shower head electrode.

Here, it is preferable that the introduction position switching means switches the introduction ports for supplying the source gas between the introduction ports on both ends in the width direction of the base material and the introduction ports excluding the introduction ports on both ends.
Moreover, it is preferable that the introduction position switching means switches the introduction port for supplying the raw material gas from the introduction ports on both ends in the width direction of the base material to the introduction ports excluding the introduction ports on both ends.
The shower electrode has four introduction ports, and the introduction position switching means preferably switches the introduction port between the two outer introduction ports in the width direction and the two inner introduction ports.

The source gas supply means preferably changes the supply amount of the source gas in accordance with the switching of the source gas introduction port by the introduction position switching means.
The height of the diffusion chamber of the shower electrode in the direction perpendicular to the surface of the substrate is preferably 3 mm or less.
Moreover, it is preferable that the other electrode of an electrode pair is a cylindrical drum electrode which winds and conveys a base material to the predetermined area | region of a surrounding surface.

  According to the present invention, the composition of the reaction product deposited on the peripheral members is controlled by switching the introduction position of the source gas into the shower electrode between the both end sides and the center side in the base material width direction. Thus, since the composition can be made difficult to peel off and difficult to be etched, reaction product particles caused by peeling of the reaction product or etching by plasma can be reduced. Accordingly, it is possible to efficiently and stably form a functional film capable of preventing the quality of the functional film from being deteriorated by mixing particles into the formed functional film and expressing the target function.

It is a figure which shows notionally an example of the manufacturing apparatus which enforces the manufacturing method of the functional film of this invention. It is the elements on larger scale which show a part of manufacturing apparatus shown in FIG.

  Hereinafter, the functional film manufacturing method and manufacturing apparatus of the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, an example of the functional film manufacturing apparatus of this invention which implements the manufacturing method of the functional film of this invention is shown notionally. In FIG. 1, a part of the shower electrode 20 is shown in cross section.
In the functional film manufacturing apparatus 10 (hereinafter also referred to as “film forming apparatus”) shown in FIG. 1, the shower electrode 20 has a plurality of source gas inlets, and the source gas introduction position to the shower electrode 20 is determined. Except for the introduction position switching means 24 for switching, this is a known CCP-CVD roll-to-roll film forming apparatus.

The film forming apparatus 10 of the illustrated example supplies a raw material gas containing silane gas and ammonia gas to a film forming region while conveying a long base material Z (film raw fabric) in the longitudinal direction, A functional film is manufactured by forming (manufacturing / forming) a silicon nitride film on the surface by plasma CVD.
Further, the film forming apparatus 10 sends out the base material Z from the base material roll 32 formed by winding the long base material Z into a roll shape, and forms the functional film while conveying it in the longitudinal direction. Is a device that performs film formation by so-called roll-to-roll (roll-to-roll).

  A film forming apparatus 10 shown in FIG. 2 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. And a film forming chamber 18 and a drum 30.

  In the film forming apparatus 10, the long base material Z is supplied from the base material roll 32 of the unwinding chamber 14 and is transported in the longitudinal direction while being wound around the drum 30. The film is formed, and then again wound around the winding shaft 34 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 conveys the base material Z guided by a guide roller 40a of the unwinding chamber 14 to be described later in a predetermined path around the predetermined area of the peripheral surface in the longitudinal direction while holding it at a predetermined position, The film is transferred into the film forming chamber 18 and sent again to the guide roller 40 b in the unwinding 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 ends 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 conveyed, 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 base material 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 example of illustration, the base material roll 32 formed by winding the elongate base material Z in roll shape is attached to the rotating shaft 42. When the substrate roll 32 is mounted on the rotary 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. (Inserted).
In the film forming apparatus 10, the feeding of the base material Z from the base material roll 32 and the winding of the film-formed base material Z on the take-up shaft 34 are performed in synchronization, and a long base material Z is predetermined. The film is formed in the film forming chamber 18 while being transported in the longitudinal direction along the transport path.

  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).

A film forming chamber 18 is disposed downstream of the unwinding chamber 14 in the transport direction of the substrate Z.
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 silicon nitride film on the surface of the substrate Z by CCP (Capacitively Coupled Plasma) -CVD using a gas containing silane gas and ammonia gas as a source gas. The film is formed, and includes a shower electrode 20, a mask member 22, an introduction position switching unit 24, a source gas supply unit 58, a high frequency power source 60, and a vacuum exhaust unit 62.

FIG. 2 is a schematic view of the film forming apparatus 10 shown in FIG.
The shower electrode 20 is a film forming electrode that forms an electrode pair together with the drum 30 when the film forming apparatus 10 forms a film by CCP-CVD. In the illustrated example, the shower electrode 20 has, for example, a hollow, substantially rectangular parallelepiped shape having a diffusion chamber formed therein, and is disposed with the discharge surface, which is one maximum surface, facing the peripheral surface of the drum 30. In addition, a large number of through holes are formed on the entire discharge surface, which is the surface facing the drum 30. The shower electrode 20 generates plasma for film formation between the discharge surface and the peripheral surface of the drum 30 forming the electrode pair, thereby forming a film formation region.
In the illustrated example, as a preferred embodiment, the discharge surface of the shower electrode 20 is curved so as to be along the peripheral surface of the drum 30, but may be flat.

In addition, as shown in FIG. 2, an inlet for introducing the source gas supplied from the source gas supply means 58 into the interior (diffusion chamber) of the shower electrode 20 is provided on the surface opposite to the discharge surface. A plurality of base materials Z are arranged in the width direction (hereinafter also simply referred to as “width direction”).
In the illustrated example, four introduction ports are formed, which are two outer introduction ports 20a and 20d formed on both end sides in the width direction and two inner introduction ports 20b and 20c formed on the inner side. The outer channel 26L is connected to the outer inlets 20a and 20d, and the inner channel 28L is connected to the inner inlets 20b and 20c.
Further, the outer introduction ports 20a and 20d and the inner introduction ports 20b and 20c are formed at symmetrical positions in the center in the width direction.

Here, in the film forming apparatus 10 of the present invention, the introduction port used when introducing the source gas into the shower electrode 20 uses the outside introduction ports 20a and 20d by the introduction position switching means 24 described later. The inner introduction ports 20b and 20c are configured to be switchable.
This will be described in detail later.

In the illustrated example, four introduction ports are formed. However, the present invention is not limited to this, and the configuration includes three of the outer introduction ports 20a and 20d and one introduction port formed in the center. It is good. In the case of having three inlets, the inlet to be used may be switched between the outer inlets 20a and 20d and the central inlet.
Or you may have five or more inlets. Even in that case, it is only necessary to switch between the two inlets formed on both ends and the other inlets.

The height of the diffusion chamber formed in the shower electrode (width in the direction perpendicular to the discharge surface) is preferably 3 mm or less. In the film forming apparatus, since high power is applied to the shower electrode 20, abnormal discharge occurs when the height of the diffusion chamber is 3 mm or more. Occurrence of abnormal discharge can be prevented by setting the height of the diffusion chamber formed in the shower electrode to 3 mm or less.
Similarly, in order to prevent the occurrence of abnormal discharge, the diameters of the outer introduction ports 20a and 20d, the inner introduction ports 20b and 20c, and the diameter of the through holes formed in the discharge surface are preferably 3 mm or less. .
Moreover, in order to suppress abnormal discharge, the outer peripheral inlets 20a and 20d and the peripheral edges of the inner inlets 20b and 20c may be formed of an insulating member such as ceramic.

The mask member 22 is a plate-like member for defining a region where a film is formed in the width direction of the substrate Z, and is made of an insulator such as ceramics such as alumina.
As shown in FIG. 2, the mask members 22a and 22b are formed so as to cover the end of the drum 30 around which the base material Z is not wound and the end of the base material Z in the region where the shower electrode 20 is disposed. It is arrange | positioned at the both ends part side of the width direction of material, respectively. This prevents the plasma and the source gas from coming into contact with the end of the drum 30 and the end of the substrate Z during film formation, and the film is formed on the end of the drum 30 and the end of the substrate Z. Is prevented from accumulating.

The introduction position switching unit 24 is a part that switches an introduction port when the source gas supplied from the source gas supply unit 58 is introduced into the shower electrode 20.
The introduction position switching unit 24 is connected to an outer channel 26L and an inner channel 28L that are flow paths for supplying the source gas supplied from the source gas supply unit 58 into the shower electrode 20, and the source gas is supplied to the introduction position switching unit 24. The channel to be supplied is switched between the outer channel 26L and the inner channel 28L. Thereby, the introduction position where the source gas is introduced into the shower electrode 20 can be switched.
As the introduction position switching means 24, various known fluid line switching devices can be used.

  Here, the manufacturing method of the functional film of the present invention performed by switching the introduction position of the source gas to the shower electrode 20 by the introduction position switching means 24 will be described in more detail.

First, at the start of film formation, the introduction position switching means 24 selects the outer channel 26L connected to the outer introduction ports 20a and 20d, and feeds the source gas from the outer introduction ports 20a and 20d into the diffusion chamber in the shower electrode 20. The film is supplied and continuously formed on the substrate Z (first film forming step).
After the film formation is performed on the base material Z having a predetermined length in a state in which the source gas is supplied from the outer introduction ports 20a and 20d into the shower electrode 20, the introduction position switching means 24 performs the film formation. Then, switching to the inner channel 28L connected to the inner inlets 20b and 20c, the source gas is supplied from the inner inlets 20b and 20c to the diffusion chamber in the shower electrode 20 to continuously form the film on the substrate Z. Performed (second film forming step).

Here, the silane gas contained in the source gas is heavier and difficult to diffuse than other gases contained in the source gas. Further, as described above, the height of the diffusion chamber in the shower electrode 20 needs to be lowered in order to suppress abnormal discharge, and it is difficult to sufficiently diffuse the source gas. For this reason, the ratio of silicon in the film decreases as the film is formed at a position farther from the introduction port, and the ratio of silicon in the film increases as the film is formed at a position closer to the introduction port.
Accordingly, when the film is formed by the above method, the reaction product deposited on the mask member 22 is deposited on the mask member 22 because the source gas is introduced from a position close to the mask member 22 at the start of film formation. The reaction product on the mask member 22 side is a film having a high silicon ratio, and then the introduction position is switched and the source gas is introduced from a position far from the mask member 22 on the inner side. Becomes a film having a low silicon ratio.

Here, the larger the ratio of silicon in the film, the softer the silicon nitride film, and the more difficult it is to peel off from the mask member 22. In particular, even when expanded by heat, the difference in coefficient of thermal expansion from the mask member 22 is absorbed, and peeling can be prevented. However, a soft film is easily etched by plasma.
On the other hand, the smaller the ratio of silicon in the film, the harder the film, so that it is easier to peel off, but the plasma resistance is high and etching is difficult.

  Accordingly, the reaction product deposited on the mask member 22 when the film is formed by the above method is softer on the side close to the mask member 22 and thus is difficult to peel off, and the surface side is harder and therefore difficult to be etched. . Thereby, peeling of reaction products deposited on the mask member 22 and etching by plasma can be reduced, generation of particles due to peeling and etching can be reduced, and the quality of the functional film is deteriorated due to mixing of particles. Thus, it is possible to efficiently and stably form a functional film that can exhibit the target function.

  As described above, according to the manufacturing method of the present invention, when continuous film formation is performed in the roll-to-roll film forming apparatus, the introduction position switching means 24 causes the raw material gas to enter the shower electrode 20. By switching the introduction position, the composition of the reaction product deposited on the peripheral members such as the mask member 22 can be controlled in the laminating direction so that the composition is difficult to peel off and difficult to etch. Particles of the reaction product due to product peeling or plasma etching can be reduced.

Here, when the source gas is introduced from the outer introduction ports 20a and 20d (first film forming step), the atomic weight ratio N / Si of nitrogen and silicon of the reaction product (silicon nitride film) deposited on the mask member 22 Is 0.95 or less, and nitrogen of a reaction product (silicon nitride film) deposited on the mask member 22 when the source gas is introduced from the inner introduction ports 20b and 20c (second film formation step) And the atomic weight ratio N / Si of silicon is preferably larger than 0.95.
As a result, the composition of the reaction product to be deposited becomes more reliable, the mask member 22 side is soft and difficult to peel off, and the surface is hard and hard to be etched, so that particles due to peeling and etching can be reduced. It can prevent that the quality of a functional film falls by mixing.

Moreover, in the manufacturing method of the functional film of this invention, it is preferable to repeat a 1st film-forming step and a 2nd film-forming step.
When the film thickness of the hard film is increased, the film may be peeled off due to internal stress. Therefore, after the reaction product deposited on the mask member 22 is changed to a hard film in the second film forming step, the introduction position switching unit 24 switches the introduction position of the source gas again, and from the outer introduction ports 20a and 20d. The source gas is introduced into the shower electrode 20 to make the reaction product deposited on the mask member 22 into a soft film, and then the introduction position switching means 24 is used to switch the introduction position of the source gas, and the inner introduction port 20b. 20c, by introducing a source gas into the shower electrode 20 and using a reaction product surface deposited on the mask member 22 as a hard film, and alternately stacking a soft film and a hard film, the internal stress in the film Can be reduced to prevent the film from peeling off.

The source gas supply means 52 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 through the introduction position switching means.
As described above, a large number of through holes are formed on the surface of the shower electrode 20 facing the drum 30. Accordingly, the source gas supplied to the shower electrode 20 is introduced between the shower electrode 20 and the drum 30 through the through hole.

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.

  Next, the operation of the film forming apparatus 10 in FIG. 1 will be described.

  As described above, when the base roll 32 is loaded on the rotating shaft 42, the base Z is pulled out from the base roll 32, and the guide roller 40a, the winding roller 20, the drum 30, the peeling roller 22, and the guide roller. After passing through 40b, it passes through a predetermined conveying path that reaches the winding shaft 34.

When the substrate Z is inserted, the vacuum chamber 12 is closed, and the vacuum exhaust means 46 and 56 are driven to start exhausting the unwind chamber 14 and the film forming chamber 16.
When the unwinding chamber 14 and the film forming chamber 16 are evacuated to a predetermined vacuum level or less, the source gas supply unit 52 is then driven to supply the source gas to the film forming chamber 16. The driving is adjusted according to the predetermined pressure in the unwinding chamber 16.

  When the pressures in the unwinding chamber 14 and the film forming chamber 16 are stabilized at a predetermined pressure, the drum 30 and the like are started to rotate and the conveyance of the substrate Z is started. While being conveyed in the longitudinal direction, film formation on the substrate Z in the film formation chamber 16 is started.

Here, as described above, in the present invention, the source gas is supplied into the shower electrode 20 from the outer introduction ports 20a and 20b at the start of film formation. As a result, the reaction product deposited on the mask member 22 becomes a soft and difficult-to-peel film. After the film is formed on the base material Z having a predetermined length, the introduction position switching means 24 switches the source gas introduction position to the inner introduction ports 20b and 20c, so that the film is deposited on the mask member 22. The reaction product becomes a film that is hard and difficult to etch.
As a result, it is possible to reduce particles caused by peeling of reaction products deposited on the mask member 22 and etching by plasma, preventing the deterioration of the quality of the functional film due to the mixing of particles, and realizing the intended function. A functional film that can be formed can be formed efficiently and stably.

Here, in the above embodiment, a silicon nitride film is formed, and a reactive gas containing silane gas and ammonia gas is used as a source gas. However, the present invention is not limited to this, and an inorganic film to be formed is used. All known reaction gases according to the above can be used.
For example, when a silicon oxide film is formed as the inorganic film, silane gas and oxygen gas may be used as the reaction gas.

  As the inorganic film, any film that can be formed by CVD can be used. In particular, inorganic films such as silicon oxide, silicon oxynitride, aluminum oxide, and silicon nitride are preferably exemplified. In particular, it can be suitably applied to the formation of an amorphous silicon nitride film because it is easy to obtain a transparent and dense film.

  If necessary, various gases such as inert gas such as helium gas, neon gas, argon gas, krypton gas, xenon gas, radon gas, nitrogen gas, hydrogen gas, etc. may be used in combination with the reactive gas. .

The flow rate of the source gas supplied by the source gas supply means 58 is such that the composition N / Si of the functional film formed on the substrate Z is within a predetermined range according to the introduction position of the source gas of the shower electrode 20. It is preferable to change so that.
As described above, the raw material gas includes a plurality of types of gas, and the diffusibility differs depending on the type of gas. Therefore, the ratio of the source gas in the central portion in the width direction of the substrate Z is different between the case where the source gas is introduced from the outer introduction ports 20a and 20d and the case where the source gas is introduced from the inner introduction port. The composition of the film will also be different. Therefore, in order to keep the composition of the functional film formed on the substrate Z within a predetermined range when the source gas is introduced from the outer introduction ports 20a and 20d and when the source gas is introduced from the inner introduction port. According to the diffusibility of the source gas, the flow rate of the source gas may be changed between the case where the source gas is introduced from the outer introduction ports 20a and 20d and the case where the source gas is introduced from the inner introduction port.

  In this embodiment, the source gas contains silane gas and ammonia gas, and the diffusibility of the silane gas is low. Therefore, when the source gas is introduced from the outer introduction ports 20a and 20d, the source gas is introduced from the inner introduction ports 20b and 20c. What is necessary is just to increase the flow volume of source gas so that the quantity of the silane gas of the center part of the width direction may increase rather than the case where gas is introduce | transduced.

In 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 other CVD such as ICP-CVD, direct current (DC) plasma CVD, microwave plasma CVD, etc. Also available.
In particular, CCP-CVD can be performed for reasons such as being able to stably generate plasma over a wide range and being suitable for roll-to-roll, and being able to form a film on an insulating substrate by using an AC power source. The present invention can be preferably applied to a film forming apparatus.

  Further, in this embodiment, as a preferred embodiment, a long base material is wound around a drum while being transported in the longitudinal direction of the base material, and a so-called roll to roll (Roll to Roll) is performed. However, the present invention is not limited to this, and is a roll-to-roll apparatus, in which a plate-like electrode pair disposed facing each other is provided in the film forming chamber. A structure may be adopted in which a long base material is conveyed in the longitudinal direction and a raw material gas is supplied between the base material and the electrode to form a film by plasma CVD.

  As mentioned above, although the manufacturing method and manufacturing apparatus of the functional film of this invention were demonstrated in detail, this invention is not limited to the above-mentioned example, In the range which does not deviate from the summary of this invention, various improvement and change are made. Of course, you can do it.

  Hereinafter, the present invention will be described in more detail with reference to specific examples of the present invention.

[Example 1]
A silicon nitride film was formed as a gas barrier film on the substrate using the film forming apparatus shown in FIG.

As the substrate, a PET film having a width of 1000 mm and a thickness of 100 μm was used.
As the raw material gas, silane gas _(SiH 4), ammonia gas _(NH 3), it was used nitrogen gas _{(N 2).}
The film forming pressure was 40 Pa.
The shower electrode 20 has a width of 1000 mm, a diffusion chamber height of 2 mm, and an inlet diameter of 3 mm. The outer inlets 20 a and 20 d are positioned 450 mm from the center in the width direction, and the inner inlets 20 b and 20 c The position was 200 mm from the center in the width direction. That is, the distance between the outer inlets 20a and 20d was 900 mm, and the distance between the inner inlets 20b and 20c was 400 mm.
In addition, 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 3 kW.
As the drum 30, a drum having a diameter of 1000 mm and a width of 1050 mm was used. The drum 30 was grounded.
The mask member 22 has a width of 50 mm. The distance between the mask members 22a and 22b, that is, the film forming region in the width direction on the substrate Z was set to 950 mm.
The film thickness of the functional film (silicon nitride film) to be formed was 50 nm.

  The flow rate of the source gas is such that the element ratio N / Si of the functional film formed on the base material Z in the film formation region is in the range of 0.95 to 1.1. When the raw material gas is introduced from the inside, the flow rate of the silane gas is 100 sccm, the flow rate of the ammonia gas is 150 sccm, the flow rate of the nitrogen gas is 1000 sccm, and the raw material gas is introduced from the inner inlets 20b and 20c, Was 85 sccm, the flow rate of ammonia gas was 120 sccm, and the flow rate of nitrogen gas was 900 sccm.

  From the start of film formation to the position of 100 m on the substrate Z, the raw material gas was introduced from the outer introduction ports 20a and 20d, and from the position of 100 m to the end, the raw material gas was introduced from the inner introduction ports 20b and 20c.

Under such conditions, in the film forming apparatus 10, the functional film is formed on the substrate Z for 300 m, the film forming length (film forming distance) is 5 m, 50 m, 100 m, and 150 m. The number of particles per hour is detected by a particle counter (manufactured by INFICON) in the vicinity of the shower electrode 20 during film formation at a position of 200 m, a position of 250 m, and a position of 300 m, and the number of particles is 50 / Min or less was evaluated as good, 50 to 75 / min was acceptable, and 75 / min was unacceptable.
As a result of the evaluation, all of the positions from 5 m to 300 m were good.

[Example 2]
From the start of film formation to the position of 50 m of the substrate Z, the raw material gas is introduced from the outer introduction ports 20a and 20d, and from the position of 50 m to the position of 100 m, the raw material gas is introduced from the inner introduction ports 20b and 20c. The functional film was formed on the substrate Z and the particles were detected in the same manner as in Example 1 except that the position of the inlet was alternately changed every 50 m.
As a result of the evaluation, all of the positions from 5 m to 300 m were good.

[Comparative Example 1]
From the start to the end of film formation, a functional film was formed on the substrate Z and particles were detected in the same manner as in Example 1 except that the source gas was introduced from the outer introduction ports 20a and 20d.
As a result of the evaluation, it was good at the position of 5 m to 100 m, acceptable at the position of 150 m to 250 m, and not at the position of 300 m.
Further, when the composition of the reaction product deposited on the mask member 22 was analyzed by etching ESCA, the element ratio N / Si was 0.91.

[Comparative Example 2]
From the start to the end of film formation, a functional film was formed on the substrate Z and particles were detected in the same manner as in Example 1 except that the source gas was introduced from the inner inlets 20b and 20c.
As a result of the evaluation, it was good at the position of 5 m to 100 m and not at the position of 150 m to 300 m.
Further, when the composition of the reaction product deposited on the mask member 22 was analyzed by etching ESCA, the element ratio N / Si was 1.02.

[Comparative Example 3]
The same as in Example 1 except that the raw material gas was introduced from the inner inlets 20b and 20c from the start of film formation to the position of 50 m and the raw material gas was introduced from the outer inlets 20a and 20d from the position of 50 m to the end. Then, a functional film was formed on the substrate Z, and particles were detected.
As a result of the evaluation, it was good at a position of 5 m to 150 m, and not possible at a position of 200 m to 300 m.
The results are shown in Table 1.

  As shown in Table 1, at the start of film formation, the source gas is supplied into the shower electrode 20 from the outer introduction ports 20a and 20d, and then the introduction position is switched, and the source gas is supplied from the inner introduction ports 20b and 20c. In the present invention in which the film is formed by introduction, the composition of the reaction product deposited on the mask member 22 is a film that is soft and difficult to peel off on the mask member 22 side, and a film that is hard and difficult to etch on the surface side. Particles due to peeling or etching of reaction products deposited on the member 22 can be reduced. Thereby, it is possible to efficiently and stably form a functional film capable of preventing the particles from being mixed and deteriorating the quality of the functional film and expressing the intended function.

On the other hand, in Comparative Example 1, the reaction product deposited on the mask member 22 becomes a soft film, so that the number of particles due to etching increases as the reaction product accumulates on the mask member 22 after successive film formation. I know you do.
Further, in Comparative Example 2, the reaction product deposited on the mask member 22 becomes a hard film. Therefore, it can be seen that when the film formation progresses and the film thickness increases, peeling increases and particles increase rapidly.
In Comparative Example 3, it can be seen that the reaction product deposited on the mask member 22 has a hard film on the mask member 22 side and a soft film on the surface side, so that particles due to etching and peeling increase.
From the above results, the effects of the present invention are clear.

10 Functional film production equipment (film deposition equipment)
DESCRIPTION OF SYMBOLS 12 Vacuum chamber 12a Inner wall surface 14 Unwinding chamber 18 Deposition chamber 20 Shower electrode 20a, 20d Outer introduction port 20b, 20c Inner introduction port 22 Mask member 24 Introduction position switching means 26L Outer channel 28L Inner channel 30 Drum 32 Substrate roll 34 Winding shaft 36 Bulkhead 40 Guide roller 42 Rotating shaft 46, 62 Vacuum evacuation means 58 Source gas supply means 60 High frequency power supply Z Substrate

Claims (11)

While transporting a long base material in the longitudinal direction, a width perpendicular to the transport direction of the base material by plasma CVD using a film forming means having an electrode pair arranged so as to sandwich the base material to be transported In a film formation region defined by a mask member disposed on both ends of the substrate in the direction, a method for producing a functional film for forming an inorganic film on the substrate,
One electrode of the electrode pair, the introduction position of the source gas into the shower electrode that supplies the source gas into the film formation region, as the both ends of the substrate in the width direction of the substrate, A first film forming step for forming a film on a substrate;
After the first film formation step, the second film formation is performed on the base material with the introduction position of the source gas into the shower electrode being set to the center side from the introduction position in the first film formation step. And a method for producing a functional film.   The source gas is a gas containing at least a silane gas and a nitrogen gas, the inorganic film to be formed is a silicon nitride film, and the silicon nitride film formed on the mask member in the first film forming step And the atomic weight ratio N / Si of the silicon nitride film formed on the mask member in the second film forming step is greater than 0.95. A method for producing the functional film according to 1.   3. The method for producing a functional film according to claim 1, wherein a flow rate of the source gas in the first film formation step is larger than a flow rate of the source gas in the second film formation step.   The method for producing a functional film according to claim 1, wherein film formation is performed by alternately repeating the first film formation step and the second film formation step. An inorganic film is formed on the base material by plasma CVD using a film forming means having an electrode pair disposed so as to sandwich the base material to be transported while transporting a long base material in the longitudinal direction. A functional film manufacturing apparatus for performing
A mask member that is disposed on both ends of the base material in the width direction orthogonal to the transport direction of the base material in a region where the electrode pair is disposed, and that defines a film formation region;
One electrode of the electrode pair, a diffusion chamber for diffusing the introduced source gas, a plurality of through holes communicating from the diffusion chamber to the film formation region, and for introducing the source gas into the diffusion chamber A shower electrode having at least three inlets formed at different positions in the width direction of the substrate;
Source gas supply means for supplying source gas into the diffusion chamber from at least one inlet of the shower electrode;
An apparatus for producing a functional film, comprising: an introduction position switching means for switching an introduction port when the source gas supply means supplies a source gas to the shower electrode.   6. The introduction position switching unit according to claim 5, wherein the introduction position switching means switches the introduction ports for supplying the raw material gas between the introduction ports on both ends in the width direction of the substrate and the introduction ports excluding the introduction ports on both ends. Functional film production equipment.   The said introduction position switching means switches the introduction port which supplies raw material gas from the introduction port of the both ends part side of the width direction of the said base material to the introduction port except the introduction port of the both ends part side. Functional film manufacturing equipment.   The shower electrode has four introduction ports, and the introduction position switching means switches the introduction port between two outer introduction ports in the width direction and two inner introduction ports. The functional film production apparatus described in 1.   9. The functional film manufacturing apparatus according to claim 5, wherein the source gas supply unit changes a supply amount of the source gas in accordance with switching of the source gas introduction port by the introduction position switching unit.   The functional film manufacturing apparatus according to any one of claims 5 to 9, wherein a height of the diffusion chamber of the shower electrode in a direction perpendicular to the surface of the base material is 3 mm or less.   The film forming apparatus according to claim 5, wherein the other electrode of the electrode pair is a cylindrical drum electrode that winds and conveys the base material around a predetermined region of a peripheral surface.

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