JP2014167154A - Film deposition device and film deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently supply radicals on a substrate in a film deposition device for depositing a film on a substrate being conveyed using plasma ALD.SOLUTION: A film deposition device has a film deposition container, a conveying mechanism for conveying a substrate, plural plasma generation electrode plates, and injectors. The plasma generation electrode plate is an electrode plate provided along a substrate conveying path. Respective main surfaces of the electrode plates are opposed to a face of the substrate, and a current flows in a direction transverse to the substrate conveying path to form a magnetic field and generate a plasma. The injectors are spaced along the conveying path between the plasma generation electrode plate and the conveying path, so that radicals generated from the plasma are supplied to the substrate. The injectors respectively supply film depositing gas toward the substrate. Respective transverse portions of the plasma generation electrode plates at which the current flows to form the magnetic field are provided at the same positions as intervals between the injectors relative to a position along a conveying direction.

Description

  The present invention relates to a film forming apparatus and a film forming method for forming a thin film in units of atomic layers using a film forming gas and a reactive gas.

  Today, a film forming method by ALD (Atomic Layer Deposition) for forming a thin film in atomic layer units is known. In this ALD, a film having a structure in which a plurality of atomic layer units are stacked is formed by alternately supplying a deposition gas as a precursor gas and a reactive gas to a substrate. Since a thin film obtained by such ALD can be produced with a very thin film thickness of about 0.1 nm, it is effectively used for various devices as a highly accurate film formation.

For example, a film forming apparatus capable of improving the maximum degree of freedom of film formation while suppressing the manufacturing cost is known (Patent Document 1).
The film forming apparatus includes a plurality of roll members, a transport mechanism for transporting a base material as a film forming body, and a roll of a precursor gas for performing atomic layer deposition that is disposed opposite to the roll member. And a plurality of head portions as gas sources capable of outputting locally. And each head part is comprised so that a multiple types of precursor gas can be output separately.

  Further, a film forming method for forming a thin film on a substrate using a material in a gas phase state while transporting the substrate continuously or intermittently, the step of arranging the substrate around a rotating drum, Rotating the rotating drum at a first speed, supplying each of at least two materials to the rotating drum, and transporting the substrate at a second speed, the first speed and the second A film forming method characterized by a difference in speed is also known (Patent Document 2).

JP 2011-137208 A JP 2012-193438 A

In these film forming apparatuses or film forming methods, a flexible film or sheet is used as a substrate, and different gases are generated by passing through a plurality of film forming heads while the substrate is being transported. Alternately supplied to the substrate.
In the film forming apparatus and the film forming method, different gases are alternately supplied to the substrate so that the supplied gas reacts with the layer of the film forming component formed on the substrate among the already supplied gases. Although a thin film of atomic layer units is formed, since this reaction depends on temperature, it is necessary to increase the temperature of the substrate in order to enhance the reaction. For this reason, when using a flexible and resin-based film as a substrate, the type of the substrate is easily limited, and the temperature of the substrate is also easily limited.

On the other hand, ALD (plasma ALD) using plasma which is not easily limited by the temperature of the substrate is also known.
However, a plasma ALD film forming apparatus that forms a film on a substrate to be transported uses radicals (radical atoms or radical molecules) generated from plasma and having high reaction activity. It is not preferable to mix in a gas phase with another film forming gas that reacts.
In addition, there is currently no known plasma ALD film forming apparatus for forming a film on a substrate to be transferred, which can efficiently form a film and can realize ALD with a simple structure.
On the other hand, as a plasma ALD film forming apparatus for forming a stationary substrate in a film forming container, a configuration using parallel plate electrodes is known. When this configuration is applied to the substrate being transported, it is difficult to efficiently generate plasma over the entire space between the parallel plate electrodes in order to radicalize the reactive gas, and radicals are efficiently supplied onto the substrate. That was difficult.

  Therefore, the present invention provides a film forming apparatus for forming a substrate being transferred using plasma ALD, which can efficiently supply radicals onto the substrate, and a film forming apparatus using this film forming apparatus. An object is to provide a membrane method.

One embodiment of the present invention is a film formation apparatus that forms a thin film in units of atomic layers using a film formation gas and a reactive gas. The film forming apparatus
A deposition container;
A transport mechanism for transporting a film forming substrate in the film forming container;
A plurality of plate-like electrode plates provided along a transport path of the substrate in the film-forming container, each main surface of the electrode plate being provided so as to face the surface of the substrate; A plasma generating electrode plate that generates plasma using a reactive gas in the film formation space by forming a magnetic field by flowing a current in a direction crossing the substrate transport path in each;
A plurality of injectors provided along the transport path with a gap so that radicals generated from the plasma are supplied to the substrate between the plasma generating electrode plate and the transport path; And an injector for supplying the film-forming gas toward the substrate.
A transverse portion where the current flows through each of the plasma generating electrode plates to form a magnetic field is provided at the same position as the gap between the injectors with respect to the position along the transport direction.

  The plasma generating electrode plate has a power supply end that receives power supply and a grounded end that is grounded, and a current flows in a direction crossing the transport path of the substrate to form a magnetic field from the power supply end of the transverse portion. The direction of the current path toward the ground end is preferably opposite to each other in the crossing portions adjacent to each other in the transport direction among the crossing portions.

  The power supply end and the grounding end are alternately provided along the transport direction at the end of the plasma generation electrode plate located on at least one of both sides of the transport path. Is preferable.

  The plasma generation electrode plate is configured using a linear plate material, and the power feeding end and the grounding end are located on different sides across the transport path, and the power feed end on both sides sandwiching the transport path. It is preferable that the grounding end is provided alternately along the transport direction.

  The plasma generating electrode plate is configured by using a U-shaped plate material in which two transverse portions extend in a direction crossing the transport path and are disposed so as to sandwich one of the injectors with respect to a position in the transport direction. It is also preferable that the power feeding end and the grounding end are located on the same side across the transport path.

  It is preferable that the power supply ends of the plasma generation electrode plate receive AC power supply having the same phase.

  As one form of such a film forming apparatus, the transport mechanism includes a pair of rotating rollers, and the substrate is a long flexible film. In this case, it is preferable that the film is wound on the other of the rotating rollers from a state wound on one of the rotating rollers.

Furthermore, another embodiment of the present invention is a film formation method performed using the above film formation apparatus. The substrate used in the film forming method is a film wound around a roll. The film formation method is as follows:
A first step of drawing the film from the roll and transporting the film for film formation, and then winding the film formed during transport to form a film-forming treatment roll;
In order to increase the film thickness of the film, a second step of drawing out the film again from the film forming roll and transporting the film, winding the film formed during the transfer into a new film forming roll, By repeating the second step, the film thickness of the formed film is set to the target thickness.

  According to the film forming apparatus and the film forming method described above, radicals can be efficiently supplied onto the substrate being transported.

It is a schematic block diagram of the film-forming apparatus of this embodiment. (A) is a schematic perspective view of the injector used for this embodiment, (b) is a figure explaining the board | substrate opposing surface of the injector of this embodiment. (A), (b) is a figure explaining arrangement | positioning of the plasma production electrode plate of this embodiment. It is a figure explaining the plasma production electrode plate used for the modification 1. FIG. It is a figure explaining the plasma production electrode plate used for the modification 2.

  Hereinafter, the film forming apparatus of the present invention will be described in detail.

(Deposition system)
FIG. 1 is a schematic configuration diagram of a film forming apparatus of the present embodiment. The film forming apparatus 10 includes a film forming container 12, a transport mechanism 14, a plasma generation unit 16, an injector unit 18, a gas supply unit 20, and an exhaust unit 22. The film forming apparatus 10 is a method for generating plasma by a magnetic field generated by a current flowing through a plasma generating electrode plate. This method is different from a method in which plasma is generated by a high voltage generated by resonance of an antenna element such as a monopole antenna or a capacitively coupled plasma method (CCP) in which a voltage is generated between parallel plate electrodes to generate plasma. It is.
In the present embodiment, a description will be given of a flexible substrate that is an extremely thin glass plate or resin film and can be wound in a roll shape as the substrate for film formation. However, the deposition substrate used in the present invention is not limited to a flexible substrate. For example, a single plate-like hard substrate can be used as the deposition substrate.

  In the film forming space of the film forming container 12, a transport mechanism 14, a plasma generating electrode plate 16a belonging to the plasma generating unit 16, and an injector 18a belonging to the injector unit are mainly provided. The film formation container 12 is a container for maintaining the film formation space in the film formation container 12 at a predetermined pressure or depressurizing the film formation substrate in the film formation space. Each of the outer peripheral wall surfaces of the film forming container 12 is provided with a heater 24 in order to set the atmosphere in the film forming space to a temperature suitable for the film forming process.

  The film forming substrate transported by the transport mechanism 14 is a flexible film F wound around rolls (rotating rollers 14a and 14b). The transport mechanism 14 includes rotating rollers 14a and 14b. The rotation rollers 14a and 14b are connected to a drive motor (not shown), and the rotation rollers 14a and 14b are configured to rotate by the rotation of the drive motor. The direction of rotation of the drive motor can be selected. A film F is wound around the rotating rollers 14a and 14b, and the film F has a roll shape. When forming the film, the transport mechanism 14 rotates one of the rotating rollers 14a and 14b as a take-up roller and the other as a feed roller. That is, the rotation of the rotating rollers 14a and 14b draws the film F from the state wound around the roll (rotating roller 14b), and the rotating roller 14a winds up. At this time, the drawn film F is conveyed in one direction for film formation, and then the film F formed during conveyance is wound up by the rotating roller 14a to form a film forming process roll. FIG. 1 illustrates that the film F is conveyed from the rotating roller 14b to the rotating roller 14a and wound up by the rotating roller 14a.

  In this embodiment, in order to increase the thickness of the thin film formed on the film F, it is preferable to repeatedly form the film on the film F. At this time, the transport mechanism 14 pulls out again the film-forming treatment roll obtained by winding the film F after film formation with the rotating roller 14a, toward the rotating roller 14b from the rotating roller 14a, that is, the previous film forming roll. It is preferable to transport in the direction opposite to the transport direction in the film. During conveyance, the film F is formed and the film thickness is increased. The rotating roller 14b winds up the film F formed into a new film forming roll. Thereafter, in order to further increase the film thickness, the film F is conveyed from the rotating roller 14b toward the rotating roller 14a, that is, in the direction opposite to the conveying direction during the previous film formation. During conveyance, the film F is formed and the film thickness is increased. The rotating roller 14a winds up the film F formed into a new film forming roll. As described above, it is preferable that the thickness of the thin film formed on the film F is set to a target thickness by increasing the thickness of the thin film while repeating conveyance of the film F in different directions. That is, it is preferable that the rotation rollers 14a and 14b can rotate in different directions, and the transport direction of the film F is freely selected in two different directions.

  The exhaust unit 22 includes exhaust devices 22a and 22b such as a rotary pump or a dry pump. The exhaust unit 22 exhausts the gas in the film formation space in the film formation container 12 and the plasma generation space in which plasma is generated, and maintains a constant pressure, for example, a reduced pressure state of 1 to 100 Pa. The exhaust device 22a exhausts reactive gas in a plasma generation space described later. The exhaust device 22b exhausts the gas in the film formation space including the plasma generation space below the plasma generation electrode plate 16a.

  The plasma generation unit 16 includes a plasma generation electrode plate 16a, a matching box 16c, and a high frequency power source 16d. The plasma generation unit 16 is a unit that generates a reactive substance that reacts with the film forming component adsorbed on the film F of the film forming gas. A space partition wall 17 is provided in the film forming container 12 so as to cross the cross section of the film forming container 12.

  A plurality of plasma generation electrode plates 16a in the film formation container 12 are provided along the transport path of the film F in the film formation container. The main surface of each plasma generating electrode plate 16a is provided to face the surface of the film F. In each plasma generation electrode plate 16a, a current flows in a direction crossing the film F conveyance path to form a magnetic field, thereby generating plasma using a reactive gas in the deposition space. For this reason, each of the plasma generation electrode plates 16a is connected to the high frequency power supply 16d from the ceiling surface of the film forming container 12 via the matching box 16c by a power supply line. The high frequency power supply 16d supplies a high frequency voltage of 13.56 MHz, for example, to the plasma generation electrode plate 16a. A power supply line for supplying high frequency power to the high frequency power supply 16a extends from the matching box 16c outside the film formation container 12 into the film formation container 12 through a hole provided in the ceiling surface of the film formation container 12, and the power supply line is a plasma. Connected to each of the generation electrode plates 16a. At this time, the hole is sealed with the insulator 16e.

  Specifically, a current, for example, a current of several amperes, flows through each of the plasma generating electrode plates 16a along the longitudinal direction of the plate material (the direction crossing the transport path). A current flows through each of the plasma generation electrode plates 16a to generate a magnetic field in the film formation space. Unlike the conventional antenna element that resonates the antenna element to generate a high voltage in the space in the vicinity of the antenna element, the plasma generating electrode plate 16a does not need to generate resonance and is generated. Plasma is generated by a magnetic field. For this reason, it is not necessary to adjust the frequency so as to correspond to the resonance of the plasma generating electrode plate 16a. Further, unlike the capacitively coupled plasma generation method, it is not necessary to use one large parallel plate electrode that covers the entire transfer path, and the plasma generation electrode plate 16a may be disposed only in a portion where plasma is to be generated. Therefore, the electrode plate can be miniaturized and a compact film forming apparatus can be configured. Further, since the surface of the plasma generating electrode plate 16a does not require a large area like the surface of the conventional parallel plate electrode, power consumption can be suppressed, and plasma generated per unit power and further generated from the plasma. A good quality film can be formed on the film F by increasing the amount of radicals (radical atoms or radical molecules).

The film formation container 12 is provided with an insulator plate 16f extending from the side wall, and the plasma generation electrode plate 16a and the insulation plate 16f separate the space in the film formation container 12 into an upper space and a lower space. The air pressure in the lower space is controlled by the exhaust unit 22 to be in a reduced pressure state. Accordingly, when a current flows through the plasma generation electrode plate 16a, plasma is generated using a reactive gas in the space below the plasma generation electrode plate 16a. More specifically, a plasma generation space for generating plasma is formed between the wall formed by the plasma generation electrode plate 16 a and the insulating plate 16 f and the space partition wall 17.
A film-like dielectric 16g is provided on the side of the plasma generation electrode plate 16a facing the plasma generation space. For example, quartz is used for the dielectric 16g. The reason why the dielectric 16g is provided is to prevent the plasma generation electrode plate 16a from being corroded by the plasma and to efficiently propagate the electric energy to the plasma.
The arrangement of the plasma generating electrode plate 16a will be described later.

  A gas supply hole is provided on the side wall (the right side wall in FIG. 1) of the film forming container 12 that defines the plasma generation space. As shown in FIG. 1, the gas supply hole is connected to a gas supply pipe connected to a reactive gas source 20a described later. A reactive gas is supplied into the plasma generation space through the gas supply hole. That is, the reactive gas is supplied from the side wall of the film forming container 12 into the plasma generation space. Further, a gas exhaust hole is provided in the side wall (left side wall in FIG. 1) of the film forming container 12 that defines the plasma generation space. As shown in FIG. 1, the gas exhaust hole is connected to an exhaust pipe connected to the exhaust device 22a.

The space partition wall 17 is composed of a plate-like insulating member.
An injector unit 18 is provided below the space partition wall 17 and above the transport path of the film F, that is, between the plasma generation electrode plate 16a and the transport path. The injector unit 18 includes a plurality of injectors 18 a along the film F conveyance path. Each of the injectors 18a is provided in a line along the transport path of the film F with a gap so that radical atoms or radical molecules generated from the plasma in the plasma generation space are supplied to the film F. Yes. Each of the injectors 18 a has a film forming gas injection port extending in a direction orthogonal to the transport direction of the film F, and supplies the film forming gas toward the film F. By supplying the film forming gas toward the film F, a layer of a film forming component that is at least a part of the film forming gas is formed on the film F. The film forming component is chemically adsorbed on the film F. That is, as the film forming gas, a gas is selected such that the film forming components are chemically adsorbed on the film F.

  The space partition wall 17 has a slit extending in a direction perpendicular to the film F conveyance direction at a position in the film F conveyance direction corresponding to a gap between the adjacent injectors 18 a along the film F conveyance path. Shaped through holes are provided. Thereby, when the layer of the film-forming component adsorbed on the film F passes through the gap between the injectors immediately after that, the reactive atom radical atom or radical molecule obtained from the plasma generated in the plasma generation space described above. Is lowered toward the film F through the through hole and the gap. That is, the film forming apparatus 10 is configured such that radical atoms or radical molecules are supplied to the layer of the film forming component formed on the film F from the through holes located between the adjacent injectors 18a and the gaps. The configuration of the injector 18a will be described later.

Dummy injectors 18b are provided on both sides of the row of the plurality of injectors 18a. The dummy injector 18b does not have a function of supplying a film forming gas. The dummy injector 18b is provided to form a gap similar to the gap formed between the two injectors 18a between the adjacent injector 18a and supply radical atoms and radical molecules to the film F from the gap. ing.
As described above, the dummy injector 18b that does not supply the film-forming gas toward the film F has a gap further downstream in the transport direction than the most downstream injector located on the most downstream side in the transport direction of the film F. Is provided. More specifically, the dummy injector 18b, together with the most downstream injector located on the most downstream side, is the most downstream through hole located on the most downstream side in the transport direction among the slit-like through holes 17a provided in the space partition wall 17. It is preferable that it is provided so as to sandwich it. At this time, when the rotating rollers 14a and 14b rotate in the reverse direction to repeatedly carry and transport the film F, the dummy injectors 18b are provided on both sides of the injectors 18b arranged in a line as shown in FIG. It is preferable.

A gas supply hole is provided in the side wall of the film forming container 12 below the space partition wall 17 (the right side wall in FIG. 1). A gas supply pipe connected to a purge gas source 20c described later is connected to the gas supply hole. The purge gas is a gas used for efficiently exhausting unnecessary film forming gas, reactive gas, radical molecules, radical atoms and the like.
Further, each of the injectors 18a is connected to a gas supply pipe connected to a film forming gas source 20b described later and a gas supply pipe connected to an inert gas source 20d.

The gas supply unit 20 includes a reactive gas source 20a, a film forming gas source 20b, a purge gas source 20c, an inert gas source 20d, and mass flow controllers 22e and 22f (see FIG. 2A).
As the reactive gas supplied from the reactive gas source 20a, for example, O ₂ , O ₃ , H ₂ O, N ₂ O, N ₂ , NH ₃ or the like is used. As the film forming gas supplied from the film forming gas source 20b, for example, an organometallic compound gas containing TMA (trimethylaluminum), TEMAZ (tetraethylmethylaminozirconium), TEMAHf (tetraethylmethylaminohafnium), aminosilane, or the like is used. As the purge gas supplied from the purge gas source 20c, an inert gas such as nitrogen gas, argon gas, neon gas, or helium gas is used. As the inert gas supplied by the inert gas source 22d, an inert gas such as nitrogen gas, argon gas, neon gas, or helium gas is used. The inert gas refers to a gas that does not react with the reactive gas and the film forming gas.

(Injector 18a)
FIG. 2A is a schematic perspective view of the injector 18a. FIG. 2A illustrates the substrate facing surface 30 facing the film F so as to face upward. FIG. 2B is a diagram illustrating the substrate facing surface 30 of the injector 18a.

  The injector 18 a is provided on the surface of the space partition wall 17 opposite to the surface facing the plasma generating electrode plate 16 a, and supplies a film forming gas toward the film F. However, the injector 18a not only simply supplies a film forming gas, but also sucks an extra film forming gas that is not adsorbed to the film F, and forms a film in a gap between the injector 18a and the adjacent injector 18a. An inert gas is output as a barrier gas so that the gas does not diffuse.

A plurality of slit-shaped openings 32 are provided in the substrate facing surface 30. The length of the opening 32 is shorter than the width of the film F.
As shown in FIG. 2B, the opening 32 provided in the substrate facing surface 30 includes a film forming gas supply port 50, first gas exhaust ports 52 and 52, and inert gas supply ports 54 and 54. , Second gas exhaust ports 56, 56.
The film forming gas supply port 50 is an opening for outputting a film forming gas. The first gas exhaust ports 52, 52 are openings that are provided on both sides of the film F transport direction with respect to the film forming gas supply port 50 and suck excess gas on the film F. The inert gas supply ports 54 and 54 are provided on the side away from the film formation gas supply port 50 in the transport direction of the film F with respect to the first gas exhaust ports 52 and 52, respectively, and with respect to the film formation components. Supply inert gas.

  On the opening surfaces of the film forming gas supply port 50 and the inert gas supply ports 56, 56, members 50 a, 54 a that block a part of the openings are provided along the longitudinal direction of the slit-shaped opening. The members 50a and 54a are provided on the surface of the film F by suppressing the film forming gas supply ports 50 and the inert gas supply ports 54 and 54 from the injection speed of the inert gas as much as possible. This is because the film forming gas and the inert gas are gently supplied. The width W (see FIG. 2B) of the injection tie 18a is, for example, 20 to 40 mm, and the film forming gas supply port 50, the first gas exhaust ports 52 and 52, the inert gas supply ports 54 and 54, and The opening width of each of the second gas exhaust ports 56, 56 is, for example, 1 to 3 mm.

In order to supply and exhaust such gas, the substrate facing surface 30 is provided with gas supply ports 34 and 36 and gas exhaust ports 38 and 40 having an elliptical opening in addition to the opening 32.
The gas supply port 34 is connected to an inert gas supply pipe 42 as shown in FIG. The inert gas supply pipe 42 is connected to the inert gas source 20d through the mass flow controller 22f. The mass flow controller 22f controls the supply amount of the inert gas into the film formation space.
As shown in FIG. 2A, the gas supply port 36 is connected to a film forming gas supply pipe 44. The film forming gas supply pipe 44 is connected to the film forming gas source 20b via the mass flow controller 22e. The mass flow controller 22e controls the supply amount of the film forming gas into the film forming space.
As shown in FIG. 2A, exhaust pipes 46 and 48 are connected to the gas exhaust ports 38 and 40, respectively. The exhaust pipes 46 and 48 are connected to the exhaust device 22b.
In the present embodiment, the gas supply ports 34 and 36 and the gas exhaust ports 38 and 40 are provided on the substrate facing surface 30 of the injector 18a, but are not limited thereto. The gas supply ports 34 and 36 and the gas exhaust ports 38 and 40 may be provided on the other surface of the injector 18a.

  In the present embodiment, the second gas exhaust ports 54 are provided, but they are not necessarily provided. However, the inert gas is surely exhausted, and the inert gas flows into the gap between the adjacent injectors 18a, so that supply of radical atoms and radical molecules necessary for film formation to the film F is not hindered. The second gas exhaust ports 54 are preferably provided.

(Plasma generating electrode plate 16a)
3A and 3B are views for explaining the arrangement of the plasma generating electrode plate 16a.
The plasma generating electrode plate 16a is configured using a linear plate material.
The crossing portion where the current of each plasma generating electrode plate 16a flows in the direction crossing the transport path to form a magnetic field is provided at the same position as the gap 18c between the injectors 18a with respect to the position along the transport direction of the film F. Yes. Thus, by arranging the plasma generation electrode plate 16a, the plasma P is generated in the plasma generation space below each of the plasma generation electrode plates 16a, and radical molecules or radical atoms generated from the plasma P or plasma P are generated. Since it moves to the gap 18c, radical molecules or radical atoms can be efficiently supplied to the film F. In addition, since the width of the plasma generation electrode 16a (the length along the transport direction) may be a width that substantially corresponds to the length along the transport direction of the gap 18c, plasma using a conventional parallel plate electrode may be used. Since a narrower electrode plate can be used as compared with the case of generation, it becomes a compact device and power consumption can be suppressed. As a result, the amount of plasma per unit power, and further the amount of radical atoms or radical molecules generated from the plasma can be increased, and radicals can be efficiently supplied onto the substrate, thereby forming a good film on the film F. be able to.
The wiring length is adjusted so that the power supply ends of the plasma generating electrode plate 16a receive AC power supply in the same phase. The power supply ends of the plasma generating electrode plate 16a are supplied with AC power having the same phase, whereby a magnetic field having the same phase can be generated and the plasma P can be formed efficiently.

  The plasma generating electrode plate 16a has a power feeding end 16h that receives power feeding and a grounding end 16i that is grounded. The direction of the current path from the feeding end 16h to the grounding end i of the transverse portion where the current flows in the direction transverse to the conveyance path of the film F and forms the magnetic field is between two transverse portions adjacent to the conveyance direction, They are opposite to each other. In this way, in the plasma generation method using a magnetic field as in this embodiment, the electron density of the plasma generated in the plasma generation space is high on the ground end 16i side, The electron density is low on the end 16h side. Although the reason for this is not clear, the plasma generated based on the magnetic field generated by the current (plasma derived from the current) is dominant on the ground end 16i side, whereas the power supply end 16h side is dominant. Then, it is thought that it originates in the plasma (plasma derived from a voltage) produced | generated by a high voltage being dominant. On the high voltage feeding end 18h side, electrons are heated by the electric field, so that sufficient energy cannot be received, and it is considered that high-density plasma is difficult to be generated. For this reason, the density of radical molecules or radical atoms supplied in a direction orthogonal to the transport direction of the film F is different, and the thickness of the formed thin film tends to be non-uniform. Therefore, by disposing the feeding end 16h and the grounding end 16i in opposite directions between the adjacent plasma generation electrodes 16a, that is, the current paths from the feeding end 16h to the grounding end i are opposite to each other. By doing so, the thickness of the formed thin film can be made uniform. As described above, in the plasma generation electrode plate 16a, the power feeding end 16h and the grounding end 16i are located on different sides across the transport path of the film F, and the power feeding end 16h and the grounding end 16i are located on both sides across the transportation path. They are provided alternately along the transport direction.

(Film formation method)
In such a film forming apparatus 10, the injectors 18a are provided with a plurality of gaps, and the film F being conveyed receives supply of the film forming gas from the injectors 18a each time it passes through each injector 18a. The film forming component of the film forming gas is chemically adsorbed on the film F in atomic layer units.
On the other hand, when the film F is transported, reactive gas is supplied to the plasma generation space, and plasma using the reaction product gas is generated by the magnetic field generated by the plasma generation electrode plate 16a through which current flows. The plasma or radical atoms or radical molecules generated from the plasma reaches the film F by passing through the through holes of the space partition wall 17 and the gap 18c between the injectors 18a. At this time, a part of the plasma is in the state of radical atoms or radical molecules due to neutralization of ions. Therefore, the thin film is formed by the reaction of the film-forming components in units of atomic layers adsorbed on the film F by the supply of the film-forming gas from the injector 18a and the radical molecules or radical atoms. Since a plurality of gaps 18c between the injectors 18a and the injectors 18a are provided alternately, the thin film formed on the film F gradually becomes thicker during the conveyance of the film F.

In this way, after the film F is pulled out from the roll and transported to form the film F, the film F formed during transport is wound to form a film forming roll (first step). Further, in order to increase the film thickness of the film F, the film F is pulled out again from the film formation processing roll and conveyed, and the film F formed during the conveyance is wound up to form a new film formation processing roll (second). Step). Then, by repeating the second step, the film thickness can be set to the target thickness.
In this way, the film forming apparatus 10 can form a thin film on the film F.

(Modification 1)
FIG. 4 is a diagram for explaining the shape of the plasma generation electrode plate 16a and the arrangement of the plasma generation electrode plate 16a and the injector 18a according to the first modification.
The plasma generating electrode plate 16a in the first modification is configured by a U-shaped electrode plate.
In the plasma generation electrode plate 16a, two opposing U-shaped straight portions are transverse portions extending in a direction crossing the transport path. And the said crossing part of the plasma generation electrode 16a is arrange | positioned so that one of the injectors 18a may be pinched | interposed regarding the position of the conveyance direction of the film F. FIG. As described above, since the plasma generation electrode plate 16a has a U shape, the directions of the current paths from the power supply end 16h to the ground end 16i are opposite to each other at two transverse portions of one plasma generation electrode 16a. For this reason, as described above, the electron density is high on the ground end 16i side and the electron density is low on the power supply end 16h side. The thickness of the thin film to be formed can be made uniform in the width direction of the film F.
Further, the plasma electrode plate 16a is arranged so that the power supply end 16h connected to the high-frequency power source 16d and the ground end 16i grounded are located on the same side across the transport path. Adjacent plasma generation electrode plates 16a also have a U-shape, and the power supply end 16h and the ground end 16i that is grounded are arranged on the same side across the transport path. In the plasma generating electrode plate 16a having the feeding end 16h and the grounding end 16i, the direction of the current path from the feeding end 16h to the grounding end 16i of the transverse portion is set between the transverse portions adjacent to each other in the transport direction among the transverse portions. In opposite directions. By arranging the feeding end 16h and the grounding end 16i in the opposite directions between the adjacent plasma generation electrodes 16a, the electron density on the grounding end 16i side is the same as that of the present embodiment shown in FIG. The problem of non-uniformity in the width direction of the film F due to the high thickness of the film F resulting from the low electron density on the power supply end 16h side can be solved. It can be made uniform in the width direction of F.

(Modification 2)
FIG. 5 is a diagram for explaining the shape of the plasma generation electrode plate 16a and the arrangement of the plasma generation electrode plate 16a and the injector 18a in the second modification.
The plasma generation electrode plate 16a in the second modification is configured by a U-shaped electrode plate, as in the first modification. The plasma generating electrode plate 16a is a transverse portion in which two U-shaped opposing linear portions extend in a direction crossing the transport path. And the said crossing part of the plasma generation electrode 16a is arrange | positioned so that one of the injectors 18a may be pinched | interposed regarding the position of the conveyance direction of the film F. FIG. The plasma electrode plate 16a is arranged so that the power supply end 16h connected to the high frequency power supply 16d and the ground end 16i grounded are located on the same side across the transport path. However, the directions of the adjacent plasma generation electrodes 16a, specifically, the U-shaped directions are opposite to each other. In FIG. 5, the directions of the U-shaped plasma generation electrode 16a are the lower side, the upper side, and the lower side.
On the other hand, the direction of the current path from the feeding end 16h to the grounding end 16i in the transverse portion is opposite to the feeding end 16h so that the transverse portions adjacent to each other in the transport direction among the transverse portions are opposite to each other. A grounding end 16i is defined. Similar to the present embodiment shown in FIG. 3A, the thickness of the formed thin film can be made uniform in the width direction of the film F. Further, since the plasma generation electrode plate 16a has a U-shape, the directions of the current paths from the power supply end 16h to the ground end 16i are opposite to each other at two transverse portions of one plasma generation electrode 16a. For this reason, as described above, the electron density is high on the ground end 16i side and the electron density is low on the power supply end 16h side. The thickness of the thin film to be formed can be made uniform in the width direction of the film F.

  As described above, in the present embodiment, the first modification, and the second modification, the transverse portion where the current of each plasma generation electrode plate 16a flows to form a magnetic field is the gap between the injectors 18a with respect to the position along the film F conveyance direction. It is provided at the same position as 18c. Plasma P is generated in the plasma generation space below each of the plasma generation electrode plates 16a. Since the radical molecules or radical atoms generated from the plasma P or the plasma P move to the gap 18c, the radical molecules or radical atoms can be efficiently supplied to the film F, and the film formation can be efficiently performed. In addition, since the width of the plasma generation electrode 16a (the length along the transport direction) may be a width that substantially corresponds to the length along the transport direction of the gap 18c, plasma using a conventional parallel plate electrode may be used. A narrower electrode plate can be used than in the case of generation. Therefore, the film forming apparatus 10 has a compact apparatus configuration, and power consumption is also suppressed. Furthermore, since the amount of radical atoms or radical molecules per unit power can be increased, radicals can be efficiently supplied onto the substrate, the reaction during film formation can be performed well, and a high-quality film can be obtained. Can be formed on the film F.

  The plasma generation electrode plate 16a in the present embodiment, the first modification, and the second modification has a power feeding end 16h and a grounding end 16i, and a crossing in which a current flows in a direction crossing the transport path of the film F to form a magnetic field. The direction of the current path from the feeding end 18h of the portion toward the grounding end 18i is opposite to each other in the transverse portions adjacent to each other in the transport direction among the transverse portions. For this reason, the thickness of the thin film formed can be made uniform in the width direction of the film F.

As shown in FIG. 3, the plasma generating electrode plate 16a of the present embodiment is configured using a linear plate material, and the power supply end 16h and the ground end 16i are located on different sides with the conveyance path interposed therebetween. The power supply end 16h and the grounding end 16i are alternately provided along the transport direction on both sides of the transport path. For this reason, it is easy to wire the power supply line and the ground line.
Further, as shown in FIG. 4, the plasma generating electrode plate 16a is U-shaped so that two transverse portions extend in a direction crossing the transport path and sandwich one of the injectors 18a with respect to the position in the transport direction. It is comprised using a plate-shaped board | plate material. For this reason, the thickness of the thin film formed on the film F can be made uniform in the width direction of the film F. Further, since the power feeding end 16h and the grounding end 16i are located on the same side with the conveyance path interposed therebetween, it is easy to wire the power feeding line and the grounding line.

  In this embodiment and Modifications 1 and 2, the transport mechanism includes rotating rollers 14a and 14b, and the substrate on which the thin film is formed is a long flexible film F. The film F is wound around the other of the rotating rollers 14a and 14b from the state wound around one of the rotating rollers 14a and 14b. For this reason, when the rotation rollers 14a and 14b wind the film F in one film formation container 12, the rotation direction is sequentially changed to the first rotation direction and the second rotation direction opposite to the first rotation direction. Thus, the film F can be repeatedly reciprocated along the injector unit 18, and film formation can be performed during conveyance. Therefore, the film thickness of the thin film formed on the film F can be efficiently made to the target thickness.

  Although the film forming apparatus and the film forming method of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments and examples, and various improvements and modifications can be made without departing from the gist of the present invention. Of course it is also good.

DESCRIPTION OF SYMBOLS 10 Film-forming apparatus 12 Film-forming container 14 Transport mechanism 14a, 14b Rotating roller 16 Plasma generating unit 16a Plasma generating electrode plate 16c Matching box 16d High frequency power supply 16e Insulator 16f Insulator plate 16g Dielectric 16h Feeding end 16i Grounding end 17 Space partition Wall 18 Injector unit 18a Injector 18b Dummy injector 18c Clearance 20 Gas supply unit 20a Reactive gas source 20b Deposition gas source 20c Purge gas source 20d Inert gas source 22 Exhaust unit 22a, 22b Exhaust unit 24 Heater 30 Substrate facing surface 32 Opening 34, 36 Gas supply port 38, 40 Gas exhaust port 42 Inert gas supply pipe 44 Deposition gas supply pipe 46, 48 Exhaust pipe 50 Film formation gas supply ports 50a, 54a Member 52 First gas exhaust port 54 Active gas Supply port 56 Second gas exhaust port

Claims (8)

A film forming apparatus for forming a thin film in units of atomic layers using a film forming gas and a reactive gas,
A deposition container;
A transport mechanism for transporting a film forming substrate in the film forming container;
A plurality of plate-like electrode plates provided along a transport path of the substrate in the film-forming container, each main surface of the electrode plate being provided so as to face the surface of the substrate; A plasma generating electrode plate that generates plasma using a reactive gas in the film formation space by forming a magnetic field by flowing a current in a direction crossing the substrate transport path in each;
A plurality of injectors provided along the transport path with a gap so that radicals generated from the plasma are supplied to the substrate between the plasma generating electrode plate and the transport path; An injector for forming a film forming gas and supplying the film forming gas toward the substrate;
A transverse portion where the current flows through each of the plasma generating electrode plates to form a magnetic field is provided at the same position as the gap between the injectors with respect to the position along the transport direction. Membrane device.   The plasma generating electrode plate has a power supply end that receives power supply and a grounded end that is grounded, and a current flows in a direction crossing the transport path of the substrate to form a magnetic field from the power supply end of the transverse portion. The film forming apparatus according to claim 1, wherein the direction of the current path toward the ground end is opposite to each other in the crossing portions adjacent to each other in the transport direction among the crossing portions.   The power supply end and the grounding end are alternately provided along the transport direction at the end of the plasma generation electrode plate located on at least one of both sides of the transport path. The film forming apparatus according to claim 2. The plasma generating electrode plate is configured using a linear plate material, and the power feeding end and the grounding end are located on different sides across the transport path,
4. The film forming apparatus according to claim 2, wherein the power supply end and the ground end are alternately provided along the transport direction on both sides of the transport path. 5.   The plasma generating electrode plate is configured by using a U-shaped plate material in which two transverse portions extend in a direction crossing the transport path and are disposed so as to sandwich one of the injectors with respect to a position in the transport direction. The film forming apparatus according to claim 2, wherein the power feeding end and the grounding end are located on the same side across the transport path.   The film forming apparatus according to claim 2, wherein the power supply terminals of the plasma generation electrode plate receive AC power supply in the same phase. The transport mechanism includes a pair of rotating rollers,
The substrate is a long flexible film,
The film forming apparatus according to claim 1, wherein the film is wound on the other of the rotating rollers from a state wound on one of the rotating rollers. A film forming method performed using the film forming apparatus according to claim 1,
The substrate is a film wound on a roll,
A first step of drawing the film from the roll and transporting the film for film formation, and then winding the film formed during transport to form a film-forming treatment roll;
In order to increase the film thickness of the film, a second step of drawing out the film again from the film forming roll and transporting the film, winding the film formed during the transfer into a new film forming roll, Including
A film forming method, wherein the film thickness of the formed film is set to a target thickness by repeating the second step.

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