JP2017218611A - Film deposition apparatus, and film deposition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film deposition apparatus and a film deposition method capable of downsizing the whole device, reducing power consumption, and enhancing productivity.SOLUTION: A film deposition apparatus 1 is equipped with a film deposition chamber 10 having at least a first zone 11, a second zone 12, a third zone 13, and a first electrode 42 and a second electrode 43 arranged in the second zone 12 for plasma activation. The first electrode 42 is connected to a first plasma activation mechanism. The discharge face of the first electrode 42 faces to the film deposition face of a flexible substrate 50 when the flexible substrate 50 passes the second zone 12 in the first direction of travel. The second electrode 43 is connected to a second plasma activation mechanism. The discharge face of the second electrode 43 faces to the film deposition face of the flexible substrate 50 when the flexible substrate 50 passes the second zone 12 in the second direction of travel. The first plasma activation mechanism and the second plasma activation mechanism are each independently controlled.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a film forming apparatus and a film forming method for forming a thin film on a flexible substrate. More specifically, the present invention is a film forming apparatus for forming a thin film on a flexible base material while intermittently or continuously transporting the flexible base material, and uses deposition (deposition) by a gas phase. More particularly, the present invention relates to a film forming apparatus and a film forming method using an atomic layer deposition method.

  Atomic Layer Deposition (ALD) uses alternating active and reactive gases called precursors (also called precursors), followed by the adsorption of these gases on the substrate surface This is a film forming method in which a thin film (atomic layer) is formed layer by layer at the atomic level by a chemical reaction.

  Specifically, in the surface adsorption, when the substrate surface is covered with a certain type of gas, the substrate surface uses a self-limiting effect that does not cause any further adsorption of the gas. When one layer is adsorbed, the unreacted precursor is exhausted. Subsequently, a reactive gas is introduced to oxidize or reduce the precursor, form a thin film having a desired composition, and then the reactive gas is exhausted. By setting this as one cycle and repeating this cycle a plurality of times, the thin film is grown one layer at a time. Therefore, in ALD, a thin film grows two-dimensionally. In addition, ALD has fewer film-forming defects as compared with conventional chemical vapor deposition (CVD) as well as conventional vapor deposition and sputtering. . For these reasons, ALD is expected to be applied to various fields.

  In ALD, there is a method of using plasma in order to activate the reaction in the step of decomposing the reactive gas and reacting with the precursor adsorbed on the substrate. This method is called Plasma Activated ALD (PEALD: Plasma Enhanced ALD), or simply Plasma ALD.

  As a film forming method for the flexible base material, there is a web coating method by a so-called roll-to-roll method in which the flexible base material is unwound from a roll, the film is formed while being conveyed, and the flexible base material is wound on another roll. The web coating method includes not only flexible substrates but also a flexible film that allows continuous conveyance of the substrate to be deposited, or a method in which a portion of the substrate is placed on a flexible tray and conveyed continuously. It is.

  A problem related to ALD includes the use of a special material and its cost. Among these, the biggest problem is that ALD is a method of forming a thin film layer by layer at the atomic level in one cycle. Therefore, film formation is about 5 to 10 times more than film formation methods such as vapor deposition and sputtering. The speed is slow.

  In order to solve such a problem, rather than the conventional method of repeating the supply and exhaust of the precursor in one film forming chamber (this is called a time division type), the film forming chamber is divided into several zones, There has been proposed a film forming method (referred to as a space division type) in which a single precursor or purge gas is supplied to each zone, and a substrate moves back and forth between the zones (for example, Patent Document 1). reference). By this space division type ALD film forming method, the film forming speed was improved.

  Further, in film formation on a flexible substrate by a roll-to-roll method, a method of forming a mixed metal oxide film by alternately changing the material every one ALD cycle or several ALD cycles has been proposed (for example, Patent Documents). 2).

International Publication No. 2007/112370 International Publication No. 2014/182543

  The method described in Patent Document 2 can be expected to improve the film formation rate in ALD film formation on a flexible substrate. However, when the precursor adsorbed on the flexible base material is reacted with the reactive gas under plasma, for example, when there are two types of precursors and a single electrode is used, each precursor is changed to the reactive gas. The higher one of the plasma input power sufficient to cause the reaction is adopted. Thereby, a sufficient plasma input power can be secured in the reaction with one precursor, but an excessive plasma input power is obtained in the reaction with the other precursor. Excessive plasma input power not only leads to waste of power but also affects the essence of the film forming process, such as failure to obtain a desired film quality.

There is also a problem of downsizing the film forming apparatus.
FIG. 6 is a schematic cross-sectional view showing a configuration of a film forming chamber constituting a conventional film forming apparatus. In order to reduce the size of the film forming apparatus 100 shown in FIG. 6, the diameters of the rollers 121 and 122 provided in the film forming chamber 110 are reduced, and the distance (interval) between the adjacent rollers 121 and 122 is reduced. There is a need. However, if the distance between the electrode 123 and the substrate 200 is not sufficient, stable discharge cannot be performed from the electrode 123. In addition, the electrode-substrate distance has an optimum value determined according to the desired film quality, and therefore the distance cannot be extremely reduced. On the other hand, since the electrodes 123 need to be cooled, if the two electrodes 123 are installed close to each other back to back (in the width direction of the film formation chamber 110), the width of the entire film formation chamber 110 is increased. As a result, the film forming apparatus 100 is also increased in size. When two electrodes 123 are arranged in the vertical direction (the height direction of the film formation chamber 110), the width of the film formation chamber 110 is reduced, but the film formation apparatus 100 has a large structure in the height direction. It will become.

  The present invention has been made in view of the above problems, and provides a film forming apparatus and a film forming method capable of reducing the size of the entire apparatus, reducing power consumption, and improving productivity.

  In order to solve the above problems, a film formation apparatus according to one embodiment of the present invention includes a first zone into which a first gas containing metal or silicon is introduced and a second zone into which a second gas is introduced. An opening through which the flexible substrate passes through the zone, a third zone into which a third gas containing metal or silicon is introduced, and the first zone, the second zone, and the third zone And moving the flexible substrate in the first traveling direction or the second traveling direction opposite to the first traveling direction, thereby moving the flexible substrate into the first zone, By passing the second zone and the third zone a plurality of times in this order or in the reverse order, a single atomic layer is formed on the film-forming surface of the flexible substrate by an atomic layer deposition method. 1 cycle atomic layer deposition A film formation chamber having at least a film formation conveyance path where a plurality of cycles are performed, and a first electrode and a second electrode for plasma activation arranged in the second zone, The electrode is connected to a first plasma activation mechanism, and a discharge surface of the first electrode is formed on the flexible substrate when the flexible substrate passes through the second zone in the first traveling direction. The second electrode is connected to a second plasma activation mechanism, and the discharge surface of the second electrode is connected to the second zone by the flexible substrate. The first plasma activation mechanism and the second plasma activation mechanism can be independently controlled when they pass in the second traveling direction and are opposed to the film-forming surface of the flexible substrate. It is characterized by that.

  In the film forming apparatus according to one embodiment of the present invention, the first plasma activation mechanism and the second plasma activation mechanism may include a direct current power source as a main power source for plasma generation.

  In the film formation apparatus according to one embodiment of the present invention, the first electrode and the second electrode may be bonded to each other with an insulator interposed therebetween.

  In the film formation apparatus according to one embodiment of the present invention, the insulator includes a coolant for cooling the first electrode and the second electrode, between the first electrode and the second electrode. It may have a structure for sealing.

  A film formation method according to one embodiment of the present invention uses the film formation apparatus according to one embodiment of the present invention, and controls the first plasma activation mechanism and the second plasma activation mechanism independently. Then, a thin film is formed on the main film-forming surface of the flexible substrate.

  According to the present invention, it is possible to provide a film forming apparatus and a film forming method capable of downsizing the entire apparatus, reducing power consumption, and improving productivity.

It is a schematic sectional drawing which shows the structure in the film-forming chamber which comprises the film-forming apparatus which concerns on embodiment of this invention. It is sectional drawing which follows the AA line of FIG. 1, and is a figure which shows the structure of the side view inside a film-forming chamber. It is a perspective view which shows an example of the plasma electrode which comprises the film-forming apparatus which concerns on embodiment of this invention. It is the schematic which shows the other example of the plasma electrode which comprises the film-forming apparatus which concerns on embodiment of this invention, (a) is a top view, (b) is sectional drawing which follows the BB line of (a). is there. It is the schematic which shows the other example of the plasma electrode which comprises the film-forming apparatus which concerns on embodiment of this invention, (a) is a top view, (b) is sectional drawing in alignment with CC line of (a). is there. It is a schematic sectional drawing which shows the structure in the film-forming chamber which comprises the conventional film-forming apparatus.

  Embodiments to which the present invention is applied will be described below in detail with reference to the drawings. Note that the drawings used in the following description are for explaining the configuration of the embodiment of the present invention, and the size, thickness, dimensions, and the like of each part shown in the drawings are different from the dimensional relationship of an actual film forming apparatus. There is a case. In addition, embodiments of the present invention are not limited to the embodiments described below, and modifications such as design changes can be made based on the knowledge of those skilled in the art. The described embodiments are also included in the scope of the embodiments of the present invention.

[Film deposition system]
FIG. 1 is a schematic cross-sectional view showing a configuration of a film forming chamber constituting a film forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along the line AA in FIG. 1, and shows a side view configuration in the film forming chamber. FIG. 3 is a perspective view showing an example of a plasma electrode constituting the film forming apparatus according to the embodiment of the present invention. 4A and 4B are schematic views showing another example of the plasma electrode constituting the film forming apparatus according to the embodiment of the present invention, where FIG. 4A is a plan view, and FIG. 4B is a BB line in FIG. It is sectional drawing which follows. FIG. 5 is a schematic view showing another example of the plasma electrode constituting the film forming apparatus according to the embodiment of the present invention, where (a) is a plan view and (b) is a CC line of (a). It is sectional drawing which follows.
A film forming apparatus 1 shown in FIGS. 1 and 2 is a space division type ALD film forming apparatus that forms a thin film on a flexible substrate 50 by using atomic layer deposition (ALD).
1 and 2 show only the film forming chamber 10. In FIG. 1 and FIG. 2, a mechanism for unwinding and winding up a base material that is usually required as a film forming apparatus is omitted. Also, in FIG. 1 and FIG. 2, configurations that can be easily assumed by those involved in the implementation, such as a vacuum pump and a roller driving device, are omitted. That is, FIGS. 1 and 2 briefly show only the information necessary for explaining and implementing the present invention.

  As shown in FIG. 1, the film forming apparatus 1 according to this embodiment includes five zones (first zone 11, second zone 12, third zone 13, and fourth zone) in the film forming chamber 10. The zone 14 is divided into the fifth zone 15), and a single precursor or purge gas is supplied to each zone, and the flexible substrate 50 is moved between the zones to generate a target deposit. This is a space division type ALD film forming apparatus.

  The film forming chamber 10 includes an upper wall 10a, a lower wall 10b, a side wall (right side of the paper surface in FIG. 1) 10c, and a side wall (left side of the paper surface in FIG. 1) 10d, which are each formed in a rectangular shape, and are surrounded by these walls. A rectangular parallelepiped internal space is formed.

  In the film forming chamber 10, a first gas (first precursor) containing metal or silicon is introduced, a first zone 11 forming a first vacuum chamber, and a second gas are introduced, A second zone 12 forming a second vacuum chamber, and a third zone 13 in which a third gas (second precursor) containing metal or silicon is introduced to form a third vacuum chamber; , A fourth zone 14 into which the purge gas is introduced and forms a fourth vacuum chamber, and a fifth zone 15 into which the purge gas is introduced and forms the fifth vacuum chamber. The third zone 13, the fifth zone 15, the second zone 12, the fourth zone 14, and the first zone 11 are in the height direction of the film forming chamber 10 (FIGS. 1 and 2). (In the vertical direction of the paper surface) in this order from the lower wall 10b side to the upper wall 10a side.

In the film forming chamber 10, partition walls 21 that form surfaces along the XY plane (the surface in the horizontal direction of the paper in FIGS. 1 and 2) at four locations in the Z direction (the vertical direction of the paper in FIGS. 1 and 2). , 22, 23, 24 are provided.
The first partition 21 divides the first zone 11 and the fourth zone 14, separates these zones, and has an opening 21 a through which the flexible substrate 50 passes.
The second partition wall 22 divides the fourth zone 14 and the second zone 12, separates these zones, and has an opening 22 a through which the flexible substrate 50 passes.
The third partition wall 23 divides the second zone 12 and the fifth zone 15, separates these zones, and has an opening 23 a through which the flexible substrate 50 passes.
The fourth partition wall 24 divides the fifth zone 15 and the third zone 13, separates these zones, and has an opening 24 a through which the flexible substrate 50 passes.

  The film forming apparatus 1 includes an unwinding roll (not shown) for unwinding the flexible base material 50 installed in an unwinding chamber (not shown), and a flexible base after film forming installed in the winding chamber (not shown). A take-up roll (not shown) for winding the material 60 and guide rollers 31 and 32 that are installed in the film forming chamber 10 and convey the flexible base material 50 (60) between the take-up roll and the take-up roll. And comprising.

In order to perform atomic layer deposition continuously on the surface (film formation surface) 50 a of the flexible base material 50, the film formation apparatus 1 causes the flexible base material 50 to be attached to the first zone 11, the first zone by the guide rollers 31 and 32. By passing the fourth zone 14, the second zone 12, the fifth zone 15, and the third zone 13 in this order (in the order of the first traveling direction), one atom is formed on the surface 50a of the flexible substrate 50. A layer is deposited. In addition, the film forming apparatus 1 uses the guide rollers 31 and 32 to move the flexible substrate 50 to the third zone 13 in order to continuously deposit the atomic layer on the surface (film forming surface) 50 a of the flexible substrate 50. , The fifth zone 15, the second zone 12, the fourth zone 14, and the first zone 11 are passed in the order (in the order of the second traveling direction), so that the surface 50 a of the flexible substrate 50 is 1 Two atomic layers are deposited.
The film forming apparatus 1 continuously deposits atomic layers on the surface 50a of the flexible substrate 50, and deposits atomic layers on the surface 50a of the flexible substrate 50 with the number of cycles necessary to obtain a desired film thickness. For this reason, the number of times the guide rollers 31 and 32 pass the zone by the guide rollers 31 and 32 is designed so that the number of times the guide rollers 31 and 32 pass the flexible substrate 50 through the above-described zone becomes a predetermined number.

  When the flexible substrate 50 is transported in the film forming chamber 10 in the first traveling direction, the flexible substrate 50 includes the first zone 11, the opening 21 a of the first partition 21, the fourth zone 14, An opening 22 a of the second partition 22, a second zone 12, an opening 23 a of the third partition 23, a fifth zone 15, an opening 24 a of the fourth partition 24, and a third zone 13 are formed. It passes through the film transport path P. When the flexible base material 50 is transported in the film forming chamber 10 in the second traveling direction, the flexible base material 50 includes the third zone 13, the opening 24 a of the fourth partition wall 24, and the fifth zone. 15, from the opening 23a of the third partition wall 23, the second zone 12, the opening 22a of the second partition wall 22, the fourth zone 14, the opening 21a of the first partition wall 21, and the first zone 11. It passes through the film formation conveyance path P.

Into the first zone 11, an introduction port (not shown) for introducing a first gas (first precursor) into the inside, and a first gas (first precursor) from the inside are exhausted. An exhaust port (not shown) is provided. A plurality of these inlets and exhaust ports may be provided in the first zone 11.
The first gas (first precursor) containing metal or silicon introduced into the first zone 11 is appropriately selected according to the target deposition material. For example, when the material (target deposition material) deposited on the flexible substrate 50 is aluminum oxide, trimethylaluminum or the like is used as the first precursor.

The third zone 13 has an inlet (not shown) for introducing a third gas (second precursor) therein, and exhausts the third gas (second precursor) from the inside. An exhaust port (not shown) is provided. A plurality of these inlets and exhaust ports may be provided in the third zone 13.
The third gas (second precursor) containing metal or silicon introduced into the third zone 13 is appropriately selected according to the target deposition material. The second precursor may be the same precursor as the first precursor, or may be a different precursor. When the same precursor as the first precursor is used as the second precursor, the effect of this embodiment is exhibited when using different plasma conditions to be described later for reasons such as obtaining desired film quality. . As the second precursor, for example, titanium tetrachloride (TiCl ₄ ) is used.

The second zone 12 is provided with an introduction port (not shown) for introducing a second gas into the inside thereof and an exhaust port (not shown) for exhausting the second gas from the inside thereof. A plurality of these inlets and exhaust ports may be provided in the second zone 12.
The second gas introduced into the second zone 12 is a reactive gas that reacts with the precursor layer made of the first precursor or the second precursor adsorbed on the surface 50 a of the flexible substrate 50. This reactive gas is appropriately selected according to the target deposition material. For example, when the target deposition material is aluminum oxide, water, ozone, hydrogen peroxide, atomic oxygen, or the like is used as the reactive gas. These reactive gases are activated by the plasma electrode 41 disposed in the second zone 12, and are precursors composed of the first precursor adsorbed on the surface 50 a of the flexible substrate 50 in the first zone 11. It reacts with a layer or a precursor layer made of the second precursor adsorbed on the surface 50 a of the flexible substrate 50 in the third zone 13. As a result, one atomic layer made of the target deposition material is formed on the surface 50 a of the flexible substrate 50.

The fourth zone 14 is provided with an introduction port (not shown) through which purge gas is introduced and an exhaust port (not shown) through which purge gas is exhausted. A plurality of these inlets and exhaust ports may be provided in the fourth zone 14.
The fifth zone 15 is provided with an introduction port (not shown) through which purge gas is introduced and an exhaust port (not shown) through which purge gas is exhausted. A plurality of these inlets and exhaust ports may be provided in the fifth zone 15.
An inert gas is used as the purge gas introduced into the fourth zone 14 and the fifth zone 15. As the inert gas, a gas appropriately selected from helium, argon, nitrogen, carbon dioxide and the like is used.

The first precursor introduced into the first zone 11 and the second precursor introduced into the third zone 13 are passed through an exhaust port provided in each zone by a vacuum pump (not shown). Exhausted. Thereby, the pressure in the first zone 11 is maintained within a predetermined range.
The reactive gas introduced into the second zone 12 is exhausted by a vacuum pump (not shown) through an exhaust port provided in the second zone 12. Thereby, the pressure in the second zone 12 is maintained within a predetermined range.

The purge gas introduced into the fourth zone 14 is exhausted by a vacuum pump (not shown) through an exhaust port provided in the fourth zone 14. As a result, the pressure in the fourth zone 14 is kept higher than the pressure in the first zone 11 and the pressure in the second zone 12. For this reason, the first precursor introduced into the first zone 11 and the reactive gas introduced into the second zone 12 are maintained under conditions that make it difficult to diffuse into the fourth zone 14.
Similarly, the purge gas introduced into the fifth zone 15 is exhausted by a vacuum pump (not shown) through an exhaust port provided in the fifth zone 15. Thereby, the pressure in the fifth zone 15 is kept higher than the pressure in the second zone 12 and the pressure in the third zone 13. For this reason, the second precursor introduced into the third zone 13 and the reactive gas introduced into the second zone 12 are maintained under conditions that are difficult to diffuse into the fifth zone 15.
Therefore, an inert gas such as helium, argon, nitrogen, carbon dioxide, or the like may be separately introduced into the fourth zone 14 and the fifth zone 15 as a purge gas.

  The plasma electrode 41 disposed in the second zone 12 includes a first electrode 42 and a second electrode 43. The first electrode 42 and the second electrode 43 may be laminated (bonded) in the X direction (left and right direction in FIG. 1), and in the X direction (left and right direction in FIG. 1), You may arrange | position in parallel at intervals. At this time, the first electrode 42 and the second electrode 43 are disposed without contacting each other.

The first electrode 42 is disposed such that the discharge surface 42a faces the film formation surface 50a of the flexible substrate 50 when the flexible substrate 50 passes through the second zone 12 in the first traveling direction. ing.
The second electrode 43 is disposed such that the discharge surface 43a faces the film formation surface 50a of the flexible substrate 50 when the flexible substrate 50 passes through the second zone 12 in the second traveling direction. ing.
The first electrode 42 and the second electrode 43 are electrically independent from each other.

  The first electrode 42 is connected to a first plasma activation mechanism (not shown), and the second electrode 43 is connected to a second plasma activation mechanism (not shown). The first plasma activation mechanism and the second plasma activation mechanism can be independently controlled. The first plasma activation mechanism and the second plasma activation mechanism include a power source for generating plasma in the first electrode 42 and the second electrode 43, a control device for controlling the power source, and the like. The first plasma activation mechanism and the second plasma activation mechanism preferably include a direct current power source as a main power source for plasma generation.

  Since the first electrode 42 and the second electrode 43 are electrically independent from each other, and the first electrode 42 and the second electrode 43 are connected to different plasma activation mechanisms, the first electrode 42 42 and the second electrode 43 can be independently controlled. That is, the first electrode 42 and the second electrode 43 can independently control input power, voltage, current, and the like.

  The material of the first electrode 42 and the second electrode 43 is not particularly limited as long as conductivity can be ensured. As the material of the first electrode 42 and the second electrode 43, a material having high electrical conductivity such as aluminum or copper and high thermal conductivity is preferably used.

As shown in FIG. 3, the plasma electrode 41 is obtained by integrating a flat plate-like first electrode 42 and a flat plate-like second electrode 43 with each other through a flat plate-like insulator 44. There may be.
The material of the insulator 44 is not particularly limited as long as the insulation between the first electrode 42 and the second electrode 43 can be secured. As a material of the insulator 44, glass, resin, ceramic, film, or the like is used.
Thus, by integrating the first electrode 42 and the second electrode 43 via the insulator 44, the first electrode 42 and the second electrode 43 can be electrically independent from each other. it can.

  For example, as shown in FIG. 4, the plasma electrode 41 includes a flat plate-like first electrode 42 and a flat plate-like second electrode 43 that are bonded together through a frame-like insulator 44 and integrated. It may be a thing. If the outer shapes of the first electrode 42, the second electrode 43, and the insulator 44 are substantially equal, the first electrode 42 and the second electrode 43 are bonded together via the frame-shaped insulator 44. Thus, a gap is formed between the first electrode 42 and the second electrode 43 by the opening 44 a formed inside the frame-shaped insulator 44. Thus, by using the frame-shaped insulator 44 having the opening 44a, the insulator 44 cools the refrigerant for cooling the first electrode 42 and the second electrode 43 with the first electrode 42 and the second electrode 43. It is possible to seal between the two electrodes 43. Thereby, the plasma electrode 41 can be provided with a cooling mechanism using a refrigerant.

  For example, as shown in FIG. 5, the plasma electrode 41 includes a tray-like first electrode 42 and a tray-like second electrode 43 that are bonded together through a frame-like insulator 44 and integrated. It may be a thing. Here, the tray shape is a flat plate shape as a whole, and only the edge portion of the flat plate protrudes upward from the flat plate, and the edge portion forms a wall. Moreover, that the edge part protrudes upwards from a flat plate means that the edge part is distribute | arranged perpendicularly | vertically or diagonally with respect to the flat plate. If the outer shapes of the first electrode 42, the second electrode 43, and the insulator 44 are substantially equal, the first electrode 42 so that the respective edge portions abut each other through the frame-shaped insulator 44. And the second electrode 43 are bonded together so that an opening 44a formed inside the frame-shaped insulator 44 is formed between the first electrode 42 and the second electrode 43, and a tray-shaped first electrode 43 is formed. A gap is formed by the one electrode 42 and the tray-like second electrode 43. Thus, by using the frame-shaped insulator 44 having the opening 44a, the insulator 44 cools the refrigerant for cooling the first electrode 42 and the second electrode 43 with the first electrode 42 and the second electrode 43. It is possible to seal between the two electrodes 43. Thereby, the plasma electrode 41 can be provided with a cooling mechanism using a refrigerant.

  In addition, the insulator 44 is provided with a groove for fitting an O-ring on the surface in contact with the first electrode 42 and the second electrode 43. By mounting an O-ring in this groove, the O-ring is in contact with the first electrode 42 and the second electrode 43, and the inner space of the insulator 44 (a gap formed by the opening 44a or the opening 44a, and a tray shape The gap between the first electrode 42 and the tray-like second electrode 43 is sealed.

  As the refrigerant, water, fluorocarbon-based gas, propane, propylene, butane, isobutane, carbon dioxide, ammonia, or the like is used. An insulating and liquid refrigerant can also be used.

  By sealing a coolant for cooling these electrodes between the first electrode 42 and the second electrode 43, overheating of the plasma electrode 41 can be prevented when the film forming apparatus 1 is used. . Thereby, it can prevent that the flexible base material 50 softens and the target atomic layer is no longer formed on the surface 50a of the flexible base material 50.

  4 and 5 exemplify the case where a frame-shaped insulator is used as the insulator 44, the present embodiment is not limited to this. As the insulator 44, not only one opening (cavity) 44a but also one having a flow path that defines the direction in which the refrigerant flows may be used.

Examples of the flexible substrate 50 include those made of a flexible material such as a plastic film, a plastic sheet, a metal foil, a metal sheet, paper, and a nonwoven fabric.
Although the thickness of the flexible base material 50 is not specifically limited, For example, they are 10 micrometers or more and 1000 micrometers or less.

According to the film forming apparatus 1 according to the present embodiment, the following effects can be obtained.
That is, since the plasma input power necessary for reacting each gas contributing to the film formation can be optimized, the film quality of the atomic layer deposition film can be improved. Further, by optimizing the plasma input power, excessive power supply can be suppressed and power consumption can be reduced. Further, by using the film forming apparatus 1, the apparatus can be reduced in size, and the heating mechanism for the apparatus can be reduced, so that power consumption can be further reduced and the amount of gas used can be suppressed. .

[Film formation method]
Next, a film forming method using the film forming apparatus 1 according to the present embodiment will be described.

  The film formation method according to the present embodiment includes a gas introduction process for introducing various gases into the film formation chamber 10, a reactive gas activation process for activating a reactive gas by exciting plasma, and a predetermined process. A base material transport step for transporting the flexible base material 50 along the film transport path P.

  First, the gas introduction process is started. In the gas introduction process, the first zone 11, the second zone 12, the third zone 13, the fourth zone 14, and the fifth zone 15 are removed from the exhaust ports provided in the respective zones by a vacuum pump. Apply vacuum. At the same time, from the inlets provided in the respective zones, the first precursor in the first zone 11, the reactive gas in the second zone 12, the second precursor in the third zone 13, and the fourth The purge gas is introduced into the zone 14 and the fifth zone 15. At this time, the film formation chamber 10 is heated as necessary, and the temperature of the film formation chamber 10 is maintained at a desired temperature.

By this gas introduction process, gas is introduced into each of the first zone 11, the second zone 12, the third zone 13, the fourth zone 14, and the fifth zone 15, and the gas in each zone. The concentration, pressure and distribution are adjusted.
The pressure in the fourth zone 14 is adjusted so as to be kept higher than the pressure in the first zone 11 and the pressure in the second zone 12. Further, the pressure in the fifth zone 15 is adjusted to be kept higher than the pressure in the second zone 12 and the pressure in the third zone 13.

  Subsequently, the reactive gas activation process is started while the gas introduction process is continued. In the reactive gas activation step, power is supplied to the first electrode 42 and the second electrode 43, and discharge from the first electrode 42 and the second electrode 43 is started. At this time, the first electrode 42 is supplied with electric power necessary and sufficient for the first precursor to react with the reactive gas that is the second gas. Similarly, the second electrode 43 is supplied with sufficient power necessary for the reaction of the second precursor and the reactive gas that is the second gas. When the cooling mechanism using the above-described refrigerant is provided in the plasma electrode 41, the cooling using the refrigerant is started before the discharge is started.

Then, a base material conveyance process is started, continuing a gas introduction process and a reactive gas activation process. In the substrate conveyance process, the flexible substrate 50 is conveyed along the film formation conveyance path P by rotating the unwinding roll and the winding roll.
The flexible substrate 50 is provided on one end side (side wall 10d side) of the film forming chamber 10, and is provided on the other end side (side wall 10c side) of the film forming chamber 10 from the unwinding chamber where the unwinding roll is arranged. The divided first zone 11, second zone 12, third zone 13, fourth zone 14, and fifth zone 15 are moved a plurality of times toward the take-up chamber in which the take-up roll is disposed. Along the reciprocating zigzag film formation conveyance path P, the film moves while being bent and deformed in the thickness direction.

  When paying attention to a part of the flexible substrate 50 in the conveyance direction (first traveling direction), the flexible substrate 50 is unwound from the unwinding roll and is first conveyed to the first zone 11. At this time, since the first precursor is introduced into the first zone 11, when the flexible base material 50 passes through the first zone 11, the first precursor is applied to both surfaces of the flexible base material 50. Adsorb.

  The conveyance speed of the flexible base material 50 in the first zone 11 is calculated from the saturated adsorption time and the passing distance so that the time for the flexible base material 50 to pass through the first zone 11 is longer than the saturated adsorption time. Is done. The saturated adsorption time is a time until the amount of the first precursor adsorbed on the film formation surface (both surfaces) of the flexible substrate 50 is saturated.

  Subsequently, the flexible base material 50 is conveyed to the fourth zone 14 through the opening 21 a of the first partition wall 21 provided between the first zone 11 and the fourth zone 14. Then, the surplus first precursor adsorbed on the flexible base material 50 is vaporized and purged while passing through the fourth zone 14 along the film forming conveyance path P. The conveyance speed of the flexible base material 50 in the fourth zone 14 is calculated from the passing distance so that a sufficient purge time can be obtained.

  Thereafter, the flexible base material 50 is conveyed to the second zone 12 through the opening 22 a of the second partition wall 22 provided between the fourth zone 14 and the second zone 12.

  A reactive gas is introduced into the second zone 12, and plasma is excited by at least one of the first electrode 42 and the second electrode 43. Therefore, while the flexible substrate 50 passes through the second zone 12, the discharge surface 42a of the first electrode 42 of the first precursor adsorbate adsorbed on the film formation surfaces (both surfaces) of the flexible substrate 50. Those facing the surface react with the reactive gas, and the target thin film (atomic layer) is formed. At this time, the first electrode 42 is supplied with sufficient electric power necessary for reacting the first precursor adsorbate adsorbed on the flexible substrate 50 with the reactive gas. As a result, the first precursor adsorbed on the flexible substrate 50 reacts with the reactive gas to generate a first reaction product.

  The conveyance speed of the flexible base material 50 in the second zone 12 is such that the time for the flexible base material 50 to pass through the second zone 12 is longer than the reaction time of the first precursor adsorbate and the reactive gas. It is calculated from the reaction time and the passage distance.

  After the first precursor adsorbate reacts with the reactive gas in the second zone 12, the flexible base material 50 has a third partition wall 23 provided between the second zone 12 and the fifth zone 15. Is transferred to the fifth zone 15 through the opening 23a. And while the flexible base material 50 passes the 5th zone 15 along the film-forming conveyance path P, the surplus reactive gas adsorbed by the flexible base material 50 is vaporized and purged. The conveyance speed of the flexible base material 50 in the fifth zone 15 is calculated from the passing distance so that a sufficient purge time can be obtained.

  Thereafter, the flexible base material 50 is conveyed to the third zone 13 through the opening 24 a of the fourth partition wall 24 provided between the fifth zone 15 and the third zone 13. At this time, since the second precursor is introduced into the third zone 13, the second precursor is applied to both surfaces of the flexible substrate 50 when the flexible substrate 50 passes through the third zone 13. Adsorb.

  The conveyance speed of the flexible base material 50 in the third zone 13 is calculated from the saturated adsorption time and the passing distance so that the time for the flexible base material 50 to pass through the third zone 13 is longer than the saturated adsorption time. Is done. The saturated adsorption time is a time until the amount of the second precursor adsorbed on the film formation surface (both surfaces) of the flexible substrate 50 is saturated.

  Subsequently, the flexible base material 50 is conveyed to the fifth zone 15 through another opening 24 a of the fourth partition wall 24 provided between the fifth zone 15 and the third zone 13. And while the flexible base material 50 passes the 5th zone 15 along the film-forming conveyance path P, the surplus 2nd precursor adsorb | sucked to the flexible base material 50 is vaporized and purged. The conveyance speed of the flexible base material 50 in the fifth zone 15 is calculated from the passing distance so that a sufficient purge time can be obtained.

  Thereafter, the flexible substrate 50 is conveyed to the second zone 12 through another opening 23 a of the third partition wall 23 provided between the second zone 12 and the fifth zone 15.

  A reactive gas is introduced into the second zone 12, and plasma is excited by at least one of the first electrode 42 and the second electrode 43. Therefore, while the flexible substrate 50 passes through the second zone 12, the discharge surface 43a of the second electrode 43 of the second precursor adsorbate adsorbed on the film formation surfaces (both surfaces) of the flexible substrate 50. Those facing the surface react with the reactive gas, and the target thin film (atomic layer) is formed. At this time, the second electrode 43 is supplied with sufficient power necessary for reacting the second precursor adsorbate adsorbed on the flexible substrate 50 with the reactive gas. As a result, the second precursor adsorbed on the flexible substrate 50 reacts with the reactive gas to produce a second reaction product.

  The conveyance speed of the flexible base material 50 in the second zone 12 is such that the time for the flexible base material 50 to pass through the second zone 12 is longer than the reaction time of the second precursor adsorbate and the reactive gas. It is calculated from the reaction time and the passage distance.

  Subsequently, the flexible base material 50 is conveyed to the fourth zone 14 through another opening 22 a of the second partition wall 22 provided between the fourth zone 14 and the second zone 12. Then, surplus reactive gas adsorbed on the flexible base material 50 is vaporized and purged while passing through the fourth zone 14 along the film-formation conveyance path P. The conveyance speed of the flexible base material 50 in the fourth zone 14 is calculated from the passing distance so that a sufficient purge time can be obtained.

  Thereafter, the flexible base material 50 is conveyed again to the first zone 11 through another opening 21 a of the first partition wall 21 provided between the first zone 11 and the fourth zone 14. The

  Strictly speaking, the above steps are two cycles of atomic layer deposition, and two atomic layers are deposited on the flexible substrate 50 by these two cycle steps. By repeating these two cycles a plurality of times, an atomic layer deposition film having a desired thickness can be formed on one surface of the flexible substrate 50. After the atomic layer deposition film having a desired thickness is formed, the flexible substrate 50 is wound up by a winding roll.

  When the above two cycles are repeated a plurality of times, the conveyance speed of the flexible base material 50 is such that the flexible base material 50 has the first zone 11, the second zone 12, the third zone 13, the fourth zone 14, and the like. It is set to the lowest speed among the conveyance speeds calculated from the time required for passing through the fifth zone 15 and the passing distance through which the flexible base material 50 passes through each zone.

According to the film forming method of the present embodiment, the following effects can be obtained.
That is, since the plasma input power necessary for reacting each gas contributing to the film formation can be optimized, the film quality of the atomic layer deposition film can be improved. Further, by optimizing the plasma input power, excessive power supply can be suppressed and power consumption can be reduced. In addition, by using the film forming apparatus 1 described above, the apparatus can be reduced in size and the heating mechanism for the apparatus can be reduced, so that power consumption can be further reduced and the amount of gas used can be suppressed. Can do.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.

  A film forming apparatus having the same basic structure as the film forming apparatus 1 shown in FIG. 1 was used, and a polyethylene terephthalate (PET) film having a width of 300 mm and a thickness of 100 μm was used as the flexible substrate 50. After attaching this PET film to the unwinding roll installed in the unwinding chamber, it is unwound from the unwinding roll, and as shown in FIG. 1, the first zone 11, the second zone 12, the third zone It passed through a zigzag film-formation conveyance path P that reciprocates a plurality of times in the zone 13, the fourth zone 14, and the fifth zone 15, and passed to a winding roll installed in the winding chamber.

  Next, the unwinding chamber, the film forming chamber 10, and the winding chamber were evacuated by a vacuum pump.

  Next, the film formation chamber 10 was heated to 75 ° C.

  Next, supply of nitrogen gas as a purge gas to the fourth zone 14 and the fifth zone 15 was started, and supply of oxygen gas as a reactive gas to the second zone 12 was started.

Next, supply of trimethylaluminum as the first precursor to the first zone 11 was started, and supply of titanium tetrachloride (TiCl ₄ ) as the second precursor to the third zone 13 was started.

  At this time, by adjusting the flow rate and displacement of each gas, the pressure in the fourth zone 14 is kept higher than the pressure in the first zone 11 and the pressure in the second zone 12, The pressure in the fifth zone 15 was kept higher than the pressure in the second zone 12 and the pressure in the third zone 13. However, since the pressure difference is extremely small, in order to detect the pressure difference, it is necessary to use a precise and highly accurate pressure gauge and to calibrate the pressure gauge strictly before use.

  In the present embodiment, although not shown in the drawing, the guide rollers 31 and 32 are provided at positions corresponding to the respective guide rollers 31 and 32 disposed in the film forming chamber 10. There are as many as there are. One exhaust port is provided in each of the first zone 11, the second zone 12, and the third zone 13.

Here, the plasma electrode 41 is integrated by connecting the first electrode 42 and the second electrode 43 with an insulator interposed therebetween, but the first electrode 42 and the second electrode 43 are made of an insulator. Electrically independent. In this embodiment, the insulator is made of resin and has a frame shape. By passing cooling water through the inside of the plasma electrode 41 through a cooling water inlet / outlet (not shown) arranged so as to be adjacent to the film forming chamber 10, the plasma electrode 41 can be cooled from the inside. The insulator is provided with a groove into which an O-ring is fitted on the surface in contact with the first electrode 42 and the second electrode 43. By mounting an O-ring in this groove, the O-ring comes into contact with the first electrode 42 and the second electrode 43, and the inside of the insulator is sealed.
The first electrode 42 and the second electrode 43 are connected to different DC power sources (not shown) and controlled independently.

  Next, cooling water was supplied into the plasma electrode 41 and water cooling was started.

  Next, a voltage was applied to the first electrode 42 and the second electrode 43 installed in the second zone 12 to start glow discharge. At this time, 1.2 kW was input to the first electrode 42 as a power sufficient to react the first precursor adsorbed on the flexible base material 50. Similarly, 1.5 kW was input to the second electrode 43 as a sufficient power necessary for reacting the second precursor adsorbed on the flexible substrate 50.

  The conveyance of the flexible base material 50 was started at a speed of 1 m / min, and film formation on the surface of the flexible base material 50 was started.

  The flexible base material 50 (60) formed in the film forming chamber 10 was transported to the winding chamber and collected.

  In addition, this invention is not limited to the above-mentioned embodiment and Example. In the above-described embodiment, the web coating method is adopted as an example, and the example targeting the flexible substrate 50 has been shown, but the present invention is not limited to this. For example, not only the flexible substrate 50 but also a method of continuously depositing a substrate to be deposited on a flexible sheet that can be continuously transported or a partly flexible tray and transporting it. .

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. In addition, the specific configuration, material, and the like of each part are not limited to those illustrated in the above-described embodiment, and can be changed as appropriate.

  According to the film forming apparatus and the film forming method of the present invention, it is possible to continuously form a film on a thin wound base material to form a dense thin film, and a metallic luster film used for gold and silver thread, It can be used as a gas barrier film for food packaging, an electrode of a film capacitor, an optical film manufacturing apparatus and a manufacturing method for antireflection and the like.

1 Deposition equipment,
DESCRIPTION OF SYMBOLS 10 Deposition chamber 11 1st zone 12 2nd zone 13 3rd zone 14 4th zone 15 5th zone 21, 22, 23, 24 Partition 31, 32 Guide roller 41 Plasma electrode 42 1st electrode 43 Second electrode 50, 60 Flexible substrate

Claims (5)

A first zone into which a first gas containing metal or silicon is introduced;
A second zone into which a second gas is introduced;
A third zone into which a third gas containing metal or silicon is introduced;
A partition wall having an opening through which the flexible substrate passes through the first zone, the second zone, and the third zone;
By moving the flexible substrate in a first traveling direction or a second traveling direction opposite to the first traveling direction, the flexible substrate is moved into the first zone and the second zone. And one cycle of atomic layers for forming one atomic layer on the film forming surface of the flexible substrate by atomic layer deposition by passing the third zone a plurality of times in this order or in the reverse order. A film-conveying path in which the deposition cycle is performed a plurality of times;
A first electrode and a second electrode for plasma activation disposed in the second zone;
A film forming chamber having at least
The first electrode is connected to a first plasma activation mechanism, and a discharge surface of the first electrode is formed when the flexible substrate passes through the second zone in the first traveling direction. Relative to the film-forming surface of the flexible substrate,
The second electrode is connected to a second plasma activation mechanism, and the discharge surface of the second electrode is when the flexible substrate passes through the second zone in the second traveling direction. Relative to the film-forming surface of the flexible substrate,
The film forming apparatus, wherein the first plasma activation mechanism and the second plasma activation mechanism can be independently controlled.   The film forming apparatus according to claim 1, wherein the first plasma activation mechanism and the second plasma activation mechanism include a direct current power source as a main power source for generating plasma.   The film forming apparatus according to claim 1, wherein the first electrode and the second electrode are bonded to each other through an insulator and integrated.   The said insulator has a structure which seals the refrigerant | coolant for cooling said 1st electrode and said 2nd electrode between said 1st electrode and said 2nd electrode. Item 4. The film forming apparatus according to Item 3. Using the film forming apparatus according to any one of claims 1 to 4,
A film forming method, wherein the first plasma activation mechanism and the second plasma activation mechanism are controlled independently to form a thin film on a main film formation surface of the flexible substrate.

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