JPH02431B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for forming a thin film by arranging electrodes in a coaxial manner and utilizing plasma generated between the electrodes, and particularly relates to a device for continuously coating a flexible substrate with a thin film. The present invention relates to a thin film forming device for the purpose of forming a thin film.

Conventionally, apparatuses for forming thin films using plasma, in which the substrate on which the film is deposited can be moved and thin films can be continuously formed, are shown in Fig. 1 or 2. The ones shown in are known.

Figure 1 shows a high-frequency electrode 2 inside a thin film forming chamber 1.
A rotatable roller-type ground electrode 3 is disposed opposite the ground electrode 3, and a feed reel 5 for feeding out the flexible substrate 4 is placed on one side of the ground electrode 3, and a winding reel 5 for winding up the flexible substrate 4 is placed on the other side of the ground electrode 3. This is a sputtering device in which a take-up reel 6 is installed and a flexible substrate 4 is moved from a delivery reel 5 to a take-up reel 6 as shown by an arrow 7. Further, FIG. 2 shows a delivery chamber 8 in which a parallel plate type high-frequency electrode 2 and a ground electrode 3 are disposed opposite each other in the thin film production chamber 1, and a delivery reel 5 is installed on one side of the thin film production chamber 1. and a take-up chamber 9 with a take-up reel 6 installed on the other side, and the flexible substrate 4 is moved from the delivery reel 5 to the take-up reel 6 as shown by the arrow 7. It is a CVD device. However, these first
The thin film forming apparatuses shown in the figures and FIG. 2 are all apparatuses that apply parallel plate type plasma apparatuses, and the use efficiency of the reaction gas flowed into the thin film forming chamber 1 to generate plasma or the sputtering material is important. There were some disadvantages in terms of utilization efficiency.

In terms of these efficiencies, it is known that a so-called coaxial type sputtering device or plasma CVD device in which the high frequency electrode 2 and the ground electrode 3 are arranged coaxially is superior. However, in the conventional coaxial type thin film forming apparatus, one that can move the substrate on which the film is deposited and continuously form the thin film has not been provided to date.

In addition, when creating a thin film, if it is necessary to draw a predetermined pattern on the thin film, for example when the application is for solar cells, patterning is performed by placing a mask on the substrate on which the film is deposited. things will be done. However, in the above-mentioned device,
There was also the problem that patterning could not be performed due to its structure.

The present invention has been made in view of the above-mentioned problems, and its purpose is to provide an apparatus to which a coaxial type plasma apparatus is applied, which is excellent in terms of the efficiency of using reaction gas or the efficiency of using sputtering material. An object of the present invention is to provide a thin film forming apparatus that can continuously form thin films.

Another object of the present invention is to provide a thin film forming apparatus that can perform patterning during the thin film forming process.

According to the present invention, a preliminary chamber is provided adjacent to the thin film forming chamber to prevent gas harmful to thin film forming from entering the thin film forming chamber, and to prevent gases contained in the thin film forming chamber from entering the thin film forming chamber. The electrodes are arranged coaxially with a central axis, and a passage for a flexible substrate to be coated is provided in the thin film forming chamber so that its cross-sectional shape is within the space between the coaxial electrodes from the preliminary chamber and at the center. In the apparatus for forming a thin film on the flexible substrate using plasma generated between the coaxial electrodes, which is formed so as to pass through a circumference around an axis and reach the preparatory chamber again. The passageway in the thin film forming chamber is formed via a guide frame that slides or engages with the edge of the flexible substrate and is driven in synchronization with the movement of the flexible substrate. A thin film forming apparatus characterized by the following can be obtained.

Further, according to the present invention, the passage through which the flexible substrate passes in the thin film forming chamber is configured via a guide frame that is driven in synchronization with the movement of the flexible substrate, and the guide frame is provided with a flexible substrate. A thin film forming apparatus is obtained in which a mask plate is disposed in close contact with a transparent substrate.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 3 is a plan view showing the configuration of an embodiment of the thin film forming apparatus according to the present invention, in which a high frequency electrode 12 is arranged on the central axis of a cylindrical chamber 11 to form a thin film forming chamber 13. A preliminary chamber 14 is installed adjacent to the thin film forming chamber 13, and the thin film forming chamber 13 and the preliminary chamber 14 are connected to a passage 1 having a rectangular cross section.
5 and 16, and a film storage chamber 17 is installed adjacent to the preliminary chamber 14.
The film storage chamber 17 is connected to a passage 18, 1 having a rectangular cross section.
9 is used for communication.

A vacuum exhaust system 20 is connected to the thin film forming chamber 13, preliminary chamber 14, and film storage chamber 17, respectively, to evacuate each chamber 13, 14, and 17, and to evacuate each chamber 13, 14, and 17, respectively. It has a differential pumping configuration to maintain a predetermined degree of vacuum. Inside the film storage chamber 17, there is a flexible film 21 that will serve as a substrate for depositing a thin film.
A delivery reel 22 and a take-up reel 23 are rotatably installed. The film 21 is unwound from the feed reel 22, passes through the passage 18, enters the preliminary chamber 14, then passes through the passage 15, enters the thin film forming chamber 13, and enters the thin film forming chamber 1.
From inside 3, the film passes through a passage 16 and enters the preparatory chamber 14 again, then passes through a passage 19 and enters the film storage chamber 17 again, where it can be wound on a take-up reel 23.

Inside the thin film forming chamber 13, a guide roller 24 and a guide roller 25 are installed in the vicinity of the passage 15 and 16, respectively. As shown, a guide frame 26 is installed, and a passage is formed so that the film 21 guided into the thin film forming chamber 13 passes through the guide frame 26 on a circumference coaxial with the high-frequency electrode 12. 27 is formed.
The film 21 that has passed through the passage 15 from the preliminary chamber 14 side and entered the thin film forming chamber 13 is moved by the guide roller 24 in the thin film forming chamber 13.
The edge of the film 21 passes through the gap between the guide frame 26 and the guide frame 26, and the edge of the film 21 comes into sliding contact with the guide frame 26, while going around the inside of the thin film forming chamber 13 along the path. Thereafter, this film 21 passes through the gap between the guide roller 25 and the guide frame 26 in the thin film forming chamber 13, and passes through the passage 1.
6 and move toward the preliminary chamber 14 side.

In addition, in FIG. 3, 28 is a high frequency power supply, 29
Reference numeral 30 indicates a heater disposed outside the guide frame 26, and reference numeral 30 indicates a gas introduction system 31 which indicates a preheating lamp installed within the preparatory chamber 14. Furthermore, 40 indicated by a dotted line in FIGS. 3 and 4 is a slightly rigid film that is accompanied by the film 21, and includes guide rollers 24, 25, a tension applying roller 41,
It runs along the back surface of the film 21 and the outer periphery of the heater 29. This allows the film 21 to be moved through the guide frame 26.
This prevents wrinkles from forming on the film 21. Therefore, if the film 21 has sufficient rigidity, it can be omitted.

In the above configuration, each vacuum exhaust system 2
0, 20, and 20 are driven to evacuate the preliminary chamber 14 of the thin film forming chamber 13 and the film storage chamber 17, and a predetermined reaction gas (for example, SiH ₄
+H ₂ +B ₂ H ₆ ) is introduced and the high-frequency output of the high-frequency power supply 28 is applied to the high-frequency electrode 12 , a reactive gas plasma is generated between the high-frequency electrode 12 and the wall of the chamber 11 , and the plasma around the high-frequency electrode 12 is generated. A predetermined thin film can be deposited on the surface of the film 21 placed on the surface. Therefore, a feed reel 22 and a take-up reel 23 installed in the film storage chamber 17 are
By driving the film 21 to sequentially move the film 21 in the direction of the arrow 32, a thin film can be continuously deposited on the surface of the film 21. The thickness of the thin film deposited on the surface of the film 21 at this time is determined by the pressure inside the thin film forming chamber 13, the power applied by the high frequency power supply 28, and the moving speed of the film 21.

The material of the film 21 is not limited as long as it is flexible, and a polymer film, stainless steel or other metal film can be used as a substrate for forming a thin film. The preheating lamp 31 installed in the preparatory chamber 14 and the heater 29 installed in the thin film forming chamber 13 are used to remove impurity gas occluded in the film 21. Preheating lamp 31 in chamber 14
After being preheated by
Main heating is performed by a heater 29 inside.

The preliminary chamber 14 (the same applies to the film storage chamber 17) is connected to the vacuum evacuation system 20 to form a differential pumping configuration between the thin film forming chamber 13, but the point is that the thin film forming chamber is connected to the thin film forming chamber 13 through the passages 15 and 16. Since it is important that harmful gases (for example, oxygen) do not enter into the chamber 13 during the thin film production process, the chamber 14 is used as a gas purge chamber in which a harmless gas is sent into the preliminary chamber 14 and the harmful gas is expelled from the system. Also good.
Further, the preliminary chamber 14 may be configured as separate chambers by separating the front side, ie, the film supply side, and the rear side, ie, the film discharge side, of the thin film forming chamber 13, as in an embodiment shown later.

Next, regarding the coaxial type electrode configuration arranged inside the thin film forming chamber 13, the one shown in FIG. An electromagnet such as a Helmholtz coil may be fitted outside the thin film forming chamber 13 to apply a magnetic field to the plasma generation space, thereby controlling the plasma density. In the case of the permanent magnet, it is connected to the high frequency electrode 12
A drive mechanism that can be moved in the axial direction may be attached to change the magnetic field that acts on the plasma.

Further, as shown in FIG. 5, a cylindrical mesh 50 may be disposed between the high-frequency electrode 12 and the film 21 and coaxial with the high-frequency electrode 12. By placing the mesh 50 at ground potential, the inside and outside of the mesh 50 can be electrically separated into a discharge space, which is a plasma space, and a film deposition space, thereby improving film quality and productivity. In FIG. 5, 51 is an insulator.

Furthermore, as shown in FIG.
is constructed of a cylindrical mesh and the diameter of the cylinder is increased, and when it is placed concentrically close to the grounded cylindrical mesh 50, no discharge occurs in the narrow gap between the electrodes 12 and 50, and the internal At 52, a hollow cathode discharge accompanied by intense light is generated. In this case, the separation between the film deposition space and the discharge space becomes stronger, and the film deposition rate increases further due to the participation of strong plasma generation and photochemical activation. Moreover, the film quality is good.

Next, the guide frame 26 may be engaged with the edge of the film 21, as shown in FIG. That is, engagement holes 33, 33 are bored at a constant pitch in the edge of the film 21, and
Engagement protrusions 34, 34 are provided protruding from the abutting portion of the guide frame 26 at the same pitch as the engagement holes 33, 33 of the film 21, so that the engagement protrusions 34, 34 fit into the engagement holes 33, 3.
3, it is fitted and latched in sequence. In this case, the guide frame 26 should be provided with a structure that can be easily rotated with a light force of film winding, or the feed reel (FIG. 3) and the take-up reel 23 (FIG. 3) should be provided. Needless to say, a drive device synchronized with the circumferential speed of the guide frame 26 is provided to drive the guide frame 26 during operation of the device. When the moving path for the film 21 is constructed through the guide frame 26 which is driven and rotated in this manner, there is an advantage that even a film having relatively low rigidity can be transported without wrinkles.
A disk 3 constitutes an engaging portion with the film 21.
As shown in the figure, a mask plate 36 may be provided between the film 21 and the film 21 in close contact with the inner surface thereof. Since the mask plate 36 rotates periodically with the movement of the film 21, it is possible to draw a certain pattern on the film deposited on the film 21.

FIGS. 8 and 9 show an embodiment in which the basic model of the embodiment of the present invention shown in FIG. 3 is expanded, and a plurality of thin film forming chambers are arranged in series.

Referring to FIG. 8, three thin film forming chambers 13a, 13b, and 13c are arranged in series, with a film storage chamber 17a disposed on one side via a passage 18, and a film storage chamber 17a on the other side. 17b is arranged via the passage 19. Also, each room 13a,
13b and 13c have preliminary rooms 14a and 14b, respectively.
14c is the passage 15a, 16a, 15b, 16b,
They are arranged via 15c and 16c. The flexible film 21 is unwound from the delivery reel 22 in the film storage chamber 17a, passes through the three thin film forming chambers 13a, 13b, and 13c in sequence, and then transferred to the take-up reel 23 in the film storage chamber 17b. It is wound up. Therefore, three layers can be formed in succession on the film 21. In the figure, 37a and 37b are protective films for protecting the surface (film deposition surface) of the film 21. When a plurality of thin film forming chambers are installed in series like this, it is not necessarily necessary to use the same thin film forming method, but it is of course possible to use chambers, plasma CVD, and sputtering depending on the purpose.

Also, referring to FIG. 9, three thin film forming chambers 13a, 13b, 13c are arranged in series, and separate preliminary chambers 14a, 14b, 14c are provided on the front and rear sides of each thin film forming chamber 13a, 13b, 13c. ,1
4d, the preliminary chamber 14b on the rear side of the thin film forming chamber 13a also serves as the preliminary chamber on the previous side of the thin film forming chamber 13b, and similarly the preliminary chamber 14c on the rear side of the thin film forming chamber 13b serves as the preliminary chamber on the preceding side of the thin film forming chamber 13b. It also serves as a spare room on the front stage side. High frequency electrodes 12a, 12b, 12c are horizontally installed in each thin film forming chamber 13a, 13b, 13c, respectively, to form a horizontally coaxial electrode arrangement. In this apparatus, the film 21 is stored in the film storage chamber 17a, the preliminary chamber 14a, the thin film forming chamber 13a, the preliminary chamber 14b, and the thin film forming chamber 13.
b, pass through the preparatory chamber 14c, the thin film forming chamber 13c, and the preparatory chamber 14d in this order, and enter the film storage chamber 17.
Moving to step b, a three-layer film can be successively created in the same manner as the example shown in FIG. In each thin film forming chamber 13a, 13b, 13c, passages 27a, 27b, 27c for the film 21 are provided.
It is formed over an angular range of 180 degrees, and the film is deposited on the film 21 in a downward state. When the electrodes are arranged horizontally as in this example, if the film is deposited upward, there is a risk of dust entering the film, which will impair the properties of the film, so the film should be deposited downward. Passages 27a, 27b, 2
It is desirable to form 7c. Its angular range is
Although the angle is 180 degrees or less, a range of 90 degrees to 180 degrees is considered preferable considering space utilization.

Although the example of expanding the basic type has been described above, it goes without saying that it can be implemented in various ways other than the above. And in these implementation devices,
It goes without saying that the various modifications described in the basic model can be employed.

As detailed above, the present invention is an apparatus that applies a coaxial plasma apparatus, and is an apparatus that can continuously convey a flexible film, which is a substrate on which a film is deposited, to a film deposition space. Therefore, the reaction gas usage efficiency or the sputtering material usage efficiency can be maintained at a high level, and a desired film can be continuously formed on a flexible film. Furthermore, the passage for the film in the thin film forming chamber is configured via a guide frame that is driven in synchronization with the moving speed of the film, and a mask plate that is in close contact with the film is disposed on this guide frame. It also has the effect of allowing a certain pattern to be drawn on the film that is formed.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the configuration of a conventional device.
FIG. 2 is a sectional view showing another example of the configuration of the conventional device, FIG. 3 is a plan view showing the configuration of an embodiment of the thin film forming device according to the present invention, and FIG. 4 is the guide frame of FIG. 3. FIG. 5 is a schematic view showing the structure of a thin film forming chamber of an embodiment of the thin film forming apparatus according to the present invention; FIG. 6 is a partially cutaway cross-sectional view showing the structure of an embodiment of the thin film forming apparatus according to the present invention. A schematic diagram showing the configuration of another embodiment of the thin film forming chamber, FIG.
FIG. 8 is a partially cutaway front view showing the structure of another embodiment of the guide frame shown in the figure, FIG. 8 is a plan view showing the structure of another embodiment of the thin film forming apparatus according to the present invention, and FIG. FIG. 3 is a front view showing the configuration of still another embodiment of the thin film forming apparatus according to the invention. 12, 12a, 12b, 12c...High frequency electrode, 13, 13a, 13b, 13c...Thin film forming chamber, 14, 14a, 14b, 14c, 14
d...Preliminary room, 15, 15a, 15b, 15c...
...Aisle, 16, 16a, 16b, 16c...Aisle, 17, 17a, 17b...Film storage chamber,
18, 19... passage, 21... film, 22...
...Delivery reel, 23...Take-up reel, 26...
...Guide frame, 27, 27a, 27b, 27c...
Passage, 31... Preheating lamp, 34... Engaging protrusion, 36... Mask plate, 50... Cylindrical mesh.

Claims (1)

[Scope of Claims] 1. A preliminary chamber is provided adjacent to the thin film forming chamber to prevent gases harmful to thin film forming from entering the thin film forming chamber, and to prevent gases contained in the thin film forming chamber from entering the thin film forming chamber. The electrodes are arranged coaxially with a central axis, and a passage for a flexible substrate to be coated is provided in the thin film forming chamber so that its cross-sectional shape extends from the preparatory chamber to within the space between the coaxial electrodes and In an apparatus for forming a thin film on the flexible substrate using plasma generated between the coaxial electrodes, which is formed so as to pass through a circumference around a central axis and reach the preparatory chamber again, The passageway in the thin film forming chamber is formed via a guide frame that slides or engages with the edge of the flexible substrate and is driven in synchronization with the movement of the flexible substrate. A thin film forming device characterized by the following. 2. The thin film forming apparatus according to claim 1, wherein the thin film forming chamber has a magnet for trapping the plasma generated between the coaxial electrodes. 3. The thin film forming apparatus according to claim 2, wherein the magnet is a permanent magnet placed inside the center electrode of the coaxial electrode. 4. A permanent magnet disposed inside the center electrode,
4. The thin film forming apparatus according to claim 3, wherein the thin film forming apparatus is disposed so as to be movable in the axial direction of the center electrode. 5. The thin film forming apparatus according to claim 2, wherein the magnet is an electromagnet fitted outside the thin film forming chamber. 6 Patent that the thin film forming chamber has a cylindrical mesh for electrically separating the plasma space generated between the coaxial electrodes and the thin film deposition space on the passage side of the flexible substrate. Claim 1
The thin film forming apparatus described in . 7 The coaxial type electrode of the thin film forming chamber is
A patent claim consisting of a concentric circular cylindrical mesh high-frequency electrode and a ground electrode adjacent to the high-frequency electrode, the mesh having a hollow cathode discharge inside and a thin film deposition space for the flexible substrate outside. The thin film forming apparatus according to item 1. 8. A mask in which a guide frame driven in synchronization with the movement of the flexible substrate is stretched so as to be in close contact with the inner surface of the flexible substrate while engaging with the edge of the flexible substrate. A thin film forming apparatus according to claim 1, comprising a plate. 9 The passageway in the thin film forming chamber is 90
2. The thin film forming apparatus according to claim 1, wherein the thin film is formed over an angular range of 1° or more. 10. The thin film forming apparatus according to claim 1, wherein a plurality of the thin film forming chambers are arranged in series.