JP2001003170A - Film forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film forming device with which the working rate of a film forming line is increased and the productivity is improved by preventing the deposition of a film on the wall face, or the like, of an exhausting passage. SOLUTION: In a film forming device provided with a film forming furnace 60 demarcating a space storing a glass substrate, a feed tube 61 feeding the raw material of a film to the inside of the film forming furnace 60 and an exhaust tube 62 exhausting the inside of the film forming furnace, and forming a film on the surface of a substrate by a chemical vapor phase film forming method, a heat insulating member 72 is provided on the outer wall face of the exhaust tube 62 and also in the region disposed with a pressure gauge 70 and a stop valve 71.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming apparatus for forming a film on a substrate by a CVD method (chemical vapor deposition method), and more particularly to a film forming apparatus for forming an SiO ₂ film or the like on a glass substrate or the like. About.

[0002]

2. Description of the Related Art When manufacturing an ITO glass substrate used as a display unit such as a calculator, a clock, a timer, or a liquid crystal display unit such as a digital camera or an input touch panel connected to a computer, a cleaning device and a sorting machine are used. A production line including an apparatus, a transport apparatus, a film forming apparatus, and the like is used.

In a film forming apparatus in this production line, C
A film forming method based on the VD method is used. In this film forming method, a raw material chemical is heated and evaporated to a gaseous phase to form a film on a glass substrate.

[0004]

This film forming technique by the CVD method utilizes a reaction by contact between an active ingredient of a raw material chemical in a gaseous phase and a solid, so that an effective ingredient that can be a film can be circulated. In the region, a film is formed for any solid. As a result, the SiO ₂ film or the ITO film is formed not only on the glass substrate but also on the inner wall surface of the film forming furnace, the surface of the belt conveyor for transporting the glass substrate, and the like.

In particular, in the region of the exhaust passage remote from the center of the film forming furnace, the exhaust gas temperature tends to decrease, so that the generated SiO ₂ particles adhere to the inner wall surface of the exhaust passage and cause the exhaust passage to close. If clogging occurs and this clogging occurs in the area where the pressure gauge and the opening / closing valve are arranged, the exhaust gas flow rate cannot be adjusted, and the film formation itself cannot be performed. Furthermore, if the attached particles fall on the glass substrate as exfoliated pieces, that is, dust, they cause defects such as pinholes on the ITO glass substrate.

Accordingly, in order to prevent the above-described clogging or defects of the exhaust passage, the film forming apparatus is periodically dismantled, for example, every several hours, and the SiO ₂ film adhering to the inner wall surface of the exhaust passage is removed. Cleaning work was carried out to peel off and remove the like. During this cleaning work, it is needless to say that the film forming process in the film forming line must be interrupted.
Even if one film forming line is being cleaned, the film forming process in another film forming line must be interrupted, and there is a problem that productivity is reduced.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to prevent a film from adhering to a wall or the like of an exhaust passage and to form a film forming line. It is an object of the present invention to provide a film forming apparatus capable of improving an operation rate and improving productivity.

[0008]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has come to find an invention having the following structure. That is, the film forming apparatus of the present invention includes a film forming furnace for defining a space for accommodating a substrate, a material supply passage for supplying a film material to the inside of the film forming furnace, and an exhaust for exhausting the inside of the film forming furnace. A film forming apparatus for forming a film on the surface of the substrate by a chemical vapor deposition method, comprising a passage connected to at least a film forming furnace around a wall defining the exhaust passage. , A heat insulating member is provided in the vicinity of. According to this configuration, the heat insulating member acts to block heat from escaping from the wall surface of the exhaust passage. Therefore, a decrease in the temperature of the exhaust gas flowing in the exhaust passage is prevented, and the adhesion of the effective component in a gaseous state that can be a film, for example, SiO ₂ particles, to the inner wall surface of the exhaust passage is prevented or suppressed.

In the above structure, the exhaust passage is provided with a flow rate adjusting means for adjusting the flow rate of the exhaust gas flowing therein, and the heat insulating member is arranged so as to include a region where the flow rate adjusting means is provided. Configuration can be adopted,
Further, as the flow rate adjusting means, a configuration having at least a pressure gauge or an on-off valve can be adopted. According to this configuration, the heat insulating member acts to block heat from escaping from the wall surface of the exhaust passage. Therefore, a decrease in the temperature of the exhaust gas flowing in the exhaust passage is prevented, and the effective component in a gaseous state, for example, SiO ₂ particles, which can form a film, adheres to the inner wall surface of the exhaust passage in the region where the flow rate control means is provided. Is prevented or suppressed. As a result, the intended function of the flow rate adjusting means is maintained for a long time.

A film forming apparatus according to the present invention includes a film forming furnace for defining a space for accommodating a substrate, a material supply passage for supplying a film material to the inside of the film forming furnace, and an exhaust inside the film forming furnace. An exhaust path, comprising: a film forming apparatus that forms a film on the surface of a substrate by a chemical vapor deposition method, wherein at least a wall around a wall defining the exhaust path is connected to a film forming furnace. In the vicinity of the region, a heating means for heating exhaust gas flowing inside is provided. According to this configuration, the wall of the exhaust passage is heated by the heating means, and the exhaust gas flowing in the exhaust passage is adjusted to a desired temperature. Therefore, the active ingredient in a gaseous state that can be a film, for example, Si
The adhesion of O ₂ particles and the like to the inner wall surface of the exhaust passage is prevented or suppressed.

In the above configuration, the exhaust passage is provided with a flow rate adjusting means for adjusting the flow rate of the exhaust gas flowing therein, and the heating means is arranged so as to include a region provided with the flow rate adjusting means. Configuration can be adopted,
Further, as the flow rate adjusting means, a configuration having at least a pressure gauge or an on-off valve can be adopted. According to this configuration, the wall of the exhaust passage is heated by the heating means, and the exhaust gas flowing in the exhaust passage is adjusted to a desired temperature. Therefore, the adhesion of the effective component in a gaseous state that can be a film, for example, SiO ₂ particles to the inner wall surface of the exhaust passage is prevented or suppressed. As a result, the intended function of the flow rate adjusting means is maintained for a long time.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIGS. 1 and 2 are schematic structural views showing a film forming apparatus according to the present invention. In a production line equipped with this film forming apparatus, a liquid crystal display such as a calculator, a clock, a timer, and a digital camera, an electroluminescence The present invention is to manufacture an ITO glass substrate used as a display, a surface heating element, a touch panel for input connected to a computer, and the like.

In this production line, a glass substrate as a raw material is first sent to a cleaning device in a state packed in a cassette, and the glass substrate is cleaned. In this cleaning step, the cassette is immersed in a cleaning tank, ultrasonically used to remove dirt attached to the surface of the glass substrate, rinsed with tap water, pure water, etc., replaced with IPA (isopropyl alcohol), and finally vaporized with IPA vapor. And dry.

When the cleaning step is completed, the destination of the cassette is selected by the sorting device according to the size of the glass substrate, and is selectively sent out to each of the film forming lines of the film forming device including a plurality of lines. .

The film forming apparatus uses a pyrosol film forming method, which is a kind of normal pressure CVD method. In this film forming process, a cassette (not shown) is used in each film forming line using a robot (not shown). The glass substrate is taken out and placed on the transport means. Then, the glass substrates are preliminarily heated to about 500 ° C. while being conveyed one by one, and an SiO ₂ film and an ITO film are sequentially laminated on the heated glass substrate. Subsequently, the glass substrate on which these films are formed, that is, the ITO glass substrate is cooled to room temperature.

Each of the film forming lines of the above film forming apparatus includes:
As shown in FIGS. 1 and 2, a belt conveyor 50 that continuously conveys a glass substrate in one direction in a state where the glass substrate is placed, and covers a part of the belt conveyor 50 and a glass substrate placed on the belt conveyor. A film-forming furnace for defining a space, ie, S
A plurality of first film forming furnaces 60 for forming the iO ₂ film and a plurality of second film forming furnaces 80 for forming the ITO film, and film raw materials are provided inside the first film forming furnace 60 and the second film forming furnace 80. Supply pipes 61 and 81 for defining a raw material supply passage for supplying the gas, and exhaust pipes 62 and 82 for defining exhaust paths for exhausting the insides of the first film forming furnace 60 and the second film forming furnace 80.

The first film forming furnace 60 is provided on the upstream side of the film forming apparatus, and as shown in FIG.
Has a muffle body 63 surrounding the upper surface of the substrate and defining a film formation space. The muffle body 63 extends in the horizontal direction and has a belt conveyor 50 on which a glass substrate is placed.
, A transfer passage 63a having a substantially rectangular cross section, a chamber 63b projecting upward from the upper wall surface of the transfer passage 63a, and forming a substantially rectangular cross section, and sandwiching the chamber 63b in the transfer direction of the glass substrate. And an exhaust passage 63c projecting upward from the upper wall surface of the transport passage 63a and having a substantially rectangular cross section. The exhaust passage portion 63c forms one exhaust passage together with the exhaust pipe 62 connected to the upper flange portion 63c '.

As shown in FIG. 1, a supply pipe 61 for supplying a raw material for forming an SiO ₂ film, for example, an alkoxysilane or the like, is connected to the chamber 63b. Further, a lid 66 for closing the upper end opening is detachably provided in the chamber portion 63b.

In the transport passage section 63a, the effective component of the raw material in a gaseous phase flows from the chamber section 63b to the upper surface of the glass substrate placed on the belt conveyor 50, and flows along the belt conveyor 50. The air flows in the horizontal direction and is discharged from the exhaust passage portion 63c toward the exhaust pipe 62.

The exhaust pipe 6 connected to the first film forming furnace 60
As shown in FIG. 1, in the lower region of FIG. 2, that is, in the exhaust pipe 62 near the flange 63 c ′ of the exhaust passage 63 c,
A pressure gauge 70 forming a part of a flow control means disposed so as to penetrate the wall and communicate with the inside, and an opening / closing valve as a part of a flow control means for controlling a flow rate of exhaust gas flowing through the exhaust pipe 62. 71 are provided. This pressure gauge 70
The exhaust pipe 62 in the area where the opening and closing valve 71 is provided
The passage area is narrowed as compared with the exhaust passage portion 63c of the muffle main body 63, and the downstream side thereof is connected to the collective exhaust pipe 62 '.

The pressure gauge 70 and the open / close valve 7
A heat insulating member 72 is provided on the outer peripheral wall of the exhaust pipe 62 so as to include the region where the first member 1 is provided. This heat insulating member 7
2 may be any material that does not lower the temperature of the exhaust gas flowing inside the exhaust pipe 62 as much as possible and maintains the temperature at around 500 ° C. For example, a fiber-based heat insulating material such as glass wool or rock wool is used. Can be.

By providing such a heat insulating member 72, heat radiation from the wall of the exhaust pipe 62 is blocked, and the exhaust pipe 6
The temperature of the exhaust flowing through the inside of the fuel cell 2 is prevented from lowering. as a result,
The active ingredient in a gaseous state that can be a film, that is, SiO ₂
The adhesion of particles and the like to the inner wall surface of the exhaust pipe 62 is prevented or suppressed.

In particular, the SiO ₂ particles and the like do not adhere to the inner wall surface of the exhaust pipe 62 in the area where the pressure gauge 70 and the opening / closing valve 71 as the flow rate adjusting means are provided, or the adhesion is suppressed. As a result, the desired functions of the pressure gauge 70 and the opening / closing valve 71 are maintained for a long time.

In this embodiment, the heat insulating member 7
2 is provided in the area where the pressure gauge 70 and the opening / closing valve 71 are arranged, but is not limited to this area.
May be provided on the outer wall surface of the exhaust passage portion 63c that forms By providing it also in this region, it is possible to prevent or suppress a decrease in the temperature of exhaust gas upstream of the position where the pressure gauge 70 and the on-off valve 71 are arranged.

The second film forming furnace 80 is provided downstream of the first film forming furnace 60 and, as shown in FIG. 2, surrounds the upper surface of the belt conveyor 50 and defines a muffle for defining a film forming space. The muffle main body 83 has a substantially rectangular cross section conveying passage 83a which extends in the horizontal direction and surrounds the belt conveyor 50 on which the glass substrate is placed.
A chamber portion 83b projecting upward from the upper wall surface of the transfer passage portion 83a and having a substantially rectangular cross section; and a chamber portion 83b disposed above the transfer passage portion 83a and arranged so as to sandwich the chamber portion 83b in the glass substrate transfer direction. Exhaust passage 83 projecting upward from the wall surface and having a substantially rectangular cross section
c. This exhaust passage 83c is
Exhaust pipe 82 connected to this upper end flange 83c '
Together form one exhaust passage.

As shown in FIG. 2, a raw material for forming an ITO film, for example, InCl ₃
A supply pipe 81 for supplying a solution obtained by adding SnCl ₄ to a CH ₃ OH solution of the present invention is connected. In addition, a lid 86 that covers the upper end opening of the chamber 83b is detachably provided. In the transport passage section 83a, the active ingredient of the raw material in a gaseous phase flows from the chamber section 83b to the upper surface of the glass substrate placed on the belt conveyor 50, and flows horizontally along the belt conveyor 50, The exhaust gas is discharged from the exhaust passage 83c toward the exhaust pipe 82.

The exhaust pipe 8 connected to the second film forming furnace 80
As shown in FIG. 2, in the lower region of FIG. 2, that is, in the exhaust pipe 82 near the flange portion 83c ′ of the exhaust passage portion 83c,
A pressure gauge 90 forming a part of a flow control means disposed so as to penetrate the wall surface and communicate with the inside, and an opening / closing valve as a part of a flow control means for controlling a flow rate of exhaust gas flowing through an exhaust pipe 82. 91 are provided. This pressure gauge 90
The exhaust pipe 82 in the area where the opening and closing valve 91 is provided
The passage area is narrowed as compared with the exhaust passage section 83c of the muffle main body 83, and the downstream side thereof is connected to the collective exhaust pipe 82 '.

The pressure gauge 90 and the open / close valve 9
A heat insulating member 92 is provided on the outer peripheral wall of the exhaust pipe 82 so as to include the region where the first member 1 is provided. This heat insulating member 9
2 may be any material that does not lower the temperature of the exhaust gas flowing inside the exhaust pipe 82 as much as possible and maintains the temperature at around 500 ° C., for example, using a fiber-based heat insulating material such as glass wool or rock wool. Can be.

In the second film forming furnace 80 for forming an ITO film, the adhesion and clogging in the exhaust pipe are not so much a problem as compared with the first film forming furnace 60 for forming an SiO ₂ film. It is not necessary to provide a simple heat insulating member 92, but by providing such a heat insulating member 92, the exhaust pipe 82
Of the exhaust gas flowing through the exhaust pipe 82 is prevented from lowering. As a result, the adhesion of the gaseous state effective component or the like that can become a film to the inner wall surface of the exhaust pipe 82 is more reliably prevented or suppressed. As a result, the intended functions of the pressure gauge 90 and the opening / closing valve 91, which are flow rate adjusting means, are surely maintained for a longer period of time.

In this embodiment, the heat insulating member 9
2 is provided in the area where the pressure gauge 90 and the opening / closing valve 91 are arranged, but is not limited to this area.
May be provided on the outer wall surface of the exhaust passage portion 83c that forms By providing it also in this region, it is possible to more reliably prevent or suppress a decrease in the temperature of exhaust gas on the upstream side of the position where the pressure gauge 90 and the opening / closing valve 91 are arranged.

FIGS. 3 and 4 are sectional views showing another embodiment of the film forming apparatus according to the present invention. In the film forming apparatus according to this embodiment, the heat insulating member 72 in the above-described embodiment,
Instead of 92, heaters 100 and 11 as heating means
It is the same as the previous embodiment except that 0 was adopted. Therefore, description of the same configuration as that of the above-described embodiment will be omitted.

That is, in this embodiment, as shown in FIG. 3, a heating means is provided on the outer peripheral wall of the exhaust pipe 62 so as to include a region where the pressure gauge 70 and the opening / closing valve 71 are provided. Electric heater 100 as
Is provided. The heater 100 does not lower the temperature of the exhaust gas flowing inside the exhaust pipe 62 as much as
What is necessary is just to maintain the temperature before and after. Particularly, if the heating temperature can be variably adjusted, it is preferable because the desired heating temperature can be appropriately set.

By providing such a heater 100,
Heating the outer wall surface of the exhaust pipe 62 to a desired temperature,
The exhaust gas flowing through the pipe 62 can be adjusted to a desired temperature.
Wear. Therefore, the active ingredient in a gas phase state that can be a film,
That is, SiO_TwoParticles adhere to the inner wall surface of the exhaust pipe 62
By heating to a temperature that does not cause
Clogging can be prevented. This allows, among other things,
A pressure gauge 70 and an opening / closing valve 71 as joint means are provided.
The inner wall surface of the exhaust pipe 62 in the _TwoParticles
Does not adhere or adhesion is suppressed. Accordingly
The expected functions of the pressure gauge 70 and the opening / closing valve 71 are long
Will be maintained over time.

In this embodiment, the heater 10
0 is provided in the area where the pressure gauge 70 and the opening / closing valve 71 are arranged, but is not limited to this area.
May be provided on the outer wall surface of the exhaust passage portion 63c that forms By providing it in this region, the temperature of the exhaust gas can be adjusted to a desired temperature even on the upstream side of the position where the pressure gauge 70 and the opening / closing valve 71 are arranged.

In the second film forming furnace 80, as shown in FIG. 4, a heater 110 as a heating means is provided on the outer peripheral wall of the exhaust pipe 82 so as to include a region where the pressure gauge 90 and the opening / closing valve 91 are provided. Is provided. This heater 1
Reference numeral 10 may be any as long as it does not lower the temperature of the exhaust gas flowing inside the exhaust pipe 82 as much as possible and maintains it at a temperature of about 500 ° C. In particular, as long as the heating temperature can be variably adjusted, This is preferable because a desired heating temperature can be set.

When a film is formed using a raw material having a boiling point higher than that of tetraalkoxylan, which is a raw material used for forming SiO ₂ , adhesion and clogging in the exhaust pipe do not cause much problems. It is not necessary to provide the heater 110. However, by providing such a heater 110, heat radiation from the wall surface of the exhaust pipe 82 can be cut off, and the temperature of exhaust flowing through the exhaust pipe 82 can be prevented from lowering. The temperature of the exhaust gas flowing through the exhaust pipe 82 can be adjusted to a desired temperature.

As a result, the adhesion of the gaseous state effective component or the like which can be a film to the inner wall surface of the exhaust pipe 82 is more reliably prevented or suppressed. As a result, the intended functions of the pressure gauge 90 and the opening / closing valve 91, which are flow rate adjusting means, are surely maintained for a longer period of time.

In this embodiment, the heater 11
0 is provided in the area where the pressure gauge 90 and the opening / closing valve 91 are arranged, but is not limited to this area.
May be provided on the outer wall surface of the exhaust passage portion 83c that forms By providing it also in this region, the temperature of the exhaust gas can be adjusted to a desired temperature even on the upstream side of the position where the pressure gauge 90 and the opening / closing valve 91 are arranged.

In the above embodiment, the heat insulating member 72,
Although the heater 92 and the heaters 100 and 110 are separately provided, a configuration having both of them may be employed. In this case, the temperature of the exhaust gas can be adjusted efficiently. Further, in the above-described embodiment, a configuration in which a heat insulating member or a heating unit is provided in a film forming apparatus that continuously forms a film is described. However, the present invention is not limited to this. The heat insulating member or the heating means according to the present invention can be applied to the film forming apparatus described above.

[0040]

As described above, according to the film forming apparatus of the present invention, an exhaust passage for exhausting the inside of a film forming furnace for forming a film on the surface of a substrate by a chemical vapor deposition method is provided. By providing a heat insulating member or a heating means around the wall defining the exhaust passage, heat radiation from the wall of the exhaust passage can be blocked or the temperature of exhaust flowing through the exhaust passage can be adjusted to a desired temperature. .

Therefore, it is possible to prevent a decrease in the temperature of the exhaust gas flowing through the exhaust passage, and to form a gas-phase effective component that can form a film.
For example, it is possible to prevent or suppress SiO ₂ particles and the like from adhering to the inner wall surface of the exhaust passage. As a result, it is not necessary to perform the cleaning work as frequently as in the related art, and it is possible to improve the productivity of the film formation line while suppressing the occurrence rate of defective products such as pinholes.

Further, the heat insulating member or the heating means may be
By arranging in the vicinity of the area where the flow rate adjusting means such as a pressure gauge or an opening / closing valve is provided, clogging of the exhaust passage and the like can be prevented, and the expected function of the flow rate adjusting means can be maintained for a long time. .

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration in which a heat insulating member is provided in an exhaust pipe of a first film forming furnace for producing a SiO ₂ film.

FIG. 2 is a cross-sectional view showing a schematic configuration in which a heat insulating member is provided in an exhaust pipe of a second film forming furnace for forming an ITO film.

FIG. 3 is a cross-sectional view showing a schematic configuration in which a heating means is provided in an exhaust pipe of a first film forming furnace for forming an SiO ₂ film.

FIG. 4 is a cross-sectional view showing a schematic configuration in which a heating means is provided in an exhaust pipe of a second film forming furnace for forming an ITO film.

[Explanation of symbols]

 Reference numeral 60: First film forming furnace 61: Supply pipe (source supply passage) 62: Exhaust pipe (exhaust passage) 63: Muffle main body 63a: Transport passage 63b: Chamber 63c ... Exhaust passage section (exhaust passage) 70 ... Pressure gauge (flow rate adjusting means) 71 ... Open / close valve (flow rate adjusting means) 72 ... Heat insulation member 80 ... Second film forming furnace 81 ... · Supply pipe (raw material supply passage) 82 ··· Exhaust pipe (exhaust passage) 83 ··· Muffle main body 83a ··· Conveyance passage section 83b ··· Chamber section 83c ··· Exhaust passage section (exhaust passage) 90 · ..Pressure gauge (flow rate adjusting means) 91 ... open / close valve (flow rate adjusting means) 92 ... heater (heating means) 100 ... heat insulating member 110 ... heater (heating means)

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shigeo Yamada 12-8, Goi-minamikaigan, Ichihara-shi, Chiba F-term (reference) in Nippon Soda Co., Ltd. Chiba Plant 4K030 BA44 CA06 CA12 EA11 JA05 KA25 5F045 AA03 AB32 AD09 AE29 AF07 BB14 EF20 EG02

Claims (6)

[Claims] 1. A film forming furnace for defining a space for accommodating a substrate, a material supply passage for supplying a film material into the film forming furnace, and an exhaust passage for exhausting the inside of the film forming furnace. A film forming apparatus for forming a film on a surface of a substrate by a chemical vapor deposition method, wherein at least a region connected to the film forming furnace is provided around a wall defining the exhaust passage. And a heat insulating member. 2. The exhaust passage is provided with flow rate adjusting means for adjusting a flow rate of exhaust gas flowing through the exhaust passage, and the heat insulating member is arranged to include a region where the flow rate adjusting means is provided. 2. The method according to claim 1, wherein
A film forming apparatus as described in the above. 3. The film forming apparatus according to claim 2, wherein said flow rate adjusting means has at least a pressure gauge or an on-off valve. 4. A film forming furnace for defining a space for accommodating a substrate, a material supply passage for supplying a film material to the inside of the film forming furnace, and an exhaust passage for exhausting the inside of the film forming furnace. A film forming apparatus for forming a film on a surface of a substrate by a chemical vapor deposition method, wherein at least a region connected to the film forming furnace is provided around a wall defining the exhaust passage. And a heating means for heating exhaust gas flowing through the inside of the film forming apparatus. 5. The exhaust passage is provided with flow rate adjusting means for adjusting the flow rate of exhaust gas flowing inside the exhaust passage, and the heating means is arranged so as to include a region where the flow rate adjusting means is provided. 5. The method according to claim 4, wherein
A film forming apparatus as described in the above. 6. The film forming apparatus according to claim 5, wherein said flow rate adjusting means has a pressure gauge or an on-off valve.