JP5144231B2 - Deposition equipment - Google Patents

Description

  The present invention relates to a film forming apparatus.

In the manufacturing technology of a large FPD (Flat Panel Display), a chemical vapor deposition (CVD) method in which a thin film is formed on a glass substrate by using a chemical reaction of a film forming gas is used. Yes.

  As the CVD method, a thermal CVD method in which a chemical reaction is advanced on a substrate surface heated to a high temperature and a plasma CVD method in which a chemical reaction is advanced by plasma generated in a reaction vessel are known. The thermal CVD method and the plasma CVD method each have a problem that the substrate and the base film are liable to be electrically and thermally damaged because the substrate is exposed to a plasma space or the substrate is heated to a high temperature. . In addition, these CVD methods require high uniformity in plasma density and substrate temperature in order to obtain uniformity in film thickness and film quality, and thus it is difficult to cope with an increase in substrate size. Therefore, in the CVD technique, in order to solve the above-described problem, a catalytic CVD method in which a film forming gas is brought into contact with a heated catalyst wire such as tungsten to decompose the film forming gas into film forming species has attracted attention.

  Catalytic CVD, which uses catalytic action for the film-forming reaction, does not require plasma irradiation or high-temperature heating of the substrate because the surface of the catalyst wire is responsible for the progress of the chemical reaction. And thermal damage can be greatly suppressed. In addition, since the catalytic CVD method can expand the reaction system simply by increasing the number of catalyst wires, it can relatively easily cope with an increase in the size of the substrate.

In the catalytic CVD method, the distance between the catalyst wire and the main surface of the substrate is an element that defines the amount of film forming species supplied to the substrate, and thus greatly affects the film forming speed and film thickness uniformity. For example, when the substrate main surface approaches the catalyst line, the deposition rate increases, and when the distance between the substrate main surface and the catalyst line becomes uniform, the film thickness distribution becomes uniform. In Patent Document 1, in order to improve the film forming speed and film thickness uniformity, the surface direction of the substrate main surface and the vertical direction are arranged in parallel, and the U-shaped catalyst wire is arranged along the vertical direction, that is, the substrate. Suspend along the main surface. According to this, since the deflection due to the thermal expansion of the catalyst wire and the extension of the catalyst wire is greatly reduced, even when the substrate main surface is brought close to the catalyst wire, the space between the substrate main surface and the catalyst wire is The distance can be made uniform.
Japanese Patent No. 2000-303182

  When the film formation process is continuously performed using the CVD method, the chemical reaction of the film formation gas is repeated in the film formation chamber, so that the film formation species remaining after each film formation process is deposited inside the film formation chamber. Will continue to do. The film-forming residue deposited in the film-forming chamber is particularly deposited in the vicinity of the injection nozzle for injecting the film-forming gas, which causes the injection nozzle to be clogged and causes the film-forming gas supply amount to fluctuate. These problems can be caused by cleaning the spray nozzle by periodically removing it from the deposition chamber, or by supplying activated species of a cleaning gas such as halogen into the deposition chamber to chemically remove the deposition residue. It is thought that it can be solved by carrying out regularly.

However, when removing the spray nozzle, the film forming chamber is once exposed to the atmosphere, so that a great amount of maintenance time is required to reproduce the film forming environment. Further, when cleaning is performed, the catalyst wire used in the catalytic CVD method reacts with the cleaning gas to generate a volatile compound, which causes problems such as unstable heating temperature and disconnection. Therefore, in a film forming apparatus using the catalytic CVD method, it is difficult to frequently perform replacement of the injection nozzle and cleaning of the film forming chamber.

  The present invention has been made to solve the above problems, and an object of the present invention is to provide a film forming apparatus that stabilizes the supply state of a film forming gas in a film forming process using a catalyst wire.

  The film forming apparatus according to claim 1 is a film forming apparatus for forming a thin film on a substrate, wherein a pair of substrates are held in a standing state and each substrate is opposed to each other, and a gap between each substrate A plurality of catalyst wires disposed, and a gas supply unit configured to supply a film forming gas to the gap, the gas supply unit being disposed outside the gap along the surface direction of the substrate. The gist of the invention is to have a supply nozzle that extends and a shielding plate that surrounds the opening of the supply nozzle.

  In the film forming apparatus according to the first aspect, since the film forming species scattered from the gap toward the opening collide with the shielding plate, the deposition amount of the film forming residue in the opening can be reduced. Therefore, this film forming apparatus can stabilize the supply state of the film forming gas in the film forming process using the catalyst wire.

  The film forming apparatus according to claim 2 is the film forming apparatus according to claim 1, wherein the supply nozzle is arranged from the outside of the gap toward the gap, and the shielding plate is the opening. It extends from the surface toward the gap along the surface direction.

  In the film forming apparatus according to claim 2, since the film forming gas from the supply nozzle flows along the surface direction of the substrate, the contact between the film forming gas and the catalyst wire can be effectively realized. The film forming gas can be used effectively.

  The film forming apparatus according to claim 3 is the film forming apparatus according to claim 1 or 2, wherein the supply nozzle is arranged from the outside of the gap toward the gap, and the shielding plate is The gist is that it is disposed on the side of the gap as viewed from the opening.

In the film forming apparatus according to the third aspect, since the shielding plate surrounds the gap side of the opening, the deposition amount of the film forming residue in the opening can be further reduced.
The film forming apparatus according to claim 4 is the film forming apparatus according to claim 1, wherein the supply nozzle is disposed toward the outside of the gap, and the shielding plate is viewed from the opening. The gist is to be disposed on the opposite side of the gap.

  In the film forming apparatus according to the fourth aspect, since the opening of the nozzle faces the outside of the gap, the deposition amount of the film forming residue in the opening can be more reliably reduced. Further, since the film forming gas supplied toward the outside of the gap collides with the shielding plate and is then supplied to the gap, the use efficiency of the film forming gas is not impaired.

A film forming apparatus according to a fifth aspect is the film forming apparatus according to any one of the first to fourth aspects, wherein the shielding plate is disposed outside the gap.
In the film forming apparatus according to the fifth aspect, since the shielding plate does not enter the gap, the film forming species from the catalyst wire can be scattered more smoothly onto the substrate. Therefore, this film forming apparatus can stabilize the supply state of the film forming gas without impairing the film thickness uniformity of the thin film.

A film forming apparatus according to a sixth aspect of the present invention is the film forming apparatus according to any one of the first to fifth aspects, further including a pressure reducing unit that makes the pressure of the gap 10 Pa or less.
Since the film forming apparatus according to claim 6 performs the film forming process in the pressure region of the molecular flow, the film forming gas flow fluctuation caused by the shielding plate affects the concentration distribution of the film forming species, that is, The influence on the film thickness distribution of the thin film can be suppressed. Therefore, this film forming apparatus can improve the degree of freedom in designing the shielding plate.

  As described above, according to the present invention, there is provided a film forming apparatus that stabilizes a supply state of a film forming gas in a film forming process using a catalyst wire.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a view of a catalytic CVD apparatus 10 as a film forming apparatus viewed from the vertical direction. In FIG. 1, a catalytic CVD apparatus 10 is an in-line type in which a carry-in chamber 11, a first film formation chamber 12, a second film formation chamber 13, and a carry-out chamber 14 are sequentially connected via a gate valve GV. A film forming apparatus.

  The carry-in chamber 11 is a vacuum chamber connected to the exhaust line P, receives the substrate S from the outside, and carries it into the catalytic CVD apparatus 10. Inside the loading chamber 11, a pair of loading stages 11 </ b> S for supporting the substrate S is disposed. The pair of carry-in stages 11 </ b> S line up the pair of substrates S carried into the carry-in chamber 11 so as to face each other, and transfer the pair of substrates S to the first film forming chamber 12. In the present embodiment, the transport direction of the substrate S is referred to as + X direction, the normal direction of the substrate S is referred to as + Y direction, and the upper vertical direction is referred to as + Z direction.

  The first film formation chamber 12 is a vacuum chamber connected to the carry-in chamber 11 via the gate valve GV, and communicates with the carry-in chamber 11 when the gate valve GV is opened. The first film formation chamber 12 is connected to the exhaust line P and is decompressed to a low pressure of 10 Pa or less, and performs the film formation process in the region of the molecular flow. Inside the first film forming chamber 12, a pair of first stages 12S for supporting the substrate S is disposed. The pair of first stages 12 </ b> S continuously line up the substrates S from the carry-in chamber 11 to raise the temperature to a predetermined temperature, and transfer the pair of substrates S to the second film forming chamber 13. Each exhaust line P exhausts isotropically the space between the pair of substrates S arranged in a row from the back side of each substrate S to the main surface of the substrate S.

  The second film forming chamber 13 is a vacuum tank connected to the first film forming chamber 12 via the gate valve GV, and communicates with the second film forming chamber 13 when the gate valve GV is opened. The second film forming chamber 13 is connected to the exhaust line P and is decompressed to a low pressure of 10 Pa or less, and performs the film forming process in the region of the molecular flow. Inside the second film forming chamber 13, a pair of second stages 13 </ b> S for supporting the substrate S are disposed. The pair of second stages 13 </ b> S continuously line up the substrates S from the first film formation chamber 12 to raise the temperature to a predetermined temperature, and transfer the pair of substrates S to the carry-out chamber 14. Each exhaust line P exhausts isotropically the space between the pair of substrates S arranged in a row from the back side of each substrate S to the main surface of the substrate S.

  The carry-out chamber 14 is a vacuum chamber connected to the exhaust line P, and carries the substrate S from the second film formation chamber 13 to the outside. A pair of unloading stages 14 </ b> S for supporting the substrate S is disposed inside the unloading chamber 14. The pair of unloading stages 14 </ b> S tilt the main surfaces of the pair of substrates S loaded into the unloading chamber 14 in the horizontal direction, and unload the pair of substrates S to the outside.

  Inside the first film formation chamber 12, between the pair of first stages 12S, a plurality of catalyst wires 15 extending in the vertical direction are arranged along the transport direction of the substrate S, that is, the + X direction. . Similarly, a plurality of catalyst wires 15 extending in the vertical direction are arranged along the + X direction inside the second film forming chamber 13 and between the pair of second stages 13S.

Each catalyst wire 15 is a wire made of tungsten, tantalum, molybdenum, or the like, and is suspended between a pair of substrates S arranged in a line. Each catalyst line 15 is connected to a power source (not shown) and heated to a predetermined temperature to activate the film forming gas. Each catalyst line 15 diffuses the activated film forming gas isotropically. In the present embodiment, a space between the pair of substrates S arranged in a row and including the catalyst wires 15 is referred to as a reaction space.

  A gas supply unit 20 is disposed between the catalyst wire 15 and each substrate S, which is a reaction space in the first film formation chamber 12 and the second film formation chamber 13. 2A is a plan view showing the position of the gas supply unit 20, and FIG. 2B is a cross-sectional view taken along line AA in FIG. 3 is a perspective view showing a gas supply unit, and FIG. 4 is an end view showing a main part of the gas supply unit 20. As shown in FIG.

  In FIG. 2A, the plurality of gas supply units 20 are disposed at positions corresponding to the sides of the substrate S so as to surround the outer periphery of the substrate S, respectively. Each gas supply unit 20 includes a pipe 21 that extends along one side of the substrate S, and an adhesion preventing member 22 that is attached to the substrate S side of the pipe 21 and extends along one side of the substrate S.

Each pipe 21 is a pipe formed with a longitudinal direction of 1.5 m, for example, and is connected to a gas line of a facility where the catalytic CVD apparatus 10 is installed, and the film forming gas from the gas line is supplied to the inside of the pipe. To introduce. Note that when a silicon film is formed as a film formation process, silane (SiH ₄ ) and hydrogen (H ₂ ) can be used as a film formation gas. When a silicon nitride film is formed, silane and ammonia are used. (NH ₃ ) can be used. In the case of forming a silicon oxynitride film, silane and nitrous oxide (N ₂ O) can be used as a deposition gas.

  In FIG. 2B, a plurality of holes (hereinafter simply referred to as lead-out holes N) extending toward the reaction space are arranged at equal intervals along one side of the substrate S in each pipe 21. . Each lead-out hole N is a circular hole having a diameter of 1 mm, for example, and is arranged at a pitch of 10 mm along the longitudinal direction of the pipe 21. Each lead-out hole N guides the film forming gas introduced into the pipe 21 to the outside by dispersing it along the longitudinal direction of the pipe 21.

  Each adhesion preventing member 22 is formed with a through hole (hereinafter simply referred to as an injection hole N1) extending from each lead-out hole N toward the reaction space at a position corresponding to each lead-out hole N. Each injection hole N1 is formed along the surface direction (XZ plane) of the substrate S, and the film formation gas led out from the pipe 21 is injected from the opening toward the reaction space. In the present embodiment, the supply nozzle is configured by the lead-out hole N and the injection hole N1 corresponding to the lead-out hole N.

  In FIG. 3, a pair of shielding pieces 22 a extending along the surface direction (XZ plane) of the substrate S are provided on the adhesion preventing member 22, respectively, in the arrangement direction of the injection holes N <b> 1, that is, in the longitudinal direction of the adhesion preventing member 22. It is formed over the entire width. The pair of shielding pieces 22a are each formed from the reaction space toward the respective injection holes N1 and formed from the catalyst wire 15 toward the respective injection holes N1, and from the substrate S to each injection. The film-forming seeds that scatter toward the hole N1 are shielded against each injection hole N1.

  In FIG. 4, the pair of shielding pieces 22 a has a film-forming species corresponding to each injection hole N <b> 1 by the thickness of the shielding piece 22 a (thickness in the + Z direction in FIG. 3: shielding thickness H). Since the incident angle θr is reduced, deposition of film forming species in each injection hole N1 can be suppressed. Further, since the pair of shielding pieces 22a forcibly directs the flight direction of the film forming gas injected from each of the injection holes N1 to the reaction space, the use efficiency of the film forming gas can be improved. The shielding thickness H of the pair of shielding pieces 22a is set based on the film thickness uniformity of the thin film formed on the substrate S, respectively.

That is, in the first film forming chamber 12 and the second film forming chamber 13, since the film forming process is executed in the pressure region of the molecular flow, when the film forming gas concentration in the reaction space is uniform, the catalyst line 15 The film-forming species that scatter from the upper point scatter substantially isotropically. Since the pair of shielding pieces 22a are located between the catalyst wire 15 and the substrate S, when the shielding thickness H is increased, the film is formed from the catalyst wire 15 on the outer edge of the main surface of the substrate S. Shields seed incidence. Therefore, in the present embodiment, the shielding thickness H of the pair of shielding pieces 22a is set to a thickness that does not overlap at least the substrate S when viewed from the normal direction (+ Y direction) of the substrate S. According to this, since the film forming species sufficiently enters at the outer edge of the substrate S, it is possible to ensure the film thickness uniformity of the thin film formed on the substrate S.

According to the first embodiment, the following effects can be obtained.
(1) In the first embodiment, the gas supply unit 20 is disposed outside the gap between the pair of substrates S, that is, outside the reaction space, and extends along the surface direction of the substrate S. And a shielding piece 22a surrounding the opening of the injection hole N1. Therefore, the catalytic CVD apparatus 10 can reduce the deposition amount of the film forming residue in the opening because the film forming species scattered from the gap between the pair of substrates S toward the opening collide with the shielding piece 22a. As a result, the catalytic CVD apparatus 10 can stabilize the supply state of the film forming gas in the film forming process using the catalyst wire 15.

  (2) In the first embodiment, the injection hole N1 is disposed from the outside of the reaction space toward the reaction space, and the shielding piece 22a faces the surface of the substrate S from the opening of the injection hole N1 toward the reaction space. A shape extending along the direction. Therefore, since the film forming gas from the injection hole N1 flows along the surface direction of the substrate S, the catalytic CVD apparatus 10 can effectively realize the contact between the film forming gas and the catalyst wire 15. The film forming gas can be used effectively.

  (3) In the first embodiment, the shielding piece 22a is disposed outside the reaction space. Therefore, in the catalytic CVD apparatus 10, since the shielding piece 22a does not enter the reaction space, the film formation species from the catalyst wire 15 can be more smoothly scattered onto the substrate S. As a result, the catalytic CVD apparatus 10 can stabilize the supply state of the film forming gas without impairing the film thickness uniformity of the thin film.

  (4) In said 1st embodiment, the exhaust line P makes the pressure of reaction space 10 Pa or less. Therefore, since the catalytic CVD apparatus 10 performs the film forming process in the pressure region of the molecular flow, the influence on the concentration distribution of the film forming species with respect to the flow fluctuation of the film forming gas caused by the shielding piece 22a, that is, the thin film The influence on the film thickness distribution can be suppressed. As a result, the catalytic CVD apparatus 10 can improve the degree of freedom regarding the design of the shape and size of the shielding piece 22a.

(Second embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings. In the second embodiment, the adhesion preventing member 22 of the first embodiment is changed. Therefore, in the following, the changes will be described in detail. FIG. 5 is a perspective view showing the adhesion preventing member 22 of the second embodiment.

  In FIG. 5, a plurality of injection holes N1 extending from each lead-out hole N toward the reaction space are formed in the adhesion preventing member 22 at positions corresponding to the respective lead-out holes N, and the reaction space side of each injection hole N1 is formed. A plurality of first shielding pieces 22b are formed in each (+ Z direction in FIG. 5). Each first shielding piece 22b has an inverted L-shaped cross section when viewed from the longitudinal direction of the deposition preventing member 22, and is formed so as to cover the reflection space side of each injection hole N1. A second shielding piece 22c extending along the surface direction (XZ plane) of the substrate S is formed on the deposition preventing member 22 over substantially the entire width in the arrangement direction of the injection holes N1, that is, the longitudinal direction of the deposition preventing member 22. Yes.

Each of the first shielding pieces 22b and one second shielding piece 22c cooperate to each other, and among the film-forming species that scatter from the reaction space toward the respective injection holes N1, the components that scatter along the YZ plane. The film type is shielded against each injection hole N1. The thickness of each first shielding piece 22b is formed by the shielding thickness H in the first embodiment, and is set so that the film-forming species can be sufficiently incident also on the outer edge of the main surface of the substrate S. .

  Since the film forming process is performed in the molecular flow pressure region, the distribution of the film forming gas in the reaction space is such that the reaction space side of each injection hole N1 is covered with the first shielding piece 22b and the second shielding piece 22c. The uniformity can be obtained regardless of whether

According to the second embodiment, the following effects can be obtained.
(5) In the second embodiment, the injection hole N1 is disposed from the outside of the reaction space toward the reaction space, and the first shielding piece 22b is viewed from the opening of the injection hole N1, and the reaction space of the opening. It is arranged on the side. Therefore, since the first shielding piece 22b surrounds the reaction space side of the injection hole N1, the catalytic CVD apparatus 10 can further reduce the deposition amount of the film formation residue at the opening of the injection hole N1. As a result, the catalytic CVD apparatus can further stabilize the supply state of the film forming gas in the film forming process using the catalyst wire 15.

(Third embodiment)
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings. The third embodiment is a modification of the gas supply unit 20 of the first embodiment. Therefore, in the following, the changes will be described in detail. FIG. 6 is an end view showing a main part of the gas supply unit 20 of the third embodiment.

  In FIG. 6, the piping 21 has a plurality of supply holes N as supply nozzles extending toward the outside of the reaction space, arranged at equal intervals along one side of the substrate S. Each lead-out hole N is a circular hole having a hole diameter of 1 mm, for example, as in the first embodiment or the second embodiment, and is arranged at a pitch of 10 mm along the longitudinal direction of the pipe 21. Each lead-out hole N distributes the film forming gas introduced into the pipe 21 along the longitudinal direction of the pipe 21 and guides it toward the outside of the reaction space (the lower side in FIG. 6).

  The adhesion preventing member 22 as a shielding plate is formed in a box shape with the reaction space side opened, and the piping 21 is accommodated therein. Each adhesion preventing member 22 receives the film forming gas led out of the reaction space from the pipe 21 and supplies it to the reaction space. Each of the deposition preventing members 22 shields all of the film forming species scattered from the reaction space toward each of the outlet holes N against each of the outlet holes N. In addition, each adhesion prevention member 22 is formed in the size which does not overlap at least the board | substrate S seeing from the normal line direction (+ Y direction) of the board | substrate S similarly to 1st embodiment and 2nd embodiment.

  In addition, since the film forming process is executed in the pressure region of the molecular flow, the distribution of the film forming gas in the reaction space is uniform regardless of whether the lead-out direction of each lead-out hole N is covered with the deposition preventing member 22. Can be obtained.

According to the third embodiment, the following effects can be obtained.
(6) In the third embodiment, the outlet hole N is disposed toward the outside of the reaction space, and the adhesion preventing member 22 is disposed on the opposite side of the reaction space when viewed from the opening of the outlet hole N. The Therefore, since the opening of the outlet hole N faces the outside of the reaction space, the catalytic CVD apparatus 10 can reliably reduce the deposition amount of the film forming residue at the opening of the outlet hole N. Further, since the film forming gas supplied toward the outside of the outlet hole N collides with the deposition preventing member 22 and is then supplied to the reaction space, the catalytic CVD apparatus 10 impairs the use efficiency of the film forming gas. There is nothing. In addition, you may implement the said embodiment in the following aspects.

-Although the shielding piece 22a and the 2nd shielding piece 22c of the said embodiment are respectively the structures common to each injection hole N1, not only this but the structure formed for every injection hole N1 may be sufficient. Moreover, although the 1st shielding piece 22b is the structure formed for every injection hole N1, not only this but the structure common to each injection hole N1 may be sufficient.

  -The catalytic CVD apparatus 10 of the said embodiment may be the film-forming apparatus for manufacturing a photoelectric conversion apparatus.

The figure which shows a catalytic CVD apparatus typically. (A), (b) is the top view and end view which respectively show the inside of the film-forming chamber. The perspective view which shows the gas supply part of 1st embodiment. The principal part end view which shows the gas supply part of 1st embodiment. The perspective view which shows the gas supply part of 2nd embodiment. The principal part end view which shows the gas supply part of 3rd embodiment.

Explanation of symbols

  P ... exhaust line as decompression means, S ... substrate, 10 ... catalytic CVD apparatus as film forming device, 12 ... first film forming chamber, 12S ... first stage constituting stage, 13 ... second film forming chamber, DESCRIPTION OF SYMBOLS 13 ... 2nd stage which comprises a stage, 15 ... Catalyst wire, 20 ... Gas supply part, 21 ... Piping, 22 ... Adhesion member, 22a ... Shielding piece as a shielding board, 22b ... First shielding piece as a shielding board 22c: second shielding pieces as shielding plates, N: outlet holes, N1: injection holes.

Claims (6)

A film forming apparatus for forming a thin film on a substrate,
A stage that holds a pair of substrates in an upright state and faces each substrate;
A plurality of catalyst wires disposed in the gap between the substrates;
A gas supply unit for supplying a film forming gas to the gap,
The gas supply unit
A supply nozzle disposed outside the gap and extending along a surface direction of the substrate;
And a shielding plate surrounding the opening of the supply nozzle. The film forming apparatus according to claim 1,
The supply nozzle is disposed from the outside of the gap toward the gap;
The film forming apparatus, wherein the shielding plate extends along the surface direction from the opening toward the gap. The film forming apparatus according to claim 1 or 2,
The supply nozzle is disposed from the outside of the gap toward the gap;
The film forming apparatus, wherein the shielding plate is disposed on the gap side when viewed from the opening. The film forming apparatus according to claim 1,
The supply nozzle is disposed toward the outside of the gap;
The film forming apparatus, wherein the shielding plate is disposed on the opposite side of the gap as viewed from the opening. It is the film-forming apparatus as described in any one of Claims 1-4,
The film forming apparatus, wherein the shielding plate is disposed outside the gap. It is the film-forming apparatus as described in any one of Claims 1-5,
A film forming apparatus having a pressure reducing means for reducing the pressure of the gap to 10 Pa or less.

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