JP2008280561A - Film deposition apparatus and film deposition method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film deposition apparatus and a film deposition method by which occurrence of a warp in a substrate can be suppressed. <P>SOLUTION: The film deposition apparatus is used for depositing a film on the substrate (25) by a vapor-phase film deposition method and characterized by being provided with a holding means (10) for holding the substrate (25) slidably in the surface direction of the substrate (25). In the film deposition apparatus, the substrate (25) is held slidably in the surface direction of the substrate (25) by the holding means (10). In this case, stress caused by the difference between thermal expansion coefficients of the substrate (25) and the film is dispersed by sliding of the substrate (25). Thereby, the warpage of the substrate (25) can be reduced. Consequently, occurrence of defects in the film can be suppressed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a film forming apparatus and a film forming method.

  A fuel cell is a device that generally obtains electric energy using hydrogen and oxygen as fuel. Since this fuel cell is excellent in terms of the environment and can realize high energy efficiency, it has been widely developed as a future energy supply system.

  Among the fuel cells, those using solid electrolytes include solid polymer fuel cells, solid oxide fuel cells, hydrogen separation membrane cells, and the like. Here, the hydrogen separation membrane battery is a fuel cell provided with a dense hydrogen separation membrane. The dense hydrogen separation membrane is a layer formed of a metal having hydrogen permeability and also functions as an anode. The hydrogen separation membrane battery has a structure in which an electrolyte membrane having proton conductivity is formed on the hydrogen separation membrane. Hydrogen supplied to the hydrogen separation membrane is converted into protons, moves through the proton-conducting electrolyte membrane, and combines with oxygen at the cathode to generate power.

  As a method for forming an electrolyte membrane on a hydrogen separation membrane, a method of forming an electrolyte membrane on a substrate made of a hydrogen separation membrane by a vapor deposition method is used (for example, see Patent Document 1).

JP 2005-302424 A

  Here, since the substance constituting the hydrogen separation membrane is different from the substance constituting the electrolyte membrane, a difference in thermal expansion coefficient occurs between the hydrogen separation membrane and the electrolyte membrane. In this case, the hydrogen separation membrane warps as the temperature changes. This may cause defects in the electrolyte membrane. As a result, a short circuit may occur between the hydrogen separation membrane and the electrode provided on the electrolyte membrane.

  The present invention has been made in view of the above problems, and an object thereof is to provide a film forming apparatus and a film forming method capable of suppressing the occurrence of warping of a substrate.

  A film forming apparatus according to the present invention is a film forming apparatus for forming a film on a substrate by a vapor phase film forming method, and includes a holding means for holding the substrate so as to be slidable in the surface direction of the substrate. It is what. According to the film forming apparatus of the present invention, the substrate is held by the holding means so as to be slidable in the surface direction of the substrate. In this case, the stress caused by the difference in thermal expansion coefficient between the substrate and the film is dispersed by the sliding of the substrate. Thereby, the warpage of the substrate is alleviated. As a result, the occurrence of defects in the film is suppressed.

  In the above configuration, the holding unit may hold the substrate by pressing the substrate in the thickness direction of the substrate. In the above configuration, the holding unit may hold the substrate by pressing the outer peripheral portion of the substrate in the thickness direction of the substrate. According to this configuration, it is possible to secure a wide region where a film is formed on the substrate.

  In the above configuration, a heating unit for heating the substrate may be further provided. According to this configuration, the substrate can be heated to the film formation temperature. In the above configuration, the substrate may be a hydrogen permeable membrane having hydrogen permeability, and the membrane may be an electrolyte membrane having proton conductivity. According to this structure, it can suppress that a defect arises in an electrolyte membrane. Thereby, a short circuit between the hydrogen separation membrane and the electrode provided on the electrolyte membrane can be suppressed.

  The film forming method according to the present invention includes a holding step of holding the substrate slidably in the surface direction of the substrate, and a film forming step of forming a film on the substrate by a vapor deposition method. To do. According to the film forming method of the present invention, the substrate is held by the holding means so as to be slidable in the surface direction of the substrate. In this case, the stress caused by the difference in thermal expansion coefficient between the substrate and the film is dispersed by the sliding of the substrate. Thereby, the warpage of the substrate is alleviated. As a result, the occurrence of defects in the film is suppressed.

  In the film forming method, the holding step may be performed after the film forming step. In the film forming method, the holding step may be a step of holding the substrate by pressing the substrate in the thickness direction of the substrate. In the film forming method, the holding step may be a step of holding the substrate by pressing the outer peripheral portion of the substrate in the thickness direction of the substrate. According to this film forming method, it is possible to secure a wide area for forming a film on the substrate.

  In the film forming method, the film forming process may include a heating process for heating the substrate. According to this film formation method, the substrate can be heated to the film formation temperature. In the film forming method, the substrate may be a hydrogen permeable membrane having hydrogen permeability, and the membrane may be an electrolyte membrane having proton conductivity. According to this film forming method, it is possible to suppress the occurrence of defects in the electrolyte membrane. Thereby, a short circuit between the hydrogen separation membrane and the electrode provided on the electrolyte membrane can be suppressed.

  ADVANTAGE OF THE INVENTION According to this invention, the film-forming apparatus and film-forming method which can suppress generation | occurrence | production of the curvature of a board | substrate can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described.

(First embodiment)
A film forming apparatus according to a first embodiment of the present invention will be described. A film forming apparatus 100 according to the first embodiment is a film forming apparatus that forms a film on a substrate by a vapor deposition method. The vapor deposition method is not particularly limited, and for example, a PVD method, a CVD method, or the like can be used.

  FIG. 1 is a schematic diagram showing the overall configuration of the film forming apparatus 100. As shown in FIG. 1, the film forming apparatus 100 has a structure in which a holding means 10 for holding a substrate, a heating means 20 for heating the substrate, and the like are arranged in the film forming chamber 5. As the film forming chamber 5, for example, a vacuum chamber or the like can be used.

  The holding unit 10 is a holding unit that holds the substrate slidably in the surface direction of the substrate. For example, as the holding unit 10, a holding unit that holds the substrate by pressing the substrate in the thickness direction of the substrate can be used.

  The heating means 20 is a means for heating the substrate to a predetermined temperature. By providing the heating means 20, the film can be formed after the substrate is heated to a predetermined temperature. As the heating means 20, for example, an electric heater or the like can be used.

  FIG. 2A and FIG. 2B are schematic views of the holding means 10. FIG. 2A is a schematic view of the state in which the substrate 25 is held by the holding means 10 as viewed from the surface on which the film of the substrate 25 is formed (hereinafter referred to as a film formation surface). FIG. 2B is a cross-sectional view taken along line AA in FIG.

  As shown in FIGS. 2A and 2B, the holding means 10 includes a support base 12 and a presser fitting 14. The support table 12 is a table that supports the substrate 25. The substrate 25 is installed on the support base 12. Although it does not specifically limit as the support stand 12, For example, stainless steel etc. can be used.

  The presser fitting 14 is made of, for example, a plate spring made of stainless steel, and is fixed to the support base 12. The pressing metal 14 holds the substrate 25 by applying pressure in the thickness direction of the substrate 25. In this case, the substrate 25 is slidable in the surface direction of the substrate 25 while being held by the presser fitting 14. Note that a plurality of pressing metal fittings 14 may be provided.

  Subsequently, the operation of the film forming apparatus 100 according to the present embodiment will be described. FIG. 3A to FIG. 3D are schematic views showing a process of forming a film 30 on the substrate 25 in a vapor phase using the holding unit 10 according to the film forming apparatus 100. The operation of the film formation apparatus 100 will be described with reference to FIGS.

  First, as shown in FIG. 3A, the substrate 25 is held by the holding means 10. The pressing metal 14 holds the substrate 25 by pressing the film forming surface of the substrate 25 in the thickness direction. Thereby, the substrate 25 is slidable in the surface direction of the substrate 25 while being held by the presser fitting 14. The holding means 10 preferably holds the substrate 25 by pressing the outer periphery of the substrate 25. This is because it is possible to secure a wide region where the film on the substrate 25 is formed.

  Although it does not specifically limit as the board | substrate 25, For example, the hydrogen separation membrane which has hydrogen permeability can be used. As the hydrogen separation membrane, for example, a metal such as Pd (palladium), V (vanadium), Ta (tantalum), Nb (niobium), or an alloy thereof can be used. In addition, a hydrogen separation membrane in which a film of Pd, Pd alloy or the like having hydrogen dissociation ability is formed on the surface of the two surfaces of the hydrogen permeable metal layer on which the electrolyte membrane is formed is used. May be. Although the film thickness of a hydrogen separation membrane is not specifically limited, For example, it is about 5 micrometers-100 micrometers. The hydrogen separation membrane may be a self-supporting membrane or may be supported by a porous base metal plate.

  Next, as shown in FIG. 3B, the substrate 25 is heated by the heating means 20. In the present embodiment, the substrate 25 is heated to the film formation temperature of the film 30 described later.

Next, as shown in FIG. 3C, the film 30 is formed on the substrate 25 by a vapor deposition method such as a PVD method. The membrane 30 is not particularly limited, but when the substrate 25 is a hydrogen separation membrane, an electrolyte membrane having proton conductivity can be used. The electrolyte membrane is not particularly limited as long as it is a proton conductive electrolyte. For example, a perovskite type electrolyte (SrZrInO ₃ or the like), a pyrochlore type electrolyte (Ln ₂ Zr ₂ O ₇ (Ln: La (lanthanum)), Nd (neodymium) , Sm (samarium), etc.)), monazite type rare earth orthophosphate electrolyte (LnPO ₄ (Ln: La, Pr (praseodymium), Nd, Sm, etc.))), xenitype type rare earth orthophosphate electrolyte (LnPO ₄ (Ln: La , Pr, Nd, Sm, etc.)), rare earth metaphosphate electrolyte (LnP ₃ O ₉ (Ln: La, Pr, Nd, Sm, etc.)), rare earth oxyphosphate electrolyte (Ln ₇ P ₃ O ₁₈ (Ln: La , Pr, Nd, Sm, etc.)) and the like can be used. The thickness of the electrolyte membrane is not particularly limited, but is about 1 μm, for example.

  Next, as shown in FIG. 3D, the substrate 25 is cooled while being held by the holding means 10. In this case, the substrate 25 contracts in the direction of the arrow in FIG. In the case where the substrate 25 is a hydrogen separation membrane and the membrane 30 is an electrolyte membrane, the hydrogen separation membrane-electrolyte membrane assembly is completed by the steps of FIGS. 3A to 3D.

  According to the film forming apparatus 100 according to the first embodiment, the substrate 25 is held by the holding unit 10 so as to be slidable in the surface direction of the substrate 25. In this case, the stress caused by the difference in thermal expansion coefficient between the substrate 25 and the film 30 is dispersed by the sliding of the substrate 25. Thereby, the warp of the substrate 25 is alleviated. As a result, the occurrence of defects in the film 30 is suppressed. When the membrane 30 is made of an electrolyte membrane, a short circuit between the hydrogen separation membrane and the electrode provided on the electrolyte membrane can be suppressed.

  The pressing force by the pressing metal 14 is appropriately selected according to the difference in thermal expansion coefficient between the substrate 25 and the film 30, the material of the substrate 25 and the film 30, the thickness of the substrate 25 and the film 30, and the like. Further, the configuration of the holding means 10 is not limited to the configuration shown in FIG. 2A as long as the substrate 25 can be slidably held in the surface direction of the substrate 25. Moreover, the board | substrate 25 does not need to be hold | maintained by the pressing metal fitting 14 in the process of Fig.3 (a)-FIG.3 (c). This is because, if the substrate 25 is held by the presser fitting 14 in the cooling step of FIG. 3D, the stress caused by the difference in thermal expansion coefficient between the substrate 25 and the film 30 can be dispersed.

(Second Embodiment)
Subsequently, a film forming apparatus 100a according to a second embodiment of the present invention will be described. The film forming apparatus 100a according to the second embodiment includes a holding unit 10a instead of the holding unit 10 according to the first embodiment. Since other configurations are the same as those of the film forming apparatus 100 according to the first embodiment, description thereof is omitted.

  4 (a) and 4 (b) are schematic views of the holding means 10a. FIG. 4A is a schematic view of the state in which the substrate 25 is held by the holding unit 10 a as viewed from the film formation surface side of the substrate 25. FIG. 4B is an enlarged schematic view of a C portion of the cross section taken along the line BB in FIG. As shown in FIGS. 4A and 4B, the holding means 10a includes a support base 12a and a bolt 14a. In the present embodiment, a substrate in which the through hole 22 is formed is used as the substrate 25.

  The support table 12 a is a table that supports the substrate 25. The board | substrate 25 is supported by the support stand 12a. Although it does not specifically limit as the support stand 12a, For example, stainless steel etc. can be used. As shown in FIG. 4B, a screw hole into which the bolt 14a is screwed is formed in the support base 12a. The diameter of the bolt 14 a is set smaller than the diameter of the through hole 22.

  The bolt 14 a is screwed into the screw hole of the holding means 10 a through the through hole 22. Thereby, pressure is applied in the thickness direction of the substrate 25, and the substrate 25 is held by the holding means 10a. The fastening force by the bolt 14 a is such that the substrate 25 can slide in the surface direction of the substrate 25. The substrate 25 may be provided with a plurality of through holes 22. In this case, a screw hole is formed in the support base 12a corresponding to the position of the through hole 22.

  Also in the film forming apparatus 100 a according to the second embodiment, the substrate 25 slides in the surface direction of the substrate 25 in the cooling process of the substrate 25. Thereby, the stress caused by the difference in thermal expansion coefficient between the substrate 25 and the film 30 is dispersed. Thereby, the warp of the substrate 25 is alleviated.

  The pressing force by the bolt 14a is appropriately selected according to the difference in thermal expansion coefficient between the substrate 25 and the film 30, the material of the substrate 25 and the film 30, the thickness of the substrate 25 and the film 30, and the like. In addition, the configuration of the holding unit 10a is not limited to the configuration illustrated in FIG. 4A as long as the substrate 25 can be slidably held in the surface direction of the substrate 25.

  Hereinafter, the film 30 was formed on the substrate 25 by the film forming apparatus according to the above embodiment, and the characteristics were examined.

(Example)
In Examples, a film was formed on a substrate by the PVD method using the film forming apparatus 100 according to the first embodiment. First, as a substrate, 17 mm square and 80 μm thick Pd were prepared. Next, a film made of SrZrInO ₃ having a film thickness of 2 μm was formed on the substrate using the film forming apparatus 100. The film forming temperature was 600 ° C. Next, the substrate and the film were cooled to room temperature while holding the substrate by the presser fitting 14. The thermal expansion coefficient of Pd is 12 × 10 ⁻⁶ / K. The thermal expansion coefficient of SrZrInO ₃ is 10 × 10 ⁻⁶ / K.

(Comparative example)
In the comparative example, a film was formed on the substrate by the PVD method, and the substrate and the film were cooled to room temperature while fixing the substrate to the support base. Other conditions are the same as in the example.

(analysis)
The amount of warpage of the hydrogen separation membrane-electrolyte membrane assembly according to Examples and Comparative Examples was measured. First, each hydrogen separation membrane-electrolyte membrane assembly is arranged on a smooth plane so that the convex portion is on the upper side. Next, the distance between the vertex of the convex portion and the plane was measured. This distance was defined as the amount of warpage. The amount of warpage of the hydrogen separation membrane-electrolyte membrane assembly according to the comparative example was 3.5 mm. In comparison with this, the amount of warpage of the hydrogen separation membrane-electrolyte membrane assembly according to the example was 1.0 mm. Thus, the amount of warpage could be greatly reduced by holding the substrate while sliding it in the surface direction of the substrate by the holding means.

It is a schematic diagram which shows the whole structure of the film-forming apparatus which concerns on the 1st Embodiment of this invention. It is a schematic diagram of the holding means which concerns on the 1st Embodiment of this invention. It is a schematic diagram which shows the effect of the film-forming apparatus which concerns on 1st Embodiment. It is a schematic diagram of the holding means concerning the film-forming apparatus which concerns on 2nd Embodiment.

Explanation of symbols

Reference Signs List 5 Deposition chamber 10 Holding means 12 Support base 14 Press fitting 20 Heating means 22 Through hole 25 Substrate 30 Film

Claims (11)

A film forming apparatus for forming a film on a substrate by a vapor deposition method,
A film forming apparatus comprising: holding means for holding the substrate slidably in a surface direction of the substrate. The film forming apparatus according to claim 1, wherein the holding unit holds the substrate by pressing the substrate in a thickness direction of the substrate. The film forming apparatus according to claim 1, wherein the holding unit holds the substrate by pressing the outer peripheral portion of the substrate in the thickness direction of the substrate. The film forming apparatus according to claim 1, further comprising a heating unit that heats the substrate. The substrate is a hydrogen separation membrane having hydrogen permeability,
The film forming apparatus according to claim 1, wherein the membrane is an electrolyte membrane having proton conductivity. Holding the substrate slidably in the surface direction of the substrate;
And a film forming step of forming a film on the substrate by a vapor phase film forming method. The film forming method according to claim 6, wherein the holding step is performed after the film forming step. The film forming method according to claim 6, wherein the holding step is a step of holding the substrate by pressing the substrate in a thickness direction of the substrate. The film forming method according to claim 6, wherein the holding step is a step of holding the substrate by pressing the outer peripheral portion of the substrate in the thickness direction of the substrate. The film forming method according to claim 6, wherein the film forming step includes a heating step of heating the substrate. The substrate is a hydrogen separation membrane having hydrogen permeability,
The film forming method according to claim 6, wherein the membrane is an electrolyte membrane having proton conductivity.

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