Ozone gas generating discharge cell and method for manufacturing the same.

Abstract

In a discharge cell that generates ozone gas, the generation of particles that become impurities is suppressed. [Solution] The discharge cell (24) that generates ozone gas by silent discharge according to the present disclosure comprises a pair of opposing electrodes (31), at least one dielectric (32) disposed between the pair of opposing electrodes (31), a discharge void (G) formed between the electrodes (31) and the dielectric (32), or between a pair of dielectrics (32), through which oxygen gas passes, and a functional film (33) that covers the surface of the dielectric (32) on the discharge void (G) side and suppresses the peeling of the discharge cell due to the silent discharge. The functional film (33) consists of only amorphous components on at least the surface on the discharge void side.

Description

Technical Field

[0007] ,

[0001] The present invention relates to a discharge cell for generating ozone gas and a method for manufacturing the same.

Background Art

[0002] An ozone gas generator that generates ozone gas using oxygen gas as a raw material is widely used in semiconductor manufacturing processes and the like.

[0003] Patent Document 1 discloses an ozone gas generator having a silent discharge type discharge cell. In the discharge cell, dielectrics are laminated inside a pair of electrodes connected to a power source. When a voltage is applied from the power source to the pair of electrodes, silent discharge occurs in the discharge gap between the dielectrics, and ozone gas is generated. In Patent Document 1, a functional film is formed on the surface of the dielectric on the discharge gap side to improve performance.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When ozone gas is used in the manufacture of semiconductor devices, particularly in the cleaning of silicon wafers, etc., depending on the purpose of use, it is particularly important to remove impurities contained in the generated ozone gas.

[0006] An object of the present disclosure is to suppress the generation of particles that become impurities in a discharge cell that generates ozone gas.

Means for Solving the Problems

[0007] The discharge cell of this disclosure is a discharge cell that generates ozone gas by silent discharge, and comprises a pair of opposing electrodes, at least one dielectric disposed between the pair of opposing electrodes, a discharge void formed between the electrodes and the dielectric, or between a pair of dielectrics, through which oxygen gas passes, and a functional film that covers the surface of the dielectric on the discharge void side and suppresses the peeling of the discharge cell by silent discharge. At least the surface of the functional film on the discharge void side consists only of amorphous components.

[0008] The ozone gas generator of this disclosure comprises the above-mentioned discharge cell and an oxygen supply source that supplies oxygen with a purity of 99.9% or higher to the discharge cell.

[0009] The method for manufacturing a discharge cell according to the present disclosure comprises the steps of forming a first material film on one surface of a dielectric by screen printing, and firing the first material film to form a functional film in which at least the surface on the discharge void side consists only of amorphous components and suppresses the peeling of the discharge cell due to the silent discharge. [Effects of the Invention]

[0010] According to this disclosure, it is possible to suppress the inclusion of particles as impurities in the generated ozone gas. [Brief explanation of the drawing]

[0011] [Figure 1] Figure 1 is a schematic diagram illustrating the ozone gas generator of the present disclosure. [Figure 2] Figure 2 is a schematic cross-sectional view showing the ozone gas generation unit of the present disclosure, particularly its discharge cell. [Figure 3] Figure 3 is a cross-sectional view corresponding to the line III-III in Figure 2. [Figure 4] Figure 4 is a cross-sectional view corresponding to the line IV-IV in Figure 3. [Figure 5] Figure 5 is a diagram illustrating the method for manufacturing the discharge cell of this disclosure. [Figure 6] Figure 6 is a schematic cross-sectional view showing a modified discharge cell of the present disclosure. [Modes for carrying out the invention]

[0012] The embodiments will be described below with reference to the drawings. The following description is illustrative and not limiting. Furthermore, modifications can be made as appropriate within the scope of achieving the desired effect.

[0013] --Ozone gas generator-- Figure 1 is a schematic diagram of the ozone gas generator (20) of the present disclosure. The ozone gas generator (20) comprises a raw material gas supply unit (21), an ozone gas generation unit (22), and an ozone gas extraction unit (23).

[0014] A raw material gas is supplied to the raw material gas supply unit (21). A supply pipe (not shown) is connected to the raw material gas supply unit (21). The raw material gas supply unit (21) is connected to a raw material gas supply source such as a gas cylinder via the supply pipe. High-purity oxygen gas (99.9% or higher) is used as the raw material gas. In the ozone gas generator (20) of this disclosure, it is preferable to add a certain amount of water (about 50 to 1000 ppm) to the raw material gas using a gas conditioner (not shown) in order to stably generate ozone gas.

[0015] The ozone gas generation unit (22) is supplied with raw material gas from the raw material gas supply unit (21). In the ozone gas generation unit (22), ozone gas is generated from oxygen gas through silent discharge. Details of the ozone gas generation unit (22) will be described later.

[0016] The ozone gas extraction unit (23) supplies the ozone gas generated in the ozone gas generation unit (22) to the outside. Extraction piping (not shown) is connected to the ozone gas extraction unit (23). The ozone gas extracted from the extraction piping is dissolved in, for example, pure water to produce ozonated water. This ozonated water is used, for example, to clean silicon wafers in semiconductor manufacturing equipment.

[0017] --Details of the ozone gas generation unit-- FIG. 2 is a cross-sectional view schematically showing the ozone gas generation unit (22). FIG. 3 is a cross-sectional view corresponding to line III-III in FIG. 2, and FIG. 2 is a cross-sectional view corresponding to line II-II in FIG. 3. Further, FIG. 4 is a cross-sectional view corresponding to line IV-IV in FIG. 3. However, all are schematic diagrams, and dimensions, ratios, etc. do not necessarily correspond, nor do they necessarily reflect the actual dimensions.

[0018] As shown in FIG. 2, the ozone gas generation unit (22) includes a silent discharge type discharge cell (24) and a power source (25) connected to the discharge cell (24). The discharge cell (24) has a high-pressure side electrode unit (30A) and a low-pressure side electrode unit (30B). Since the configurations of the high-pressure side electrode unit (30A) and the low-pressure side electrode unit (30B) are basically the same, they may be collectively referred to as the electrode unit (30). The discharge cell (24) includes at least one pair of such opposing electrode units (30).

[0019] As shown in FIGS. 3 and 4, the high-pressure side electrode unit (30A) and the low-pressure side electrode unit (30B) are insulated by an insulating partition member (40). A discharge gap (G) through which oxygen gas flows is formed between the high-pressure side electrode unit (30A) and the low-pressure side electrode unit (30B). The high-pressure side electrode unit (30A) is a high-pressure side electrode unit, and the low-pressure side electrode unit (30B) is a ground side (low-pressure side) electrode unit.

[0020] The power source (25) is constituted by a high-frequency high-voltage power source. The high-pressure side electrode unit (30A) has a high-pressure side electrode (31A), a high-pressure side dielectric (32A), and a high-pressure side functional film (33A), which are laminated in order in the thickness direction. The low-pressure side electrode unit (30B) has a low-pressure side electrode (31B), a low-pressure side dielectric (32B), and a low-pressure side functional film (33B), which are laminated in order in the thickness direction.

[0021] The high-voltage side electrode (31A) and the low-voltage side electrode (31B) are electrically connected to the power supply (25). The high-voltage side electrode (31A) and the low-voltage side electrode (31B) are formed in the shape of a plate or a film. The high-voltage side electrode (31A) and the low-voltage side electrode (31B) are positioned opposite each other with a discharge gap (G) in between.

[0022] The high-pressure side dielectric (32A) is formed on the discharge gap (G) side surface (lower surface in Figure 2) of the high-pressure side electrode (31A). The low-pressure side dielectric (32B) is formed on the discharge gap (G) side surface (upper surface in Figure 2) of the low-pressure side electrode (31B). The high-pressure side dielectric (32A) and the low-pressure side dielectric (32B) are formed in a plate shape. The high-pressure side dielectric (32A) and the low-pressure side dielectric (32B) are composed of an insulating material such as alumina. The high-pressure side dielectric (32A) may cover the high-pressure side electrode (31A). Similarly, the low-pressure side dielectric (32B) may cover the low-pressure side electrode (31B).

[0023] Furthermore, since the configurations of the high-pressure side dielectric (32A) and the low-pressure side dielectric (32B) are basically the same, they are sometimes collectively referred to as dielectric (32). Similarly, the high-pressure side electrode (31A) and the low-pressure side electrode (31B) are sometimes collectively referred to as electrode (31).

[0024] The dielectric (32) is formed in the shape of a rectangular plate. The dielectric (32) may be obtained by firing high-purity alumina. The thickness of the dielectric (32) is preferably 0.05 to 0.9 mm.

[0025] A pair of opposing side edges of the dielectric (32) (the upper and lower side edges in Figure 3) each have an opening (inlet (51) and outlet (52)). The lower opening in the plane of Figure 3 constitutes the inlet (51), and the upper opening in the plane of Figure 3 constitutes the outlet (52). The inlet (51) and outlet (52) extend along the side edges of the dielectric (32) and penetrate the dielectric (32) in the thickness direction. The inlet (51) communicates with the raw material gas supply unit (21). The outlet (52) communicates with the ozone gas extraction unit (23).

[0026] Cooling passages (45) for cooling the ozone gas generation unit (22) are formed in the other pair of side edges of the dielectric (32) (the left and right side edges in Figure 3). The cooling passages (45) penetrate the dielectric (32) in the thickness direction, and the ozone gas generation unit (22) is cooled by the flow of a coolant through them.

[0027] A partition member (40) is provided inside the dielectric (32). The partition member (40) is made of an insulating material such as a glass-based material. The partition member (40) has a rectangular frame portion (41) along the outer edge of the dielectric (32) and a plurality of ribs (42) that extend linearly across the inlet (51) and outlet (52). The plurality of ribs (42) are arranged parallel to each other along the longitudinal direction of the inlet (51) and outlet (52) so as to be equally spaced from each other.

[0028] The high-pressure side electrode unit (30A) and the low-pressure side electrode unit (30B) are joined together by the top surfaces (42A) of their opposing frame portions (41) and ribs (42) via an adhesive layer (63). This creates a discharge gap (G) between the high-pressure side electrode unit (30A) and the low-pressure side electrode unit (30B). The discharge gap (G) communicates with the inlet (51) and outlet (52). The sides of the discharge gap (G) are sealed except for the inlet (51) and outlet (52) by the ribs (42) or frame portions (41) acting as side walls.

[0029] In such a discharge void (G), oxygen gas flows in the direction of the white arrow in Figure 3. The spacing of the discharge voids (G) is preferably 60 μm or more and 100 μm or less.

[0030] The high-pressure side functional film (33A) is formed on the discharge gap (G) side surface (lower surface in Figure 2) of the high-pressure side dielectric (32A). The low-pressure side functional film (33B) is formed on the discharge gap (G) side surface (upper surface in Figure 2) of the low-pressure side dielectric (32B). Since the configuration of the high-pressure side functional film (33A) and the low-pressure side functional film (33B) is basically the same, they are sometimes collectively referred to as the functional film (33). The functional film (33) is formed in the form of a plate or a film. In addition, the functional film (33) is formed so as to cover the sides of the ribs (42) or frame portions (41) that form the side walls of the discharge gap (G).

[0031] The functional film (33) is formed as a film in which at least the surface on the discharge void (G) side consists only of amorphous components. Glass components may be used as amorphous components. For the purpose of stably generating ozone gas, the functional film (33) may contain boron, zirconium, titanium oxide, etc. For example, it may be a film in which SiO2 is the main component (59-79% by mass), with 10-20% by mass of TiO2, 10-20% by mass of B2O3, and about 1% by mass of ZrO2.

[0032] The discharge void (G) is formed between the lower surface of the high-pressure side functional film (33A) and the upper surface of the low-pressure side functional film (33B). In other words, the high-pressure side functional film (33A) and the low-pressure side functional film (33B) form surfaces that are exposed to the discharge void (G). Oxygen gas flows into the upstream side of the discharge void (G) (for example, the left side in Figure 2). When a high-frequency AC voltage is applied from the power source (25) to the high-pressure side electrode (31A) and the low-pressure side electrode (31B), silent discharge occurs in the discharge void (G). The large number of electrons excited by the discharge generate oxygen radicals such as oxygen atoms, and consequently, ozone gas is produced. The ozone gas produced in the discharge void (G) flows out to the downstream side (for example, the right side in Figure 2).

[0033] If the dielectric (32) is exposed to the discharge void (G) during the generation of ozone gas by such silent discharge, it will cause particles to be generated. In other words, since the dielectric (32) is made of a crystalline material such as alumina, the discharge damages the surface, causing it to peel off into particulate matter and generate particles.

[0034] In contrast to the above, in the ozone gas generation unit (22) of this embodiment, a functional film (33) is formed so as to cover the dielectric (32). The functional film (33) is formed of a film in which at least the surface on the discharge void (G) side consists only of amorphous components, and the crystalline components are not exposed to the discharge void (G). Therefore, particulate peeling does not occur, and the generation of particles can be suppressed.

[0035] The functional film (33) preferably has a thickness of 6 μm or more, from the viewpoint of exhibiting an effect of suppressing particle generation. Furthermore, from the viewpoint of the function of ozone gas generation and the manufacture of the device, the thickness of the functional film (33) is preferably 20 μm or less.

[0036] Furthermore, a configuration in which the electrode unit (30) does not include a dielectric (32) but has an enamel coating applied to a metal electrode plate is also conceivable. In this case, the thickness of the enamel coating must be thicker than the functional film (33) of this disclosure, for example, about 300 to 1000 μm.

[0037] The dielectric strength of a dielectric (32) made of alumina or the like is higher than that of an amorphous film such as glass. Therefore, the configuration of this disclosure, which provides a dielectric (32) on an electrode (31) made of metal and a functional film (33) on its surface, significantly reduces the risk of dielectric breakdown compared to a configuration in which an enamel coating is applied to a metal electrode plate.

[0038] Furthermore, the discharge cell (24) is cooled using the cooling passage (45) to cope with the heat generated during discharge. In this case, it is desirable that the discharge cell (24) has a high thermal conductivity to improve cooling efficiency. Since the thermal conductivity of the dielectric (32) made of alumina or the like is higher than that of the amorphous film formed on the metal electrode plate by enamel processing, the discharge cell (32) of this disclosure has better cooling efficiency than a configuration in which enamel processing is applied to the metal electrode plate. The manufacturing method of the discharge cell (24) of this disclosure will be described later.

[0039] Furthermore, in the configuration of the electrode (31), dielectric (32), and functional film (33) of this disclosure, the thickness of each layer can be reduced, and from this point of view as well, the cooling efficiency is superior to that of a configuration in which an enamel coating is applied to a metal electrode plate.

[0040] Furthermore, in order to improve the efficiency of ozone gas generation, it is desirable to narrow the discharge gap (G). In order to achieve a narrow discharge gap (G), it is necessary to increase the flatness of the surface of the electrode unit (30) that constitutes the discharge gap (G). In this regard, it is easier to control the flatness by printing a functional film on a dielectric sheet by screen printing. Therefore, the configuration of the present disclosure, in which a thin functional film (33) is formed on a dielectric (32), is advantageous in terms of precision control of flatness compared to the conventional configuration in which an amorphous film is formed on a metal electrode plate.

[0041] --Method of manufacturing a discharge cell-- Next, a method for manufacturing the discharge cell (24) of this disclosure will be described. Figure 5 is an example of a method for manufacturing one electrode unit (30) in the discharge cell (24), and shows steps A to E individually. These figures are cross-sectional views showing the area crossing the two ribs (42) in Figure 3.

[0042] In step A, a partition member (40) is formed on one surface of the dielectric (32). The dielectric (32) is cut from a sheet of dielectric material, with the outer shape of the discharge cell (24) and through holes corresponding to the cooling passage (45), inlet (51), and outlet (52). This one surface is the side facing the discharge gap (G) in the discharge cell (24). Figure 5 shows the rib (42) portion of the partition member (40).

[0043] The dielectric (32) may be made of fired alumina. The thickness of the dielectric (32) is preferably 0.9 μm or less. The ribs (42) are formed by screen printing a material film containing a glass-based material onto the surface of the dielectric (32), firing it, and then polishing off the excess. The ribs (42) have a rectangular cross-section with a polished top surface (42A) and side surfaces (42B).

[0044] Next, in step B, a first material film (33C) is formed on the surface of the dielectric (32) where the ribs (42) are formed. The first material film (33C) is formed to cover the surface of the dielectric (32) and the side surface (42B) of the ribs (42), avoiding the top surface (42A) of the ribs (42). This can be achieved by screen printing. In this process, a mask is used in which the area where the first material film (33C) is to be formed has an opening.

[0045] The first material film (33C) is made of a material that, upon firing, will have a film on the discharge void (G) side consisting of amorphous components, such as a material containing glass components. The first material film (33C) may also contain materials other than glass components, such as 10-20% by mass of boronium oxide (B2O3), 10-20% by mass of titanium oxide (TiO2), and 0.5-1.5% by mass of zirconium oxide (ZrO2). Upon firing, the boronium oxide becomes amorphous, similar to the glass components, while the titanium oxide and zirconium oxide become crystalline.

[0046] For proper screen printing, the particle size of the material should preferably be in the range of 7 to 10 μm, for example, with a median diameter (D50). Furthermore, the viscosity of the material paste used for screen printing should preferably be in the range of 100 to 250 Pa·s (25±1℃, 10 rpm).

[0047] Next, in step C, an electrode (31) is formed in a predetermined region on the other surface of the dielectric (32) (the surface opposite to the rib (42) and the first material film (33C) (the surface opposite to the discharge gap (G) in the discharge cell (24)). The electrode (31) may be formed using a metallic material such as Ag+Pd, W, Pt, or Au. The formation method can be CVD (chemical vapor deposition), plating, or the like.

[0048] Next, in step D, a second material film (34A) is formed on the other surface of the dielectric (32), including the area over the electrode (31). In other words, the second material film (34A) is formed so as to cover the portion of the dielectric (32) that is exposed and where the electrode (31) is not formed, and the area over the electrode (31). The second material film (34A) can also be formed, for example, by screen printing.

[0049] The second material film (34A) is a film made of a material that becomes the adhesive layer (34) upon firing, and is, for example, a film made of a material containing a glass component. Here, both the first material film (33C) and the second material film (34A) may be made of materials containing a glass component, but it is preferable that their compositions are different. The second material film (34A) may, for example, have SiO2 as the main component (60-70% by mass), with 1-10% by mass of Al2O3 and 10-20% by mass of B2O3. Using such a composition, the thermal expansion coefficient can be brought closer to that of the dielectric (32) made of alumina by including Al2O3.

[0050] Next, in step E, firing is performed. At this time, the first material film (33C) and the second material film (34A) are fired simultaneously to form a functional film (33) and an adhesive layer (34), respectively. In this case, if the first material film (33C) consists only of glass components, a functional film is formed in which not only the surface on the discharge void (G) side but the entire film consists only of amorphous components. Furthermore, if the first material film (33C) contains not only glass components but also 10-20% by mass of boronium oxide (B2O3), 10-20% by mass of titanium oxide (TiO2), and 0.5-1.5% by mass of zirconium oxide (ZrO2), during firing, the crystalline components of titanium oxide (TiO2) and zirconium oxide (ZrO2) sink to the dielectric (32) side. This is because the specific gravity of titanium oxide (TiO2) and zirconium oxide (ZrO2) is greater than that of the amorphous components (glass material and boronium oxide (B2O3)). Therefore, after firing, the amorphous components with lower specific gravity are present on the surface, and at least on the discharge void (G) side, a functional film (33) consisting only of amorphous components is formed.

[0051] Next, a pair of structures shown in E are prepared, and the same adhesive material as the second material film (34) is screen printed onto the top surface (42A) of each rib (42), and then fired. The top surfaces of the ribs (42) are then heated facing each other with this adhesive material in between, and bonded together. As a result, a discharge cell (24) consisting of a pair of electrode units (30) is formed, as shown in Figures 2 and 4. At the same time, each electrode unit (30) is bonded to other components such as cooling channel members and other discharge cells via the adhesive layer (34), creating a multi-stage structure.

[0052] As described above, the thickness of the functional film (33) is preferably 6 μm or more and 20 μm or less. Such thinness is difficult to achieve by methods such as spray coating. In contrast, in this embodiment, the above thickness can be achieved by forming the first material film (33C) using screen printing.

[0053] In the above explanation, the process of forming a first material film (33C) on one side of the dielectric (32) (step B in Figure 5) is followed by the process of forming a second material film (34A) on the other side (step D in Figure 5). However, this order can be reversed. In other words, the second material film (34A) may be formed first, and then the first material film (33C) may be formed.

[0054] The dielectric (32), made of alumina or the like, and the first material film (33C) or second material film (34A), made of a material containing glass components, have different coefficients of thermal expansion due to the difference in materials. Therefore, as shown in Figure 5, it is desirable to perform firing with the first material film (33C) and the second material film (34A) formed on both sides of the dielectric (32), respectively. In this way, the first material film (33C) and the second material film (34A), although their compositions are different, have similar coefficients of thermal expansion, so when fired simultaneously, both sides of the dielectric (32) expand and contract to the same extent. As a result, warping caused by the difference in the coefficients of thermal expansion of each layer can be suppressed, and firing can be performed while maintaining flatness.

[0055] However, the formation of a functional film (33) consisting solely of amorphous components on the discharge void (G) side surface can be achieved by firing the dielectric (32) with the first material film (33C) formed on one side. In other words, the functional film (33) may be formed by firing after steps A and B in Figure 5, without performing steps C and D.

[0056] Even in this manner, depending on the thickness and material of the dielectric (32) and the first material film (33C), for example, if the first material film (33C) is formed thinly using screen printing as in this embodiment, it may be possible to suppress the occurrence of warping.

[0057] (Variations concerning discharge cells) Figure 6 shows an ozone gas generation unit (22A) of a modified example of the present disclosure and corresponds to Figure 2. Figure 2 shows a discharge cell (24) comprising a high-pressure side electrode unit (30A) and a low-pressure side electrode unit (30B) having similar structures. Each electrode unit (30) in Figure 2 comprises an electrode (31), a dielectric (32), and a functional film (33).

[0058] In contrast, in the discharge cell (24A) of Figure 5, the high-voltage side electrode unit (30A) is the same as that in Figure 2, but the low-voltage side electrode unit (30D) does not have a dielectric and functional film and consists of a low-voltage side electrode (31B). The power supply (25) is connected to the discharge cell (24A) as in Figure 2.

[0059] Thus, the discharge cell (24A) may be configured to include a pair of opposing electrodes (31), a dielectric (32) placed between them, a discharge gap (G) in the dielectric (32), and a functional film (33) covering the surface of the dielectric (32) facing the discharge gap (G).

[0060] In this modified example, the functional film (33) is formed as a film in which at least the surface on the discharge void (G) side consists only of amorphous components. As a result, even in the discharge cell (24A) of this modified example, the generation of particles can be suppressed when generating ozone gas.

[0061] The embodiments described above may be modified in form and detail, provided that they do not deviate from the spirit of the claims. Furthermore, the contents of each embodiment can be combined and substituted as appropriate, as long as they do not impair the functions covered by this disclosure. [Industrial applicability]

[0062] According to this disclosure, it is possible to realize a discharge cell for generating ozone gas that can suppress the generation of particles, and this is useful as an ozone gas generating discharge cell and a method for manufacturing the same. [Explanation of Symbols]

[0063] 20 Ozone gas generator 21 Raw Gas Supply Department 24 discharge cells 24A discharge cell 31 electrode 32 Dielectrics 33 Functional membrane 33C First material film 34 Adhesive layer 34A Second material film 42 Ribs 42A Top surface 42B Side

Claims

1. A discharge cell that generates ozone gas by silent discharge, A pair of opposing electrodes, Displaced between the pair of opposing electrodes is at least one dielectric, A discharge gap formed between the electrode and the dielectric, or between a pair of dielectrics, through which oxygen gas passes, The dielectric comprises a functional film that covers the discharge gap side surface and suppresses the peeling of the discharge cell due to silent discharge, The thickness of the functional film is 6 μm or more. A discharge cell characterized in that at least the surface of the functional film on the discharge void side consists only of amorphous components, and the crystalline components are not exposed to the discharge void.

2. In claim 1, The discharge void comprises an inlet for the oxygen gas and an outlet for the generated ozone gas, and a side wall that seals the sides except for the inlet and the outlet. A discharge cell characterized in that the side wall is covered with the functional film.

3. In claim 1, A discharge cell characterized in that the thickness of the functional film is 20 μm or less.

4. In claim 1, A discharge cell characterized in that the thickness of the dielectric is 0.9 mm or less.

5. The discharge cell according to claim 1, An ozone gas generator characterized by comprising an oxygen supply source that supplies oxygen with a purity of 99.9% or higher to the discharge cell.

6. A method for manufacturing a discharge cell that generates ozone gas by silent discharge, A step of forming a first material film on one side of a dielectric by screen printing, The process includes a step of firing the first material film to form a functional film that suppresses the peeling of the discharge cell due to the silent discharge, A method for manufacturing a discharge cell, characterized in that at least the surface of the functional film on the discharge void side consists only of amorphous components, and the crystalline components are not exposed to the discharge void.

7. In claim 6, A step of forming an electrode on a part of the other surface of the dielectric, The process further comprises the step of forming a second material film having a different composition from the first material film on the other surface of the dielectric, including the electrode, In the process of forming the functional film, the second material film is fired simultaneously with the first material film to form an adhesive layer. A method for manufacturing a discharge cell, characterized in that the functional film and the adhesive layer have different compositions.

8. In claim 6, Prior to the step of forming the first material film, the process further comprises the step of forming ribs having a top surface and side surfaces on one surface of the dielectric, A method for manufacturing a discharge cell, characterized in that the first material film is screen printed on one surface of the dielectric and the side surface of the rib, avoiding the top surface of the rib.

9. In claim 6, A method for manufacturing a discharge cell, characterized by forming the functional film to a thickness of 6 μm or more.

10. In claim 6, A method for manufacturing a discharge cell, characterized by forming the functional film to a thickness of 20 μm or less.

11. In claim 6, A method for manufacturing a discharge cell, characterized in that the thickness of the dielectric is 0.9 mm or less.

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