Film forming device

Abstract

A purpose of the present disclosure is to provide a film forming device with which the quality and usage efficiency of a raw material solution mist conveyed by a mist supply pipe are improved. In a mist film forming device (51) according to the present disclosure, an ultrasonic atomizer (1) conveys a raw material solution mist (MT) toward a mist supply port (15) of a nozzle (7) via a mist supply pipe (11) by means of a conveying gas (G4). A mist supply direction (D1) of the mist supply pipe (11) includes two partial supply directions (D11 and D12). The angles of elevation of each of the two partial supply directions (D11 and D12) are positive values.

Description

Film forming apparatus

[0001] The present disclosure relates to a film forming apparatus for forming a thin film, and particularly to a film forming apparatus that propagates a raw material solution mist through a mist supply pipe.

[0002] A conventional film forming apparatus for forming a thin film generates a raw material solution mist in which a raw material solution is atomized by an ultrasonic nebulizer, and propagates the raw material solution mist through a mist supply pipe. The film forming apparatus sprays the raw material solution mist from a mist spraying mechanism connected to the mist supply pipe onto a substrate to be film formed, and forms a functional thin film on the surface of the substrate. For example, a nozzle can be considered as the mist spraying mechanism. As a conventional film forming apparatus, for example, a mist coating film forming apparatus disclosed in Patent Document 1 can be cited.

[0003] FIG. 5 is an explanatory diagram schematically showing the configuration of a mist film forming apparatus 91 which is a first conventional apparatus.

[0004] As shown in the figure, the ultrasonic nebulizer 1 applies ultrasonic vibration to the raw material solution in the container to generate a raw material solution mist MT in the container. The ultrasonic nebulizer 1 takes in the carrier gas G4 from the gas supply unit 4 into the container, and conveys the raw material solution mist MT by the carrier gas G4 through the mist supply pipe 31 toward the mist supply port 75 of the nozzle 70.

[0005] The nozzle 70 has a column structure, has a mist supply port 75 on the upper surface, and has a mist ejection port 77 on the lower surface. The nozzle 70 receives the raw material solution mist MT from the mist supply port 75 through the mist supply pipe 31, and supplies the raw material solution mist MT downward from the mist ejection port 77.

[0006] The mist film forming apparatus 91 having such a configuration forms a thin film on the surface of the substrate 21 by applying the raw material solution mist MT to the surface of the substrate 21 to be film formed. The substrate 21 is disposed below the mist ejection port 77. As a method of disposing the substrate 21 below the mist ejection port 77, placing the substrate 21 on a mounting table (not shown) etc. can be considered.

[0007] FIG. 6 is an explanatory diagram schematically showing the configuration of a mist film forming apparatus 92 which is a second conventional apparatus.

[0008] As shown in the figure, the ultrasonic atomizer 1 applies ultrasonic vibrations to the raw material solution in the container to generate a raw material solution mist MT inside the container. The ultrasonic atomizer 1 takes in a transport gas G4 from the gas supply unit 4 into the container, and the transport gas G4 transports the raw material solution mist MT through the mist supply pipe 32 toward the mist supply port 76 of the nozzle 80.

[0009] The nozzle 80 has a columnar structure, with a mist supply port 76 on its lower surface and a mist outlet 78 on its upper surface. The nozzle 80 receives raw material solution mist MT from the mist supply port 76 via the mist supply pipe 32 and supplies the raw material solution mist MT upward from the mist outlet 78.

[0010] In this configuration, the mist film deposition apparatus 92 deposits a thin film on the back surface of the substrate 22 by applying a raw material solution mist MT to the back surface of the substrate 22 to be deposited. The substrate 22 is positioned above the mist outlet 78. One possible method for positioning the substrate 22 above the mist outlet 78 is to hold the substrate 22 with a holding means (not shown).

[0011] International Publication No. 2018 / 011854

[0012] Hereinafter, the mist deposition apparatus 91 shown in Figure 5 and the mist deposition apparatus 92 shown in Figure 6 will be collectively referred to as the "mist deposition apparatus 90," and the mist supply pipe 31 shown in Figure 5 and the mist supply pipe 32 shown in Figure 6 will be collectively referred to as the "mist supply pipe 30."

[0013] In the conventional mist deposition apparatus 90, the mist supply piping 30 had a portion in the mist supply direction where the elevation angle, which is an angle pointing upward with respect to the horizontal direction, was 0° or less.

[0014] In the case of the mist deposition apparatus 91 shown in Figure 5, the mist supply direction D6 of the mist supply pipe 31 includes three partial supply directions D61 to D63. Partial supply direction D61 has an elevation angle of 90°, partial supply direction D62 has an elevation angle of 0°, and partial supply direction D63 has an elevation angle of -90°.

[0015] Therefore, in the mist supply piping 31, there was a problem in that the raw material solution mist MT adhered to the inner wall of the piping corresponding to the partial supply direction D62, causing the raw material solution mist MT to accumulate and form liquid puddles. The liquid puddles refer to the liquid component formed by the aggregate of raw material solution mist MT.

[0016] On the other hand, in the case of the mist deposition apparatus 92 shown in Figure 6, the mist supply direction D7 of the mist supply pipe 32 includes three partial supply directions D71 to D73. Partial supply direction D71 has an elevation angle of +90°, partial supply direction D72 has an elevation angle of -45°, and partial supply direction D73 has an elevation angle of +90°.

[0017] Therefore, the bent portion 32b of the mist supply pipe 32, where it changes from partial supply direction D72 to partial supply direction D73, becomes a valley in the mist supply pipe 32. As a result, there was a problem in that the raw material solution mist MT adhered to the inner wall corresponding to the bent portion 32b, causing the raw material solution mist MT to accumulate and form a liquid pool.

[0018] Thus, the conventional mist deposition apparatus 90 had the problem of liquid accumulation occurring due to the existence of a portion of the mist supply pipe 30 in the mist supply direction where the elevation angle is 0° or less.

[0019] Therefore, when the mist film formation apparatus 90 is used for a long period of time, the liquid generated in the mist supply pipe 30 evaporates, and components of the raw material solution that were dissolved or dispersed in the liquid precipitate. Hereinafter, the precipitated components will be referred to as "precipitated components."

[0020] In particular, if the precipitated components dry and break down during periods when the mist deposition apparatus 90 is not in use, they are transported by the gas flow of the transport gas G4 that flows through the mist supply pipe 30 when the mist deposition apparatus 90 is in use, and are finally blown out together with the raw material solution mist MT from the mist outlet 77 (78) of the nozzle 70 (80).

[0021] Thus, the conventional mist film deposition apparatus 90 had a problem in that the quality of the raw material solution mist MT transported by the mist supply pipe 30 deteriorated because the precipitated components flowed into the mist supply pipe 30.

[0022] When solid precipitate components blown out from the mist outlet 77 are applied to the surface (back surface) of the substrate 21 (22), they become incorporated into the thin film being formed. If precipitate components are incorporated into the thin film, defects and non-uniformity of the film thickness will occur. As a result, the performance of the thin film formed by the mist deposition apparatus 90 will deteriorate.

[0023] Furthermore, if a portion of the mist supply pipe 30 is blocked by liquid accumulation, it leads to a decrease in the efficiency of using the raw material solution mist MT flowing through the mist supply pipe 30. In other words, the conventional mist film formation apparatus 90 has the problem that a portion of the raw material solution mist MT is not supplied to the substrate 21 (22) but remains in the mist supply pipe 30 as liquid accumulation, leading to a decrease in the efficiency of using the raw material solution mist MT.

[0024] This disclosure aims to solve the above-mentioned problems and provide a film deposition apparatus that improves the quality and utilization efficiency of the raw material solution mist transported by the mist supply piping.

[0025] The film deposition apparatus of the present disclosure comprises an ultrasonic atomizer that generates a raw material solution mist by applying ultrasonic vibrations to a raw material solution, and a mist supply pipe for transporting the raw material solution mist generated by the ultrasonic atomizer, wherein the mist supply direction of the mist supply pipe has a positive value greater than 0° in the entire region, where the elevation angle is an angle directed upward with respect to the horizontal direction.

[0026] In the film deposition apparatus of this disclosure, the mist supply direction of the mist supply piping has a positive elevation angle throughout its entire range, thus reliably preventing the accumulation of liquid due to the accumulation of raw material solution mist within the mist supply piping.

[0027] As a result, the film deposition apparatus of this disclosure can improve the quality and utilization efficiency of the raw material solution mist transported by the mist supply piping.

[0028] The purpose, features, aspects, and advantages of this disclosure will become clearer from the following detailed description and accompanying drawings.

[0029] Figure 1 is a schematic diagram illustrating the configuration of a mist deposition apparatus according to Embodiment 1 of the present disclosure. Figure 2 is a schematic diagram illustrating the configuration of a mist deposition apparatus according to Embodiment 2 of the present disclosure. Figure 3 is a schematic diagram illustrating the configuration of a mist deposition apparatus according to Embodiment 3 of the present disclosure. Figure 4 is a schematic diagram illustrating the configuration of a mist deposition apparatus according to Embodiment 4 of the present disclosure. Figure 5 is a schematic diagram illustrating the configuration of a mist deposition apparatus, which is a first conventional apparatus. Figure 6 is a schematic diagram illustrating the configuration of a mist deposition apparatus, which is a second conventional apparatus.

[0030] <Embodiment 1> Figure 1 is a schematic diagram illustrating the configuration of a mist deposition apparatus 51, which is Embodiment 1 of the present disclosure. The deposition apparatus of the present disclosure is the mist deposition apparatus 51.

[0031] As shown in the figure, the ultrasonic atomizer 1 applies ultrasonic vibrations to the raw material solution in the container to generate a raw material solution mist MT inside the container. The ultrasonic atomizer 1 takes in a transport gas G4 from the gas supply unit 4 into the container, and the transport gas G4 transports the raw material solution mist MT through the mist supply pipe 11 towards the mist supply port 15 of the nozzle 7.

[0032] As raw material solutions for mist MT, for example, solutions in which film-forming raw materials are dissolved in a solvent containing water or an organic solvent can be considered. As organic solvents, alcohol-based solvents such as ethanol and methanol, and hydrocarbon-based solvents such as toluene and benzene can be considered.

[0033] Furthermore, zinc acetate, aluminum acetate, nickel acetate, zinc acetylacetonate, aluminum acetylacetonate, nickel acetylacetonate, tin chloride, aluminum chloride, and zinc chloride can be considered as film-forming raw materials.

[0034] Furthermore, a dispersion of fine particles in water or an organic solvent can be considered as a raw material solution. Possible fine particles to be used as film-forming raw materials include carbon nanotubes, silica, barium titanate fine particles, and tin oxide fine particles.

[0035] The nozzle 7 has a columnar structure, with a mist supply port 15 on its side and a mist outlet 17 on its bottom. The final end of the mist supply piping 11 (the right end in the figure) is connected to the mist supply port 15. The nozzle 7 receives the raw material solution mist MT from the mist supply port 15 via the mist supply piping 11 and supplies the raw material solution mist MT downwards from the mist outlet 17.

[0036] A conventional mist film deposition apparatus 91 with this configuration deposits a thin film on the surface of a substrate 21 by applying a raw material solution mist MT to the surface of the substrate 21 to be deposited. The substrate 21 is positioned below the mist outlet 17. One possible way to position the substrate 21 below the mist outlet 17 is to place the substrate 21 on a mounting platform (not shown).

[0037] As shown in Figure 1, in the mist deposition apparatus 51 of Embodiment 1, the mist supply direction D1 of the mist supply pipe 11 includes two partial supply directions D11 and D12. The elevation angle of partial supply direction D11 is 90°, and the elevation angle of partial supply direction D12 is approximately 15°.

[0038] The partial supply directions D11 and D12 are continuous in the order of D11 and D12, and the elevation angles of the partial supply directions D11 and D12 are positive values.

[0039] Furthermore, the mist supply pipe 11 has an inner wall that is treated with a water-repellent coating. Possible examples of a water-repellent inner wall include an inner wall coated with a water-repellent material that has a contact angle with water of 90° or more, or an inner wall of the mist supply pipe 11 made of the aforementioned water-repellent material. The contact angle refers to the angle between a liquid droplet and the solid to which the droplet adheres. Examples of the aforementioned water-repellent materials include fluororesins and silicone resins.

[0040] Thus, in the mist supply piping 11, the mist supply direction D1, including the partial supply directions D11 and D12, has a positive elevation angle greater than 0° in the entire region, which is an angle that points upward with respect to the horizontal direction.

[0041] Therefore, even if the raw material solution mist MT adheres to the inner wall of the mist supply pipe 11, the liquid component of the adhered raw material solution mist MT moves in the opposite direction inside the mist supply pipe 11 due to gravity, and finally flows back into the container of the ultrasonic nebulizer 1.

[0042] Therefore, in the mist film forming apparatus 51 of the first embodiment, due to the adhesion of the raw material solution mist MT to the inner wall of the mist supply pipe 11, the raw material solution mist MT does not accumulate and form a liquid pool.

[0043] As described above, in the mist supply direction D1 of the mist supply pipe 11 in the mist film forming apparatus 51 of the first embodiment, the elevation angle has a positive value in the entire region including the partial supply direction D11 and the partial supply direction D12. Therefore, it is possible to reliably avoid the occurrence of a liquid pool due to the accumulation of the raw material solution mist MT in the mist supply pipe 11.

[0044] As a result, the mist film forming apparatus 51 of the first embodiment can improve the quality and usage efficiency of the raw material solution mist MT conveyed by the mist supply pipe 11 and supplied to the outside from the mist outlet 17 of the nozzle 7.

[0045] This is because, unlike the conventional mist film forming apparatus 90 described with reference to FIGS. 5 and 6, the deposition component does not flow in the mist supply pipe 11, and a part of the mist supply pipe 11 is not blocked by a liquid pool.

[0046] Furthermore, by using the nozzle 7 in the mist film forming apparatus 51 of the first embodiment, the supply range of the raw material solution mist MT from the mist outlet 17 of the nozzle 7 can be expanded.

[0047] In addition, in the mist film forming apparatus 51 of the first embodiment, since the mist supply pipe 11 has two partial supply directions D11 and D12, the degree of freedom in the arrangement of the ultrasonic nebulizer 1 and the nozzle 7 can be increased.

[0048] Furthermore, since the mist supply pipe 11 has an inner wall subjected to a water repellent treatment, the liquid return efficiency of the raw material solution mist MT adhering to the inner wall flowing in the opposite direction in the mist supply pipe 11 and finally flowing back into the container of the ultrasonic nebulizer 1 can be enhanced.

[0049] <Embodiment 2>FIG. 2 is an explanatory diagram schematically showing the configuration of a mist film forming apparatus 52 according to Embodiment 2 of the present disclosure. The film forming apparatus of the present disclosure is the mist film forming apparatus 52.

[0050] Hereinafter, the same contents as those of the mist film forming apparatus 51 shown in FIG. 1 will be described with the same reference numerals and the description will be appropriately omitted as needed. The description will focus on the characteristic parts of the mist film forming apparatus 52 of Embodiment 2.

[0051] The ultrasonic nebulizer 1 takes in the carrier gas G4 from the gas supply unit 4 into the container, and conveys the raw material solution mist MT toward the mist supply port 15 of the nozzle 8 through the mist supply pipe 12 by the carrier gas G4.

[0052] The nozzle 8 has a column structure, has a mist supply port 15 on the side surface, and has a mist outlet 18 on the upper surface. The terminal end (the right end in the figure) of the mist supply pipe 12 is connected to the mist supply port 15. The nozzle ⑧ receives the raw material solution mist MT from the mist supply port 15 through the mist supply pipe 12, and supplies the raw material solution mist MT upward from the mist outlet 18.

[0053] In order to supply the raw material solution mist MT upward, it is desirable to increase the flow rate of the carrier gas G4 in the ultrasonic nebulizer 1 as compared with the mist film forming apparatus 51 of Embodiment 1 for the mist film forming apparatus 52 of Embodiment 2.

[0054] The nozzle 8 has a discharge pipe 81 on the side surface on the lower surface side. The discharge pipe 81 is provided to discharge the residue inside the nozzle 8. As the residue of the nozzle 8, a liquid pool formed by the accumulation of the raw material solution mist MT due to the adhesion of the raw material solution mist MT on the lower surface of the nozzle 8 is conceivable. It is desirable that the discharge pipe 81 provided on the side surface of the nozzle 8 is closer to the lower surface of the nozzle 8.

[0055] In the second embodiment of this configuration, the mist film deposition apparatus 52 deposits a thin film on the back surface of the substrate 22 by applying a raw material solution mist MT to the back surface of the substrate 22 to be deposited. The substrate 22 is positioned above the mist outlet 18. As a method of positioning the substrate 22 above the mist outlet 78, it is conceivable to hold the substrate 22 with a holding means (not shown) that has a suspension function.

[0056] As shown in Figure 2, in the mist deposition apparatus 52 of the second embodiment, the mist supply direction D2 of the mist supply pipe 12 includes two partial supply directions D21 and D22. Partial supply direction D21 has an elevation angle of 90°, and partial supply direction D22 has an elevation angle of approximately 15°. Partial supply directions D21 and D22 are continuous in the order of D21 and D22, and the elevation angles of each of the partial supply directions D21 and D22 are positive values.

[0057] Furthermore, the mist supply pipe 12 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1.

[0058] Thus, in the mist supply piping 12, the mist supply direction D2, including the partial supply directions D21 and D22, has a positive value where the water elevation angle exceeds 0° throughout the entire region.

[0059] Therefore, even if the raw material solution mist MT adheres to the inner wall of the mist supply pipe 12, the liquid component of the adhered raw material solution mist MT moves in the reverse direction inside the mist supply pipe 12 due to gravity and eventually flows back into the container of the ultrasonic atomizer 1.

[0060] Therefore, in the second embodiment, the mist film forming apparatus 52 does not cause the raw material solution mist MT to accumulate and form a pool of liquid due to the adhering of the raw material solution mist MT to the inner wall of the mist supply pipe 12.

[0061] As described above, in the mist deposition apparatus 52 of Embodiment 2, the mist supply direction D2 of the mist supply pipe 12 has a positive elevation angle in the entire region, including the partial supply direction D21 and the partial supply direction D22. Therefore, it is possible to reliably avoid the occurrence of liquid accumulation due to the accumulation of raw material solution mist MT in the mist supply pipe 12.

[0062] As a result, the mist film forming apparatus 52 of the second embodiment can improve the quality and efficiency of the raw material solution mist MT, which is transported by the mist supply pipe 12 and supplied to the outside from the mist outlet 18 of the nozzle 8.

[0063] Furthermore, since the nozzle 8 in the mist film forming apparatus 52 of Embodiment 2 has a mist outlet 18 on its upper surface, it is possible to effectively suppress the occurrence of liquid accumulation caused by the accumulation of raw material solution mist MT around the mist outlet 18 and its surroundings within the nozzle 8.

[0064] This is because even if the raw material solution mist MT temporarily adheres to the mist outlet 18 and its surroundings within the nozzle 8, it quickly falls off due to gravity.

[0065] In addition, since the nozzle 8 has a discharge pipe 81, even if the raw material solution mist MT adheres to the lower surface of the nozzle 8 and accumulates, the accumulated liquid can be discharged from the discharge pipe 81.

[0066] Therefore, the mist film forming apparatus 52 of the second embodiment can suppress the deterioration of the quality of the raw material solution mist MT supplied to the outside from the nozzle 8.

[0067] In addition, the mist film formation apparatus 52 of the second embodiment has two partial supply directions D21 and D22 of the mist supply pipe 12, which increases the degree of freedom in the arrangement of the ultrasonic atomizer 1 and the nozzle 8.

[0068] Furthermore, since the mist supply pipe 12 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1, the raw material solution mist MT adhering to the inner wall flows in the reverse direction through the mist supply pipe 12, and ultimately flows back into the container of the ultrasonic atomizer 1, thereby improving the liquid return efficiency.

[0069] <Embodiment 3> Figure 3 is a schematic diagram illustrating the configuration of a mist deposition apparatus 53, which is Embodiment 3 of the present disclosure. The mist deposition apparatus 53 is the deposition apparatus of the present disclosure.

[0070] In the following description, similar components to those shown in Figure 1 (mist deposition apparatus 51) and Figure 2 (mist deposition apparatus 52) will be given the same reference numerals, and explanations will be omitted as appropriate. The focus will be on the distinctive features of the mist deposition apparatus 53 of Embodiment 3.

[0071] The ultrasonic atomizer 1 takes in transport gas G4 from the gas supply unit 4 into the container, and uses the transport gas G4 to transport the raw material solution mist MT through the mist supply pipe 13 towards the mist supply port 16 of the nozzle 9.

[0072] The nozzle 9 has a columnar structure, with a mist supply port 16 on its lower surface and a mist outlet 18 on its upper surface. The final end (upper end in the figure) of the mist supply piping 13 is connected to the mist supply port 16. The nozzle 9 receives the raw material solution mist MT from the mist supply port 16 via the mist supply piping 13 and supplies the raw material solution mist MT upward from the mist outlet 18.

[0073] The nozzle 9 has a discharge pipe 81 on its lower side. The discharge pipe 81 is provided to discharge any remaining material inside the nozzle 9. The remaining material inside the nozzle 9 is thought to be a liquid accumulation formed by the accumulation of raw material solution mist MT. It is preferable that the discharge pipe 81 provided on the side of the nozzle 9 be close to the lower surface of the nozzle 9.

[0074] In this embodiment 3, the mist film deposition apparatus 53 deposits a thin film on the back surface of the substrate 22 by applying a raw material solution mist MT to the back surface of the substrate 22 to be deposited. The substrate 22 is positioned above the mist outlet 18.

[0075] As shown in Figure 3, in the mist deposition apparatus 53 of Embodiment 3, the mist supply direction D3 of the mist supply pipe 13 is single and the elevation angle is constant at 90°. Furthermore, the mist supply pipe 13 has a pipe diameter (inner diameter) of 35.7 mm. It is desirable that the pipe diameter (inner diameter) of the mist supply pipe 14 be 23 mm or more.

[0076] Furthermore, the mist supply pipe 13 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1.

[0077] Thus, in the mist supply piping 13, the mist supply direction D3 has a positive value where the water elevation angle exceeds 0° throughout the entire region.

[0078] Therefore, even if the raw material solution mist MT adheres to the inner wall of the mist supply pipe 13, the liquid component of the adhered raw material solution mist MT moves in the reverse direction inside the mist supply pipe 13 due to gravity and eventually flows back into the container of the ultrasonic atomizer 1.

[0079] Therefore, in the third embodiment, the mist film forming apparatus 53 does not accumulate liquid due to the raw material solution mist MT adhering to the inner wall of the mist supply pipe 13.

[0080] As described above, in the mist deposition apparatus 53 of Embodiment 3, the mist supply direction D3 of the mist supply pipe 13 has a positive elevation angle throughout its entire range. Therefore, it is possible to reliably avoid the occurrence of liquid accumulation due to the accumulation of raw material solution mist MT inside the mist supply pipe 13.

[0081] As a result, the mist film forming apparatus 53 of Embodiment 3 can improve the quality and efficiency of the raw material solution mist MT, which is transported by the mist supply pipe 13 and supplied to the outside from the mist outlet 18 of the nozzle 9.

[0082] Furthermore, since the nozzle 9 in the mist film forming apparatus 53 of Embodiment 3 has a mist outlet 18 on its upper surface, it is possible to effectively suppress the occurrence of liquid accumulation caused by the accumulation of raw material solution mist MT around the mist outlet 18 and its surroundings within the nozzle 9.

[0083] In addition, since the nozzle 9 has a discharge pipe 81, even if a liquid accumulation occurs due to the accumulation of raw material solution mist MT on the lower surface of the nozzle 9, the liquid accumulation can be discharged from the discharge pipe 81.

[0084] Therefore, the mist film formation apparatus 53 of Embodiment 3 can suppress the deterioration of the quality of the raw material solution mist MT supplied to the outside from the nozzle 9.

[0085] In the mist deposition apparatus 53 of Embodiment 3, the mist supply pipe 13 has a constant elevation angle of 90° in the mist supply direction D3, which is the steepest angle. This makes it possible to most reliably avoid the occurrence of the liquid accumulation described above.

[0086] In addition, by setting the diameter of the mist supply pipe 13 to a sufficiently wide 35.7 mm, there will be no obstruction to the flow of the raw material solution mist MT from the mist supply pipe 13 toward the nozzle 9.

[0087] This is because, by making the diameter of the mist supply pipe 13 sufficiently wide, even if there is raw material solution mist MT that naturally falls from the mist supply port 16 of the nozzle 9 into the mist supply pipe 13, the original flow of raw material solution mist MT from the mist supply pipe 13 toward the nozzle 9 will not be obstructed.

[0088] Furthermore, in order to ensure the proper flow of the raw material solution mist MT from the mist supply pipe 13 towards the nozzle 9, it is desirable that the pipe diameter (inner diameter) of the mist supply pipe 13 be 23 mm or larger.

[0089] Furthermore, since the mist supply pipe 13 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1, the raw material solution mist MT adhering to the inner wall flows in the reverse direction through the mist supply pipe 13, and ultimately flows back into the container of the ultrasonic atomizer 1, thereby improving the liquid return efficiency.

[0090] <Embodiment 4> Figure 4 is a schematic diagram illustrating the configuration of a mist deposition apparatus 54, which is Embodiment 4 of the present disclosure. The deposition apparatus of the present disclosure is the mist deposition apparatus 54.

[0091] In the following description, similar components to the mist deposition apparatus 51 shown in Figure 1, the mist deposition apparatus 52 shown in Figure 2, and the mist deposition apparatus 53 shown in Figure 3 will be given the same reference numerals, and their descriptions will be omitted as appropriate. The description will focus on the distinctive features of the mist deposition apparatus 54 of Embodiment 4.

[0092] The ultrasonic atomizer 1 takes in transport gas G4 from the gas supply unit 4 into the container, and uses the transport gas G4 to transport the raw material solution mist MT through the mist supply pipe 14 towards the mist supply port 16 of the nozzle 9.

[0093] The nozzle 9 has a columnar structure, with a mist supply port 16 on its lower surface and a mist outlet 18 on its upper surface. The final end (upper end in the figure) of the mist supply piping 14 is connected to the mist supply port 16. The nozzle 9 receives the raw material solution mist MT from the mist supply port 16 via the mist supply piping 14 and supplies the raw material solution mist MT upward from the mist outlet 18.

[0094] The nozzle 9 has a discharge pipe 81 on its lower side. The discharge pipe 81 is provided to discharge any remaining material inside the nozzle 9. It is preferable that the discharge pipe 81, which is provided on the side of the nozzle 9, be located close to the lower surface of the nozzle 9.

[0095] In this embodiment 4, the mist film deposition apparatus 54 deposits a thin film on the back surface of the substrate 22 by applying a raw material solution mist MT to the back surface of the substrate 22 to be deposited. The substrate 22 is positioned above the mist outlet 18.

[0096] As shown in Figure 4, in the mist deposition apparatus 54 of Embodiment 4, the mist supply direction D4 of the mist supply pipe 14 includes three partial supply directions D41 to D43. Partial supply direction D41 has an elevation angle of 90°, partial supply direction D42 has an elevation angle of approximately 25°, and partial supply direction D43 has an elevation angle of 90°.

[0097] The partial supply directions D41 to D43 are continuous in the order of D41, D42, and D43, and the elevation angles of each of the partial supply directions D41 to D43 are positive values.

[0098] Furthermore, the mist supply pipe 14 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1.

[0099] Thus, in the mist supply piping 14, the mist supply direction D4, including the partial supply directions D41 to D43, has a positive value where the water elevation angle exceeds 0° throughout the entire region.

[0100] Therefore, even if the raw material solution mist MT adheres to the inner wall of the mist supply pipe 14, the liquid component of the adhered raw material solution mist MT moves in the reverse direction inside the mist supply pipe 14 due to gravity and eventually flows back into the container of the ultrasonic atomizer 1.

[0101] Therefore, in the mist film forming apparatus 54 of Embodiment 4, the raw material solution mist MT does not accumulate and form a pool of liquid due to the adhering of the raw material solution mist MT to the inner wall of the mist supply pipe 14.

[0102] As described above, in the mist film deposition apparatus 54 of Embodiment 4, the mist supply direction D4 of the mist supply pipe 14 has a positive elevation angle in the entire region, including the partial supply direction D41 and the partial supply direction D42. Therefore, it is possible to reliably avoid the occurrence of liquid accumulation due to the accumulation of raw material solution mist MT in the mist supply pipe 14.

[0103] As a result, the mist film forming apparatus 54 of Embodiment 4 can improve the quality and efficiency of the raw material solution mist MT, which is transported by the mist supply pipe 14 and supplied to the outside from the mist outlet 18 of the nozzle 9.

[0104] Furthermore, since the nozzle 9 in the mist film forming apparatus 54 of Embodiment 4 has a mist outlet 18 on its upper surface, it is possible to effectively suppress the occurrence of liquid accumulation caused by the accumulation of raw material solution mist MT around the mist outlet 18 and its surroundings within the nozzle 9.

[0105] In addition, since the nozzle 9 has a discharge pipe 81, it is possible to suppress the deterioration of the quality of the raw material solution mist MT supplied to the outside from the nozzle 9, similar to the mist film formation apparatus 52 of Embodiment 2.

[0106] Furthermore, in the mist film formation apparatus 54 of the fourth embodiment, since the mist supply pipe 14 has three partial supply directions D41 to D43, the degree of freedom in arranging the ultrasonic atomizer 1 and the nozzle 9 can be increased.

[0107] In addition, since the mist supply pipe 14 has an inner wall that is treated with a water-repellent coating, similar to the mist supply pipe 11 in Embodiment 1, the raw material solution mist MT adhering to the inner wall flows in the reverse direction through the mist supply pipe 14, and the liquid return efficiency can be increased as it eventually flows back into the container of the ultrasonic atomizer 1.

[0108] <Other> Although this disclosure has been described in detail, the above description is illustrative in all respects and the disclosure is not limited thereto. It is understood that countless variations not illustrated may be conceivable without falling outside the scope of this disclosure.

[0109] For example, in the embodiment described above, the number of bends where the partial supply direction changes was "0" to "2", but it is also possible to set "3" or more bends. In the embodiment described above, the supply direction of the mist supply pipes 11 to 14 all had a linear component, but under conditions where the elevation angle is a positive value, a curved line segment may be included in at least a part of the mist supply pipe.

[0110] 1 Ultrasonic atomizer 4 Gas supply unit 7-9 Nozzles 11-14 Mist supply piping 15, 16 Mist supply port 17, 18 Mist outlet 21, 22 Substrate 81 Discharge pipe D1-D4 Mist supply direction

Claims

1. A film deposition apparatus comprising an ultrasonic atomizer for generating a raw material solution mist by applying ultrasonic vibrations to a raw material solution, and a mist supply pipe for transporting the raw material solution mist generated by the ultrasonic atomizer, wherein the mist supply direction of the mist supply pipe has a positive elevation angle greater than 0° in the entire region, with respect to the horizontal direction.

2. A film-forming apparatus according to claim 1, further comprising a nozzle that receives the raw material solution mist from a mist supply port via the mist supply piping and supplies the raw material solution mist to the outside from a mist outlet.

3. A film-forming apparatus according to claim 2, wherein the nozzle has a columnar structure, the nozzle has a mist outlet on its upper surface, and supplies the raw material solution mist upward from the mist outlet.

4. A film-forming apparatus according to claim 3, wherein the nozzle further comprises a discharge pipe for discharging internal residue.

5. A film deposition apparatus according to any one of claims 2 to 4, wherein the mist supply direction includes a plurality of partial supply directions, each having a different elevation angle, and each of the plurality of mist supply directions has a positive elevation angle.

6. A film deposition apparatus according to claim 3 or claim 4, wherein the mist supply direction is a single mist supply direction, the elevation angle of the mist supply direction is 90°, and the nozzle has the mist supply port on its lower surface.

7. A film deposition apparatus according to claim 6, wherein the diameter of the mist supply pipe is set to 23 mm or more.

8. A film-forming apparatus according to any one of claims 1 to 7, wherein the mist supply pipe has an inner wall that has been treated with a water-repellent coating.

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