Film deposition device

Abstract

To provide a film deposition device capable of improving productivity without enlarging the device.SOLUTION: A film deposition device for depositing at least first and second layers on a substrate has a film deposition chamber, a material gas emission system, a gas emission part, and suction means. The material gas emission system has an evaporation part, can supply material gas evaporated by the evaporation part to the gas emission part by carrier gas, and can execute film deposition actions including a first film deposition step for depositing the first layer on the substrate, a carrier gas cleaning step for flowing only the carrier gas having temperature difference within 10°C from the carrier gas used for depositing the first layer to the film deposition chamber from the gas emission part, a suction cleaning step for sucking gas in the film deposition chamber by the suction means, and a second film deposition step for depositing the second layer on the substrate. In the film deposition actions, after the first film deposition step, the carrier gas cleaning step and the suction cleaning step are respectively performed at least once, so as to perform the second film deposition step.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a film forming apparatus for forming a thin film. [Background technology]

[0002] Conventionally, a film forming apparatus for forming a thin film has been used in the manufacture of a solar cell or an organic EL device. For example, Patent Document 1 discloses a vacuum deposition apparatus that can be used for forming each layer of an organic EL device. The deposition apparatus of Patent Document 1 is configured so that powdered thin film forming material is introduced into a vaporization chamber using a high-temperature carrier gas, the thin film forming material is heated in the vaporization chamber, and vaporized or sublimated to generate vapor, the vapor is transported to a deposition chamber using the carrier gas, and a mixture of the carrier gas and vapor is sprayed onto a substrate in the deposition chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-112316 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, when a laminated film consisting of multiple films containing different materials is formed in one film-forming chamber, such as the laminated film consisting of each layer of the organic EL device described above, it is possible that after one film is formed, the material forming the film will remain in the pipe transporting the film material or in the film-forming chamber. In this case, if another film is formed in the same state, the remaining material will be mixed into the other film, and the properties of the product (e.g., organic EL device) may be deteriorated.

[0005] Therefore, after one film is formed, the film formation chamber needs to be cleaned (washed), but if this cleaning takes time and the temperature of the film formation chamber drops, it takes time to start forming the next film, resulting in a problem of reduced productivity. Also, it is conceivable to have a configuration with multiple film formation chambers and form each film constituting the laminated film in a different film formation chamber, but in this case, there is a problem that the device becomes large and complicated.

[0006] Therefore, an object of the present invention is to provide a film forming apparatus that can improve productivity without making the apparatus large-scale. [Means for solving the problem]

[0007] One aspect of the present invention for solving the above-mentioned problems is a film formation apparatus for forming at least a first layer and a second layer on a substrate, the film formation apparatus having a film formation chamber, a material gas discharge system, a gas discharge section, and an suction means, the material gas discharge system having a vaporization section and capable of supplying material gas vaporized in the vaporization section to the gas discharge section by a carrier gas, the film formation apparatus being capable of performing a film formation operation including a first film formation step for forming the first layer on the substrate, a carrier gas cleaning step for flowing only carrier gas having a temperature within 10°C difference from the carrier gas used in forming the first layer from the gas discharge section into the film formation chamber, a suction cleaning step for sucking gas in the film formation chamber by the suction means, and a second film formation step for forming the second layer on the substrate, the film formation operation including performing each of the carrier gas cleaning step and the suction cleaning step at least once after the first film formation step, and then performing the second film formation step.

[0008] According to the film-forming apparatus of this aspect, after the first film-forming process, the carrier gas cleaning process and the suction cleaning process are each performed at least once, and then the second film-forming process is performed. Therefore, when the first layer and the second layer are formed in one film-forming chamber, it is possible to suppress the occurrence of product degradation caused by the material of the first layer being mixed into the second layer. This makes it possible to simplify the apparatus without increasing the number of film-forming chambers more than necessary. In addition, by carrying out a carrier gas cleaning process in which the carrier gas used to supply the material gas is flowed, it is possible to remove the material remaining in the deposition chamber without installing a separate facility for the cleaning process, which also simplifies the device. Furthermore, in the carrier gas cleaning step, a carrier gas with a temperature difference of within 10°C from the carrier gas used in depositing the first layer is flowed, thereby preventing a temperature drop (temperature change) in the deposition chamber caused by carrying out the cleaning step. This makes it possible to carry out the second deposition step as soon as possible after the cleaning step, thereby improving productivity.

[0009] Preferably, in the film forming operation, after the first film forming step, the carrier gas cleaning step and the suction cleaning step are performed alternately.

[0010] According to this aspect, the material remaining in the deposition chamber can be removed more reliably.

[0011] Preferably, in the film forming operation, after the first film forming step, the carrier gas cleaning step and the suction cleaning step are alternately performed three or more times.

[0012] According to this aspect, the material remaining in the deposition chamber can be removed more reliably. Here, in the carrier gas cleaning process of this aspect, as described above, a carrier gas whose temperature is within 10°C of the carrier gas used in depositing the first layer is flowed. Therefore, even if the carrier gas cleaning process and the suction cleaning process are performed alternately multiple times and the cleaning process is performed for a long time, it is possible to prevent a significant temperature change from occurring in the deposition chamber. This makes it possible to more reliably remove the material remaining in the deposition chamber, and also makes it possible to perform the second deposition process as soon as possible. Effect of the Invention

[0013] According to the present invention, it is possible to provide a film forming apparatus capable of improving productivity without making the apparatus large-scale. [Brief description of the drawings]

[0014] [Figure 1] 1 is a configuration diagram illustrating a film forming apparatus according to an embodiment of the present invention. [Diagram 2] 2 is a flowchart showing a film forming operation performed by the film forming apparatus of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described in detail.

[0016] As shown in FIG. 1, the film forming apparatus 1 of the first embodiment of the present invention is a vacuum deposition apparatus equipped with a film forming section 2, a plurality of film forming gas supply sections 3 (3a to 3c), and a plurality of gas supply flow paths 5 (5a to 5c). Specifically, the film forming apparatus 1 is a gas carrier evaporation apparatus that vaporizes or sublimes the thin film forming material in the vaporizer 30 of the film forming gas supply sections 3a to 3c to generate vapor of the thin film forming material (hereinafter also referred to as material vaporization gas), and sprays the film forming gas containing the material vaporization gas onto the substrate 100 in the film forming section 2 to form a thin film that constitutes the organic EL device on the substrate 100.

[0017] The film forming section 2 is equipped with a film forming chamber 20, a substrate holding section 21, a mask section 22, a film forming gas discharge section 23 (gas discharge section), and an exhaust system section 25, and sprays a film forming gas from the film forming gas discharge section 23 onto a substrate 100 arranged in the film forming chamber 20 to form a thin film on the substrate 100.

[0018] The substrate holding section 21 is a section for holding the substrate 100 so that the surface of the substrate 100 on which the film is to be formed faces the film formation gas discharge section 23 . The mask portion 22 is a portion that limits the portion on the substrate 100 where a film is to be formed, and has openings through which the thin film formed on the substrate 100 is patterned.

[0019] The film formation gas discharge part 23 is a part that discharges a film formation gas to the substrate 100, and is specifically a deposition head. That is, the film formation gas discharge part 23 has a gas discharge port, which faces the substrate 100 held by the substrate holding part 21, and blows the film formation gas onto the substrate 100 from the gas discharge port. The film forming gas discharge part 23 of this embodiment has an internal space, and the film forming gases supplied from the film forming gas supply parts 3a to 3c are mixed in the space and can be sprayed from the gas discharge port.

[0020] The exhaust system section 25 is a section that exhausts gas within the film formation chamber 20 to the outside and maintains a substantial vacuum state within the film formation chamber 20. That is, the exhaust system section 25 has a vacuum pump (suction means) such as a rotary pump, and the pressure within the film formation chamber 20 can be reduced by operating the vacuum pump.

[0021] The film forming gas supply unit 3 generates a material-containing gas including a material vaporizing gas, and supplies the film forming gas including the generated material-containing gas to the gas supply passage 5. As shown in FIG. 1, the deposition gas supply unit 3 includes a vaporizer 30, a carrier gas supply unit 31, a material gas connection path 33, and a carrier gas connection path .

[0022] The vaporizer 30 includes a material supply unit 40 , a vaporization-side gas supply unit 41 , a vaporizer 42 , a material supply path 43 , and a gas supply path 44 .

[0023] The material supply unit 40 is a material supply mechanism that quantitatively supplies a solid or liquid thin film forming material to the vaporization unit 42 via a material supply path 43, and also serves as a storage container that temporarily stores the thin film forming material. The thin film forming material used in this embodiment is a powdered solid material that is a powdered solid material at room temperature.

[0024] The material supply unit 40 of the present embodiment is capable of supplying a material dispersion gas in which the thin film forming material is dispersed in a first carrier gas to the material supply path 43. The first carrier gas is an inert gas that does not react with the thin film forming material, and is preferably a rare gas such as nitrogen gas or argon gas, and more preferably argon gas.

[0025] The vaporization-side gas supply unit 41 is a portion that supplies a second carrier gas to the material supply path 43 and adjusts the amount of vaporization of the thin film forming material in the vaporization unit . The second carrier gas is a heated carrier gas that is heated to a temperature equal to or higher than the temperature of the material dispersion gas. The temperature of the second carrier gas supplied from the vaporization-side gas supply unit 41 is appropriately changed depending on the boiling point of the thin film forming material, and is preferably, for example, 100 degrees Celsius or more and 700 degrees Celsius or less. The second carrier gas is an inert gas that does not react with the material dispersion gas, and is preferably a rare gas such as nitrogen gas or argon gas, and more preferably argon gas. The second carrier gas in this embodiment is the same type of gas as the first carrier gas.

[0026] Vaporizing section 42 includes a vaporizing chamber and a heating member, and is a section that heats a mixed gas (hereinafter also referred to as a material mixed gas) of a material dispersion gas (thin film forming material and first carrier gas) and a second carrier gas that is supplied to the inside of the vaporizing chamber. That is, the heating member is disposed so as to surround the vaporizing chamber, which is also a tubular part having an internal space, and the operation of the heating member enables the vaporizing chamber to be heated and kept warm.

[0027] The material supply path 43 is a connection pipe that connects the material supply unit 40 and the vaporization unit 42 (vaporization chamber).

[0028] The gas supply path 44 is a connection pipe that connects the vaporization-side gas supply unit 41 and the middle of the material supply path 43. In other words, the gas supply path 44 is a branch path in which the upstream portion branches off from the material supply path 43.

[0029] The carrier gas supply unit 31 is a unit that supplies a third carrier gas into the gas supply passages 5a to 5c, and adjusts the total flow rate of the film deposition gas released from the film deposition gas release unit 23, thereby adjusting the film deposition speed. The third carrier gas is an inert gas that does not react with the material-containing gas, and is preferably a rare gas such as nitrogen gas or argon gas, and more preferably argon gas. The third carrier gas in this embodiment is the same type of gas as the first carrier gas and the second carrier gas.

[0030] The material gas connection path 33 is a connecting pipe that is continuous with the gas supply flow path 5 and connects the vaporizer 30 (vaporization chamber) to the gas supply flow path 5, and is a part that constitutes the material gas supply flow path that guides the material-containing gas supplied from the vaporizer 30 to the gas supply flow path 5.

[0031] The carrier gas connection path 34 is a connecting pipe that connects the carrier gas supply unit 31 and the middle of the material gas connection path 33, and is a part that constitutes the carrier gas supply flow path that guides the third carrier gas supplied from the carrier gas supply unit 31 to the gas supply flow path 5.

[0032] The gas supply passage 5 connects the film production unit 2 and the film production gas supply unit 3, and is a passage for sending out a film production gas, which is a mixed gas of the material-containing gas and the third carrier gas, from the film production gas supply unit 3 to the film production unit 2.

[0033] In this embodiment, there are a plurality of film deposition gas supply units 3a-3c and a plurality of gas supply passages 5a-5c corresponding to the film deposition gas supply units 3a-3c, respectively. Each pair of one film deposition gas supply unit 3 and a gas supply passage 5 corresponding to one film deposition gas supply unit 3 serves as a material gas discharge system capable of supplying a material vaporization gas (material gas) vaporized by the vaporizer 42 to the film deposition gas discharge unit 23 by a carrier gas.

[0034] More specifically, in the film forming apparatus 1 of this embodiment, when supplying the material mixed gas to the film forming gas discharge section 23, a material dispersion gas in which the thin film forming material is dispersed in a first carrier gas is supplied from the material supply section 40 to the material supply path 43. In addition, a second carrier gas is supplied from the vaporization side gas supply section 41 to the material supply path 43 via the gas supply path 44. As a result, the material dispersion gas supplied from the material supply section 40 is mixed with the second carrier gas at the confluence of the material supply path 43 and the gas supply path 44, and is supplied to the vaporization section 42 (vaporization chamber) as a material mixed gas from the downstream end of the material supply path 43.

[0035] Then, the material mixed gas is heated in the vaporizer 42, whereby the thin film forming material contained in the material mixed gas is vaporized to become a material vaporized gas. Then, a material-containing gas, which is a mixture of the material vaporized gas, the first carrier gas, and the second carrier gas, is introduced into the material gas connection path 33 from the vaporizer chamber. Next, the material-containing gas introduced from the vaporization chamber into the material gas connection path 33 is mixed with the third carrier gas supplied from the carrier gas supply unit 31 midway through the material gas connection path 33 to become a film formation gas, which is introduced into the gas supply flow path 5. Then, the gas is supplied from the gas supply flow path 5 to the film formation gas discharge unit 23, and is discharged from the film formation gas discharge unit 23 onto the substrate 100 fixed to the substrate holding unit 21. Then, the film formation gas discharged onto the substrate 100 is cooled on the substrate 100 and precipitates to form a thin film on the substrate 100. In other words, the film forming gas is a mixture of a material vaporization gas in which only the thin film forming material is vaporized, a first carrier gas, a second carrier gas, and a third carrier gas, and in the film forming apparatus 1 of this embodiment, the material vaporization gas is supplied to the film forming gas release section 23 by the carrier gas.

[0036] As described above, the film forming apparatus 1 of this embodiment has a plurality of film forming gas supply parts 3a to 3c (material gas discharge systems). Therefore, by supplying film forming gases using different thin film forming materials from each of the plurality of film forming gas supply parts 3 to the film forming gas discharge part 23, the plurality of types of film forming gases are mixed in the film forming gas discharge part 23, and a co-deposition film can be co-deposited on the substrate 100.

[0037] That is, the film forming apparatus 1 of this embodiment can supply film forming gases using different thin film forming materials from each of the multiple film forming gas supply parts 3 to the film forming gas discharge part 23. In addition, at that time, it is possible to supply film forming gases from one or multiple film forming gas supply parts 3 to the film forming gas discharge part 23, and spray one type of film forming gas or a gas in which multiple types of film forming gases are mixed onto the substrate 100 to form a thin film. As a result, the film forming apparatus 1 of this embodiment can form multiple types of thin films that constitute each layer of the laminated film of the organic EL device.

[0038] Next, a description will be given of an example of forming a laminated film by the film forming operation performed by the film forming apparatus 1 of this embodiment. The laminated film is formed by stacking n layers (n is an integer of 2 or more) of thin films.

[0039] In the film forming operation of this embodiment, each thin film constituting the laminated film is formed in sequence. Specifically, as shown in FIG. 2, the film forming apparatus 1 performs a film forming step (first film forming step) of forming a thin film that becomes a first layer on a substrate 100 (STEP 1). That is, film deposition gas is supplied from one or more film deposition gas supply parts 3 to the film deposition gas discharge part 23, and one or more types of film deposition gas are sprayed onto the substrate 100 to deposit a thin film that will become the first layer.

[0040] Next, the film forming apparatus 1 executes a carrier gas cleaning step and a suction cleaning step (STEP 2). In detail, a suction cleaning process is performed in which the film deposition chamber 20 is evacuated to a predetermined pressure (vacuum level) and depressurized. In this embodiment, the suction cleaning process is performed with the on-off valve of the gas supply flow path 5 in a closed state and the film deposition gas supply unit 3 and the film deposition chamber 20 disconnected. That is, in this embodiment, the film deposition chamber 20 and a part of the piping used for supplying the film deposition gas (the downstream part of the gas supply flow path 5) are evacuated to a predetermined pressure (first pressure) and depressurized.

[0041] After the suction cleaning process, a carrier gas cleaning process is performed in which a carrier gas is caused to flow from the film formation gas discharge part 23 into the film formation chamber 20. In the carrier gas cleaning process, only a carrier gas that does not contain the thin film formation material or the evaporated thin film formation material (material vaporized gas) and that constitutes a part of the film formation gas is supplied to the film formation chamber 20. At this time, the temperature difference between the carrier gas supplied to the film formation chamber 20 in the carrier gas cleaning process and the carrier gas used in film formation (the carrier gas that becomes part of the film formation gas) is set to within 10° C. In other words, if the temperature of the carrier gas used in the film formation process immediately prior to the implementation of the suction cleaning process is X1° C., the temperature of the carrier gas supplied in the carrier gas cleaning process is set to a temperature within the range of X1-10° C. to X1+10° C.

[0042] The carrier gas supplied to the deposition chamber 20 in the carrier gas cleaning step may be any one of the first carrier gas, the second carrier gas, and the third carrier gas described above, or may be one or more carrier gases selected from these. The carrier gas supplied to the deposition chamber 20 in the carrier gas cleaning step is preferably a carrier gas supplied from the upstream side of the vaporizer 42, from the viewpoint of keeping the temperature difference with the carrier gas used in deposition within 10°C. Furthermore, the carrier gas supplied to the film formation chamber 20 in the carrier gas cleaning step may be a carrier gas supplied from a film formation gas supply unit 3 that supplied a film formation gas in the most recent film formation step, or may be a carrier gas supplied from a film formation gas supply unit 3 that did not supply a film formation gas in the most recent film formation step. Furthermore, the carrier gas supplied to the film formation chamber 20 in the carrier gas cleaning step may be a carrier gas supplied from one film formation gas supply unit 3, or may be a carrier gas supplied from multiple film formation gas supply units 3.

[0043] In the carrier gas cleaning step of this embodiment, the above-mentioned carrier gas is supplied to the film formation chamber 20, and the pressure in the film formation chamber 20 and a part of the piping used to supply the film formation gas (the downstream part of the gas supply flow path 5) is increased to a predetermined pressure (second pressure). At this time, the film formation chamber 20 and a part of the piping may be connected to the exhaust system section 25, or may be disconnected. In addition, the "predetermined pressure" (second pressure) at this time is higher than the "predetermined pressure" (first pressure) in the suction cleaning step. Although not particularly limited, the "predetermined pressure" (second pressure) at this time is preferably higher than the pressure in the film formation chamber 20 in the film formation step.

[0044] The suction cleaning process and the carrier gas cleaning process are each performed a specified number of times. In this embodiment, the number of times (specified number) that the suction cleaning process and the carrier gas cleaning process are both performed is three, and the suction cleaning process and the carrier gas cleaning process are performed alternately. That is, the first suction cleaning process is performed, the first carrier gas cleaning process is performed, the second suction cleaning process is performed, and the second carrier gas cleaning process is performed. Similarly, the third suction cleaning process is performed, and the third carrier gas cleaning process is performed, and so on. That is, the suction cleaning process and the carrier gas cleaning process are alternately performed (STEP 2) until both the suction cleaning process and the carrier gas cleaning process are performed a specified number of times (three times) (while No is returned in STEP 3). Then, when both the suction cleaning process and the carrier gas cleaning process have been performed three times (Yes is returned in STEP 3), a film forming process (second film forming process) is performed to form a thin film that will become the second layer (No is returned in STEP 4, STEP 1).

[0045] In the case of forming a thin film that will be the second layer, the suction cleaning process and the carrier gas cleaning process are performed after the thin film is formed (STEP 2) in the same manner as described above. Then, the suction cleaning process and the carrier gas cleaning process are alternately performed (while No in STEP 3) until both processes are performed a specified number of times (three times) in the same manner as described above. That is, the above-mentioned STEP 1 to STEP 3 are repeated until the thin film that will become the nth layer is deposited and then both the suction cleaning step and the carrier gas cleaning step are performed a specified number of times (while STEP 4 is No). Then, after the thin film that will become the nth layer is deposited, the suction cleaning step and the carrier gas cleaning step are each performed a specified number of times (STEP 4 is Yes), and the deposition operation is completed.

[0046] According to the film formation apparatus 1 of this embodiment, the carrier gas cleaning process is performed by supplying a carrier gas whose temperature difference with the carrier gas used in film formation is within 10°C. Therefore, the film formation chamber 20 can be cleaned without changing the indoor temperature of the film formation chamber 20 significantly from the time of film formation. As a result, the film formation chamber 20 can be used for film formation as soon as possible after cleaning, and production efficiency can be improved. Furthermore, according to the film formation apparatus 1 of the present embodiment, the film formation chamber 20 is cleaned using the carrier gas used to supply the film formation gas, so that the film formation chamber 20 can be cleaned without providing a separate cleaning mechanism, which allows for simplification of the apparatus (downsizing and cost reduction).

[0047] In the above embodiment, the film forming unit 2 has one film forming chamber 20, but the present invention is not limited to this. The film forming unit 2 may have multiple film forming chambers 20. In this case, it is preferable to make the number of film forming chambers 20 smaller than the number of films to be formed on the substrate 100 (the above-mentioned n) from the viewpoint of further simplifying the apparatus.

[0048] In the above embodiment, the number of times (prescribed number of times) the suction cleaning process is performed is the same as the number of times (prescribed number of times) the carrier gas cleaning process is performed, but these may be different. In addition, the suction cleaning process and the carrier gas cleaning process may be performed alternately, or one may be performed consecutively multiple times and then the other may be performed. Furthermore, it is sufficient that the suction cleaning process and the carrier gas cleaning process are performed at least once each, and it is also possible to perform the suction cleaning process and the carrier gas cleaning process only once each after the film forming process. In this case, either the suction cleaning process or the carrier gas cleaning process may be performed first. [Explanation of symbols]

[0049] 1 Film forming equipment 20 Film forming room 23 Film-forming gas release section (gas release section) 42 Vaporizing section 100 Base material

Claims

1. A film forming apparatus for forming at least a first layer and a second layer on a substrate, The apparatus includes a deposition chamber, a material gas discharge system, a gas discharge unit, and a suction means, the material gas emission system has a vaporization unit and is capable of supplying the material gas vaporized in the vaporization unit to the gas emission unit by a carrier gas; a first film forming step of forming the first layer on the base material; a carrier gas cleaning step of flowing only a carrier gas having a temperature within 10° C. of the carrier gas used in the deposition of the first layer from the gas release portion into the deposition chamber; a suction cleaning step of suctioning gas from within the deposition chamber by the suction means; A film forming operation including a second film forming step of forming the second layer on the base material can be performed, In the film forming operation, after the first film forming step, the carrier gas cleaning step and the suction cleaning step are each performed at least once, and then the second film forming step is performed.

2. The film forming apparatus according to claim 1 , wherein in the film forming operation, the carrier gas cleaning step and the suction cleaning step are alternately performed after the first film forming step.

3. The film forming apparatus according to claim 2 , wherein in the film forming operation, after the first film forming step, the carrier gas cleaning step and the suction cleaning step are alternately performed three or more times.

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