Film forming apparatus and manufacturing method thereof

Abstract

A film forming apparatus according to one embodiment of the present invention is provided with a vacuum chamber, a conveyance roller, a vapor deposition source, a monitoring unit, and a control unit. The conveyance roller is disposed inside the vacuum chamber and supports a film-like substrate. The vapor deposition source is provided with: a vapor deposition boat having a housing part for housing an evaporation material that is vapor-deposited on the substrate supported by the transport roller; and a material supply unit that supplies the evaporation material to the accommodation unit, and the evaporation source melts the evaporation material accommodated in the accommodation unit by electrically heating the evaporation boat. The monitoring unit includes a camera unit that acquires an image of the melt of the evaporation material in the housing unit. The control unit controls, on the basis of the output of the monitoring unit, at least one of the supply speed or supply position of the evaporation material in the vapor deposition source to the storage unit, and the energization power to the vapor deposition boat.

Description

Technical Field

[0001] This invention relates to a wound film-forming apparatus and its manufacturing method. Background Technology

[0002] Conventionally, film-forming apparatuses are known that continuously unwind a long strip of raw material film from an unwinding roller, wind it onto a cooling roller, deposit a vapor-depositing substance from an evaporation source disposed opposite to the cooling roller onto the raw material film, and retract the deposited raw material film with a take-up roller (see, for example, Patent Document 1).

[0003] Furthermore, as a vapor deposition source for such a film-forming apparatus, there is known, for example, a so-called resistance heating type vapor deposition source, which has: a vapor deposition boat having a housing portion for vapor deposition material; and a material supply unit that supplies linear vapor deposition material to the vapor deposition boat and heats the vapor deposition boat to cause the vapor deposition material to evaporate within the housing portion (see, for example, Patent Document 2).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 3795518;

[0007] Patent Document 2: Japanese Patent No. 7404582. Summary of the Invention

[0008] The problem the invention aims to solve

[0009] In roll-to-roll film deposition apparatuses with resistance-heated vapor deposition sources, it is necessary to maintain a stable vapor deposition rate and suppress the reduction in product yield caused by splashing (boiling over). However, the current situation is that the frequency of splashing varies significantly with the melting rate and melt volume of the vapor deposition material in the vapor deposition source, and no effective technology for suppressing splashing has yet been established.

[0010] In view of the above, the object of the present invention is to provide a film forming apparatus and a control method thereof that can maintain a stable evaporation rate and suppress the reduction in product yield caused by splashing.

[0011] Solution for solving the problem

[0012] One aspect of the film-forming apparatus of the present invention includes: a vacuum chamber, a transport roller, a vapor deposition source, a monitoring unit, and a control unit.

[0013] The conveying roller is disposed inside the vacuum chamber to support the film-like substrate.

[0014] The vapor deposition source includes: a vapor deposition boat having a receiving portion for evaporating material, the evaporating material being vapor deposited onto the substrate supported on the conveying roller; and a material supply portion supplying the evaporating material to the receiving portion, the vapor deposition source melting the evaporating material contained in the receiving portion by electrically heating the vapor deposition boat.

[0015] The monitoring unit includes a camera unit that acquires images of the molten evaporating material within the containment unit.

[0016] Based on the output of the monitoring unit, the control unit controls at least one of the following: the supply speed or supply position of the evaporation material from the evaporation source to the receiving unit, and the power supplied to the evaporation boat.

[0017] The control unit may also be configured to acquire information related to the area of ​​the melt based on the output of the monitoring unit, and control the vapor deposition source in such a way that the ratio of the area of ​​the melt to the area of ​​the receiving unit is more than a predetermined value.

[0018] The control unit may also be configured to acquire information related to the depth of the melt based on the output of the monitoring unit, and control the vapor deposition source in a manner specified below the depth of the melt.

[0019] The control unit may also be configured to acquire information related to the melting amount of the evaporation material based on the output of the monitoring unit, and control the evaporation source in such a way that the melting amount of the evaporation material is within a specified range.

[0020] The evaporation material can also be a linear evaporation material.

[0021] The camera unit may also include infrared cameras and visible light cameras.

[0022] In a control method for a film-forming apparatus according to one aspect of the present invention, the film-forming apparatus comprises:

[0023] Vacuum chamber;

[0024] A conveying roller, disposed inside the vacuum chamber, supports the film-like substrate; and

[0025] A vapor deposition source includes: a vapor deposition boat made of a heat-generating material and having a receiving portion for evaporating material, the evaporating material being vapor-deposited onto a substrate supported on a conveying roller; and a material supply unit supplying the evaporating material to the receiving portion, the vapor deposition source melting the evaporating material contained in the receiving portion by electrically heating the vapor deposition boat.

[0026] In the control method of film-forming device

[0027] Acquire camera images of the molten evaporating material within the containment chamber.

[0028] Based on the camera image, control at least one of the following: the supply speed or supply position of the evaporation material in the evaporation source to the receiving part, and the power of the evaporation boat.

[0029] Invention Effects

[0030] According to the present invention, a stable vapor deposition rate can be maintained, and the reduction in product yield caused by splashing can be suppressed. Attached Figure Description

[0031] Figure 1 This is a schematic structural diagram of a film-forming apparatus according to one embodiment of the present invention.

[0032] Figure 2 This is a schematic perspective view showing the structure of the vapor deposition source of the above-mentioned film-forming apparatus.

[0033] Figure 3 This is a schematic side sectional view of the aforementioned vapor deposition source.

[0034] Figure 4 This is a schematic side sectional view showing an example of the morphology of the molten liquid inside the vapor deposition boat.

[0035] Figure 5 Is Figure 4 The diagram illustrates the principle of splashing in the vapor deposition source.

[0036] Figure 6 This is a schematic side sectional view showing another example of the morphology of the molten liquid inside the vapor deposition boat.

[0037] Figure 7 Is Figure 6 The diagram illustrates the principle of splashing in the vapor deposition source.

[0038] Figure 8 This is a simulation result of the heat distribution of the vapor deposition boat.

[0039] Figure 9 This is an experimental result representing the relationship between the surface area ratio of the molten material being evaporated and the amount of splashing.

[0040] Figure 10 This is an experimental result showing the relationship between the surface area variation rate of the above-mentioned melt and the number of splashes and the amount of evaporating material melted.

[0041] Figure 11 This is a schematic side sectional view of the vapor deposition boat, used to illustrate the supply location of the evaporation material and the supply of the evaporation material to the vapor deposition boat.

[0042] Figure 12 This is a flowchart illustrating an example of the processing steps performed in the control unit of the aforementioned film-forming apparatus.

[0043] Figure 13 This is a schematic side sectional view of a vapor deposition boat, used to illustrate the method for calculating the depth of the molten liquid inside the boat. Detailed Implementation

[0044] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0045] Figure 1 This is a schematic structural diagram of a film-forming apparatus 100 according to one embodiment of the present invention. The film-forming apparatus 100 of this embodiment is configured as a roll-to-roll vacuum evaporation apparatus.

[0046] [Basic structure of film-forming device]

[0047] The film forming apparatus 100 of this embodiment includes: a vacuum chamber 10, a vapor deposition source 20, a film transport unit 30, a monitoring unit 40, and a control unit 50.

[0048] (Vacuum chamber)

[0049] Vacuum chamber 10 is a sealed metal container connected to ground. Vacuum chamber 10 is connected to an exhaust line 13, which includes a vacuum pump 11 and a vacuum valve 12. The internal configuration of vacuum chamber 10 allows exhaust to be vented to a specified depressurized environment or maintained at a specified depressurized environment via the exhaust line 13.

[0050] Vacuum chamber 10 houses vapor deposition source 20 and film transport unit 30. A partition 14 is provided inside vacuum chamber 10, which divides the interior of vacuum chamber 10 into film formation chamber 15 and transport chamber 16.

[0051] (Evaporation source)

[0052] The vapor deposition source 20 is a film-forming unit that heats and evaporates the evaporation material. Figure 2 This is a schematic three-dimensional view showing the structure of the vapor deposition source 20. Figure 3 This is a schematic side sectional view. The vapor deposition source 20 has a vapor deposition boat 21 and a material supply unit 22.

[0053] The vapor deposition boat 21 is made of a plate of a high-melting-point material that can be heated to a temperature higher than the melting point of the evaporation material M by applying electricity. The high-melting-point material can be, for example, a ceramic material such as boron nitride, or a metallic material such as molybdenum, tungsten, or tantalum. Regarding the vapor deposition boat 21, for example, multiple boats are arranged with their long sides facing the transport direction of the film F, and multiple boats are arranged in the width direction of the film F.

[0054] The vapor deposition boat 21 has a receiving portion 21a on its upper surface facing the main roller 33, which contains the evaporation material M and its molten liquid Mm. The receiving portion 21a is a rectangular recess of depth D formed on the upper surface of the vapor deposition boat 21. Terminal portions 21b connected to a power supply circuit 23 are provided at both ends of the long side of the vapor deposition boat 21. The evaporation material contained in the receiving portion 21a is melted by heating with current supplied from the power supply circuit 23. The power supply circuit 23 is located outside the vacuum chamber 10, and the power supplied to the vapor deposition boat 21 is controlled by the control unit 50, which will be described later.

[0055] The material supply unit 22 is disposed in the film-forming chamber 15 and supplies the evaporation material M to the receiving section of the evaporation boat 21. The evaporation material M is formed into a wire-shaped component with a wire diameter of, for example, about 2 mm. Although aluminum is used as the evaporation material, it is not limited to this. Examples of evaporation materials include metals such as copper, lithium, tin, and zinc, or their alloys, as well as oxides, nitrides, fluorides, etc. of these metals.

[0056] The material supply unit 22 includes a discharge roller 221 that discharges the linear evaporation material M along its long side. The discharge roller 221 is configured to discharge the evaporation material M continuously at a predetermined speed or intermittently at a predetermined period. The material supply unit 22 is further configured to change the supply position of the evaporation material M relative to the receiving portion 21a of the vapor deposition boat 21, such as... Figure 3 As indicated by the middle arrow A, it can move in the horizontal direction. The supply of evaporation material M by the discharge roller 221 and the horizontal movement of the material supply unit 22 are controlled by the control unit 50, which will be described later.

[0057] (Membrane Delivery Department)

[0058] The film transport unit 30 is disposed in the transport chamber 16. The film transport unit 30 includes: an unwinding roller 31 that continuously releases the film F as a substrate, a take-up roller 32 that continuously retracts the film F released from the unwinding roller 31, and a main roller 33 (transport roller) disposed in the film transport path between the unwinding roller 31 and the take-up roller 32. The film transport unit 30 also includes: a first auxiliary roller 34 disposed upstream of the main roller 33, and a second auxiliary roller 35 disposed downstream of the main roller 33.

[0059] The unwinding roller 31, the take-up roller 32, and the main roller 33 each have a rotation drive unit (not shown in the figure), configured to rotate at a predetermined speed in the direction of the arrow shown in the figure. Thus, the film F is transported within the vacuum chamber 10 from the unwinding roller 31 towards the take-up roller 32 at a predetermined transport speed. Furthermore, the first auxiliary roller 34 and the second auxiliary roller 35 are each composed of free rollers without a rotation drive unit, but are not limited to this; each may also have a rotation drive unit.

[0060] At least a portion of the main roller 33 faces the vapor deposition source 20 through an opening 14a provided in the partition 14. The film F is conveyed to the take-up roller 32 while wound around the outer peripheral surface of the main roller 33 at a predetermined wrap angle, and the surface area exposed to the film formation chamber 15 through the opening 14a is deposited by the vapor deposition source 20. The film F is formed on the outer peripheral surface of the main roller 33 in a continuous manner in the long side direction and is then returned to the take-up roller 32.

[0061] Membrane F is an insulator, and is made of resin films such as OPP (stretched polypropylene) film, PET (polyethylene terephthalate) film, PPS (polyphenylene sulfide) film, and PI (polyimide) film. However, it is not limited to these; membrane F can also be made of metal films such as copper film and aluminum film.

[0062] Furthermore, the film-forming chamber 15 is connected to the exhaust pipe 14. During exhaust, a pressure difference is generated between the film-forming chamber 15 and the transport chamber 16 due to the presence of the partition wall 14. This pressure difference prevents the vapor flow of the evaporating material from entering the transport chamber 16 through the opening 14a.

[0063] Furthermore, although not shown, a gate may be configured between the vapor deposition source 20 (vapor deposition boat 21) and the main roller 33, which can block the vapor flow of the evaporation material M from reaching the film F supported on the main roller 33 from the vapor deposition source 20. For example, by closing the gate at the beginning of film formation until the evaporation of the evaporation material M in the vapor deposition source 20 stabilizes, the evaporation material can be deposited on the film F at a stable film formation rate.

[0064] (Surveillance Department)

[0065] The monitoring unit 40 is used to monitor the evaporation material M supplied to the evaporation boat 21, including a camera unit 41 that acquires images of the molten evaporation material within the containment section 21a of the evaporation boat 21. For example... Figure 1 As shown, the camera unit 41 is disposed on the outside (atmospheric side) of the vacuum chamber 10, and can take pictures of the film-forming chamber 15 through a window 17 made of light-transmitting material provided on a part of the side wall of the vacuum chamber 10.

[0066] In this embodiment, the camera unit 41 includes an infrared camera and a visible light camera. The infrared camera is used to monitor, for example, the area and expansion of the molten liquid Mm within the vapor deposition boat 21, while the visible light camera is used to monitor, for example, the depth of the molten liquid Mm within the vapor deposition boat 21. The image data acquired by the camera unit 41 is output to the control unit 50.

[0067] (Control Department)

[0068] The control unit 50 is a controller that controls the overall operation of the film-forming apparatus 100, including the exhaust pipe 13, the vapor deposition source 20, and the film transport unit 30. The control unit 50 is implemented using computer hardware elements such as CPU (Central Processing Unit), RAM (Random Access Memory), and ROM (Read Only Memory) and necessary software.

[0069] The control unit 50 controls the material supply unit 22 and the power supply circuit 23 based on the output of the monitoring unit 40. More specifically, the control unit 50 includes an image processing unit and a calculation unit, etc. The image processing unit processes the images acquired by the camera unit 41, and the calculation unit calculates the area ratio, area variation rate, or supply speed and supply position of the molten evaporating material M based on the images acquired by the camera unit 41. Alternatively, the image processing unit and the calculation unit may also be included in the monitoring unit 40.

[0070] The control unit 50 is configured to control at least one of the supply speed or supply position of the evaporation material M in the vapor deposition source 20 to the receiving unit 21a, and the power supplied to the vapor deposition boat 21, as detailed below.

[0071] [Research on the occurrence of splash]

[0072] In this type of roll-to-roll film deposition apparatus, it is necessary to maintain a stable deposition rate and suppress the reduction in product yield caused by splashing. However, the frequency of splashing varies significantly with the melting rate and melt volume of the deposition material in the deposition source.

[0073] For example, Figure 4 and Figure 5 As shown, when the depth d of the molten liquid Mm within the containment section 21a of the vapor deposition boat 21 increases, the gas (bubbles) G generated within the molten liquid Mm during heating and evaporation of the material M increases significantly before reaching the molten surface of the molten liquid Mm. This easily leads to larger diameter splashes (splatters) Ms that scatter from the molten surface of the molten liquid Mm directly above the film F. As a result, the shape of the splashes Ms adhering to the film-forming surface of the film F becomes larger, posing a risk of deteriorating the aesthetics and flatness of the film-forming surface. Therefore, it is necessary to adjust the amount of molten liquid Mm in a way that prevents the depth of the molten liquid from becoming excessively large.

[0074] The inventor used in Figure 2 The width W is 45mm, the length L is 150mm, and the volume of the receiving part 21a is 3900mm. 3Aluminum was deposited on film F using a vapor deposition boat sample (hereinafter referred to as vapor deposition boat 21S), and the number of sputtering particles larger than 80 μm per unit area was measured. The shortest distance between vapor deposition boat 21S and film F was 270 mm, and the heating temperature of vapor deposition boat 21S was 1500 °C (power: 28 W). The experimental results showed that when the depth d of the melt was 0.4 mm, the number of sputtering particles per unit area was 62.5 [particles / m]. 2 In contrast, when the depth d is 0.2 mm, it is 1.9 [pieces / m]. 2 This result confirms that when the number of splashes is 10 [pieces / m]. 2 In the case of [ ], the depth d of the melt is preferably less than 0.4 mm, and more preferably less than 0.3 mm.

[0075] In addition, such as Figure 6 As shown, even when the expansion (area) of the molten liquid Mm in the containment section 21a of the vapor deposition boat 21 is small, it can also cause splashing. For example... Figure 7 (A) and (B) schematically illustrate that when the expansion of the molten Mm is small, a large temperature difference easily arises between the areas in contact with and not in contact with the molten Mm in the vapor deposition boat 21. In this state, when the amount of molten Mm varies significantly and the area of ​​molten Mm increases, the molten Mm on the low-temperature side is rapidly heated due to contact with the vapor deposition boat 21 on the high-temperature side, thus easily causing splashing Ms. Therefore, it is necessary to adjust the amount of molten Mm to prevent the expansion of molten Mm from becoming too small.

[0076] Figure 8 The results show the simulated heat distribution of the vapor deposition boat 21S when the area ratio of the molten aluminum to the opening area of ​​the containment portion of the vapor deposition boat 21S is 0%, 33%, 67%, and 99%. Here, the power supply (power: 28W) was adjusted so that the temperature at the center of the vapor deposition boat 21S was 1500°C.

[0077] like Figure 8 As shown, the heat distribution of the 21S vapor deposition boat without molten aluminum exhibits the highest temperature distribution in the center of the boat. On the other hand, when the area ratio of molten aluminum is 33%, the highest temperature distributions occur at two locations on either side of the long side of the center of the boat. Figure 7 The vapor deposition boat 21S shown in (B) is prone to temperature differences within its containment section, thus posing a high risk of splashing. In contrast, when the area ratio of the melt is 67% and 99%, the temperature difference within the containment section can be minimized, thus reducing the risk of splashing.

[0078] Figure 9 This indicates the ratio of molten aluminum (area ratio) to the number of splashes [pieces / m²]. 2An experimental result relating to the relationship between the two. Here, the number of splashes with a size greater than 80 μm is also counted, with the shortest distance between the vapor deposition boat 21S and the film F set at 270 mm, the heating temperature of the vapor deposition boat 21S at 1500 °C (power: 28 W), the depth of the molten liquid d at 0.2 mm, and the supply rate of aluminum (evaporation material M) at 565 mm / min.

[0079] like Figure 9 As shown, there is a tendency for the number of splashes to decrease as the area ratio of the molten liquid increases. It was confirmed that, for example, the number of splashes was stably suppressed to 10 [splashes / m²] in the range of area ratios above 60%. 2 ]the following.

[0080] on the other hand, Figure 10 This represents the rate of change of the molten surface area and the number of splashes (pieces / m²). 2 An experimental result relating the amount of melting at the aluminum tip (the tip of the evaporation material M) to the amount of melting. The number of splashes larger than 80 μm was also counted here, with the shortest distance between the evaporation boat 21S and the film F set at 270 mm, the heating temperature of the evaporation boat 21S at 1500 °C (power: 28 W), and the depth d of the molten liquid at 0.2 mm.

[0081] like Figure 10 As shown, there is a tendency for a higher surface area variation rate of the molten liquid to increase the number of splashes and the amount of aluminum melted at the tip. To suppress this, the target value is 10 [splashes / m]. 2 The number of splashes is below a certain threshold, and the area variation rate of the melt is preferably below 0.07%. To achieve such an area variation rate, the melting amount of the evaporation material M needs to be appropriately adjusted.

[0082] The amount of evaporation material M melted can be adjusted not only by its supply rate but also by its supply position relative to the receiving portion 21a of the vapor deposition boat 21. For example... Figure 11 As shown in (A) to (C), when the top of the evaporating material M is located inside the housing 21a (left side in the figure), in the center, or near the front (right side in the figure), the area T of the evaporating material M receiving radiant heat from the vapor deposition boat 21 is different, thus resulting in differences in the amount of melting. However, even when the amount of melting is high, the supply of molten liquid Mm to the housing 21a is not necessarily high.

[0083] That is, such as Figure 11 As shown in (A), when the top of the evaporating material M is located inside the housing 21a, the area T of radiant heat received by the evaporating material M from the vapor deposition boat 21 increases, and the amount of evaporating material M melted per unit time increases, thus the supply of molten liquid Mm is considered to be high. However, it takes time for the molten liquid Mm to spread to all corners of the housing 21a, and the molten liquid Mm will evaporate in the middle of the spread, thus the supply of molten liquid Mm becomes low.

[0084] On the other hand, such as Figure 11 As shown in (B), when the top of the evaporating material M is located in the center of the housing 21a, the molten liquid Mm can easily spread to all corners of the housing 21a, thus increasing the supply of molten liquid.

[0085] In addition, such as Figure 11 As shown in (C), when the top of the evaporating material M is located near the front side of the housing 21a, the area T of radiant heat received by the evaporating material M from the evaporation boat 21 becomes smaller, and the amount of evaporating material melted per unit time is smaller, so the supply of molten liquid Mm becomes lower.

[0086] Furthermore, a certain correlation was found between the electrical power applied to the vapor deposition boat 21 and the area ratio of the molten liquid Mm, showing a tendency for the area ratio of the molten liquid Mm to decrease as the electrical power increases. This is because when the electrical power increases, the amount of evaporation material M melts increases, but at the same time, the amount of molten liquid Mm evaporates also increases. Therefore, in order to maintain the target area ratio of the molten liquid Mm, the electrical power applied to the vapor deposition boat 21 is preferably below a specified value.

[0087] [Operation of the film-forming device]

[0088] Next, an example of the operation of the film-forming apparatus 100 of this embodiment, configured as described above, will be explained. Figure 12 This is a flowchart illustrating an example of the processing steps performed in the control unit 50.

[0089] When the film-forming apparatus 100 starts operating, the control unit 50 performs pre-film-forming treatment (ST101). Pre-film-forming treatment is a preparatory step before film-forming processing; typical examples include exhaust operation in the vacuum chamber 10, degassing heating treatment for the vapor deposition boat 21, and gate closure. At the end of the pre-film-forming treatment, the control unit 50 performs adjustment processing (ST102-108) of the vapor deposition source 20.

[0090] In the conditioning process of the vapor deposition source 20, firstly, after heating the vapor deposition boat 21 to a temperature higher than the melting point of the vapor deposition material M (e.g., 1500°C), the control unit 50 supplies the vapor deposition material M (ST102) to the vapor deposition boat 21 from the material supply unit 22. The supply location of the vapor deposition material M is not particularly limited, for example, it can be supplied to the center of the receiving section 21a.

[0091] Next, the control unit 50, based on the output of the monitoring unit 40 (camera unit 41), acquires information related to the area of ​​the molten liquid Mm and determines whether the area ratio of the molten liquid Mm to the area of ​​the containment unit 21a is above a predetermined value (ST103). The predetermined value for the area ratio in this embodiment is 60%. This allows for a lower risk of splashing (see reference). Figure 9 ).

[0092] In calculating the area ratio of the molten liquid Mm, images acquired by, for example, an infrared camera in the monitoring unit 40 can be used. In this case, the area ratio of the molten liquid Mm is calculated by comparing the area of ​​the pre-stored molten liquid Mm with the area (opening area) of the receiving portion 21a of the vapor deposition boat 21. The algorithm for calculating this area ratio is not particularly limited, and a machine learning machine can also be used.

[0093] When the control unit 50 determines that the area ratio of the molten liquid Mm is not above a specified value (no in ST103), it adjusts at least one of the supply position, supply speed and electrical power applied to the vapor deposition boat 21 in such a way that the area ratio of the molten liquid Mm is above the specified value (ST104).

[0094] Specifically, methods such as changing the supply position of the evaporating material M, increasing the supply speed of the evaporating material M, and reducing the power supply can be used. Changing the supply position is also effective when the wettability of the molten liquid Mm is poor; in this case, the supply position can be set in the area with poor wettability. In addition, adjusting the power supply can be done by adjusting the current value, adjusting the voltage value, or both (the same applies below).

[0095] Next, the control unit 50, based on the output of the monitoring unit 40 (camera unit 41), acquires information related to the depth d of the molten liquid Mm and determines whether the depth d of the molten liquid Mm is below a predetermined value (ST105). The predetermined value of depth d is not particularly limited as long as it is less than 0.4 mm under the conditions described in the "Study on the Occurrence of Splashing" above; in this embodiment, it is 0.3 mm or 0.2 mm. This allows for a lower risk of splashing.

[0096] As a method for calculating the depth d of the molten metal Mm, images acquired by, for example, a visible light camera in the monitoring unit 40 can be used. In this case, for example... Figure 13 As shown in (A) and (B), the depth d of the molten liquid Mm can be calculated based on the difference (D-d0) between the depth D of the receiving portion 21a of the vapor deposition boat 21, which is determined in advance, and the height d0 from the surface of the molten liquid to the opening edge of the receiving portion 21a, calculated based on an image of the molten liquid Mm after its formation. The algorithm for calculating the depth d is not particularly limited, and a machine learning machine can also be used in this case.

[0097] When the control unit 50 determines that the depth d of the molten liquid Mm is not below a predetermined value (no in ST105), it adjusts at least one of the supply rate of the evaporation material M and the electrical power applied to the vapor deposition boat 21 in such a way that the depth d of the molten liquid Mm is below the aforementioned predetermined value (ST106). Specifically, methods such as reducing the supply rate of the evaporation material M and increasing the electrical power can be cited.

[0098] Next, based on the output of the monitoring unit 40, the control unit 50 acquires information related to the melting amount of the evaporating material M and determines whether the melting amount of the evaporating material M is within the specified range (ST107). As long as the risk of splashing can be suppressed and the melting amount of the molten liquid Mm is less than or equal to a specified value (e.g., 0.3 mm), the above-mentioned specified range is not particularly limited.

[0099] As a method for calculating the melting amount of the evaporating material M, images acquired by, for example, a visible light camera in the monitoring unit 40 can be used. In this case, the melting amount of the evaporating material M can be calculated based on the supply amount or supply rate of the evaporating material M supplied from the material supply unit 22. Alternatively, a machine learning device can also be used in this case.

[0100] Another method for calculating the amount of evaporation material M to be melted can be achieved using images acquired, for example, by an infrared camera in monitoring unit 40. In this case, the amount of evaporation material M to be melted can be calculated based on the change (or rate of change) of the area ratio of the molten liquid Mm per unit time. As for the aforementioned rate of change, under the conditions described in the "study on the occurrence of splashing" above, it is preferably, for example, 0.06% or less (refer to...). Figure 10 Machine learning machines can also be used in this situation.

[0101] When the control unit 50 determines that the melting amount of the evaporation material M is not within the specified range (no in ST107), it adjusts at least one of the supply position of the evaporation material M and the electrical power applied to the vapor deposition boat 21 in such a way that the melting amount of the evaporation material M is within the specified range (ST108). Specifically, methods such as changing the supply position of the evaporation material M or increasing or decreasing the electrical power can be cited.

[0102] If the melting amount of the evaporating material M is within the specified range, the control unit 50 ends the pre-film forming treatment and begins the film forming treatment (ST109). At the beginning of the film forming treatment, the film transport unit 30 is driven and the film F is transported at a specified transport speed, and a gate (not shown) is opened to allow the evaporating particles of the evaporating material M evaporated in the evaporation source 20 to accumulate on the film F on the main roller 33.

[0103] After the film-forming process begins, the control unit 50 repeats the processes ST103 to ST108 described above, thereby controlling the evaporation source 20 (supply position, supply speed, and power of the evaporation material M) (ST110) so that the area ratio of the melt Mm is above a specified value, the depth d of the melt Mm is below a specified value, and the amount of evaporation material melted is within a specified range. This monitoring of the melt Mm is repeated at specified intervals during the film-forming process.

[0104] As described above, according to this embodiment, based on the output of the monitoring unit 40, at least one of the supply speed or supply position of the evaporation material M from the evaporation source 20 to the receiving unit 21a, and the power supplied to the evaporation boat 21 is controlled, thereby maintaining a stable evaporation speed and suppressing the reduction in product yield caused by splashing.

[0105] The above describes the embodiments of the present invention. Of course, the present invention is not limited to the embodiments described, and various modifications can be made.

[0106] Explanation of reference numerals in the attached figures

[0107] 10: Vacuum chamber;

[0108] 20: Evaporation source;

[0109] 21: Steam-plating boat;

[0110] 21a: Containment Department;

[0111] 22: Materials Supply Department;

[0112] 30: Membrane transport section;

[0113] 40: Surveillance Department;

[0114] 41: Camera unit;

[0115] 50: Control Department;

[0116] M: Evaporation material;

[0117] Mm: Molten liquid.

Claims

1. A film forming apparatus, comprising: a vacuum chamber; a conveyance roller disposed inside the vacuum chamber to support a film-like substrate; an evaporation source having an evaporation boat having a housing portion that houses an evaporation material to be evaporated toward the substrate supported by the conveyance roller, and a material supply portion that supplies the evaporation material to the housing portion, the evaporation source melting the evaporation material housed in the housing portion by electrically heating the evaporation boat; a monitoring portion including a camera unit that acquires an image of a molten liquid of the evaporation material in the housing portion; and a control portion that controls at least one of a supply speed or a supply position of the evaporation material in the evaporation source to the housing portion, and an electric power to the evaporation boat, based on an output of the monitoring portion.

2. The film forming apparatus according to claim 1, wherein the control portion acquires information related to an area of the molten liquid based on the output of the monitoring portion, and controls the evaporation source in a manner that a ratio of the area of the molten liquid to an area of the housing portion is equal to or more than a predetermined value.

3. The film forming apparatus according to claim 1, wherein the control portion acquires information related to a depth of the molten liquid based on the output of the monitoring portion, and controls the evaporation source in a manner that the depth of the molten liquid is equal to or less than a predetermined value.

4. The film forming apparatus according to claim 1, wherein the control portion acquires information related to a melting amount of the evaporation material based on the output of the monitoring portion, and controls the evaporation source in a manner that the melting amount of the evaporation material is within a predetermined range.

5. The film forming apparatus according to claim 1, wherein the evaporation material is a linear evaporation material.

6. The film forming apparatus according to claim 1, wherein the camera unit includes an infrared camera and a visible light camera.

7. A control method of a film forming apparatus, the film forming apparatus comprising: a vacuum chamber; a conveyance roller disposed inside the vacuum chamber to support a film-like substrate; and an evaporation source having an evaporation boat composed of a heat generating material and having a housing portion that houses an evaporation material to be evaporated toward the substrate supported by the conveyance roller, and a material supply portion that supplies the evaporation material to the housing portion, the evaporation source melting the evaporation material housed in the housing portion by electrically heating the evaporation boat, in the control method of a film forming apparatus, acquiring a camera image of a molten liquid of the evaporation material in the housing portion, and controlling at least one of a supply speed or a supply position of the evaporation material in the evaporation source to the housing portion, and an electric power to the evaporation boat, based on the camera image. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​

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