Film forming device

Abstract

The film forming apparatus according to the embodiment of the present invention is provided with a film forming chamber for vacuum film forming on a substrate in a decompressed processing container, and a cooling chamber connected to the film forming chamber and cooling the substrate, wherein the cooling chamber comprises: a passage for the substrate to move; and a cooling device, which is arranged on the inner wall of the processing container, and includes a surface area enlarged structure portion opposite to the passage, and a coolant flow path for a coolant. The surface area enlarged structure portion includes a plurality of protrusions protruding from the inner wall of the processing container toward the passage, and the coolant flow path is formed along the protrusions.

Description

Technical Field

[0001] The invention relates to a film forming device. Background Art

[0002] Japanese Patent Publication No. 2003-247067 discloses a vacuum film forming apparatus for forming a film on a substrate arranged in a vacuum container. The vacuum container is provided with a substrate arrangement portion and a film forming material retention portion divided by a baffle 24 that can be opened and closed. The substrate arrangement portion inside the vacuum container is provided with a film forming area for forming a film toward the substrate, and cooling areas arranged at both ends of the film forming area for withdrawing the substrate from the film forming area and performing a cooling process on the substrate.

[0003] In the cooling area, the substrate whose temperature rises due to film formation is clamped between a cooling plate and a clamping plate through which a coolant such as cooling water circulates, and is cooled. In addition, in the (Japanese) Patent Publication No. 2003-247067, it is recorded that a method of pressing a cooling plate against a substrate to cool the substrate and a cooling method based on cooling can be appropriately combined as a cooling method. Summary of the invention

[0004] In the vacuum film forming apparatus disclosed in Japanese Patent Publication No. 2003-247067, the cooling area is provided inside the vacuum container and is in a vacuum state. In a vacuum, the cooling efficiency is lower than that in atmospheric pressure, so it takes time to cool the substrate to a desired temperature. Furthermore, if the length of the cooling chamber is increased in order to increase the residence time of the substrate in the cooling area, the overall size of the device will increase.

[0005] The present invention has been made in view of such a problem, and an object of the present invention is to provide a film forming apparatus capable of improving cooling efficiency.

[0006] One aspect of the present invention involves a film forming device that is provided with a film forming chamber for vacuum film formation on a substrate in a decompressed processing container, and a cooling chamber connected to the film forming chamber and for cooling the substrate, the cooling chamber comprising: a passage for moving the substrate; and a cooling device, which is arranged on the inner wall of the processing container, including a surface area enlarged structure portion opposite to the passage, and a coolant flow path for a coolant.

[0007] On the other hand, the film forming apparatus includes, in a decompressed processing container, a film forming chamber for vacuum film forming on a substrate, and a cooling chamber connected to the film forming chamber and having a higher pressure than that of the film forming chamber for cooling the substrate.

[0008] On the other hand, the film forming device involved is provided with a film forming chamber for vacuum film formation on a substrate in a decompressed processing container, and a cooling chamber connected to the film forming chamber and for cooling the substrate, the cooling chamber comprising: a cooling container filled with a plurality of metal balls made of a material that is the same as or contains the film forming material, and the substrate is held in a state where the substrate is surrounded by the plurality of metal balls; and a cooling device for cooling the cooling container.

[0009] According to the present invention, it is possible to provide a film forming apparatus capable of improving cooling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Hereinafter, features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and wherein:

[0011] Figure 1 This is a diagram showing the structure of a film forming apparatus according to Embodiment 1.

[0012] Figure 2 To show the setting Figure 1 FIG. 1 is a diagram of a first example of a cooling device for a cooling chamber.

[0013] Figure 3 To show the setting Figure 1 FIG. 2 is a diagram of a second example of a cooling device for a cooling chamber.

[0014] Figure 4 To show the setting Figure 1 FIG. 3 is a diagram of a third example of a cooling device for a cooling chamber.

[0015] Figure 5 This is a diagram showing the structure of a film forming apparatus according to the second embodiment.

[0016] Figure 6 This is a diagram showing the structure of a film forming apparatus according to the third embodiment.

[0017] Figure 7 To show the setting Figure 6 A diagram of an example of a cooling container of a cooling chamber.

[0018] Figure 8 It is a graph showing the change in the temperature of the workpiece when the film forming apparatus according to Embodiments 1 to 3 is used. DETAILED DESCRIPTION

[0019] The following describes the embodiments of the present invention with reference to the accompanying drawings. For the purpose of clarity of the description, the following description and drawings are appropriately omitted and simplified. In each of the drawings, the same elements are given the same marks, and repeated descriptions are omitted as needed. It should be noted that the invention involved in the claims is not limited to the following embodiments, and the structures described in the embodiments are not necessarily all necessary for the technical solutions to solve the technical problems.

[0020] Implementation Method 1

[0021] Figure 1 1 is a diagram showing the structure of the film forming device 10 involved in Embodiment 1. The film forming device 10 is a vacuum film forming device that forms a film on a workpiece (substrate) W in a vacuum. As such a vacuum film forming device, there are physical vapor deposition devices such as an ion plating device and a sputtering device, or a chemical vapor deposition device. For example, when a titanium film is formed using a sputtering device, an inert gas (such as argon gas) is introduced into a vacuum chamber (processing container), and a DC voltage is applied between the workpiece and a target material (film forming material Ti) to cause the ionized argon gas to collide with the target material, thereby causing the flying titanium particles to adhere / accumulate on the surface of the workpiece.

[0022] Figure 1 The example shown is an in-line film forming apparatus 10. In the film forming apparatus 10, films are formed simultaneously on a plurality of workpieces W held by a holding member 20. Figure 1 As shown, the film forming apparatus 10 includes film forming chambers 11A and 11B and a cooling chamber 12. Figure 1 As shown by the middle arrow, the film forming chamber 11A, the cooling chamber 12, and the film forming chamber 11B are sequentially arranged from the upstream side along the moving direction of the holder 2. It should be noted that, although not shown here, a load lock chamber or a pre-treatment chamber may be provided at the front section of the film forming chamber 11A, and a post-treatment chamber or a load lock chamber may be provided at the rear section of the film forming chamber 11B.

[0023] The film forming chambers 11A and 11B and the cooling chamber 12 are disposed in the depressurized processing container C. The cooling chamber 12 is communicated with the film forming chambers 11A and 11B. Figure 1 The film is formed on a plurality of workpieces W by moving in the direction indicated by the arrow in FIG. 1 and passing through the film forming chamber 11A and the film forming chamber 11B.

[0024] For example, since the physical vapor deposition device performs the process at a temperature of about 200°C to 600°C, the temperature of the workpiece gradually rises during the film forming process. In an in-line vacuum film forming device, in order to shorten the processing time, multiple evaporation sources 13 are provided or the output power of the evaporation source is increased, so that the temperature rise of the workpiece becomes significant.

[0025] When the workpiece is made of materials such as stainless steel or aluminum, there are problems such as sharpening (corrosion resistance decreases) or softening due to temperature rise, or rigidity decreases due to grain coarsening. In addition, at a high workpiece temperature, film formation on resins and the like becomes difficult. Therefore, time is required to reduce the workpiece temperature before and after the film formation process. The cooling chamber 12 is provided to reduce the temperature of such a workpiece.

[0026] Generally speaking, the cooling chamber is arranged in the same processing container, connected to the film forming chamber, and is in a vacuum state. However, the cooling efficiency of the cooling chamber in a vacuum state is poor, just like a thermos bottle, and it takes time to reduce the temperature of the workpiece W to the specified temperature. Therefore, it is necessary to enlarge (lengthen) the cooling chamber so that the installation area of ​​the processing container (vacuum chamber) containing the cooling chamber becomes larger. Therefore, there is a problem of increased equipment investment costs, that is, increased product processing costs.

[0027] Therefore, the inventors have designed a structure that can improve the cooling efficiency of the cooling chamber 12. The heat transfer methods include (1) radiation, (2) convection, and (3) conduction. The temperature of the workpiece W can be reduced by these three methods alone or in combination. In an embodiment, in an online vacuum film forming device, a cooling chamber 12 using the methods (1) to (3) is provided between the film forming chamber 11A and the film forming chamber 11B. The specific structure of the cooling chamber 12 is described below.

[0028] In the first embodiment, the cooling chamber 12 cools the workpiece W by radiation. Figure 2 It shows that the setting Figure 1 FIG. 1 is a diagram of a first example of a film forming apparatus 10 having a cooling chamber 12. Figure 2 , a diagram showing the film forming apparatus 10 as viewed from above is shown. It should be noted that only the film forming chamber 11A and the cooling chamber 12 are shown here.

[0029] like Figure 2 As shown, two evaporation sources 13 are provided in the film forming chamber 11A. One evaporation source 13 is arranged on the right inner wall and one evaporation source 13 is arranged on the left inner wall in the moving direction of the holder 20.

[0030] The cooling chamber 12 includes a passage 1 and a cooling device 2. In the cooling chamber 12, the cooling device 2 is disposed on the inner wall of the processing container C. Figure 2 In the example shown, the cooling device 2 is disposed on the left and right inner walls, respectively, as viewed from the moving direction of the holder 20. It should be noted that the cooling device 2 may also be disposed on the upper and lower inner walls of the processing container C, or may be disposed on the upper, lower, left, and right sides to surround the passage 1.

[0031] A passage 1 is formed between the cooling devices 2. In the film forming chamber 11A, a holder 20 holding a plurality of workpieces W after film forming process moves to the film forming chamber 11B through the passage 1. The workpieces W pass through the passage 1 and are cooled by the cooling devices 2.

[0032] The cooling device 2 includes a coolant flow path 3, a protruding portion 4, and an extended portion 5. The cooling device 2 circulates a coolant such as cooling water in the coolant flow path 3. The coolant supplied from the outside to one end of the coolant flow path 3 passes through the coolant flow path 3 and is discharged to the outside from the other end thereof. The coolant circulating in the coolant flow path 3 performs heat exchange with the workpiece W, so that the heat of the workpiece W is released to the outside through the coolant, thereby cooling the workpiece W.

[0033] In the cooling device 2, a protrusion 4 and an extension 5 are formed on the surface opposite to the passage 1. The protrusion 4 and the extension 5 constitute a surface area enlargement structure. The protrusion 4 and the extension 5 are provided to enlarge the surface area and thus improve the cooling efficiency of the workpiece W. A plurality of protrusions 4 are provided to protrude from the inner wall of the processing container C toward the passage 1. The coolant flow path 3 is formed in a zigzag manner along the plurality of protrusions 4.

[0034] In this way, the surface area is increased by the surface area enlargement structure, and the coolant flow path 3 is provided along the surface area enlargement structure, so that the effect of absorbing heat from the temperature in the cooling chamber 12 of the cooling device 2 can be improved. As a result, the cooling efficiency of the workpiece W in the cooling chamber 12 can be improved without increasing the length of the equipment.

[0035] The extension portion 5 is formed at the end of the film forming chamber 11A, 11B side of the surface area enlarged structure. The extension portion 5 extends in the direction of reducing the width of the passage 1. That is, the extension portion 5 is higher than the height of the protrusion 4. As a result, the film forming particles from the evaporation source 13 of the film forming chambers 11A, 11B can be collected by the extension portion 5, thereby preventing the film forming particles from adhering to the cooling chamber 12. It should be noted that the surface area enlarged structure can also be a labyrinth structure formed with a maze.

[0036] Figure 3 It is shown that the Figure 1 FIG. 2 is a diagram of a second example of a cooling device for a cooling chamber. Figure 3 In, with Figure 2 The difference is that a foamed metal 6 containing open pores is provided instead of the protrusion 4. The foamed metal 6 containing open pores can increase the surface area. Thus, the cooling capacity of the cooling device 2 can be improved. It should be noted that the foamed metal 6 may also contain closed pores.

[0037] Figure 4 It is shown that the Figure 1 FIG. 3 is a diagram of a third example of a cooling device for a cooling chamber. Figure 4, another example of the protrusion 4 is shown in detail. Figure 4 As shown, the protrusion 4 includes a base 7 and branches 8 .

[0038] The base 7 is a triangular prism having a triangular cross section protruding toward the passage 1. The side surface of the base 7 extends in a direction perpendicular to the moving direction of the holder 20 from the film forming chamber 11A to the cooling chamber 12. The side surface of the protrusion 4 is inclined relative to the surface of the workpiece W. In addition, a plurality of branch portions 8 are provided protruding from the base 7.

[0039] The film forming material M that flies from the film forming chamber 11A and adheres to the inner wall of the cooling chamber 12 will naturally peel off if it is deposited thickly. Figure 4 In the example shown, the side surface of the protrusion 4 is inclined relative to the surface of the workpiece W. Thus, when the film-forming material M peels off, it can be prevented from flying toward the holder 20. Thus, the peeled film-forming material M can be prevented from adhering to the workpiece W, thereby improving the yield.

[0040] In addition, Figure 4 In the example, the surface of the base 7 is formed into a concavo-convex shape by providing the branch portion 8, and the surface is roughened. In this way, by roughening the surface of the protrusion 4, it becomes difficult for the film-forming material M to be peeled off from the surface of the protrusion 4. As a result, the peeling frequency of the film-forming material M is reduced, and the adhesion of the film-forming material M to the workpiece W can be further suppressed. In this way, in the cooling chamber 12, since the film-forming material M after peeling will not adhere to the workpiece W, the smoothing treatment of the formed film can be omitted after film formation. In addition, the negative factors caused by the film-forming material M after peeling, such as the adhesion of the film-forming material M after peeling to the substrate and the defects generated during subsequent peeling, can be reduced.

[0041] As the surface roughening treatment of the protrusion 4, a satin finish may be formed on the surface of the protrusion 4 by sandblasting or the like instead of forming the branch portions 8. In addition, the surface of the protrusion 4 of the first example may be roughened.

[0042] In addition, in the cooling chamber 12, the inner wall and the surface area enlarged structure (the protrusion 4 and the extension 5) of the processing container C facing the workpiece W are preferably black. In this way, if a black material having a black body radiation effect is used, the thermal conductivity of the inner wall and the surface area enlarged structure of the processing container C in the cooling chamber 12 is improved, thereby improving the cooling efficiency of the workpiece W. It should be noted that since the extension 5 captures film-forming particles, the film-forming material (titanium) is sometimes deposited only at this part and appears silver, but the surface other than the part where the film-forming material is deposited can maintain black.

[0043] Implementation Method 2

[0044] In the second embodiment, the cooling chamber 12 cools the workpiece W by convection. Figure 5 1 is a diagram showing the structure of a film forming apparatus 10A according to Embodiment 2. Figure 5 In, with Figure 1 The difference lies in that a pressure regulating chamber 14A is provided between the film forming chamber 11A and the cooling chamber 12 , and a pressure regulating chamber 14B is provided between the cooling chamber 12 and the film forming chamber 11B.

[0045] like Figure 2 As shown in FIG. 1 , the film forming apparatus 10A includes film forming chambers 11A and 11B, a cooling chamber 12 and pressure regulating chambers 14A and 14B. Figure 5 The moving direction of the holder 20 indicated by the middle arrow is sequentially arranged with the film forming chamber 11A, the pressure regulating chamber 14A, the cooling chamber 12, the pressure regulating chamber 14B, and the film forming chamber 11B from the upstream side. The film forming chambers 11A and 11B, the cooling chamber 12, and the pressure regulating chambers 14A and 14B are arranged in the decompressed processing container C. The cooling chamber 12 is connected to the pressure regulating chambers 14A and 14B. The pressure regulating chamber 14A is connected to the film forming chamber 11A, and the pressure regulating chamber 14B is connected to the film forming chamber 11B. The holder 20 is arranged in a manner such that the pressure regulating chamber 14A is connected to the film forming chamber 11A, and the pressure regulating chamber 14B is connected to the film forming chamber 11B. Figure 5 The film is formed on a plurality of workpieces W by moving in the direction indicated by the arrow in FIG. 1 and passing through the film forming chamber 11A and the film forming chamber 11B.

[0046] It should be noted that, although not shown here, a coolant flow path through which a coolant circulates is provided on the inner wall of the processing container C constituting the cooling chamber 12, so that the inner wall of the processing container C itself functions as a cooling device.

[0047] The pressure of the cooling chamber 12 is higher than that of the film forming chambers 11A and 11B. For example, the pressure of the film forming chambers 11A and 11B is 10 - 1 Pa, the pressure in the cooling chamber 12 is 10 3 Pa. For example, an inert gas (a rare gas such as argon or helium, hydrogen, nitrogen, etc.) may be used to make the pressure of the cooling chamber 12 higher than the pressure of the film forming chambers 11A and 11B.

[0048] Thus, by making the pressure of the cooling chamber 12 higher than that of the film forming chambers 11A and 11B, the cooling efficiency can be improved compared to the case where the cooling chamber and the film forming chamber are in the same vacuum state, and the workpiece W can be cooled without increasing the length of the equipment.

[0049] In addition, pressure regulating chambers 14A and 14B are provided between the film forming chambers 11A and 11B and the cooling chamber 12. The pressure of the pressure regulating chambers 14A and 14B is higher than the pressure of the film forming chambers 11A and 11B, and lower than the pressure of the cooling chamber 12. In this way, by providing the pressure regulating chambers 14A and 14B, the pressure in the cooling chamber 12 can be further increased, and the cooling efficiency of the cooling chamber 12 can be further improved.

[0050] Implementation 3

[0051] In the third embodiment, the cooling chamber 12 cools the workpiece W by conduction. Figure 6 This is a diagram showing the configuration of a film forming apparatus 10B according to the third embodiment. Figure 7 It is shown that the Figure 6 FIG. 1 is a diagram of an example of a cooling container of the cooling chamber 12. Figure 6 In, with Figure 1 The difference is that a cooling container 15 for cooling the workpiece W is provided in the cooling chamber 12 .

[0052] The cooling container 15 is provided with a coolant flow path (not shown) through which the coolant circulates, and the wall of the cooling container 15 itself functions as a cooling device. Figure 7 As shown, a plurality of metal balls 16 made of a material (alloy) the same as or containing a film forming material are filled in a cooling container 15. Here, titanium is used as the material of the metal balls 16 in order to form a titanium film.

[0053] It should be noted that the shape of the metal ball 16 does not necessarily have to be spherical, and may be an ellipsoid or slightly deformed. The metal ball 16 is overlapped in multiple layers in the cooling container 15, and gaps are formed between adjacent metal balls 16. The diameter of the metal ball 16 (or the maximum size of the metal ball 16) can be changed in accordance with the shape of the workpiece W. For example, when the workpiece W is provided with a groove, the size of the metal ball 16 can be made larger than the groove (for example, 1 mm).

[0054] The plurality of metal balls 16 may have the same diameter, or may include a plurality of metal balls with different diameters. For example, the plurality of metal balls 16 may include metal balls 16 with diameters of 1 mm, 5 mm, and 10 mm.

[0055] The holder 20 for holding the workpiece W is held in a state surrounded by a plurality of metal balls 16 in the cooling container 15. The plurality of metal balls 16 can move freely in the cooling container 15 without being constrained. Therefore, each metal ball 16 can be freely arranged. As a result, the contact area between the metal ball 16 and the workpiece W can be increased, and the workpiece W can be cooled by heat transfer without increasing the length of the equipment.

[0056] In addition, it is preferable to provide an ultrasonic generator for applying ultrasonic waves to at least one of the cooling container 15 and the holder 20 holding the workpiece W. In a state where ultrasonic waves are applied to at least one of the cooling container 15 and the workpiece W, the workpiece W (substrate) is taken out from the plurality of metal balls 16 or is put into the plurality of metal balls 16. As a result, the resistance when the holder 20 is taken out and put in can be reduced, thereby preventing damage to the workpiece W. In addition, when the holder 20 is taken out from the cooling container 15, the metal balls 16 attached to the holder 20 can be detached.

[0057] Figure 8 This is a diagram showing the change in the workpiece temperature when the film forming apparatus of Embodiments 1 to 3 is used. Two evaporation sources 13 are provided in each of the film forming chambers 11A and 11B. Along the moving direction of the holder 20, the evaporation sources A, B, C, and D are provided in order from the upstream side. It should be noted that when the cooling chamber and the film forming chamber are in the same vacuum state, the example of natural cooling is used as a comparative example.

[0058] like Figure 8 As shown, in each of the first to third embodiments, the temperature of the workpiece W can be lowered more than in the comparative example without increasing the length of the equipment. In addition, the maximum workpiece temperature can be lowered to a temperature lower than the preset target temperature.

[0059] It should be noted that the present invention is not limited to the above-mentioned embodiment, and appropriate changes can be made within the scope of the main purpose. For example, the first embodiment can be combined with the second embodiment, and a cooling device including a surface area expansion structure is provided, and the pressure of the cooling chamber 12 is higher than the pressure of the film forming chambers 11A and 11B. In addition, the embodiment can be combined with the third embodiment, and a cooling container filled with metal balls is provided, and the pressure of the cooling chamber 12 is higher than the pressure of the film forming chambers 11A and 11B.

Claims

1. A film forming apparatus, wherein a film forming chamber for vacuum film forming on a substrate and a cooling chamber connected to the film forming chamber for cooling the substrate are provided in a decompressed processing container, wherein: The cooling chamber has: a passage for movement of the substrate; and a cooling device disposed on the inner wall of the processing container, comprising a surface area enlarged structure portion facing the passage, and a coolant flow path for a coolant, The surface area enlargement structure includes a plurality of protrusions protruding from the inner wall of the processing container toward the passage. The coolant flow path is formed along the protrusion, The protrusion includes a triangular prism-shaped base, the cross section of the base is a triangle protruding toward the passage, and the extension direction of the side surface of the base is perpendicular to the movement direction of the substrate moving from the film forming chamber to the cooling chamber. The protrusion further includes a branch portion protruding from the base portion.

2. The film forming device according to claim 1, wherein: The surface of the protrusion is subjected to a surface roughening treatment.

3. The film forming device according to claim 1, wherein: The surface area enlarged structure includes a foamed metal including open cells.

4. The film forming device according to any one of claims 1 to 3, wherein: An extension portion extending in a direction that reduces the width of the passage is provided at an end portion of the surface area enlarged structure portion on the film forming chamber side.

5. The film forming device according to any one of claims 1 to 3, wherein: The inner wall of the processing container and the surface area enlarged structure in the cooling chamber are black.

6. The film forming device according to any one of claims 1 to 3, wherein: The pressure of the cooling chamber is higher than the pressure of the film forming chamber.

7. The film forming device according to claim 6, wherein: The film forming apparatus further includes a pressure regulating chamber provided between the film forming chamber and the cooling chamber and having a pressure higher than that of the film forming chamber and lower than that of the cooling chamber.

8. The film forming device according to any one of claims 1 to 3, wherein: The cooling chamber also has: a cooling container filled with a plurality of metal balls made of a material that is the same as or contains the film-forming material, and holding the substrate in a state where the substrate is surrounded by the plurality of metal balls; as well as A wall of the cooling vessel is cooled.

9. The film forming device according to claim 8, wherein: The plurality of metal balls include a plurality of metal balls with different diameters.

10. The film forming device according to claim 8, wherein: The film forming device further includes an ultrasonic wave generating device for applying ultrasonic waves to at least one of the cooling container and the substrate. The substrate is taken out of the plurality of metal balls or put into the plurality of metal balls in a state where ultrasonic waves are applied to at least one of the cooling container and the substrate.

Images