Vacuum drying device

Abstract

The present invention provides a technology for suppressing uneven drying of a coating film. A reduced pressure drying device (1) includes a chamber (10), a plurality of support pins (22), and an exhaust section (30). The chamber (10) accommodates a substrate (9). The plurality of support pins (22) support the substrate (9) from below in the chamber (10). The exhaust section (30) exhausts gas in the chamber (10). The plurality of support pins (22) include one or more first support pins (22a) and one or more second support pins (22b) thinner than the first support pins (22a). At least one of the first support pins (22a) supports a peripheral region of the substrate (9) from below. At least one of the second support pins (22b) supports a region of the substrate (9) having a coating film formed therein in an inner region that is closer to the inner side than the peripheral region from below.

Description

Technical Field

[0001] The present disclosure relates to a reduced-pressure drying device. Background Art

[0002] For example, there is known a vacuum drying device for vacuum drying a coating film of a photoresist or the like coated on various substrates. For various substrates, for example, various substrates such as glass substrates, ceramic substrates, semiconductor wafers, electronic component substrates, or printed boards for printing, which are used to form various elements, can be applied. For various elements, for example, semiconductor devices, display panels, solar cell panels, magnetic disks, or optical disks can be applied. For display panels, for example, liquid crystal display panels, organic electroluminescence (EL) display panels, plasma display panels, or field emission displays can be applied.

[0003] When the coating film is dried using a reduced pressure drying device, for example, in a state where a plurality of pins support the substrate in the chamber, the chamber is exhausted from the chamber through the exhaust port at the bottom of the chamber using a vacuum pump. Then, for example, when the vacuum degree reaches a predetermined value, the exhaust from the chamber is stopped, and the chamber is returned to atmospheric pressure by supplying gas into the chamber. For example, an inert gas such as nitrogen or air can be used as the gas.

[0004] In a reduced pressure drying device, for example, if the drying speed of a coating film formed on the upper surface of a substrate varies depending on the location, uneven drying (also referred to as uneven drying) may occur in accordance with the difference in drying speed. Uneven drying may cause, for example, a thickness deviation of the coating film after drying.

[0005] For example, on a substrate, due to the contact of a plurality of pins, a temperature difference may be generated between a portion supported by a plurality of pins and a portion surrounding the portion. Thus, for example, depending on the temperature difference caused by the plurality of pins, a difference may be generated in the drying speed of the coating film. As a result, for example, uneven drying corresponding to the arrangement of the plurality of pins may be generated on the coating film. Here, for example, during the reduced pressure drying of the coating film, although the temperature of the substrate decreases due to the heat of vaporization generated when the solvent, etc., vaporizes from the coating film, the temperature of the plurality of pins is difficult to change regardless of whether the heat capacity of the plurality of pins is large or the plurality of pins are connected to a chamber with a large heat capacity. Therefore, for example, a temperature difference corresponding to the arrangement of the plurality of pins may be generated on the substrate.

[0006] Patent Document 1 describes that a plurality of pins supporting a substrate are hollow pins cooled by discharging a fluid in an inner space or by supplying a liquid such as cooling water into an inner space.

[0007] [Prior art literature]

[0008] [Patent Document]

[0009] [Patent Document 1] Japanese Patent No. 6579773 Summary of the invention

[0010] [Problems to be solved by the invention]

[0011] However, the reduced pressure drying device of Patent Document 1 has a complicated device structure, which results in a high device price. In addition, for example, in a structure in which cooling water is supplied to a hollow pin, leakage of cooling water may adversely affect the vacuum state in the chamber.

[0012] The present disclosure has been made in view of the above-mentioned problems, and an object of the present disclosure is to provide a technology for suppressing occurrence of drying unevenness in a coating film.

[0013] [Technical means to solve the problem]

[0014] The first embodiment is a reduced-pressure drying device for drying a coating film formed on the upper surface of a substrate, the reduced-pressure drying device comprising: a chamber for accommodating the substrate; a plurality of support pins for supporting the substrate from below in the chamber; and an exhaust portion for exhausting gas in the chamber, the plurality of support pins comprising one or more first support pins and one or more second support pins thinner than the first support pins, at least one of the first support pins supporting a peripheral region of the substrate from below, and at least one of the second support pins supporting a region of the substrate, where the coating film is formed, in an inner region that is further inside than the peripheral region from below.

[0015] In a second embodiment of the reduced-pressure drying device according to the first embodiment, the inner region of the substrate is supported only by the second supporting pins.

[0016] In a third embodiment of the reduced-pressure drying device according to the first embodiment, at least another one of the first supporting pins supports a region other than the region where the coating film is formed in the inner region of the substrate.

[0017] In a fourth embodiment of the reduced-pressure drying device according to any one of the first to third embodiments, a contact area between the first support pins and the substrate is larger than a contact area between the second support pins and the substrate.

[0018] In a fifth embodiment of the reduced-pressure drying device according to any one of the first to fourth embodiments, a spacing between the first support pins is wider than a spacing between the second support pins.

[0019] According to the reduced-pressure drying device of any one of the first to fifth embodiments, in a sixth embodiment, the thermal conductivity of the second support pin is 0.12 W / m·K or less.

[0020] In a seventh embodiment of the reduced-pressure drying device according to any one of the first to sixth embodiments, the second support pin is formed of a porous resin.

[0021] [Effects of the Invention]

[0022] According to the first embodiment, at least one of the second support pins supports the area (hereinafter referred to as the first area) in the inner area of ​​the substrate where the coating film is formed from below. Since the second support pins are thin, the amount of rising airflow generated around the second support pins under the reduced pressure of the chamber is small. Therefore, even if the gas rises along the second support pins through the rising airflow and is locally supplied to the lower surface of the first area of ​​the substrate, it is difficult to cause a deviation in the temperature distribution in the first area. Therefore, it is possible to suppress uneven drying of the coating film on the first area.

[0023] According to the second embodiment, even if the number, shape, and position of the region where the coating film is formed in the inner region are changed, the region can be supported by the second support pins.

[0024] According to the third embodiment, the substrate can be supported more firmly.

[0025] According to the fourth embodiment, the horizontal displacement of the substrate relative to the first support pins can be suppressed. On the other hand, the heat transfer between the second support pins and the substrate can be reduced, and the uneven drying of the coating film can be further suppressed.

[0026] According to the fifth embodiment, the number of first support pins can be reduced, so the manufacturing cost of the reduced-pressure drying device can be reduced, and the man-hours for the replacement of the support pins can be reduced.

[0027] According to the sixth and seventh embodiments, the amount of heat transfer between the second support pins and the substrate can be reduced, and the uneven drying of the coating film can be further suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a diagram showing an example of a longitudinal section of a reduced-pressure drying apparatus according to an embodiment.

[0029] Figure 2 This is a diagram showing an example of a cross-section of a reduced-pressure drying apparatus according to an embodiment.

[0030] Figure 3 This is a diagram showing an example of a longitudinal section of a reduced-pressure drying apparatus according to an embodiment.

[0031] Figure 4 It is a perspective view showing an example of a substrate.

[0032] Figure 5This is a diagram showing an example of a longitudinal section of a part of a substrate.

[0033] Figure 6 It is a front view showing an example of the appearance of the first support pin.

[0034] Figure 7 It is a front view showing an example of the appearance of the second support pin.

[0035] Figure 8 This is a diagram showing a first example of the relationship between the coating region of the substrate and the first support pins and the second support pins.

[0036] Fig. 9 This is a diagram schematically showing an example of air flow in a chamber under reduced pressure.

[0037] Fig.10 It is a block diagram conceptually showing functions that can be implemented in the control unit.

[0038] Fig.11 This is a flowchart showing an example of a flow of a reduced-pressure drying process according to one embodiment.

[0039] Fig.12 It is a diagram showing a second example of the relationship between the coating region of the substrate and the first support pins and the second support pins.

[0040] Fig.13 It is a diagram showing a third example of the relationship between the coating region of the substrate and the first support pins and the second support pins.

[0041] Explanation of symbols

[0042] 1: Vacuum drying device

[0043] 9: Substrate

[0044] 9op: outer periphery (side)

[0045] 10: Chamber

[0046] 10s: Inner Space

[0047] 11: Bottom plate

[0048] 11h, 40h: Through hole

[0049] 12: Side wall

[0050] 13: Top plate

[0051] 14: Moving in and out

[0052] 15: Gate part (gate valve)

[0053] 16: Opening and closing drive unit

[0054] 16a, 16b, 16c, 16d: Exhaust port

[0055] 16f: Air supply port

[0056] 20: Support

[0057] 21: Support plate

[0058] 22: Support pin

[0059] 22a: First support pin

[0060] 22b: Second support pin

[0061] 23a: First contact portion

[0062] 23b: Second contact portion

[0063] 25a: First columnar portion

[0064] 25b: Second columnar portion

[0065] 26a: First pedestal

[0066] 26b: Second pedestal

[0067] 27a: First external thread portion

[0068] 27b: Second external thread portion

[0069] 30: Exhaust

[0070] 31: Exhaust pipe

[0071] 31a, 31b, 31c, 31d: Individual piping

[0072] 31e: Main pipe

[0073] 32: Vacuum pump

[0074] 40: Bottom rectifier

[0075] 41: Diagonal

[0076] 50: Side fairing

[0077] 60: Air supply department

[0078] 61: Gas supply piping

[0079] 62: Gas supply

[0080] 70: Pressure gauge

[0081] 80: Control Department

[0082] 81: Opening and closing control unit

[0083] 82: Lifting control unit

[0084] 83: Switching control unit

[0085] 84: Exhaust control unit

[0086] 85: Pump control unit

[0087] 86: Gas supply control department

[0088] 90: Coating film

[0089] 100: Lifting Department

[0090] 100a: Ontology Department

[0091] 100b: Mobile

[0092] 801: Processor

[0093] 802: Memory

[0094] 803: Storage

[0095] 803p:Computer Program (Program)

[0096] 804: Input

[0097] 805: Output

[0098] 806: Ministry of Communications

[0099] 807: Driver

[0100] 807m: Storage medium

[0101] A1: Area (formed area, coating area)

[0102] A2: Area (non-coating area)

[0103] A3: Area (covered area)

[0104] A4: Area (exposed area)

[0105] B1: Peripheral area

[0106] B2: Medial area

[0107] B3: Boundary

[0108] F1: First side

[0109] F2: Second side

[0110] Ga, Gb: Updraft

[0111] H1: descending position

[0112] H2: Ascending position

[0113] S1~S4: Steps

[0114] Va, Vb, Vc, Vd: Individual valves

[0115] Ve: Main valve

[0116] Vf: Air supply valve DETAILED DESCRIPTION

[0117] Hereinafter, an embodiment of the present disclosure and various modified examples are described with reference to the accompanying drawings. In the accompanying drawings, parts having the same structure and function are marked with the same symbols, and repeated descriptions are omitted in the following description. The accompanying drawings are only schematically shown, and the dimensions and positional relationships of the various structures in each figure are not accurately illustrated. In addition, in this specification, the downward direction is the direction of gravity, and the upward direction is the direction opposite to the direction of gravity.

[0118] <1. Structure of vacuum drying device>

[0119] Figure 1 This is a diagram schematically showing an example of a longitudinal section of a reduced-pressure drying apparatus 1 according to an embodiment. Figure 2 This is a diagram schematically showing an example of a cross section of a reduced-pressure drying apparatus 1 according to an embodiment. Figure 3 This is a diagram schematically showing an example of a longitudinal section of a reduced-pressure drying apparatus 1 according to an embodiment. Figure 1 The longitudinal section of Figure 3 The longitudinal sections of FIG. 1 show the structure of the vacuum drying device 1 when viewed from directions that differ by about 90 degrees. Figure 3 In order to avoid complication of the drawings, for the sake of convenience, the structures related to the exhaust unit 30, the air supply unit 60, the pressure gauge 70 and the control unit 80 described later are omitted. The reduced pressure drying device 1 is a device for drying a coating film 90 (see Figure 5 )Drying device.

[0120] For example, a glass substrate, a semiconductor wafer, or a ceramic substrate can be applied to the substrate 9. The substrate 9 has, for example, a first surface F1 (see Figure 4 and Figure 5 ) and a second surface F2 (refer to Figure 5) is a flat substrate. For example, in the reduced pressure drying device 1, the first surface F1 of the substrate 9 is set as the upper surface of the substrate 9, and the second surface F2 of the substrate 9 is set as the lower surface of the substrate 9. Here, it is appropriate to cite a specific example in which a rectangular glass substrate is applied to the substrate 9 for illustration. On the first surface F1 of the substrate 9, for example, a coating film 90 is partially formed by pre-coating a treatment liquid containing an organic material and a solvent. The coating of the treatment liquid is performed, for example, by a slit coater or an inkjet device. For the treatment liquid, for example, a coating liquid such as a liquid containing a polyimide precursor and a solvent (also called a polyimide (PI) liquid) or an anti-etching agent liquid can be applied. For the polyimide precursor, for example, polyamide (Polyamide) acid (Polyamic acid) can be applied. For the solvent, for example, NMP (N-methyl-2-pyrrolidone: N-Methyl-2-Pyrrolidone) can be applied. In addition, for example, when the reduced pressure drying device 1 is applied to the manufacturing process of an organic EL display, the coating film 90 may be dried in the reduced pressure drying device 1 to become a hole injection layer, a hole transport layer or a light-emitting layer of the organic EL display panel.

[0121] Figure 4 It is a perspective view showing an example of the substrate 9 . Figure 5 9 is a diagram showing an example of a longitudinal section of a portion of the substrate 9. Figure 4 As shown, the substrate 9 has, for example, a rectangular shape with different lengths in the vertical and horizontal directions when viewed from above. A plurality of regions A1 for forming elements and the like (also referred to as formed regions and coating regions) are arranged on the substrate 9. Figure 4 In the example, when viewed from above, four rectangular coating areas A1 are arranged in a matrix of two rows and two columns on the substrate 9. However, the shape, number, and arrangement of the coating areas A1 are not limited to the example described above. In the coating process before the vacuum drying process using the vacuum drying device 1, the coating film 90 is formed on the upper surface of each coating area A1 in a desired pattern by a slit coater or an inkjet device. For the desired pattern, for example, a circuit pattern can be applied. Here, for example, Figure 5 As shown, the first surface F1 as the upper surface of each coating area A1 has an area (also referred to as a covered area) A3 covered by the coating film 90 and an exposed area (also referred to as an exposed area) A4 not covered by the coating film 90. In addition, the area around the coating area A1 in the substrate 9 and the area between the adjacent coating areas A1 become areas (also referred to as non-coating areas) A2 where the coating film 90 is not formed on the first surface F1 as the upper surface. The non-coating area A2 is also an exposed area (exposed area) A4 not covered by the coating film 90.

[0122] exist Figure 4In the example, the peripheral area B1 and the inner area B2 in the substrate 9 are also shown. The peripheral area B1 of the substrate 9 is a frame-shaped area that is close to a specified width from the outer peripheral portion (i.e., the side surface) 9op of the substrate 9 to the inner side. The specified width is, for example, less than about 100 mm. Here, the peripheral area B1 of the substrate 9 is equivalent to a part of the non-coated area A2. That is, no elements are formed on the upper surface of the peripheral area B1 of the substrate 9, and here, the coating film 90 is not formed. The inner area B2 of the substrate 9 is an area of ​​the substrate 9 that is closer to the inside than the peripheral area B1. The boundary B3 between the peripheral area B1 and the inner area B2 of the substrate 9 has, for example, a rectangular shape. Here, the inner area B2 of the substrate 9 includes a plurality of coating areas A1, and areas between the plurality of coating areas A1 (in Figure 4 The inner area B2 has, for example, a rectangular shape when viewed from above.

[0123] <<Overview of the structure of the vacuum drying device>>

[0124] First, the structure of the reduced pressure drying device 1 is summarized. Figure 1 and Figure 2 As shown, the reduced pressure drying device 1 includes, for example, a chamber 10, a support portion 20, and an exhaust portion 30. The chamber 10 is a portion for accommodating the substrate 9. The support portion 20 is disposed in the chamber 10 and supports the substrate 9 in a horizontal posture. The so-called horizontal posture mentioned here refers to a posture in which the thickness direction of the substrate 9 is along the up-down direction. The exhaust portion 30 exhausts the gas in the chamber 10 to the outside, thereby reducing the air pressure in the chamber 10. Due to the reduction in the air pressure, the solvent of the coating film 90 evaporates and the coating film 90 is dried.

[0125] In addition, Figure 1 and Figure 2 In the example of , the reduced pressure drying device 1 includes: a lifting unit 100, an air supply unit 60, a control unit 80, a bottom straightening plate 40, a side straightening plate 50, and a pressure gauge 70. The lifting unit 100 lifts and lowers the support unit 20. As a result, the substrate 9 supported by the support unit 20 is also lifted and lowered in the chamber 10. The air supply unit 60 supplies gas into the chamber 10. As a result, the air pressure in the chamber 10 can be restored to atmospheric pressure. The bottom straightening plate 40 and the side straightening plate 50 are arranged in the chamber 10, and adjust the air flow in the chamber 10. The pressure gauge 70 measures the air pressure in the chamber 10 and outputs an electrical signal indicating the measurement result to the control unit 80. The control unit 80 controls various structures of the reduced pressure drying device 1. For example, the control unit 80 controls the exhaust unit 30 based on the air pressure measured by the pressure gauge 70, and adjusts the air pressure in the chamber 10 to the target air pressure.

[0126] Next, a detailed example of each structure of the reduced-pressure drying apparatus 1 will be described.

[0127] <<Chamber 10>>

[0128] The chamber 10 is a portion for accommodating the substrate 9. For the chamber 10, a pressure-resistant container having an internal space 10s for accommodating the substrate 9 can be applied. The chamber 10 is, for example, fixed to an apparatus frame which is not shown in the figure. The shape of the chamber 10 is, for example, a flat rectangular parallelepiped. The chamber 10 has, for example, a substantially square bottom plate portion 11, four side wall portions 12, and a substantially square top plate portion 13. The four side wall portions 12 connect, for example, the four end sides of the bottom plate portion 11 with the four end sides of the top plate portion 13 in the up and down directions. For example, a loading and unloading port 14 and a gate portion (also called a gate valve) 15 for opening and closing the loading and unloading port 14 are provided in one of the four side wall portions 12. The gate portion 15 is, for example, linked to or connected to an opening and closing drive portion 16. In Figure 3 In order to avoid complication of the drawings, the opening and closing drive unit 16 is conceptually shown. For example, a drive mechanism such as a cylinder can be applied to the opening and closing drive unit 16. Here, for example, by the operation of the opening and closing drive unit 16, the gate unit 15 can move between a position (also referred to as a closed position) in which the loading and unloading port 14 is closed and a position (also referred to as an open position) in which the loading and unloading port 14 is opened.

[0129] Here, for example, when the shutter 15 is in the closed position, the internal space 10s of the chamber 10 is sealed. For example, when the shutter 15 is in the open position, the substrate 9 can be carried into and out of the internal space 10s of the chamber 10 through the loading / unloading port 14.

[0130] <<Supporting portion 20>>

[0131] The support portion 20 is a portion that supports the substrate 9 from below in the chamber 10. For example, the support portion 20 is located in the internal space 10s of the chamber 10, and can support the substrate 9 accommodated in the internal space 10s of the chamber 10 from below. The support portion 20, for example, has a plurality of support plates 21 and a plurality of support pins 22. The plurality of support plates 21 are arranged at intervals in the horizontal direction, for example. A plurality of support pins 22 are vertically provided on the upper surface of each support plate 21. The plurality of support plates 21 are portions that serve as a base of the support portion 20. The substrate 9 is, for example, arranged above the plurality of support plates 21, and the upper ends of the plurality of support pins 22 are in contact with the second surface F2 that is the lower surface of the substrate 9, whereby the substrate 9 is supported in a horizontal posture.

[0132] The plurality of support pins 22 include, for example, one or more first support pins 22a and one or more second support pins 22b. In other words, the support portion 20 includes the first support pins 22a and the second support pins 22b that support the substrate 9 from below. Figure 3As shown, the first support pin 22a and the second support pin 22b have a rod-like shape that is long in the up-down direction, and the first support pin 22a is thicker than the second support pin 22b.

[0133] Figure 6 2 is a front view showing an example of the appearance of the first support pin 22a. Figure 7 It is a front view showing an example of the appearance of the second support pin 22b.

[0134] exist Figure 6 In the example of , the first support pin 22a is vertically provided on the upper surface of the first seat portion 26a. That is, the first support pin 22a extends upward from the upper surface of the first seat portion 26a. The first seat portion 26a is formed to be wider than the first support pin 22a. Figure 6 In the example of , a first external thread portion 27a is provided on the lower surface of the first seat portion 26a. The first external thread portion 27a has a columnar shape extending downward from the lower surface of the first seat portion 26a, and a thread tooth is formed on its side. The first support pin 22a is mounted on the upper surface of the support plate 21 by the threading action generated by the first external thread portion 27a. That is, the first external thread portion 27a is combined with the internal thread portion (not shown) formed on the upper surface of the support plate 21 by the threading action, thereby the first support pin 22a is mounted on the upper surface of the support plate 21.

[0135] The pin structure including the first support pin 22a, the first seat portion 26a and the first external thread portion 27a can be formed integrally from the same material, or can be formed by combining a plurality of components. In addition, if the entire pin structure is understood as the first support pin 22a, the portion above the upper surface of the first seat portion 26a can be understood as the first pin body.

[0136] exist Figure 6 In the example, the first support pin 22a includes a first abutment portion 23a and a first columnar portion 25a. The first columnar portion 25a has a columnar shape extending in the up-down direction and is erected on the upper surface of the first pedestal portion 26a. That is, the first columnar portion 25a extends upward from the upper surface of the first pedestal portion 26a. The first columnar portion 25a has, for example, a cylindrical shape. In this case, the shape of the first columnar portion 25a in a horizontal section orthogonal to the up-down direction is circular. For example, the first columnar portion 25a extends in the up-down direction with a constant width. The width (here, the diameter) of the first columnar portion 25a is, for example, set to more than 1 mm, and as a specific example, is set to about 3 mm.

[0137] The first abutting portion 23a is arranged on the upper end surface of the first columnar portion 25a. The first abutting portion 23a has, for example, a cone-shaped shape. As a specific example, the first abutting portion 23a may have a conical shape. Alternatively, the first abutting portion 23a may also have a hemispherical or semi-elliptical shape. In this case, the shape of the horizontal section of the first abutting portion 23a is also circular. The width (here is the diameter) of such a first abutting portion 23a also decreases as it moves upward. The width (here is the diameter) of the lower end of the first abutting portion 23a is, for example, equal to the width (here is the diameter) of the first columnar portion 25a, for example, set to more than 1 mm, and as a more specific example, set to about 3 mm. The upper end (i.e., the vertex) of the first abutting portion 23a abuts against the second surface F2 of the substrate 9.

[0138] As mentioned above, in Figure 6 In the example of , the first support pin 22a has a rod-like shape whose width (here, diameter) decreases monotonically and non-increasingly as it goes upward. Figure 6 In the example of FIG. 5 , the width of the first support pin 22 a is constant in the first columnar portion 25 a regardless of the up-down direction, and decreases monotonically upward in the first contact portion 23 a .

[0139] For the material of the first support pin 22a, for example, a resin material such as polyether ether ketone (PEEK) or polyimide (PI) can be applied. For example, by appropriately adjusting the friction of the resin material, the first support pin 22a can use the friction between the upper end of the first support pin 22a and the second surface F2 of the substrate 9 to support the substrate 9 from below in a manner that the substrate 9 does not shift in the horizontal direction. The first support pin 22a is, for example, a solid material.

[0140] Next, an example of the lengths of the first contact portion 23a and the first columnar portion 25a in the vertical direction will be described. Figure 6 In the example, the length of the first abutment portion 23a is very short compared to the length of the first columnar portion 25a. That is, the first columnar portion 25a is the longest. In other words, the first columnar portion 25a occupies the largest proportion relative to the entirety of the first support pin 22a in the vertical direction. Therefore, the thickness of the first support pin 22a can be represented by the thickness of the first columnar portion 25a. That is, the width (here, the diameter) of the first columnar portion 25a mainly represents the thickness of the first support pin 22a.

[0141] exist Figure 7 In the example, the second support pin 22b is vertically provided on the upper surface of the second seat portion 26b. That is, the second support pin 22b extends upward from the upper surface of the second seat portion 26b. The second seat portion 26b is formed wider than the second support pin 22b. Figure 7In the example, a second external threaded portion 27b is provided on the lower surface of the second seat portion 26b. The second external threaded portion 27b has a columnar shape extending downward from the lower surface of the second seat portion 26b, and a thread tooth is formed on its side. The second support pin 22b is mounted on the support plate 21 by the threading action of the second external threaded portion 27b. The pin structure including the second support pin 22b, the second seat portion 26b and the second external threaded portion 27b can be formed integrally from the same material, or can also be formed by combining multiple components. In addition, if the entire pin structure is understood as the second support pin 22b, the portion above the upper surface of the second seat portion 26b can be understood as the second pin body.

[0142] exist Figure 7 In the example, the second support pin 22b includes a second abutment portion 23b and a second columnar portion 25b. The second columnar portion 25b has a columnar shape extending in the up-down direction and is erected on the upper surface of the second pedestal portion 26b. That is, the second columnar portion 25b extends upward from the upper surface of the second pedestal portion 26b. The second columnar portion 25b has, for example, a cylindrical shape. In this case, the shape of the horizontal section of the second columnar portion 25b is circular. The second columnar portion 25b extends in the up-down direction with equal width, for example. The width (here, the diameter) of the second columnar portion 25b is, for example, set to be greater than 0.6 mm, and as a more specific example, is set to be about 1 mm.

[0143] The second abutting portion 23b is arranged on the upper end surface of the second columnar portion 25b. The second abutting portion 23b has, for example, a cone-shaped shape. As a specific example, the second abutting portion 23b may also have a conical shape. Alternatively, the second abutting portion 23b has a hemispherical or semi-elliptical shape. In this case, the shape of the horizontal section of the second abutting portion 23b is also circular. The width (here is the diameter) of such a second abutting portion 23b also decreases as it moves upward. The width (here is the diameter) of the lower end of the second abutting portion 23b is, for example, equal to the width (here is the diameter) of the second columnar portion 25b, for example, set to more than 0.6 mm, and as a more specific example, set to about 1 mm. The upper end (i.e., the vertex) of the second abutting portion 23b abuts against the second surface F2 of the substrate 9.

[0144] As mentioned above, in Figure 7 In the example of , the second support pin 22b has a rod-like shape whose width (here, diameter) decreases monotonically and non-increasingly as it goes upward. Figure 7 In the example of FIG. 5 , the width of the second support pin 22 b is constant in the second columnar portion 25 b regardless of the up-down direction, and decreases monotonically upward in the second contact portion 23 b .

[0145] As for the material of the second support pin 22b, for example, a resin material such as polyetheretherketone or polyimide can be applied, similarly to the first support pin 22a. The second support pin 22b is, for example, a solid material.

[0146] Next, the lengths of the second contact portion 23b and the second columnar portion 25b in the vertical direction will be described. Figure 7 In the example, the length of the second abutment portion 23b is very short compared to the length of the second columnar portion 25b. That is, the second columnar portion 25b occupies the largest proportion relative to the entirety of the second support pin 22b in the vertical direction. Therefore, the thickness of the second support pin 22b can be represented by the thickness of the second columnar portion 25b. That is, the width (here, the diameter) of the second columnar portion 25b mainly represents the thickness of the second support pin 22b.

[0147] As per Figure 6 and Figure 7 As can be understood from the comparison, the first support pin 22a is thicker than the second support pin 22b. Here, the first columnar portion 25a is thicker than the second columnar portion 25b. The difference between the width (here, diameter) of the first columnar portion 25a and the width (here, diameter) of the second columnar portion 25b can be, for example, 0.5 mm or more, 1 mm or more, or 2 mm or more.

[0148] Here, the comparison between the width of the first support pin 22a and the width of the second support pin 22b in the same horizontal section is further examined. Figure 6 and Figure 7 As shown, in the entirety of the vertical direction of the first support pin 22a and the second support pin 22b, the width of the first support pin 22a in any horizontal section can be greater than the width of the second support pin 22b. For example, the upper portion of the first abutting portion 23a of the first support pin 22a and the second abutting portion 23b of the second support pin 22b can have the same shape. According to the shape, the width of the upper portion of the first abutting portion 23a and the width of the second abutting portion 23b in the horizontal section are equal to each other. On the other hand, the width of the lower portion of the first abutting portion 23a further increases as it goes downward, so in the same horizontal section, the width of the lower portion of the first abutting portion 23a of the first support pin 22a is greater than the width of the second columnar portion 25b of the second support pin 22b. In addition, the width of the first columnar portion 25a is also greater than the width of the second columnar portion 25b in the same horizontal section. According to such a shape, in any horizontal cross section, the first support pin 22a has the same thickness as the second support pin 22b, or is thicker than the second support pin 22b.

[0149] In addition, the comparison of the thickness of the first support pin 22a and the second support pin 22b can also be determined by, for example, comparing the first full circumference length of the profile corresponding to the side of the first support pin 22a and the second full circumference length of the profile corresponding to the side of the second support pin 22b in the same horizontal section. In the above example, the horizontal sections of the first support pin 22a and the second support pin 22b are circular, so the full circumference length is equivalent to the length of the circumference.

[0150] Here, when the horizontal section is moved in the vertical direction, the vertical range in which the first full circumference length is longer than the second full circumference length only needs to account for 50% or more of the vertical length of the first support pin 22a and the second support pin 22b. In this case, it can be said that the first support pin 22a is thicker than the second support pin 22b. The ratio may be, for example, 60% or more, 70% or more, or 80% or more.

[0151] Figure 8 2 is a diagram showing a first example of the positional relationship between the substrate 9 and the first support pins 22a and the second support pins 22b. Figure 8 In the second surface F2 as the lower surface of the substrate 9, the position supported by the first support pin 22a is indicated by a white circle, and the position supported by the second support pin 22b is indicated by a black circle. Figure 8 In FIG. 1 , the outer edge of the coating region A1 in the substrate 9 and the boundary B3 between the peripheral region B1 and the inner region B2 in the substrate 9 are respectively depicted by two-dot chain lines.

[0152] like Figure 8 As shown, a plurality of first support pins 22a support the peripheral region B1 of the substrate 9. That is, the upper ends of these first support pins 22a are in contact with the lower surface of the peripheral region B1 of the substrate 9. The peripheral region B1 of the substrate 9 has a rectangular frame shape when viewed in a plan view, so these first support pins 22a are also arranged along the entire circumference of the rectangular frame. Figure 8 In the example of FIG. 1 , the coating film 90 is not formed on the upper surface of the peripheral region B1 of the substrate 9. That is, the peripheral region B1 corresponds to the non-coating region A2. Figure 8 In the example of , the remaining first support pins 22a are located in an area other than the coating area A1 in the inner area B2 of the substrate 9. That is, the remaining first support pins 22a support the inner area B2 of the substrate 9, but support the non-coating area A2 in the inner area B2. In other words, the upper ends of the remaining first support pins 22a are in contact with the lower surface of the non-coating area A2 in the inner area B2 of the substrate 9.

[0153] On the other hand, the plurality of second support pins 22b support the coating area A1 in the inner area B2 of the substrate 9. That is, the upper ends of the plurality of second support pins 22b are in contact with the lower surface of the coating area A1 of the substrate 9. In the case where a patterned coating film 90 is formed in the coating area A1, some of the second support pins 22b can support the covered area A3 in the coating area A1, and the remaining second support pins 22b can support the exposed area A4 in the coating area A1. In the case where the coating film 90 is formed on the entire coating area A1, the entire coating area A1 is equivalent to the covered area A3, and therefore all the second support pins 22b support the covered area A3.

[0154] As mentioned above, in Figure 8 In the example, all the second support pins 22 b abut against the lower surface of the coating area A1 of the substrate 9 , and all the first support pins 22 a abut against the lower surface of the non-coating area A2 of the substrate 9 .

[0155] Fig. 9 : is a diagram schematically showing an example of the air flow in the chamber 10 under reduced pressure. When the exhaust unit 30 exhausts the gas in the chamber 10, the temperature of the gas in the chamber 10 drops sharply due to adiabatic expansion. The temperature of the gas in the chamber 10 can drop to, for example, about minus (-) 20 degrees Celsius. On the other hand, the temperature of the object (solid) in the chamber 10 also drops. For example, the temperature of the substrate 9 drops due to the absorption of the heat of vaporization accompanying the evaporation of the solvent of the coating film 90 and the heat exchange between the substrate 9 and the surrounding gas. In addition, for example, the temperature of the support pin 22 drops due to the heat exchange between the support pin 22 and the surrounding gas. However, the temperature drop of these objects is not as large as the temperature drop of the gas caused by the adiabatic expansion. For example, the temperature drop of the support pin 22 is about a few degrees (for example, less than about 2 degrees). Therefore, the temperature of the support pin 22 is, for example, about 23 degrees Celsius.

[0156] The gas is heated around the support pin 22 by heat exchange between the support pin 22 and the gas. Therefore, an updraft Ga and an updraft Gb are generated around the first support pin 22a and the second support pin 22b, respectively. The gas rises along the first support pin 22a through the updraft Ga, and the gas rises along the second support pin 22b through the updraft Gb. Therefore, the gas can be locally supplied to the second surface F2 of the substrate 9 through the updraft Ga and the updraft Gb. Therefore, the surrounding of the contact portion with the support pin 22 in the substrate 9 (hereinafter referred to as the pin vicinity region) is more susceptible to the updraft Ga and the updraft Gb than the region away from the pin vicinity region (hereinafter referred to as the pin separation region). As a result, the difference between the temperature of the pin vicinity region and the pin separation region in the substrate 9 becomes larger, and the temperature distribution of the substrate 9 may become uneven.

[0157] In this embodiment, the second support pin 22b is thinner than the first support pin 22a. That is, the second full circumference length of the second support pin 22b in the horizontal section is shorter than the first full circumference length of the first support pin 22a in the horizontal section. In other words, the surface area of ​​the side surface of the second support pin 22b is smaller than the surface area of ​​the side surface of the first support pin 22a. Therefore, the gas around the first support pin 22a exchanges heat with the first support pin 22a with a larger surface area, and the gas around the second support pin 22b exchanges heat with the second support pin 22b with a smaller surface area. Therefore, the rising airflow Ga is generated in a wider range (that is, around the thick first support pin 22a), and the rising airflow Gb is generated in a narrower range (that is, around the thin second support pin 22b). Therefore, the generation amount (for example, volume flow rate) of the rising airflow Gb is smaller than the generation amount of the rising airflow Ga. In Fig. 9 , the thickness of the arrow lines schematically indicates the generation amounts of the updrafts Ga and Gb.

[0158] The second support pin 22b is in contact with the lower surface of the coating area A1 of the substrate 9. Therefore, the gas can be locally supplied to the lower surface of the coating area A1 through the rising airflow Gb around the second support pin 22b. However, the amount of the rising airflow Gb generated is small, so it does not hinder the uniformity of the temperature in the coating area A1 so much. Therefore, compared with the structure in which the first support pin 22a is used as the support pin 22 in contact with the lower surface of the coating area A1, the uniformity of the temperature distribution in the coating area A1 of the substrate 9 can be improved. As a result, the coating film 90 can be dried more evenly. In other words, it is possible to suppress the occurrence of uneven drying in the coating film 90 formed on the upper surface of the substrate 9.

[0159] On the other hand, the first support pin 22a is in contact with the lower surface of the non-coated area A2 of the substrate 9. Therefore, the gas can be locally supplied to the lower surface of the non-coated area A2 of the substrate 9 through the rising airflow Ga. The amount of the rising airflow Ga generated is relatively large, so the temperature distribution in the non-coated area A2 may become uneven compared with the coating area A1. However, in the example, the coating film 90 is not formed in the non-coated area A2, so it is almost impossible to cause poor drying of the coating film 90.

[0160] Moreover, the first support pin 22a is thicker than the second support pin 22b, and therefore has a higher rigidity than the second support pin 22b. Therefore, the first support pin 22a can more firmly support the peripheral area B1 of the substrate 9. For comparison, a structure (hereinafter referred to as a comparative structure) in which a thin second support pin 22b is used in all support pins 22 is examined. In the comparative structure, when an external force is applied to the substrate 9 in the horizontal direction, the substrate 9 can be displaced in the horizontal direction. The reason is that the thinner the support pin 22, the weaker the support pin 22 is against the external force in the horizontal direction. For example, the support pin 22 can be bent with the base portion as the fixed end. When the substrate 9 is moved in and out or when the pressure in the chamber 10 is reduced, an external force with a horizontal component can be applied to the substrate 9, so the substrate 9 can be displaced in the horizontal direction. This displacement of the substrate 9 in the horizontal direction is not preferred.

[0161] In contrast, in the present embodiment, the first support pins 22a supporting the peripheral region B1 of the substrate 9 are thicker than the second support pins 22b supporting the coating region A1 in the inner region B2 of the substrate 9. Therefore, the first support pins 22a can support the peripheral region B1 of the substrate 9 with higher rigidity. Therefore, even if an external force having a horizontal component is applied to the substrate 9, the thick first support pins 22a can effectively suppress the displacement of the substrate 9 in the horizontal direction. Furthermore, if the first support pins 22a are arranged along the entire circumference of the peripheral region B1 of the substrate 9, the peripheral region B1 of the substrate 9 can be supported more firmly, and the displacement of the substrate 9 in the horizontal direction can be more effectively suppressed.

[0162] <<Exhaust section 30>>

[0163] Reference Figure 1 The exhaust part 30 is a part for exhausting the gas in the chamber 10. Figure 1 and Figure 2As shown, four exhaust ports 16a, 16b, 16c, and 16d are provided in the bottom plate 11 of the chamber 10, which is opposite to the substrate 9 in the vertical direction. The exhaust section 30 includes, for example, an exhaust pipe 31, four individual valves Va, Vb, Vc, and Vd, a main valve Ve, and a vacuum pump 32. The exhaust pipe 31 includes, for example, four individual pipes 31a, 31b, 31c, and 31d and one main pipe 31e. For example, one end of the individual pipe 31a is connected to the exhaust port 16a, one end of the individual pipe 31b is connected to the exhaust port 16b, one end of the individual pipe 31c is connected to the exhaust port 16c, and one end of the individual pipe 31d is connected to the exhaust port 16d. For example, the other ends of the four individual pipes 31a, 31b, 31c, and 31d merge and are connected to one end of the main pipe 31e. For example, the other end of the main pipe 31e is connected to the vacuum pump 32. For example, the individual valve Va is provided on the path of the individual pipe 31a, the individual valve Vb is provided on the path of the individual pipe 31b, the individual valve Vc is provided on the path of the individual pipe 31c, and the individual valve Vd is provided on the path of the individual pipe 31d. For example, the main valve Ve is provided on the path of the main pipe 31e.

[0164] Here, for example, when at least one of the four individual valves Va, Vb, Vc, and Vd and one main valve Ve are opened and the vacuum pump 32 is operated while the loading and unloading port 14 is closed by the gate portion 15, the gas in the chamber 10 is exhausted to the outside of the chamber 10 through the exhaust pipe 31. As a result, for example, the gas pressure of the internal space 10s of the chamber 10 can be reduced. The four individual valves Va, Vb, Vc, and Vd are, for example, valves for adjusting the exhaust volume from the four exhaust ports 16a, 16b, 16c, and 16d, respectively. For example, a valve (also referred to as an on-off valve) that switches between an open state and a closed state based on a command from the control portion 80 can be applied to each of the four individual valves Va, Vb, Vc, and Vd. The main valve Ve is, for example, a valve for adjusting the total exhaust volume from the four exhaust ports 16a, 16b, 16c, and 16d. As the main valve Ve, for example, a valve whose opening degree can be adjusted based on a command from the control unit 80 (also referred to as an opening control valve) can be applied.

[0165] <<Lifting unit 100>>

[0166] The lifting unit 100 is a part that moves the support unit 20 up and down in the chamber 10. In other words, for example, the lifting unit 100 has a mechanism (also referred to as a lifting mechanism) that can move the support unit 20 up and down. Figure 1 In order to avoid complication of the drawings, the lifting unit 100 is conceptually shown. For example, a driving device such as a direct-acting motor or a cylinder can be applied to the lifting unit 100. Figure 3As shown, the lifting part 100, for example, has a main body 100a and a moving part 100b. The main body 100a is, for example, fixed to an apparatus frame (not shown) outside the chamber 10. The moving part 100b can, for example, move in the up-down direction relative to the main body 100a. For the moving part 100b, for example, a rod-shaped member or the like can be applied. The moving part 100b, for example, exists in a state of being inserted into a through hole 11h of the bottom plate part 11 of the chamber 10. Moreover, for example, a support part 20 is fixed to the upper end part of the moving part 100b. Here, for example, if a bellows or the like is provided between the lower surface of the bottom plate part 11 and the moving part 100b, the gap between the bottom plate part 11 and the moving part 100b can be sealed. For example, in the case where the support portion 20 has a plurality of support plates 21, the movable portion 100b has a rod-shaped portion (also referred to as a rod-shaped portion) fixed to the support plate 21 for each support plate 21 and inserted into the through hole 11h of the bottom plate portion 11, a portion connecting the plurality of rod-shaped portions (also referred to as a connecting portion), and a portion (also referred to as a sliding portion) connected to the connecting portion and slidably supported on the main body portion 100a.

[0167] Here, for example, when the lifting unit 100 is operated, the support unit 20 is at the lowered position H1 ( Figure 1 and Figure 3 The position indicated by the dotted line) is higher than the ascending position H2 ( Figure 1 and Figure 3 In this case, for example, a plurality of support plates 21 can be lifted and lowered in an integrated manner.

[0168] <<Bottom straightening plate 40>>

[0169] The bottom straightening plate 40 is a plate for limiting the flow of gas in the internal space 10s when the chamber 10 is depressurized by the exhaust unit 30. For example, the bottom straightening plate 40 is arranged between the substrate 9 supported by the support unit 20 and the bottom plate 11 of the chamber 10. The bottom straightening plate 40 is fixed to the bottom plate 11 of the chamber 10 via a plurality of support pillars (not shown). Figure 2 As shown, for example, the bottom straightening plate 40 has a square shape when viewed from above. Moreover, for example, the length of each side of the bottom straightening plate 40 when viewed from above is longer than any of the long side and the short side of the rectangular substrate 9. Therefore, for example, regardless of the orientation of the substrate 9 arranged on the support portion 20, the bottom straightening plate 40 is larger than the substrate 9 when viewed from above. In addition, the bottom straightening plate 40 has, for example, a through hole 40h in a state in which the moving portion 100b of the lifting portion 100 is inserted. In the through hole 40h, the bottom straightening plate 40 and the moving portion 100b exist with a very small gap.

[0170] <<Side fairing 50>>

[0171] The side straightening plates 50 are plates used together with the bottom straightening plates 40 to restrict the flow of gas in the internal space 10s when the chamber 10 is depressurized by the exhaust portion 30. For example, the side straightening plates 50 are arranged between the substrate 9 supported by the support portion 20 arranged at the lowered position H1 and the side wall portion 12 of the chamber 10. Here, for example, four side straightening plates 50 are arranged so as to surround the periphery of the substrate 9 supported by the support portion 20. For example, the four side straightening plates 50 form a square cylindrical straightening plate surrounding the substrate 9 as a whole. In addition, for example, the bottom straightening plate 40 and the four side straightening plates 50 form a bottom cylindrical box-shaped straightening plate as a whole.

[0172] Here, for example, when the pressure in the chamber 10 is reduced by the exhaust unit 30, the gas in the internal space 10s of the chamber 10 is discharged to the outside of the chamber 10 through the space between the side rectifying plate 50 and the side wall portion 12, the space between the bottom rectifying plate 40 and the bottom plate portion 11, and the exhaust ports 16a, 16b, 16c, and 16d in the order described above. In this way, for example, the gas flows in the space away from the substrate 9, and it is difficult to form an airflow near the substrate 9. In addition, it is difficult to generate a concentrated airflow around the peripheral portion of the substrate 9. As a result, for example, it is possible to suppress the occurrence of uneven drying of the coating film 90 formed on the upper surface of the substrate 9.

[0173] In addition, here, for example, Figure 2 As shown in FIG. 1 , a structure is adopted in which the four exhaust ports 16a, 16b, 16c, and 16d are all located on the diagonal line 41 of the square bottom face rectifying plate 40 in a plan view. In this case, for example, symmetrical airflows with respect to the center (intersection of the two diagonal lines 41) of the bottom face rectifying plate 40 can be formed through the exhaust ports 16a, 16b, 16c, and 16d. As a result, for example, a more uniform airflow can be formed in the internal space 10s of the chamber 10.

[0174] <<Air supply unit 60>>

[0175] The gas supply unit 60 is a part that performs the operation of supplying gas into the chamber 10 (also referred to as gas supply). Figure 1 As shown, the bottom plate portion 11 of the chamber 10 is provided with, for example, an air supply port 16f. The air supply port 16f is, for example, located below the bottom face rectifying plate 40. The air supply portion 60 includes an air supply pipe 61 connected to the air supply port 16f, an air supply valve Vf, and an air supply source 62. For example, one end of the air supply pipe 61 is connected to the air supply port 16f. For example, the other end of the air supply pipe 61 is connected to the air supply source 62. For example, the air supply valve Vf is provided on the path of the air supply pipe 61.

[0176] Here, for example, when the gas supply valve Vf is opened, gas is supplied from the gas supply source 62 to the internal space 10s of the chamber 10 via the gas supply pipe 61 and the gas supply port 16f. As a result, the gas pressure in the chamber 10 can be increased. The gas supplied from the gas supply source 62 can be, for example, an inert gas such as nitrogen or clean dry air. The clean dry air can be prepared by, for example, purifying the air in a general environment to remove particles and moisture.

[0177] <<Pressure gauge 70>>

[0178] The pressure gauge 70 is a sensor for measuring the air pressure of the internal space 10s of the chamber 10. Figure 1 As shown, for example, the pressure gauge 70 is installed in a part of the chamber 10. The pressure gauge 70 can measure the pressure of the internal space 10s of the chamber 10, for example, and output the measurement result to the control unit 80.

[0179] <<Control unit 80>>

[0180] The control unit 80 is a unit for controlling the operation of each part of the reduced pressure drying device 1. For example, the control unit 80 can control the exhaust unit 30, the air supply unit 60, and the lifting unit 100. The control unit 80 includes, for example, a computer having a processor 801 such as a central processing unit (CPU), a memory 802 such as a random access memory (RAM), and a storage unit 803 such as a hard disk drive. In the storage unit 803, for example, a computer program (also referred to as a program) 803p and various data for performing a process (also referred to as a reduced pressure drying process) of drying the coating film 90 on the substrate 9 by reducing pressure in the reduced pressure drying device 1 are stored. The storage unit 803, for example, stores the program 803p and has a function as a non-temporary storage medium that can be read by a computer. The control unit 80, for example, reads the program 803p and data from the storage unit 803 to the memory 802, and performs arithmetic processing according to the program 803p and data in the processor 801, thereby controlling the operation of each part of the reduced pressure drying device 1. Therefore, for example, the program 803 p can execute the reduced-pressure drying process by being executed by the processor 801 included in the control unit 80 in the reduced-pressure drying apparatus 1 .

[0181] In addition, the control unit 80 may be connected to, for example, an input unit 804, an output unit 805, a communication unit 806, and a driver 807. The input unit 804 is, for example, a part that inputs various signals to the control unit 80 in response to the user's actions. The input unit 804 may include, for example, an operation unit that inputs signals corresponding to the user's operations, a microphone that inputs signals corresponding to the user's voice, and various sensors that input signals corresponding to the user's movements. The output unit 805 is, for example, a part that outputs various information in an embodiment that the user can recognize. The output unit 805 may include, for example, a display unit, a projector, and a speaker. The display unit may also be a touch screen integrated with the input unit 804. The communication unit 806 is, for example, a part that sends and receives various information to and from an external device such as a server through a wired or wireless communication component. For example, a program 803p received from an external device through the communication unit 806 may also be stored in the storage unit 803. The driver 807 is, for example, a part that can load and unload a removable storage medium 807m such as a magnetic disk or an optical disk. The driver 807, for example, performs data transmission between the storage medium 807m and the control unit 80 when the storage medium 807m is installed. For example, the storage medium 807m storing the program 803p may be installed in the driver 807, and the program 803p may be read from the storage medium 807m and stored in the storage unit 803. Here, the storage medium 807m, for example, stores the program 803p and serves as a non-temporary storage medium that can be read by a computer.

[0182] Fig.10 80 is a block diagram conceptually showing the functions implemented in the control unit 80. Fig.10 As shown, the control unit 80 is electrically connected to, for example, the opening and closing drive unit 16, the lifting unit 100, the four individual valves Va, Vb, Vc, and Vd, the main valve Ve, the vacuum pump 32, the air supply valve Vf, and the pressure gauge 70. The control unit 80 can control the operation of each of the above-mentioned parts by referring to the measured value output from the pressure gauge 70, for example.

[0183] like Fig.10As conceptually shown in FIG. 8 , the control unit 80 has, for example, an opening and closing control unit 81, a lifting control unit 82, a switching control unit 83, an exhaust control unit 84, a pump control unit 85, and an air supply control unit 86 as functional structures implemented. For example, the opening and closing control unit 81 controls the operation of the opening and closing drive unit 16. For example, the lifting control unit 82 controls the operation of the lifting unit 100. For example, the switching control unit 83 controls the opening and closing states of four individual valves Va, Vb, Vc, and Vd individually. For example, the exhaust control unit 84 controls the opening and closing state and the opening degree of the main valve Ve. For example, the pump control unit 85 controls the operation of the vacuum pump 32. For example, the air supply control unit 86 controls the opening and closing state of the air supply valve Vf. The functions of each part of the control unit 80 are implemented, for example, by the processor 801 performing calculation processing according to the program 803p, etc.

[0184] <2. Reduced pressure drying treatment>

[0185] Next, the reduced-pressure drying process of the substrate 9 using the reduced-pressure drying apparatus 1 will be described. Fig.11 80 is a flowchart showing an example of a process of a reduced pressure drying process according to an embodiment. The process of the reduced pressure drying process is implemented, for example, by executing a program 803p in a processor 801 included in a control unit 80. Here, for example, the process is performed in the order described above. Fig.11 The processing of steps S1 to S4.

[0186] When the reduced pressure drying device 1 is used to perform the reduced pressure drying treatment, for example, first, the substrate 9 is carried into the chamber 10 (step S1). At this time, the substrate 9 is in a state where an undried coating film 90 is formed on the upper surface of the substrate 9. In step S1, for example, the gate unit 15 opens the loading and unloading port 14 under the control of the control unit 80, and the transport robot (not shown) carries the substrate 9 on the fork-shaped manipulator and carries the substrate 9 into the internal space 10s of the chamber 10 through the loading and unloading port 14 of the chamber 10. At this time point, the support unit 20 is configured at the descending position H1, for example. The transport robot, for example, carries the substrate 9 on the support unit 20 while inserting the fork-shaped manipulator between the plurality of support plates 21 of the support unit 20, and then retracts the fork to the outside of the chamber 10. Then, the gate unit 15 closes the loading and unloading port 14 under the control of the control unit 80. As described above, in step S1 , a process (also referred to as a placing process) of placing the substrate 9 on the plurality of support pins 22 arranged in the chamber 10 is performed.

[0187] In step S1, the substrate 9 is supported by a plurality of support pins 22. Specifically, the peripheral area B1 of the substrate 9 is supported by the first support pins 22a, and the coating area A1 in the inner area B2 of the substrate 9 is supported by the second support pins 22b. In addition, the non-coating area A2 in the inner area B2 of the substrate 9 is supported by the first support pins 22a.

[0188] Next, the reduced pressure drying device 1 exhausts the gas in the chamber 10 (step S2). Specifically, the control unit 80 causes the exhaust unit 30 to exhaust the gas in the chamber 10, thereby reducing the pressure in the chamber 10. In other words, in step S2, a process of reducing the pressure in the chamber 10 (also referred to as an exhaust process) is performed. Through the exhaust process, the gas pressure in the chamber 10 drops to the target gas pressure.

[0189] In step S2, for example, the control unit 80 may appropriately raise and lower the support unit 20, may appropriately control the opening and closing states of each of the plurality of individual valves Va, Vb, Vc, and Vd, or may appropriately control the opening degree of the main valve Ve. For example, the reduced pressure drying device 1 may also slowly exhaust the gas in the chamber 10 while moving the support unit 20 to the ascending position H2 at the beginning of the exhaust process (first process), and then, after moving the support unit 20 to the descending position H1, the exhaust unit 30 rapidly exhausts the gas in the chamber 10 (second process). Thus, the chamber 10 can be decompressed while suppressing the generation of a strong airflow around the substrate 9 in the chamber 10.

[0190] Thereafter, the exhaust unit 30 exhausts the gas in the chamber 10 in such a manner that the gas pressure in the chamber 10 is the target gas pressure and is substantially constant (third process). When the gas pressure reaches the target gas pressure, the solvent in the coating film 90 boils and the coating film 90 is dried at a higher speed. When the boiling of the coating film 90 ends, the exhaust unit 30 may further reduce the pressure in the chamber 10 (fourth process). Thus, the coating film 90 can be dried more reliably.

[0191] In addition, due to the exhaust of the gas in the chamber 10, the temperature of the gas in the chamber 10 drops sharply, and the temperature of each object in the chamber 10 also drops to a certain extent. Therefore, as described above, an updraft Ga and an updraft Gb are generated around the first support pin 22a and around the second support pin 22b in the chamber 10, respectively. However, the amount of the updraft Gb generated is smaller than the updraft Ga, so the deviation of the temperature distribution of the coating area A1 of the substrate 9 caused by the updraft Gb is small. Therefore, the generation of uneven drying caused by the deviation of the temperature distribution of the substrate 9 can be suppressed.

[0192] In addition, in the exhaust process, the control unit 80 may cause uneven drying of the coating film 90 through the airflow between the upper surface of the substrate 9 and the top plate portion 13. In order to suppress the occurrence of the uneven drying, the open and closed states of the four individual valves Va, Vb, Vc, and Vd may be switched in sequence in each of the first to third processes. For example, the switching control unit 83 closes one of the four individual valves Va, Vb, Vc, and Vd, and opens the other individual valves. Moreover, the switching control unit 83 sequentially changes the closed individual valve. Specifically, the first state in which one individual valve Va is closed and the other three individual valves Vb, Vc, and Vd are opened, the second state in which one individual valve Vb is closed and the other three individual valves Va, Vc, and Vd are opened, the third state in which one individual valve Vc is closed and the other three individual valves Va, Vb, and Vd are opened, and the fourth state in which one individual valve Vd is closed and the other three individual valves Va, Vb, and Vc are opened are switched in sequence. In this way, in the exhaust process, the direction of the airflow in the space formed between the upper surface of the substrate 9 and the top plate 13 changes according to the switching of the individual valves Va, Vb, Vc, and Vd. Therefore, the coating film 90 on the upper surface of the substrate 9 can be dried more uniformly. On the other hand, in the fourth process, since the evaporation of the solvent is not active, all four individual valves Va, Vb, Vc, and Vd can be opened.

[0193] Next, the control unit 80 opens the gas supply valve Vf. Thus, gas is supplied from the gas supply source 62 through the gas supply pipe 61 and the gas supply port 16f to the internal space 10s of the chamber 10 (step S3). Thus, the gas pressure in the chamber 10 rises to atmospheric pressure again.

[0194] Then, for example, the substrate 9 is finally carried out of the chamber 10 (step S4). In step S4, for example, first, the gate unit 15 opens the loading / unloading port 14 under the control of the control unit 80, and the transport robot (not shown) carries the dried substrate 9 placed on the support unit 20 out of the chamber 10 through the loading / unloading port 14 of the chamber 10. In this way, the reduced pressure drying process for one substrate 9 can be completed.

[0195] Thus, the method of drying the coating film 90 formed on the first surface F1 which is the upper surface of the substrate 9 using the reduced-pressure drying apparatus 1 (also referred to as a reduced-pressure drying method) includes, for example, a placing step and an exhaust step.

[0196] As described above, in the reduced pressure drying device 1 of one embodiment, in step S1, the substrate 9 is placed on the first support pins 22a and the second support pins 22b. The first support pins 22a are thicker than the second support pins 22b. Figure 8In the example, a plurality of first support pins 22a support the peripheral region B1 of the substrate 9, and the second support pins 22b support the coating region A1 in the inner region B2 of the substrate 9. The thick first support pins 22a support the peripheral region B1 of the substrate 9, so that, for example, in the exhaust process, even if an external force with a horizontal component is applied to the substrate 9 due to the airflow, the displacement of the substrate 9 in the horizontal direction can be more reliably suppressed.

[0197] On the other hand, the amount of the rising airflow Ga around the first support pin 22a generated in the exhaust process is relatively large. Therefore, the uniformity of the temperature distribution in the peripheral area B1 can be reduced. However, since the coating film 90 is not formed in the peripheral area B1, it hardly causes uneven drying.

[0198] The second support pins 22b supporting the coating area A1 of the substrate 9 are thin, so the amount of the rising airflow Gb generated around the second support pins 22b generated in the exhaust process can be reduced. Therefore, the rising airflow Gb can be suppressed from supplying gas to the lower surface of the coating area A1 of the substrate 9. Therefore, the deviation of the temperature distribution in the coating area A1 can be reduced, and the occurrence of uneven drying of the coating film 90 can be suppressed.

[0199] As described above, according to the reduced-pressure drying apparatus 1 of one embodiment, it is possible to achieve both suppression of displacement in the horizontal direction of the substrate 9 and suppression of deviation in the temperature distribution in the coating area A1.

[0200] In addition, Figure 8 In the example of FIG. 1 , the non-coated area A2 in the inner area B2 of the substrate 9 is supported by the thick first support pins 22a. Thus, the substrate 9 can be supported more firmly.

[0201] <<Number of support pins>>

[0202] As described above, the thick first support pins 22a can suppress the horizontal displacement of the substrate 9. Therefore, regarding the second support pins 22b, the number of the second support pins 22b can be determined by considering only the strength in the buckling direction. For example, the buckling load Pcr of the support pins 22 can be expressed by the following formula.

[0203] [Number 1]

[0204]

[0205] Here, E represents Young's modulus, Imin represents the minimum value of the secondary moment of section, and L represents the length of the support pin 22 .

[0206] For example, when the diameter is 0.5 mm, the Young's modulus is 4300 MPa, and the length of the support pin 22 is 30 mm, the buckling load Pcr is about 0.29 N. As long as the weight of the substrate 9 applied to each second support pin 22 b is less than the buckling load Pcr, in order to support a substrate 9 with a thickness of 0.5 mm and a specific gravity of 3 g / cm 3 For the substrate 9, one second supporting pin 22b is required every 130 mm.

[0207] <<Arrangement example of support pin>>

[0208] exist Figure 8 In the example, the first support pin 22a abuts against the lower surface of the non-coating area A2 of the substrate 9, and the second support pin 22b abuts against the lower surface of the coating area A1 of the substrate 9. It can also be said that the coating area A1 is a component area for forming components, so it can also be said that the first support pin 22a abuts against the lower surface of the non-component area of ​​the substrate 9, and the second support pin 22b abuts against the component area of ​​the substrate 9. However, it is not necessarily limited to this.

[0209] Fig.12 2 is a diagram showing a second example of the positional relationship between the substrate 9 and the first support pins 22a and the second support pins 22b. Fig.12 In the example of , all the first support pins 22a abut against the lower surface of the peripheral area B1 of the substrate 9, and all the second support pins 22b abut against the lower surface of the inner area B2 of the substrate 9. On the contrary, all the first support pins 22a do not abut against the lower surface of the inner area B2 of the substrate 9, but are arranged to avoid the inner area B2 of the substrate 9. Similarly, all the second support pins 22b do not abut against the lower surface of the peripheral area B1 of the substrate 9, but are arranged to avoid the peripheral area B1 of the substrate 9.

[0210] Accordingly, the thick first support pins 22a are not located directly below the inner area B2 of the substrate 9. Therefore, even if the number, position, and shape of the coating area A1 are changed in the inner area B2 of the substrate 9, the coating area A1 of the substrate 9 is supported only by the thin second support pins 22b. Therefore, the area on which the coating film 90 is formed in the substrate 9 is supported only by the second support pins 22b. Therefore, even if the number, position, and shape of the coating area A1 are changed, the occurrence of uneven drying of the coating film 90 can be suppressed.

[0211] <<Contact area between support pin 22 and substrate 9>>

[0212] There is no particular limitation on the size relationship between the first contact area between the upper end of the first support pin 22a and the second surface F2 as the lower surface of the substrate 9 and the second contact area between the upper end of the second support pin 22b and the second surface F2 of the substrate 9. However, the first contact area of ​​the first support pin 22a with respect to the peripheral area B1 of the supporting substrate 9 may be larger than the second contact area.

[0213] Accordingly, the friction force between the first support pins 22a and the peripheral area B1 of the substrate 9 can be made greater than the friction force between the second support pins 22b and the substrate 9. Therefore, the thicker first support pins 22a can reduce the horizontal displacement of the substrate 9. On the other hand, if the first contact area is large, the amount of heat transferred between the first support pins 22a and the substrate 9 is relatively large. However, these first support pins 22a support the peripheral area B1 of the substrate 9 (i.e., the non-coating area A2), and therefore are not likely to cause deviations in the temperature distribution in the coating area A1 of the substrate 9.

[0214] The second contact area between the second support pin 22b and the substrate 9 is smaller than the second contact area between the first support pin 22a and the substrate 9, so that the amount of heat transferred between the second support pin 22b and the substrate 9 can be reduced. Although the second support pin 22b supports the coating area A1 of the substrate 9, the amount of heat transferred between the second support pin 22b and the substrate 9 is small, so the deviation of the temperature distribution of the coating area A1 can be suppressed. Therefore, the occurrence of uneven drying of the coating film 90 can be suppressed.

[0215] <<Pitch of support pins 22>>

[0216] Next, the pitch between the first support pins 22 a and the pitch between the second support pins 22 b will be described. Fig.13 2 is a diagram showing a third example of the positional relationship between the substrate 9 and the first support pins 22a and the second support pins 22b. Fig.13 In the example, the intervals between the first support pins 22a are wider than the intervals between the second support pins 22b.

[0217] The first support pins 22a are thicker than the second support pins 22b, so even if the intervals between the first support pins 22a are set wider than the intervals between the second support pins 22b, the substrate 9 can be properly supported. Conversely, within the range of the extent to which the substrate 9 can be properly supported while suppressing displacement in the horizontal direction of the substrate 9, the intervals between the first support pins 22a can be set wider than the intervals between the second support pins 22b.

[0218] According to this, the number of the first support pins 22a can be reduced, and the manufacturing cost of the reduced pressure drying device 1 can be reduced. In addition, the upper end of the support pin 22 can be worn due to contact with the substrate 9. That is, the support pin 22 is a consumable part, so the support pin 22 needs to be replaced, but the fewer the number of the support pins 22, the less man-hours for the replacement operation of the support pins 22 can be.

[0219] <<Material of the support pin 22>>

[0220] The second support pin 22b can be formed of a porous resin, for example. The so-called porous resin mentioned here refers to a structure containing a plurality of pores inside the resin. Such a porous resin can be manufactured, for example, by foaming such as supercritical foaming. For example, polypropylene can be applied to the resin. The average value of the diameter of the pores formed inside the resin can be, for example, more than a few nm or less than tens of μm.

[0221] The thermal conductivity of the second support pin 22b is relatively low. This is because the gas in the pores is less likely to transfer heat than the resin, so the movement of heat in the second support pin 22b is hindered by the pores. The thermal conductivity of the second support pin 22b may be, for example, 0.12 W / m·K or less.

[0222] If the thermal conductivity of the second support pin 22b is small, the amount of heat that moves between the second support pin 22b and the substrate 9 through the contact portion between the second support pin 22b and the inner region B2 of the substrate 9 can be reduced. Therefore, the temperature uniformity of the substrate 9 can be further improved. Therefore, the drying unevenness of the coating film 90 formed in the coating region A1 of the substrate 9 can be further suppressed.

[0223] In addition, the entire second support pin 22b does not need to be formed of a porous resin. For example, it is sufficient that at least the second abutting portion 23b in the second support pin 22b is formed of a porous resin. For example, the second abutting portion 23b may be formed of a porous resin, and the second columnar portion 25b may be formed of a non-porous resin. Thus, the amount of heat transferred between the second support pin 22b and the substrate 9 can also be reduced. Of course, when the entire second support pin 22b is formed of a porous resin, the transfer of heat can be further reduced.

[0224] The first support pin 22a may also be formed of a porous resin like the second support pin 22b. Accordingly, the amount of heat that moves between the first support pin 22a and the substrate 9 through the contact portion between the first support pin 22a and the peripheral region B1 of the substrate 9 can be reduced. Therefore, the deviation of the temperature distribution of the peripheral region B1 of the substrate 9 can be reduced. Furthermore, the temperature difference between the peripheral region B1 and the inner region B2 of the substrate 9 can be reduced, and the movement of heat between the peripheral region B1 and the inner region B2 can be reduced. Therefore, the increase of the deviation of the temperature distribution in the end portion in the inner region B2 can be suppressed or avoided.

[0225] <3. Modifications>

[0226] The present disclosure is not limited to the above-described one embodiment, and various changes and improvements can be made without departing from the gist of the present disclosure.

[0227] In the embodiment, as long as at least one of the two or more support pins 22 supporting the peripheral area B1 of the substrate 9 is the first support pin 22a. In other words, some of the two or more support pins 22 supporting the peripheral area B1 of the substrate 9 may be the second support pins 22b. In short, the two or more support pins 22 supporting the peripheral area B1 of the substrate 9 may also include both the first support pin 22a and the second support pin 22b. If one or more thick first support pins 22a support the peripheral area B1 of the substrate 9, the displacement of the substrate 9 in the horizontal direction can be suppressed. In addition, it is ideal that at least half of the support pins 22 supporting the peripheral area B1 are the first support pins 22a.

[0228] In addition, it is sufficient as long as at least one of the two or more support pins 22 supporting the coating area A1 of the substrate 9 is the second support pin 22b. In other words, some of the two or more support pins 22 supporting the coating area A1 of the substrate 9 may also be the first support pins 22a. If one or more thin second support pins 22b support the coating area A1 of the substrate 9, the deviation of the temperature distribution of the coating area A1 can be reduced compared to the structure in which only the first support pins 22a support the coating area A1. In addition, it is ideal that at least half of the support pins 22 supporting the peripheral area B1 are the second support pins 22b.

[0229] Alternatively, the coating film 90 may be formed on the entire surface of the substrate 9 except for the peripheral region B1 .

[0230] In the above embodiment, the lifting unit 100 for lifting the support unit 20 may not be provided. In this case, the plurality of support pins 22 may be fixed to a portion in the chamber 10 such as the upper surface of the bottom straightening plate 40 or the upper surface of the bottom plate 11 .

[0231] In the above-mentioned embodiment, for example, the chamber 10 has four exhaust ports 16a, 16b, 16c, and 16d, but the present invention is not limited thereto. For example, the number of exhaust ports in the chamber 10 may be any one from one to three and five or more. In addition, for example, there may be no separate valve Va, separate valve Vb, separate valve Vc, and separate valve Vd.

[0232] In the above-described embodiment, the reduced pressure drying device 1 dries the coating film 90 on the substrate 9 by reducing pressure, but the present invention is not limited thereto. For example, the reduced pressure drying device 1 may dry the coating film 90 on the substrate 9 by reducing pressure and heating.

[0233] In one embodiment, a loading and unloading port 14 for the substrate 9 is provided on the side wall portion 12 of the chamber 10, but the invention is not limited thereto. For example, a structure in which the four side wall portions 12 and the top plate portion 13 of the chamber 10 form an integral cover portion, and the cover portion can be separated from the bottom plate portion 11 and retreat upward. In this case, for example, the cover portion can also be moved up and down by an opening and closing drive portion 16 or the like. Moreover, the chamber 10 can be selectively set to a state in which the cover portion contacts the bottom plate portion 11 via a sealing material such as an O-ring and the internal space 10s is sealed (a closed state), and a state in which the cover portion is separated from the bottom plate portion 11 upward and the internal space 10s is opened (an open state). Here, if the chamber 10 is in an open state, the substrate 9 can be loaded into the internal space 10s of the chamber 10 and the substrate 9 can be unloaded from the internal space 10s of the chamber 10. When the chamber 10 is in a closed state, the coating film 90 on the substrate 9 can be dried by reducing the pressure through exhaust from the internal space 10 s and supply of gas to the internal space 10 s.

[0234] In the embodiment, for example, the support portion 20 may have various embodiments. For example, the plurality of support plates 21 may also be one integrated support plate 21 .

[0235] In the above-described embodiment, for example, the bottom straightening plate 40 and the side straightening plate 50 may be omitted.

[0236] In the above-described embodiment, for example, various operations in the reduced-pressure drying apparatus 1 may be started or ended in response to, for example, an operation of the user on the input unit 804 or a signal input from an external device to the communication unit 806 .

[0237] In the above-described embodiment, for example, at least a part of the functional configuration implemented in the control unit 80 may include hardware such as a dedicated electronic circuit.

[0238] Furthermore, it is of course possible to appropriately combine all or part of the components constituting the above-described one embodiment and various modifications within a range that does not conflict with each other.

Claims

1. A reduced pressure drying device for drying a coating film formed on an upper surface of a substrate, the reduced pressure drying device comprising: a chamber for accommodating the substrate; a plurality of support pins for supporting the substrate from below in the chamber; as well as an exhaust part for exhausting the gas in the chamber, The plurality of support pins include at least one first support pin and at least one second support pin thinner than the first support pin. At least one of the first support pins supports the peripheral region of the substrate from below, At least one of the second support pins supports from below a region of the substrate where the coating film is formed in an inner region that is further inward than the peripheral region. The first support pin comprises a first columnar portion of equal width, The second support pin comprises a second columnar portion of equal width, The difference between the width of the first columnar portion and the width of the second columnar portion is greater than 0.5 mm. The proportion of the second columnar portion in the vertical direction of the second support pin is the largest compared to the proportion of other portions of the second support pin.

2. A reduced pressure drying device for drying a coating film formed on an upper surface of a substrate, the reduced pressure drying device comprising: a chamber for accommodating the substrate; a plurality of support pins for supporting the substrate from below in the chamber; as well as an exhaust part for exhausting the gas in the chamber, The plurality of support pins include at least one first support pin and at least one second support pin thinner than the first support pin. The plurality of first support pins support the peripheral region of the substrate from below, The plurality of second support pins support from below a region of the substrate on which the coating film is formed, in an inner region that is further inward than the peripheral region. A pitch between the plurality of first support pins is wider than a pitch between the plurality of second support pins.

3. A reduced pressure drying device for drying a coating film formed on an upper surface of a substrate, the reduced pressure drying device comprising: a chamber for accommodating the substrate; a plurality of support pins for supporting the substrate from below in the chamber; as well as an exhaust part for exhausting the gas in the chamber, The plurality of support pins include at least one first support pin and at least one second support pin thinner than the first support pin. At least one of the first support pins supports the peripheral region of the substrate from below, At least one of the second support pins supports from below a region of the substrate where the coating film is formed in an inner region that is further inward than the peripheral region. The thermal conductivity of the second support pin is 0.12 W / m·K or less.

4. The reduced pressure drying device according to any one of claims 1 to 3, wherein: The inner region of the substrate is supported only by the second supporting pins.

5. The reduced pressure drying device according to any one of claims 1 to 3, wherein: At least another one of the first support pins supports a region other than the region where the coating film is formed in the inner region of the substrate.

6. The reduced pressure drying device according to any one of claims 1 to 3, wherein: A contact area between a single first supporting pin and the substrate is larger than a contact area between a single second supporting pin and the substrate.

7. The reduced pressure drying device according to any one of claims 1 to 3, wherein: The second support pin is formed of a porous resin.

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