Reduced pressure drying apparatus

Abstract

The present invention provides a reduced-pressure drying device that can make the reduced-pressure drying time gap uniform in the substrate surface and suppress the occurrence of drying unevenness of a coating film. The reduced-pressure drying device includes: a top plate portion having a facing surface that faces the upper surface of a substrate supported by a substrate support portion; a top plate lifting portion that lifts the top plate portion in the processing space between a lower position at which the facing surface approaches the upper surface of the substrate supported by the substrate support portion and an upper position that is higher than the lower position; and a plurality of pressing pins installed to the facing surface and abutting against the peripheral edge region of one of the main surfaces to correct the warping of the substrate when the top plate portion is at the lower position. The distance (reduced-pressure drying time gap) between the upper surface of the corrected substrate and the facing surface can be made uniform in the substrate surface.

Description

Technical Field

[0001] This invention relates to a vacuum drying apparatus for drying a coating film formed on a substrate. Background Technology

[0002] As one of the manufacturing processes for semiconductor devices, there is a process in which a coating film is formed by applying a coating liquid to the surface of a substrate, and then drying it to form functional films such as resist films or protective films on the substrate surface. Furthermore, in recent years, the demand for miniaturization and thinning of semiconductor devices has become extremely high. To meet this demand, fan-out panel level packaging (FOPLP) technology, which uses substrates to manufacture semiconductor packages, has attracted considerable attention. When manufacturing semiconductor packages using FOPLP technology, the coating film applied to the surface of the substrate is dried before the exposure and development process is performed on the substrate. As an example of a substrate processing apparatus, as described in Patent Document 1, a depressurization drying apparatus is used to depressurize the space surrounding the substrate with the coating film formed, causing the solvent components to evaporate. In this apparatus, the substrate is placed on the upper surface of a substrate placement platform, and a rectifier plate is positioned above the substrate. By controlling the distance (hereinafter referred to as the "reduced pressure drying time interval") from the lower surface of the rectifier plate (corresponding to the "opposing surface of the top plate portion" of the present invention) to the upper surface of the substrate (substrate surface), the evaporation rate of the solvent component from the coating film formed on the substrate is uniformly adjusted within the substrate surface.

[0003] [Existing technical documents]

[0004] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2022-38284 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] Here, due to factors such as the material of the semiconductor packaging substrate, there is a tendency for warping to increase. Therefore, when placing the substrate on the substrate mounting platform, sometimes the periphery of the substrate is positioned higher than the center. Furthermore, this warping is also considered a problem with other types of substrates. Because of this warping, the gap during depressurization drying within the substrate surface becomes uneven. As a result, uneven drying of the coating film occurs.

[0008] The present invention was made in view of the aforementioned problem, and its object is to provide a vacuum drying apparatus that can uniformly distribute the vacuum drying interval within the substrate surface and suppress uneven drying of the coated film.

[0009] [Technical means to solve the problem]

[0010] The first aspect of the present invention is a depressurization drying apparatus, comprising: a chamber having a processing space capable of accommodating a substrate, the substrate having a coating film formed in a central region of one of its main surfaces; a substrate support portion supporting the substrate within the processing space in an upward orientation of the coating film; an exhaust portion for venting the processing space; a top plate portion having an opposing surface facing the upper surface of the substrate supported by the substrate support portion; a top plate lifting portion for lifting the top plate portion between a lower position and an upper position above the lower position within the processing space, the lower position being a position where the opposing surface is close to the upper surface of the substrate supported by the substrate support portion; and a plurality of pressing pins mounted on the opposing surface, abutting against a peripheral region of one of the main surfaces when the top plate portion is in the lower position.

[0011] In a first embodiment of the present invention, the top plate portion includes: an upper top plate connected to a top plate lifting portion; a lower top plate having facing surfaces and disposed below the upper top plate; and a plurality of connecting members at different positions within the surface of the lower top plate to connect the upper top plate and the lower top plate, wherein at least a portion of the plurality of connecting members is capable of adjusting the interval between the upper top plate and the lower top plate.

[0012] Furthermore, a second aspect of the present invention is a depressurization drying apparatus, characterized in that it comprises: a chamber having a processing space capable of accommodating a substrate, the substrate having a coating film formed in the central region of one of its main surfaces; a substrate support portion supporting the substrate within the processing space in an upward orientation of the coating film; an exhaust portion for venting the processing space; a top plate portion having an opposing surface facing the upper surface of the substrate supported by the substrate support portion; a top plate lifting portion for lifting the top plate portion between a lower position and an upper position above the lower position within the processing space, the lower position being a position where the opposing surface is close to the upper surface of the substrate supported by the substrate support portion; and a plurality of pressing pins mounted on the opposing surface, abutting against the peripheral region of one of the main surfaces when the top plate portion is in the lower position.

[0013] In a second embodiment of the invention, the depressurization drying apparatus further includes a plurality of alignment pins, which are installed at different positions around the opposing surfaces. During the period when the top plate moves to the lower position, the alignment pins slide into contact with the end of the substrate supported by the substrate support portion so as to adjust the position of the substrate in the horizontal plane.

[0014] In this invention, the top plate has a facing surface that faces the upper surface of the substrate supported by the substrate support. Therefore, by controlling the distance from the facing surface to the upper surface of the substrate, i.e., the vacuum drying time interval, the evaporation rate of the solvent from the coating film formed on the substrate can be controlled. Here, when the peripheral portion of the substrate warps upwards, the vacuum drying time interval within the substrate surface becomes uneven. Therefore, in this invention, when the top plate, which has multiple pressing pins at its peripheral portion relative to the facing surface, descends to a lower position, the pressing pins abut against the peripheral region of one of the main surfaces of the substrate to correct the warping of the substrate.

[0015] [The effects of the invention]

[0016] As described above, in this invention, the top plate portion having an opposing surface facing the upper surface of the substrate supported by the substrate support portion is configured such that a plurality of pressing pins provided on the periphery of the opposing surface are used to correct the warping of the substrate. Therefore, the distance (drying interval) between the upper surface of the corrected substrate and the opposing surface can be made uniform within the substrate surface. Attached Figure Description

[0017] Figure 1 This is a diagram illustrating a first embodiment of the vacuum drying apparatus of the present invention.

[0018] Figure 2 It means Figure 1 A perspective view showing the configuration relationship between the chamber and the substrate support in the vacuum drying apparatus.

[0019] Figure 3A This is a three-dimensional view of the top panel from an oblique angle.

[0020] Figure 3B This is a three-dimensional view of the top panel from a slightly lower angle.

[0021] Figure 4 It is a side sectional view showing the structure and adjustment actions of the top plate.

[0022] Figure 5 This is a flowchart illustrating the vacuum drying operation performed by the vacuum drying apparatus of the present invention.

[0023] Figure 6A It means Figure 1 The diagram shows the loading action of the substrate in the vacuum drying apparatus.

[0024] Figure 6B It means Figure 1 The diagram shows the chamber closure action in the vacuum drying device.

[0025] Figure 6C It means Figure 1The diagram shows the substrate correction and initial vacuum drying operation in the vacuum drying apparatus.

[0026] Figure 6D It means Figure 1 The diagram shows the main vacuum drying operation in the vacuum drying apparatus.

[0027] Figure 7A This is a perspective view of the top plate portion viewed from an obliquely upward perspective in the second embodiment of the pressure-reducing drying apparatus of the present invention.

[0028] Figure 7B This is a plan view of the top plate portion viewed from a slightly downward angle in the second embodiment of the vacuum drying apparatus of the present invention.

[0029] Figure 8 This is a diagram illustrating a portion of a third embodiment of the vacuum drying apparatus of the present invention.

[0030] [Explanation of Symbols]

[0031] 1: Reduced pressure drying device

[0032] 10: Chamber

[0033] 11: Cover

[0034] 12: Base plate

[0035] 12a: Through hole for exhaust

[0036] 12b: Through hole for cleaning

[0037] 13: Sealing components

[0038] 20: Substrate support portion

[0039] 21: Base support components

[0040] 22: Base components

[0041] 23: Support pin

[0042] 30: Exhaust section

[0043] 31: Exhaust piping

[0044] 32: Piping for cleaning

[0045] 33: Exhaust valve

[0046] 34: Pump

[0047] 35: Cleaning valve

[0048] 40: Top plate section

[0049] 41: Lower top plate

[0050] 41a: (The opposite surface of the lower top plate)

[0051] 42: Top plate

[0052] 43: Connecting structural components

[0053] 43a: Fixed connecting structural member

[0054] 43b: Push-pull bolt

[0055] 45: Alignment pin

[0056] 50: Top panel lifting unit

[0057] 51: Lifting shaft

[0058] 52: Lifting mechanism

[0059] 60: Press pin group

[0060] 61: Press pin

[0061] 90: Control Department

[0062] 91: CPU

[0063] 92: Heater drive unit

[0064] 93: Chamber drive unit

[0065] 94: Environmental Control Department

[0066] 95: Top Plate Position Control Unit

[0067] F: Coated film

[0068] GP: Vacuum drying interval

[0069] H: Heater

[0070] HD:hand

[0071] Pdw: Below

[0072] Pup: Above position

[0073] S: Substrate

[0074] S11, S12, S13, S14, S15, S16, S17, S18, S19, S20, S21, S22, S23: Steps

[0075] Sa: (the upper surface of the substrate)

[0076] Sa1: Peripheral area of ​​the upper surface

[0077] Sa2: Central region of the upper surface

[0078] SP: Processing Space Detailed Implementation

[0079] Figure 1 This is a diagram illustrating a first embodiment of the vacuum drying apparatus of the present invention. More specifically, Figure 1 This diagram combines a cross-sectional view showing the structure of the main parts of the vacuum drying apparatus 1, which is the first embodiment of the present invention, with a block diagram of the control system therefor. Furthermore, in the following figures, to clarify the arrangement of the various parts of the apparatus, as shown... Figure 1 As shown, a right-handed XYZ orthogonal coordinate system is defined. The XY plane, represented by this coordinate system, represents the horizontal direction, and the Z direction represents the vertical direction. In particular, the (-Z) direction represents the vertically downward direction.

[0080] The reduced-pressure drying apparatus 1 can be applied, for example, as part of the manufacturing process of panel-level package (PLP), to a rectangular substrate S on which a coating film F based on a processing liquid is formed on its surface. Specifically, the reduced-pressure drying apparatus 1 performs the following process: receiving the substrate S in a undried state with the coating film F, heating the substrate S and reducing the pressure of the surrounding space, thereby causing the solvent components in the coating film to evaporate and the coating film to dry and harden. Hereinafter, this substrate treatment will be referred to as "heated reduced-pressure drying treatment".

[0081] As the substrate S, a semiconductor packaging glass substrate, for example, which has a rectangular shape when viewed from above and on which semiconductor chips or wiring are stacked, can be used. As the coating film F, a photoresist film, for example, exists. Furthermore, the material of the substrate or the type of coating film is not limited to these; for example, substrates used in the manufacture of semiconductor devices or display devices other than semiconductor packaging can also be used.

[0082] The vacuum drying apparatus 1 comprises a chamber 10, a substrate support 20, an exhaust 30, a top plate 40, a top plate lifting 50, a pressing pin group 60, and a control unit 90 as its main structures. The chamber 10 receives a substrate S with a coating film F formed on its upper surface Sa and performs a prescribed treatment thereon. The exhaust 30 and the processing space of the chamber 10 (described later) Figures 6B to 6D The symbol SP in the diagram is connected, and the processing space is vented. The control unit 90 includes a central processing unit (CPU) 91, which executes a predetermined control program to control the operation of each part of the device, thereby realizing the various processes described below. In addition, Figure 1 The dashed arrows in the diagram indicate the flow of control signals from the control unit 90 to various parts of the device.

[0083] Figure 2 It means Figure 1 The diagram shows a perspective view of the arrangement of the chamber and the substrate support in the vacuum drying apparatus. The chamber 10 functions to form a processing space for depressurizing the area around the substrate S. Figures 6B to 6D The chamber 10 is a box-shaped structure consisting of a cover 11 and a base plate 12, which are combined by a sealing member 13 to prevent solvent components volatilized during processing from spreading to the surrounding area. Furthermore, by covering the area around the heated substrate S, heat dissipation is suppressed and energy efficiency is improved. More specifically, the cover 11, with a cavity having an opening at the bottom, closes the upper part of the generally flat base plate 12, thereby forming a processing space between the cover 11 and the base plate 12. The cover 11 and the base plate 12 are made of a metallic material such as stainless steel or aluminum. The sealing member 13 is made of an elastic material such as rubber.

[0084] The cover 11 is supported by a support mechanism (not shown) so that it can move up and down in the vertical direction (Z direction). A chamber drive unit 93 provided in the control unit 90 causes the cover 11 to move up and down in the Z direction. This opens / closes the chamber 10. Specifically, the chamber drive unit 93, when the cover 11 is positioned... Figure 1 In the lower state shown, chamber 10 is closed, forming a processing space inside. On the other hand, the cover 11 moves upward using the chamber drive 93, as... Figure 1 and Figure 2 As shown, the cover 11 is separated from the base plate 12, opening up the processing space. In the closed state of the cover 11 ( Figures 6B to 6D Processing of substrate S is performed under the condition of ) and on the other hand, in the open state ( Figure 1 , Figure 2 , Figure 6A Under these conditions, it is possible to remove / place the substrate S or perform maintenance on internal components.

[0085] Furthermore, a planar heater H is mounted on the outer surface of the cover 11. Each heater H is electrically connected to the heater drive unit 92 of the control unit 90. Therefore, by operating the heater H using the heater drive unit 92, the substrate S can be heated when the cover 11 is closed. In this embodiment, a so-called panel heater is used as the heater H, but a strip heater or a wire heater can also be used. In addition, the mounting position of the heater H is not limited to the outer surface of the cover 11; it can also be mounted on the inner surface or built into the cover 11.

[0086] like Figure 1 and Figure 2As shown, a substrate support portion 20 is provided on the upper surface of the base plate portion 12. Multiple (four in this embodiment) base support members 21 are erected from the upper surface of the base plate portion 12, surrounding the venting through-hole 12a provided in the center of the base plate portion 12. These base support members 21 support the base members 22. Furthermore, the base members 22 have a planar dimension wider than the substrate S, and multiple support pins 23 are erected from their upper surface. In this embodiment, as... Figure 2 As shown, when viewed from above, the 16 support pins 23 are arranged in a 4×4 matrix, which enables the coated film F to be horizontally supported on the substrate S from below with the coating film F facing upwards.

[0087] The exhaust pipe 31 of the exhaust section 30 is connected to the exhaust through hole 12a. In addition, the base plate 12, besides the exhaust through hole 12a, also has a cleaning through hole 12b. Furthermore, the cleaning pipe 32 of the exhaust section 30 is connected to the cleaning through hole 12b. The exhaust pipe 31 is connected to an exhaust line (not shown) via an exhaust valve 33 and a pump 34. The cleaning pipe 32 is connected to a cleaning gas source (not shown) via a cleaning valve 35.

[0088] The exhaust unit 30 is controlled by the environmental control unit 94 of the control unit 90. Specifically, the exhaust valve 33 and pump 34 operate according to the control signal from the environmental control unit 94 to exhaust the gas in the chamber 10, thereby reducing the pressure in the processing space. Additionally, the cleaning valve 35 operates according to the control signal from the environmental control unit 94, introducing cleaning gas from an external gas source into the processing space. Thus, the environment within the processing space is controlled by the exhaust unit 30 operating according to the control signal from the environmental control unit 94. Then, under this controlled environment, a reduced-pressure drying process is performed. Furthermore, in order to adjust the evaporation rate of the solvent from the coating film F formed on the substrate S during this reduced-pressure drying process, a top plate 40 is provided in this embodiment.

[0089] Figure 3A This is a three-dimensional view of the top plate and base plate from an oblique angle. Figure 3B This is a three-dimensional view of the top panel from a slightly downward angle. For example... Figure 1 and Figure 3AAs shown, the top plate portion 40 is configured to cover the substrate S, on which a coating film F is formed, in the central region Sa2 of the upper surface, excluding the peripheral region Sa1 of the upper surface. The top plate portion 40 has: a lower top plate 41, the lower surface of which functions as an opposing surface 41a that is substantially parallel to the upper surface Sa of the substrate S; and an upper top plate 42, which is disposed directly above the lower top plate 41. The opposing surface 41a of the lower top plate 41 is larger than the planar dimension of the substrate S, and when it is positioned directly above the substrate S by the top plate lifting portion 50, it covers the entire substrate when viewed from above.

[0090] An upper top plate 42 is disposed directly above the lower top plate 41. For example... Figure 3A As shown, the upper top plate 42 has the same planar dimensions as the lower top plate 41. To achieve weight reduction in the upper top plate 42, a punched portion is provided in the upper top plate 42, excluding the central and peripheral areas. A lifting shaft 51 of the top plate lifting section 50 is connected to the central portion of the upper surface of the upper top plate 42. Furthermore, the upper top plate 42 and the lower top plate 41 are interconnected and integrated by four connecting members 43 while being separated by a small distance in the vertical direction Z. Moreover, the lifting shaft 51 is mounted to the cover 11 in a vertically Z-direction movably, and a lifting mechanism 52 for raising and lowering the lifting shaft 51 is fixedly mounted to the cover 11. Therefore, when the cover 11 is raised or lowered by the chamber drive 93 of the control unit 90, the top plate lifting section 50 and the top plate 40 are raised and lowered integrally. For example, when the cover 11 moves upward, as... Figure 1 As shown, the top plate portion 40 is positioned upwards away from the substrate support portion 20 and the substrate S supported by the substrate support portion 20. Conversely, by moving downwards through the cover portion 11, the top plate portion 40 approaches the substrate S.

[0091] In addition, in this embodiment, to achieve the function of correcting the warping of the substrate S and to adjust the distance between the substrate S and the lower top plate 41 in the vertical direction Z with high precision, a pressing pin group 60 and a top plate lifting part 50 are provided. The pressing pin group 60 is composed of a plurality of pressing pins 61, which protrude downward from the facing surface 41a of the lower top plate 41. In this embodiment, in order to press the peripheral portion of the upper surface of the substrate S, 10 pressing pins 61 are detachably mounted on the lower surface (facing surface 41a) of the lower top plate 41 with the upper surface peripheral portion of the substrate S facing it. Therefore, a total of 40 pressing pins 61 are provided facing the peripheral portion of the upper surface of the substrate S.

[0092] In the top plate lifting unit 50, the lifting mechanism 52 operates according to the lifting command from the top plate position control unit 95 of the control unit 90, causing the lifting shaft 51 to shift in the vertical direction Z.

[0093] The upper top plate 42, lower top plate 41, connecting structural member 43, and top plate lifting part 50, together with the cover part 11, move vertically in the Z direction. Therefore, even when the top plate lifting part 50 stops, for example, by the descent of the cover part 11 caused by the chamber drive part 93, the top plate part 40 approaches the substrate S and stops. Here, if the periphery of the substrate S warps significantly upward, sometimes several pressing pins 61 abut against the periphery of the substrate S, pressing the periphery of the substrate S to correct the warping (see the explanation below). Figure 6B In addition, when the warpage of the substrate S is relatively small, at the point when the descent of the cover 11 stops, sometimes all the pressing pins 61 move away from the periphery of the substrate S upwards.

[0094] After the descent of the cover 11 stops, if only the top plate 40 (= lower top plate 41 + upper top plate 42 + connecting member 43) descends according to the descent command from the top plate position control unit 95, the gap between the lower top plate 41 and the substrate S narrows, and the central region of the facing surface 41a of the lower top plate 41 approaches the position directly above the upper surface Sa of the substrate S, thus covering the coating film F from above. Moreover, all the pressing pins 61 press the peripheral portion of the upper surface of the substrate S downwards along the entire circumference, so the gap between the lower top plate 41 and the substrate S is consistent with the amount of protrusion of the pressing pins 61 from below the facing surface 41a, which can correct the warping of the substrate S within the substrate surface.

[0095] Furthermore, in this embodiment, to prevent interference between the connecting structural member 43 and the substrate S during the lifting and lowering movement of the top plate portion 40, such as... Figure 3A and Figure 3B As shown, four connecting structural members 43 are mounted near the peripheral corners of the lower top plate 41 and the upper top plate 42. More specifically, the overlapping area of ​​the overlapping substrates S (in the view from above) is... Figure 3B In the area further outward from the region enclosed by a single-dotted line, four connecting members 43 are provided. One of these is a fixed connecting member 43a that connects the lower top plate 41 and the upper top plate 42 with a collar (not shown) between them. The other three consist of push-pull bolts 43b used to adjust the spacing between the lower top plate 41 and the upper top plate 42. Therefore, the horizontal position of the lower top plate 41 can be easily and accurately adjusted by the operator. (Refer to...) Figure 4 The adjustment action will be explained.

[0096] Figure 4 This is a schematic diagram illustrating the process of adjusting the posture of the top plate below. For example... Figure 4As shown in column (a), in the top plate portion 40, if the lower top plate 41 is tilted relative to the upper top plate 42, the gap during the drying process, i.e., the gap during depressurized drying, will be different within the surface of the substrate S, making it difficult to perform uniform depressurized drying. This tilting of the lower top plate 41 occurs during the initial assembly stage of the device or due to changes over the years. Therefore, in this embodiment, a leveling process is performed when the depressurized drying device 1 is not in operation, such as during the assembly stage, the factory setup stage, and the maintenance stage. More specifically, the operator operates the three push-pull bolts 43b, such as... Figure 4 As shown in column (b), the lower top plate 41 can be adjusted to a horizontal position. In the vacuum drying apparatus 1 with the lower top plate 41 adjusted in this way, the heating vacuum drying process is performed in the order described below.

[0097] Figure 5 It means by Figure 1 The flowchart illustrates the process of heat-pressure drying in the vacuum drying apparatus shown. Additionally, Figures 6A to 6D These are schematic diagrams illustrating the operation of various parts of the apparatus during the heating and depressurization drying process. The process is achieved by the CPU 91 of the control unit 90 executing a pre-prepared control program and causing each part of the apparatus to perform predetermined actions. The cover 11 is preheated to a predetermined temperature by the operation of the heater H (step S11).

[0098] In addition, such as Figure 6A As shown, the cover 11, top plate lifting unit 50, and top plate 40 are raised integrally by the chamber drive unit 93, forming a loading / unloading space for loading / unloading the substrate S. Then, the untreated substrate S (i.e., carrying the undried coating film F) held by the hand HD of an external transport robot is moved through the loading / unloading space to a position above the support pin 23. Afterwards, as... Figure 6A As indicated by the arrow, the substrate S is transferred to the support pin 23 by lowering the hand HD (step S12). Furthermore, the loading and unloading of the substrate S is not limited to using a transport robot, and can be carried out by any method using a suitable transport mechanism capable of transporting in a horizontal posture.

[0099] When the substrate S is loaded in the manner described above, the hand HD retracts from the loading / unloading space. Then, the cover 11, top plate lifting unit 50, and top plate 40 are lowered integrally via the chamber drive unit 93 (step S13). As a result, the cover 11 is brought into close contact with the bottom plate 12 via the sealing member 13, forming a closed processing space SP. At this time, the top plate 40 is located at an upper position Pup, moving upwards from the substrate S supported by the support pin 23. This upper position Pup, which is suitable for subsequent depressurization drying, refers to a height position that moves vertically upwards from the upper surface Sa of the substrate S, away from the depressurization drying time interval GP.

[0100] The periphery of substrate S sometimes warps upwards. When the warping is zero or small, the pressing pin 61 of the top plate 40 does not contact the periphery of the upper surface of substrate S. On the other hand, as... Figure 6B As shown, in cases of significant warpage, sometimes a portion of the pressing pin 61 contacts the peripheral portion of the upper surface of the substrate S, pressing the peripheral portion of the upper surface downwards. However, even in this case, the pressing pin 61 mostly moves upwards away from the substrate S.

[0101] Next, only the top plate 40 (= lower top plate 41 + upper top plate 42 + connecting structural member 43) descends to a lower position Pdw, which is lower than the upper position Pup, according to the descent command from the top plate position control unit 95. At this time, as Figure 6C As shown, all pressing pins 61 abut against and press against the peripheral area Sa1 of the upper surface of the substrate S, thereby correcting the warping of the substrate S (step S14). In parallel with this, the decompression of the processing space SP by the environmental control unit 94 begins (step S15).

[0102] In this embodiment, during the initial stage of correction and reduced-pressure drying of the substrate S (hereinafter referred to as the "initial drying period"), in order to prevent a decrease in the drying quality of the coating film F due to the rapid evaporation of solvent components in the coating film F, the environmental control unit 94 adjusts the exhaust volume. That is, during the initial drying period, the drying speed of the coating film F is suppressed, and the exhaust volume (exhaust volume per unit time) is also suppressed until the amount of solvent components in the coating film F is lower than a predetermined value, reaching a state known as semi-dry or not completely dried. In this specification, the exhaust volume under the state of suppressing the exhaust volume based on the exhaust unit 30 as described above is called "slow exhaust," and the exhaust volume in slow exhaust is equivalent to an example of the "first exhaust volume" of the present invention. On the other hand, as will be explained later, the case where exhaust is performed at an exhaust volume higher than slow exhaust in order to increase the reduced-pressure drying speed is called "main exhaust," and the exhaust volume in main exhaust is equivalent to an example of the "second exhaust volume" of the present invention.

[0103] During the initial drying period (YES in step S16), as Figure 6D As shown, the top plate portion 40 (= lower top plate 41 + upper top plate 42 + connecting structural member 43) is raised to the upper position Pup only by the top plate position control unit 95 (step S17). This process is equivalent to an example of the "top plate lifting process" of the present invention. As a result, the depressurization drying time interval GP becomes a preset value. In addition, through the correction process, the interval between the upper surface Sa and the opposing surface 41a of the lower top plate 41, i.e., the depressurization drying time interval GP, becomes uniform. Then, in this state, the environmental control unit 94 switches from slow exhaust to main exhaust, and the residual solvent components of the coating film F evaporate rapidly (step S18). As a result, the solvent evaporation rate can be adjusted with relatively high and excellent in-plane uniformity. As a result, the coating film F of the substrate S can be dried with excellent quality while shortening the depressurization drying time.

[0104] When the lower top plate 41 is positioned at the desired upper position Pup as described above, and depressurization drying is performed via the main exhaust until the solvent concentration in the coated film F reaches below a specified value (hereinafter referred to as the "main drying period") ("Yes" in step S19), the exhaust section 30 stops exhausting. Then, by introducing cleaning gas (step S20), the depressurization state of the processing space SP is released. Next, the cover 11 is moved upwards to a position where the substrate S can be moved in / out (…). Figure 6A (as shown in step S21), the substrate S within the processing space SP is opened. Then, by receiving an external transport robot, the dried substrate S is moved outward (step S22).

[0105] If there is a next substrate S to be processed ("Yes" in step S23), the process returns to step S12 to receive a new substrate S and performs the same processing as described above. On the other hand, if there is no new substrate S ("No" in step S23), the processing can be terminated by a predetermined termination action.

[0106] As described above, according to the first embodiment, a plurality of pressing pins 61 are provided at the periphery of the facing surface 41a of the lower top plate 41. Furthermore, before performing decompression drying with the facing surface 41a facing the upper surface Sa of the substrate S, the warpage of the substrate S is corrected by positioning the top plate portion 40 at the lower position Pdw using the plurality of pressing pins 61. Therefore, the distance between the corrected upper surface Sa of the substrate S and the facing surface 41a, i.e., the decompression drying time interval GP, can be uniformly distributed within the substrate surface. As a result, even for substrates containing warpage, drying processes accompanied by decompression and heating can be performed effectively.

[0107] Furthermore, in this embodiment, as four connecting members 43, one fixed connecting member 43a and three push-pull bolts 43b are disposed at different positions within the surface of the lower top plate 41. Therefore, even as Figure 4 As shown in column (a), the lower top plate 41 is tilted relative to the horizontal plane, and can be adjusted by means of three push-pull bolts 43b. Figure 4 As shown in column (b), the lower top plate 41 is adjusted to a horizontal position. Therefore, the warpage correction can be performed well, and the decompression drying time gap GP can be uniformly distributed within the substrate surface.

[0108] Furthermore, in this embodiment, three push-pull bolts 43b are used as connecting members for adjusting the spacing between the upper top plate 42 and the lower top plate 41, but it is also possible to use connecting members other than the push-pull bolts 43b for adjustment. In addition, the number of connecting members is not limited to "3".

[0109] Furthermore, when viewed from above, the connecting member 43 is located further outward than the substrate S supported by the substrate support 20. Therefore, interference between the connecting member 43 and the substrate S can be effectively prevented during the lifting and lowering movement of the top plate 40.

[0110] Furthermore, each pressing pin 61 can be freely attached to and detached from the lower top plate 41. Therefore, various pressing pins 61 with different protrusions from the lower top plate 41 can be prepared in advance, and the type of pressing pin 61 installed on the lower top plate 41 can be changed according to the thickness of the substrate S. As a result, it can accommodate different types of substrate S or various formulations, thereby improving the versatility of the vacuum drying apparatus 1. Alternatively, the lower position Pdw of the top plate section 40 can be appropriately changed by the top plate position control unit 95 instead of changing the type of pressing pin 61.

[0111] Furthermore, in this embodiment, the vacuum drying process is performed in two stages: an initial vacuum drying process (steps S14 and S15) and a main vacuum drying process (steps S18 and S19). Therefore, it is possible to effectively prevent adverse conditions such as damage to the uniformity of the coating film F due to the rapid evaporation of solvent from the coating film F during the correction process, and to achieve excellent quality in vacuum drying of the coating film F.

[0112] As described above, in the first embodiment, the upper surface Sa of the substrate S corresponds to "one of the main surfaces" of the present invention, and the peripheral region Sa1 and the central region Sa2 of the upper surface correspond to the "peripheral region" and "central region" of the present invention, respectively. Furthermore, the initial drying period and the main drying period correspond to an example of the "first predetermined time" and "second predetermined time" of the present invention, respectively.

[0113] Figure 7Aand Figure 7B These are perspective and plan views of the second embodiment of the vacuum drying apparatus of the present invention, viewed from below. The second embodiment differs significantly from the first embodiment in that it adds two sets of alignment pin pairs, each containing two alignment pins 45; the other structures are the same as the first embodiment. One set of alignment pin pairs is located in the overlapping area of ​​the overlapping substrates S when viewed from below (in...). Figure 7B One corner portion of the area (enclosed by a single-dot dashed line) is provided, and another set of alignment pins is provided at the corner portion diagonally opposite to the corner portion. Furthermore, when comparing the downward protrusion of each alignment pin 45 with that of the pressing pin 61 from the opposing surface 41a, the protrusion of each alignment pin 45 is greater than that of the pressing pin 61, and the front end of the alignment pin 45 is machined into a shape that gradually tapers downwards. Therefore, when the top plate portion 40 is lowered in step S14, the alignment pin 45 also lowers along with the top plate portion 40. Moreover, before the pressing pin 61 abuts against the substrate S, the front end of the alignment pin 45 abuts against the corner portion of the substrate S, and the substrate S is positioned in the substrate posture defined by the two sets of alignment pins. Afterwards, the substrate S is pressed by the multiple pressing pins 61, and warping is corrected. Therefore, the substrate S can always be subjected to depressurization drying in a predetermined position and in a warping-corrected state, thereby enabling more stable and high-quality depressurization drying. In the second embodiment, two sets of alignment pin pairs are used, but three or more sets of alignment pin pairs may also be used. In addition, alignment pins 45 are provided corresponding to the corner portions of the substrate S, but alignment pins that engage with other portions to position the substrate S may also be used.

[0114] Furthermore, the present invention is not limited to the described embodiments, and various modifications can be made beyond the described embodiments as long as they do not depart from its spirit. For example, in the described embodiment, the top plate portion 40 is formed by the lower top plate 41 and the upper top plate 42, but as... Figure 8 As shown, the top plate portion 40 may also be formed solely by the lower top plate 41 (third embodiment). That is, the lower surface of the lower top plate 41 may function as the "opposing surface" of the present invention, and the upper surface of the lower top plate 41 may be connected to the lifting shaft 51.

[0115] In addition, in the above embodiment, the lower surface of the substrate S is supported by 16 support pins 23 and the upper surface periphery Sa1 of the substrate S is pressed by 40 pressing pins 61. However, the number or arrangement of the support pins 23 and pressing pins 61 can be adapted to suit the application.

[0116] Furthermore, in the above embodiment, the opening and closing of the processing space SP is switched by raising and lowering the cover 11, but it can also be configured to switch by raising and lowering the base plate 12 or both.

[0117] [Industry availability]

[0118] This invention relates to a vacuum drying apparatus for drying a coating film formed on a substrate.

Claims

1. A vacuum drying apparatus, characterized in that, include: A chamber having a processing space capable of accommodating a substrate, wherein a coating film is formed in the central region of one of its main surfaces; The substrate support portion supports the substrate within the processing space in an orientation in which the coated film faces upward. An exhaust section is used to exhaust air from the processing space. The top plate portion has a facing surface that faces the upper surface of the substrate supported by the substrate support portion; The top plate lifting unit moves the top plate between a lower position and an upper position that is higher than the lower position within the processing space. The lower position is the position where the opposing surface is close to the upper surface of the substrate supported by the substrate support unit. as well as Multiple pressing pins are installed on the opposing surfaces and, when the top plate is in the lower position, abut against the peripheral area of ​​one of the main surfaces. The top plate portion has: The upper top plate is connected to the top plate lifting part; The lower top plate has the opposing surface and is disposed below the upper top plate; as well as Multiple connecting structural members, located at different positions within the surface of the lower top plate, connect the upper top plate and the lower top plate. At least a portion of the plurality of connecting structural members are capable of adjusting the spacing between the upper top plate and the lower top plate. The reduced pressure drying device also includes multiple alignment pins and a chamber drive unit. The plurality of alignment pins are suspended from the opposing surfaces toward the end face of the substrate supported by the substrate support portion. The chamber has a base plate and a cover. The cover is lowered by the chamber drive unit, thereby closing the upper part of the base plate and forming the processing space. Regarding the amount of protrusion downwards from the opposing surfaces, the alignment pin is longer than the pressing pin. When the cover and the top plate descend as a whole due to the chamber drive, the front end of the alignment pin engages with the end face of the substrate before the pressing pin abuts against the peripheral area of ​​one of the main surfaces, thereby adjusting the position of the substrate in the horizontal plane.

2. The vacuum drying apparatus according to claim 1, wherein, When viewed from above, the plurality of connecting structural members are located further outward than the substrate supported by the substrate support.

3. The vacuum drying apparatus according to claim 1 or 2, wherein, The plurality of pressing pins are detachable from the lower top plate.

4. The vacuum drying apparatus according to claim 1 or 2 further includes a control unit. The control unit controls the lifting and lowering unit of the top plate. The plurality of pressing pins are detachable from the lower top plate. The control unit adjusts the amount by which the top plate descends from the upper position based on the amount by which the plurality of pressing pins installed on the lower top plate protrude downward from the opposing surfaces.

5. The vacuum drying apparatus according to claim 1 or 2 further includes a control unit. The control unit controls the top plate lifting unit and the exhaust unit. The control unit performs the following processing: The initial depressurization drying process involves controlling the lifting section of the top plate so that the peripheral area of ​​one of the main surfaces abuts against the plurality of pressing pins, and controlling the exhaust section in such a way that the exhaust volume from the processing space per unit time is a first exhaust volume, while the depressurization drying of the coating film continues for a first predetermined time. The top plate lifting process involves controlling the top plate lifting section after the initial decompression drying process to raise the top plate to the above position. as well as The main depressurization drying process controls the exhaust section in such a way that the exhaust volume from the processing space per unit time becomes a second exhaust volume that is greater than the first exhaust volume, while the depressurization drying of the coated film continues for a second predetermined time.

6. The vacuum drying apparatus according to claim 5, wherein, After the top plate is raised, the control unit performs the main decompression drying process.

7. A vacuum drying apparatus, characterized in that, include: A chamber having a processing space capable of accommodating a substrate, wherein a coating film is formed in the central region of one of its main surfaces; The substrate support portion supports the substrate within the processing space in an orientation in which the coated film faces upward. An exhaust section is used to exhaust air from the processing space. The top plate portion has a facing surface that faces the upper surface of the substrate supported by the substrate support portion; The top plate lifting unit moves the top plate between a lower position and an upper position that is higher than the lower position within the processing space. The lower position is the position where the opposing surface is close to the upper surface of the substrate supported by the substrate support unit. as well as Multiple pressing pins are installed on the opposing surfaces and, when the top plate is in the lower position, abut against the peripheral area of ​​one of the main surfaces. The reduced pressure drying device also includes multiple alignment pins. The plurality of alignment pins are installed at different positions around the opposing surfaces, and during the movement of the top plate to the lower position, they slide into contact with the end of the substrate supported by the substrate support to adjust the position of the substrate in the horizontal plane.

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