Substrate processing apparatus and substrate processing method

Abstract

The substrate processing apparatus of the present application can perform a drying process with reduced pressure and heating on a warped substrate. To this end, a substrate processing apparatus (1) dries a coating film (F) formed on a main surface of a substrate (S) by heating the substrate (S) and reducing the pressure of the space around the substrate (S), and has: a chamber (10) having a processing space in which the substrate (S) can be housed in a horizontal posture; a support portion (32) that abuts against the lower surface of the substrate (S) and supports the substrate (S) from below in the processing space (SP); a correction member (41) that partially abuts against the upper surface of the substrate (S) supported by the support portion (32) and corrects the warp of the substrate (S); a heating portion (20) that heats the lower surface of the substrate (S) supported by the support portion (32) in the processing space (SP); and a pressure reduction portion (50) that reduces the pressure of the processing space (SP).

Description

Technical Field

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

[0002] As a manufacturing process for semiconductor devices, a coating film is formed by applying a coating liquid to the surface of a substrate and then drying it, thereby forming a functional film such as a resist film or a protective film on the substrate surface. Until now, such drying processes have typically been performed separately by specialized equipment: depressurization drying, which involves reducing the pressure in the space surrounding the substrate with the coating film to allow the solvent components to evaporate; and heat drying, which involves heating the substrate after depressurization to completely dry the coating film (see, for example, Japanese Patent Application Publication No. 2006-105524 (Patent Document 1)).

[0003] Such existing technologies have problems that need to be solved, such as the need to move the substrate between devices, which cannot shorten the processing time and the increased area occupied by the devices. In order to address these problems, the applicant of this application first disclosed a technology that can perform depressurized drying and heated drying processes with a single device (see Japanese Patent No. 5089288 (Patent Document 2)).

[0004] In this device, a substrate with a coating film is held in a horizontal position within a chamber that can depressurize the internal space. Then, the internal space is depressurized, and the substrate is further heated by a heating lamp installed in the chamber to dry the coating film.

[0005] In recent years, the substrates targeted for this type of processing have become increasingly larger. Consequently, these substrates are prone to warping and difficult to heat uniformly. For example, in semiconductor packages manufactured using methods such as wafer-level packaging (WLP) or panel-level packaging (PLP), multiple semiconductor chips and inter-chip wiring are stacked on a glass substrate. The difference in thermal shrinkage or thermal expansion rates is greater than that of semiconductor substrates with only resist layers. Therefore, substrate warping is significant. Summary of the Invention

[0006] The present invention was made in view of the above-mentioned problems, and its object is to provide a substrate processing technology that can perform drying process with decompression and heating well even for warped substrates.

[0007] One aspect of the invention is a substrate processing apparatus that dries a coating film formed on the main surface of a substrate by heating the substrate and depressurizing the space surrounding it. To achieve this objective, the substrate processing apparatus includes: a chamber having a processing space capable of receiving the substrate in a horizontal position; a support portion within the processing space that abuts against the lower surface of the substrate and supports the substrate from below; a straightening member that partially abuts against the upper surface of the substrate supported by the support portion and corrects warpage of the substrate; a heating portion within the processing space that heats the lower surface of the substrate supported by the support portion; and a depressurization portion that depressurizes the processing space.

[0008] Another aspect of the present invention is a substrate processing method that heats a substrate and depressurizes the space surrounding it to dry a coating film formed on the main surface of the substrate. To achieve the above objective, the substrate processing method includes: a chamber containing a heating portion for heating the substrate is disposed within a processing space; a support portion abuts against the lower surface of the substrate and supports the substrate above the heating portion at a predetermined gap; a correction member abuts against a portion of the upper surface of the substrate supported by the support portion to correct warping of the substrate; and depressurizes the processing space to heat the substrate via the heating portion to dry the coating film.

[0009] In structures where the substrate is heated from the lower surface, uneven heating is impossible if the substrate is warped, resulting in variations in the quality of the dried coating. In the invention described above, the corrective member abuts against the upper surface of the substrate, which is supported from the lower surface by the support portion, thereby holding the substrate from both sides and correcting any warping. Therefore, even with a warped substrate, uneven heating of the coating on the substrate surface can be suppressed, and the coating can be dried effectively.

[0010] As described above, in this invention, warping can be corrected by the correcting member abutting against the upper surface of the substrate. Therefore, drying processes involving depressurization and heating can be performed effectively on warped substrates. Attached Figure Description

[0011] Figure 1 This is a diagram illustrating one embodiment of the substrate processing apparatus of the present invention.

[0012] Figures 2A to 2C This diagram illustrates the actions of each part when the substrate is moved into the chamber.

[0013] Figure 3A and Figure 3B This is a diagram showing the configuration of the lifting pins and the straightening pins.

[0014] Figure 4This is a diagram showing an example of the configuration of the lower heater.

[0015] Figure 5 This is a flowchart illustrating the heating and decompression drying process performed by the substrate processing apparatus.

[0016] Explanation of reference numerals in the attached figures:

[0017] 1. Substrate processing apparatus

[0018] 10 chambers

[0019] 11. Cover (Upper Unit)

[0020] 12. Base plate (lower side unit)

[0021] 15. Lower heater (second heating section)

[0022] 20 Hot plate (heating section)

[0023] 32 Lifting pin (support part)

[0024] 41. Correcting pin (correcting component)

[0025] 42 Adjusting nut (adjusting mechanism)

[0026] 50 Exhaust section (pressure relief section)

[0027] F Coating film

[0028] S substrate

[0029] SP processing space Detailed Implementation

[0030] Figure 1 This is a diagram illustrating one embodiment of the substrate processing apparatus of the present invention. More specifically, Figure 1 This diagram combines a cross-sectional view showing the structure of the main parts of a substrate processing apparatus 1 according to one embodiment of the present invention with a block diagram of the corresponding control system. 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 rectangular coordinate system XYZ is defined. The XY plane in this coordinate system represents the horizontal plane, and the Z direction represents the vertical direction. In particular, the (-Z) direction represents the vertically downward direction.

[0031] This substrate processing apparatus 1 can be applied, for example, to certain manufacturing processes in panel-level packaging (PLP). Specifically, the substrate processing apparatus 1 receives a substrate S with a coating film F formed of a processing liquid formed on its surface while the coating film F is still wet, heats the substrate S, and depressurizes the surrounding space. As a result, a process is performed in the substrate processing apparatus 1 to evaporate the solvent components in the coating film and to dry and cure the coating film. Hereinafter, this substrate processing will be referred to as "heat-depressurization drying process".

[0032] The substrate S can be, for example, a rectangular glass substrate for semiconductor packaging with semiconductor chips or wiring stacked on its surface. The coating film F is, for example, a photoresist film. However, the substrate material and the type of coating film are not limited to these. Furthermore, the substrate to be processed can be, for example, a substrate used for manufacturing semiconductor devices other than semiconductor packaging.

[0033] The main structure of the substrate processing apparatus 1 includes a chamber 10, an exhaust unit 50, and a control unit 90. The chamber 10 houses a substrate S with a coating film F formed on its upper surface Sa and performs prescribed processing there. The exhaust unit 50 is connected to the internal space of the chamber 10 and exhausts air from the internal space. The control unit 90 has a CPU (Central Processing Unit) 91. The CPU 91 controls the operation of various parts of the apparatus by executing a prescribed control program, thereby implementing the various processes described below. Furthermore, Figure 1 The dashed arrows in the diagram indicate the direction of the control signal from the control unit 90 to various parts of the device.

[0034] The function of chamber 10 is to form a processing space SP for depressurizing the area around the substrate S, preventing the dispersion of volatile gas components generated during processing, and to suppress heat loss and improve energy efficiency by covering the area around the heated substrate S. For these purposes, chamber 10 is formed as a box-shaped structure combining a cover portion 11 and a base plate portion 12 via a sealing member 13. More specifically, the cover portion 11, having a cavity with an opening at the bottom, closes the upper part of the generally flat base plate portion 12, thereby forming the processing space SP between the cover portion 11 and the base plate portion 12. The cover portion 11 and the base plate portion 12 are formed, for example, from a metallic material such as stainless steel or aluminum. Furthermore, the sealing member 13 is formed from an elastic material such as rubber.

[0035] The cover 11 is supported by a support mechanism (not shown) and can move up and down in the vertical direction (Z direction). A chamber drive unit 93 provided in the control unit 90 moves the cover 11 up and down in the Z direction, thereby opening and closing the chamber 10. Specifically, the chamber 10 is positioned by the chamber drive unit 93 to hold the cover 11 in place. Figure 1The lower part is closed in the state shown, forming a processing space SP inside. On the other hand, the cover 11 is moved upward by the chamber drive 93, thereby separating the cover 11 and the bottom plate 12, and the processing space SP communicates with the external space. Processing of the substrate S can be performed when the cover 11 is closed, and the substrate S can be moved in and out, and internal component maintenance can be performed when the cover 11 is open.

[0036] A heating plate 20 is provided on the bottom plate 12 of the chamber 10. The heating plate 20 is a flat plate-shaped member whose upper surface size is approximately the same as or slightly smaller than that of the substrate S when viewed from above. As a heat source for heating the heating plate 20, a heater (not shown) is built inside the heating plate 20. To distinguish this heater from other heat sources, it will be referred to as the "internal heater" below. The heating plate 20 is supported by a support member (not shown) and is separated from the upper surface of the bottom plate 12 from above. This allows for thermal separation between the heating plate 20 and the bottom plate 12. Power is supplied to the internal heater from the internal heater control unit 94 of the control unit 90, thereby heating the heater and heating the heating plate 20. The internal heater control unit 94 controls the internal heater to reach a predetermined temperature on the upper surface 21 of the heating plate 20 according to control commands from the CPU 91. As a result, the substrate S is uniformly heated by radiant heat from the heating plate 20.

[0037] To facilitate the smooth transfer of the substrate S between the hot plate 20 and the external handling robot, a lifting mechanism 30 is provided within the substrate processing apparatus 1. Specifically, multiple through holes extending in the vertical direction Z are provided on the bottom plate 12 of the chamber 10 and the hot plate 20, and lifting pins 32 are inserted into each through hole. The lower end of each lifting pin 32 is fixed to a lifting member 33. The lifting member 33 supports the lifting pins 32 by freely lifting and lowering them in the vertical direction via the lifting pin drive 92 of the control unit 90. The lifting pin drive 92 is activated according to the lifting command from the CPU 91, causing the lifting member 33 to rise and fall. Thus, each lifting pin 32 rises and falls as a whole. The lifting pin 32 moves up and down between an upper position and a lower position, where the upper end of the lifting pin 32 protrudes significantly upwards from the upper surface 21 of the hot plate 20, and the lower position is where the upper end of the lifting pin 32 protrudes less from the upper surface 21 of the hot plate 20.

[0038] Figure 1The diagram shows the lifting pin in its lower position. In this position, the upper end of the lifting pin 32 protrudes slightly upward from the upper surface 21 of the hot plate 20. Therefore, the substrate S is supported in a horizontal position with its lower surface Sb separated from the upper surface 21 of the hot plate 20 by a small gap. Alternatively, instead of being supported by the lifting pin 32, the substrate S can also be supported by a protrusion provided on the upper surface 21 of the hot plate 20. In this case, the lifting pin 32 can be located further downward and separated from the substrate S.

[0039] The substrate S is heated by radiant heat from the upper surface 21 of the hot plate 20. By providing a gap between the lower surface Sb of the substrate S and the upper surface 21 of the hot plate 20, heat transfer from the hot plate 20 to the substrate S occurs primarily through radiation, not conduction. This suppresses uneven heating of the substrate S caused by temperature variations on the hot plate 20. As a result, the coating film F formed on the substrate S is heated uniformly, resulting in a homogeneous film.

[0040] The substrate S that is transported in as the object of processing is not limited to maintaining a planar state; it may also be flexed or warped. For example, a substrate S with functional layers of different thermal expansion coefficients may be transported in directly in a warped state caused by the expansion and contraction of each layer during processing.

[0041] Such warping of the substrate S causes variations in the gap between it and the hot plate 20. Deviations in the distance from the heat source lead to uneven heating of the coated film F, resulting in film quality deviations. Therefore, a correction mechanism 40 is provided in the substrate processing apparatus 1 to correct such warping of the substrate S and bring it closer to a flat state.

[0042] The straightening mechanism 40 consists of multiple straightening pins 41 mounted on the inner top surface 111 of the cover 11 via adjusting nuts 42. If the substrate S is warped, the straightening pins 41 abut against the upper surface Sa of the substrate S from above to correct the warping when the cover 11 is closed. "Straightening" does not mean making the substrate S perfectly flat; its purpose is to suppress the deviation in the gap between the substrate S and the hot plate 20 to the extent that uneven heating is avoided. Therefore, it is not necessary for all the straightening pins 41 to abut against the substrate S.

[0043] By individually adjusting the screwing depth of the straightening pin 41 screwed to the adjusting nut 42, the vertical position of the lower end of each straightening pin 41 can be changed. This allows for alignment of the Z-direction positions of the lower ends of each straightening pin 41, and enables appropriate straightening of substrates S of various thicknesses.

[0044] An exhaust through-hole 121 and a purification through-hole 122 are provided on the bottom plate 12 of the chamber 10. An exhaust pipe 51 for the exhaust section 50 is connected to the exhaust through-hole 121. A purification pipe 52 for the exhaust section 50 is connected to the purification through-hole 122. The exhaust pipe 51 is connected to an exhaust line (not shown) via an exhaust valve 53 and a pump 54. The purification pipe 52 is connected to a purification gas source (not shown) via a purification valve 55.

[0045] The exhaust section 50 is controlled by the atmosphere control section 97 of the control section 90. Specifically, based on the control signal from the atmosphere control section 97, the exhaust valve 53 and the pump 54 are activated to discharge the gas in the chamber 10, thereby reducing the pressure in the processing space SP. Additionally, based on the control signal from the atmosphere control section 97, the purification valve 55 is activated to introduce purified gas from an external gas source into the processing space SP. Thus, by operating the exhaust section 50 according to the control signal from the atmosphere control section 97, the atmosphere within the processing space SP is controlled.

[0046] An upper heater 16 is provided on the upper surface 112 of the cover portion 11. The upper heater 16 receives power supplied from the upper heater control unit 96 of the control unit 90 and heats up to heat the top plate of the cover portion 11. The cover portion 11 is heated as needed, thereby preventing components volatilized from the coating film F from contacting the low-temperature cover portion 11 and precipitating out and dripping onto the substrate S.

[0047] Furthermore, a lower heater 15 is provided on the lower surface of the base plate 12. The lower heater 15 receives power supplied from the lower heater control unit 95 of the control unit 90 and heats up to heat the base plate 12. As will be described in detail later, the lower heater 15 has the function of assisting in heating the periphery of the substrate S from below via the base plate 12, thereby reducing the temperature unevenness of the substrate S.

[0048] Figures 2A to 2C This diagram schematically illustrates the operation of each part when a substrate is moved into the chamber. As described above, in this substrate processing apparatus 1, the substrate S can be received from the outside when the cover 11 constituting the chamber 10 is retracted upwards. Specifically, the chamber drive unit 93 moves the cover 11 upwards, thereby enabling the substrate S to be received from the outside. Figure 2A As shown, the cover portion 11 and the base portion 12 are moved apart in the vertical direction.

[0049] In this state, the substrate S can be moved in from the side. That is, the substrate S is placed on the arm H and moved into the substrate processing apparatus 1 through the gap between the cover 11 and the base plate 12, wherein the arm H is provided on an external handling robot. At this time, in order to avoid interference with the arm H, it is preferable that the lifting pin 32 is lowered to the lower position.

[0050] like Figure 2BAs shown, during the stage where the substrate S is transferred to a predetermined position, the lifting pin 32 rises to abut against the lower surface Sb of the substrate S, thereby transferring the substrate S from the arm H to the lifting pin 32. Figure 2C As shown, after the handover, the arm H retracts to the side, and the lifting pin 32 descends to the lower position, thereby horizontally supporting the substrate S with a specified gap between it and the hot plate 20.

[0051] like Figure 2C As shown by the dashed arrow, the cover 11 descends from this state, thus, as Figure 1 As shown, the cover 11 and the base plate 12 are joined by a sealing member 13. This creates a closed processing space SP. At this time, the correction pin 41, which is adjusted according to the height of the upper surface Sa of the substrate S, abuts against the substrate S, thereby correcting the warping of the substrate S. In addition, by performing the opposite action, the substrate S can be removed from the chamber 10.

[0052] Figure 3A and Figure 3B This is a diagram showing the configuration of the lifting pins and the straightening pins. Figure 3A The figure shows the positional relationship between the substrate S and the lifting pins 32 and the straightening pins 41 when viewed from above. More specifically, the position where the lifting pins 32 abut against the substrate S, which is supported horizontally, from the lower surface side is indicated by a white circle. The position where the straightening pins 41 abut against the substrate S from the upper surface side is indicated by a shaded circle. As shown in the figure, multiple lifting pins 32 are arranged at a certain spacing to distribute the load on the substrate S and support it. On the other hand, multiple straightening pins 41 are arranged at a certain spacing outside the region Rp where the lifting pins 32 are arranged. Therefore, the straightening pins 41 abut against the substrate S at a position further outward than where the lifting pins 32 abut against the substrate S. Furthermore, the arrangement of the lifting pins 32 within region Rp and the arrangement of the straightening pins 41 outside region Rp are not limited to this.

[0053] The reason for this arrangement is as follows. In the substrate processing apparatus 1 of this embodiment, the substrate S supplied for processing is, for example, a substrate on which semiconductor circuits or other devices are laminated on the upper surface of a glass substrate. Figure 3B As shown, in such substrates, due to the different thermal expansion rates of the materials, the periphery of the substrate S often warps upwards, and the entire substrate S forms a downward convex curved surface.

[0054] In this situation, if the substrate S is supported from below solely by the lifting pin 32, allowing it to warp, the gap between the periphery of the substrate S and the hot plate 20 will be larger than the gap between its center and the hot plate 20. This will cause the distance between the periphery of the substrate S and the hot plate 20, which serves as a heat source, to increase, resulting in insufficient heating. By placing the corrective pin 41 against the upper surface of the substrate S at a position further outward than the area Rp supported from below by the lifting pin 32, it is possible to achieve... Figure 3B As shown by the dotted line, the warping of the periphery of the substrate S is pressed from above, making the substrate S close to a flat state.

[0055] As described in Patent Document 1, in the heat drying process performed under reduced pressure to allow partial evaporation of the solvent components in the coated film, a certain degree of curing of the coated film occurs before heating. Therefore, such uneven heating has a relatively small impact on the quality of the fully dried coated film. On the other hand, as in this embodiment, in the heat-reduced pressure drying process where the substrate is received in a undried state with the coated film, the film quality deviation caused by uneven heating of the liquid coated film becomes more pronounced. Therefore, the above-described countermeasure to reduce uneven heating by correcting the warpage of the substrate S is particularly effective.

[0056] To address the issue of insufficient heating at the periphery of the substrate S, the substrate processing apparatus 1 of this embodiment also includes a lower heater 15 disposed on the bottom plate portion 12 of the chamber 10. Figure 1 The lower heater 15 provides auxiliary heating to the substrate S by heating the base plate portion 12, based on the heating of the substrate S by the internal heater within the hot plate 20.

[0057] When the hot plate 20 is heated by the internal heater, the temperature may not rise sufficiently, especially at the periphery where heat easily dissipates, compared to the center of the hot plate 20. Therefore, even if the distance between the hot plate 20 and the substrate S is kept constant, uneven heating occurs at the periphery of the substrate S due to insufficient heating. In the case of a rectangular substrate S, this problem of insufficient heating is particularly prone to occur near its four corners.

[0058] While adding temperature detection points to the hot plate 20 or designing the heating mode of the heater may improve the situation, interference between control points can cause temperature instability. To address this problem, in this substrate processing apparatus 1, a lower heater 15 is provided to selectively heat the periphery of the substrate S, thereby resolving the temperature difference issue with the center.

[0059] Figure 4 This is a diagram illustrating an example of the configuration of the lower heater. (Example) Figure 4As shown in the two examples marked with symbols (a) and (b), the lower heater 15 is positioned on the lower surface of the base plate 12 at a location corresponding to the periphery of the substrate S disposed above it. Specifically, in... Figure 4 In the example shown in (a), the lower heater 15 has four heating elements 15a to 15d, each heating element 15a to 15d corresponding to one of the four vertices of the substrate S and configured to cover the area directly below and around each vertex. On the other hand, in Figure 4 In the example shown in (b), a rectangular annular lower heater 15 is provided to cover the peripheral area directly below the four sides of the periphery of the contact substrate S.

[0060] In these structures, the peripheral portion of the substrate S, which is cooler than the center of the substrate S, can be heated by energizing the lower heater 15 as needed. Heating can be performed directly by radiant heat from the base plate portion 12, which has been heated by the lower heater 15, or indirectly by radiant heat to the peripheral portion of the hot plate 20. As a result, the coating film F can be dried uniformly over the entire substrate, and the dried coating film F can be of uniform and high quality.

[0061] To prevent contaminants such as particles generated by the lower heater 15 from adhering to the substrate S, it is preferable that the lower heater 15 is positioned closer to the bottom than the substrate S. The same applies to the internal heater, but for the internal heater (specifically, the heat plate 20 built into it), which serves as the heating body of the substrate S, it needs to be positioned close to the substrate S within the chamber 10.

[0062] On the other hand, the lower heater 15 only auxiliaryly heats the periphery of the substrate S, so it does not need to be positioned close to the substrate S. As described in this embodiment, the lower heater 15 can also be provided on the outer side of the chamber 10, for example, on the lower surface of the base plate 12. In this way, by separately configuring the heating plate 20 and the lower heater 15, it is possible to prevent instability in temperature distribution caused by mutual interference between the individual temperature controls. However, in order to obtain a sufficient heating effect, it is preferable that the set target temperature of the lower heater 15 is higher than the set target temperature of the internal heater.

[0063] Figure 5 This is a flowchart illustrating the heating and depressurization drying process performed by the substrate processing apparatus. This process is achieved by executing a pre-prepared control program through the CPU 91 of the control unit 90, causing each part of the apparatus to perform predetermined actions. The hot plate 20 is preheated to a predetermined temperature (step S101). Additionally, the upper heater 16 and the lower heater 15 are also heated as needed.

[0064] Then, the lifting pin 32 is positioned at the lower position, causing the cover 11 to move upward to form an open state (step S102), thus creating a state where the substrate S can be received. In this state, the untreated substrate S (i.e., loaded with an undried coating film F) is brought in by an external handling robot, and the lifting pin 32 is raised to the upper position, thereby receiving the substrate S from the arm H of the handling robot (step S103). Furthermore, the loading and unloading of the substrate S is not limited to being operated by a handling robot, but can be done by any method using a suitable handling mechanism capable of horizontally handling the substrate.

[0065] The handling robot arm retracts, and the lifting pin 32 descends to a lower position (step S104), thereby positioning the substrate S at the processing position, that is, above the preheated hot plate 20 at a predetermined gap. Furthermore, the cover 11 descends, closing the processing space SP, and the corrective pin 41 mounted on the cover 11 abuts against and presses against the upper surface Sa of the substrate S, thereby correcting the warping of the substrate S (step S105).

[0066] Then, the exhaust section 50 is operated to reduce the pressure on the processing space SP (step S106). By reducing the pressure on the processing space SP where the substrate S is housed, in conjunction with heating, the evaporation of solvent components in the coating film F is promoted, and the coating film F is dried. At this time, the periphery of the substrate S is heated by the lower heater 15, thereby enabling uniform drying on the substrate S.

[0067] After heating the substrate S and depressurizing the surrounding space for a predetermined time (step S107), the exhaust unit 50 stops exhausting and instead introduces purification gas (step S108), thereby releasing the depressurization state of the processing space SP. Then, the cover 11 moves upward, exposing the substrate S in the processing space SP to the external space (step S109), and the lifting pin 32 rises, causing the substrate S to retract upward from the hot plate 20 (step S110). Subsequently, the substrate S is received by an external handling robot, thereby moving the dried substrate S to the outside (step S111).

[0068] If there is a next substrate S to be processed (yes in step S112), the process returns to step S102 to receive a new substrate S and performs the same process as described above. On the other hand, if there is no new substrate S (no in step S112), the process can be terminated by a predetermined termination action.

[0069] As described above, the substrate processing apparatus 1 of this embodiment receives a substrate S with an undried coating film F formed on it into the chamber 10, and performs a heat-pressure drying process on the coating film F within the chamber 10. In this case, the lifting pin 32 abuts against the lower surface Sb side of the substrate S, while the straightening pin 41 abuts against the upper surface Sa side of the substrate S, thereby correcting the warpage of the substrate S to a near-planar state. As a result, the quality deviation of the dried coating film F caused by uneven heating due to local deviation of the substrate S from the hot plate 20 can be reduced.

[0070] In addition, a lower heater 15 is provided below the substrate S to assist in heating the periphery of the substrate S. Therefore, it is possible to suppress the temperature difference between the periphery and the center of the substrate S, and further reduce the quality deviation of the coating film F caused by uneven heating.

[0071] It should be noted that the present invention is not limited to the above-described embodiments, and various modifications beyond the above content can be made as long as they do not depart from its spirit. For example, in the above embodiments, sixteen lifting pins 32 are arranged in the central region Rp of the substrate S, and sixteen straightening pins 41 are arranged to surround its outer side. However, these configurations are merely examples, and appropriate changes and applications can be made to the configurations beyond these.

[0072] In addition, the correction pin 41 in the above embodiment abuts against the substrate S at a position closer to the outer side than the lifting pin 32, but it is not limited to this. For example, the correction pin can be arranged at the same position as the outermost lifting pin, that is, at a position corresponding to the outer edge of the region Rp, to abut against the substrate.

[0073] Furthermore, in the above embodiments, both the lifting pin 32 and the straightening pin 41 have small front ends that abut against the substrate S. However, among the components that abut against the lower surface to support the substrate S and the components that abut against the upper surface to correct warping, at least one of them may be, for example, a rod-shaped or plate-shaped component that abuts against the substrate with an area larger than that of a pin-shaped component.

[0074] Furthermore, in the above embodiment, the chamber 10 is covered by a cover 11 with a lower opening, which covers the upper part of the flat bottom plate 12, thereby forming a processing space SP. Alternatively, a flat cover member can be used to close the upper part of a box-shaped frame with an upper opening.

[0075] In addition, the upper heater 16 and the lower heater 15 in the above embodiments can be energized as needed, or a drying process can be implemented without using at least one of them.

[0076] Furthermore, the above embodiments are based on rectangular substrates, and the shape of the hot plate and the arrangement of the lifting pins and straightening pins are also based on rectangular substrates. However, the substrate to which this invention is applicable is not limited to rectangular. For example, even circular substrates or irregularly shaped substrates with uneven outer edges can be processed by appropriately changing the shape and arrangement of each part.

[0077] As explained above, in the substrate processing apparatus 1 of this embodiment, the lifting pin 32 functions as a "support part" of the present invention, and the straightening pin 41 functions as a "straightening member" of the present invention. Furthermore, the hot plate 20 functions as a "heating part" of the present invention, and the lower heater 15 functions as a "second heating part." Additionally, the exhaust part 50 functions as a "pressure relief part" of the present invention. Furthermore, the cover part 11 corresponds to the "upper unit" of the present invention, and the bottom plate part 12 corresponds to the "lower unit," together forming the "chamber" of the present invention. Finally, the adjusting nut 42 functions as an "adjustment mechanism" of the present invention.

[0078] The above examples illustrate and explain specific embodiments. In this invention, the heating section includes a hot plate that is controlled to be heated to a predetermined temperature. The planar dimension of the upper surface of the hot plate is greater than or equal to that of the substrate. The support section can be a structure that supports the substrate facing each other with the upper surface of the hot plate separated by a predetermined gap. With such a structure, the substrate S can be uniformly heated by radiant heat from the heated plate whose temperature is controlled.

[0079] Alternatively, for example, a second heating element can be provided at a position lower than the supported substrate within the chamber to heat the periphery of the substrate. With this structure, the periphery of the substrate, which is more prone to temperature fluctuations than the center, is heated by the second heating element, thereby eliminating the temperature difference with the center and enabling uniform drying.

[0080] In this configuration, the second heating element can heat the bottom of the chamber. With this structure, the second heating element is positioned away from the heating element that directly heats the substrate. The second heating element indirectly heats the substrate via the bottom of the chamber. This prevents the temperature control of the two heating elements from interfering with each other, thus avoiding problems such as a complex or unstable temperature distribution on the substrate.

[0081] Furthermore, for example, the support portion can support the substrate and allow it to move up and down. With this structure, the distance between the substrate and the heating portion can be varied. Therefore, for example, operations for moving the substrate into and out of the chamber can be easily performed.

[0082] Alternatively, for example, the chamber may have a lower unit equipped with a support and a heating element, and an upper unit equipped with a corrective member. The upper unit engages with the lower unit, closing the upper part of the lower unit to form a processing space. In this case, the upper unit engages with the lower unit, and the lower end of the corrective member is positioned at a height corresponding to the vertical position of the upper surface of the substrate supported by the support. With this structure, the operation of engaging the upper and lower units to form the processing space also includes pressing the substrate with the corrective member to correct warping, thus shortening the processing time.

[0083] In this case, an adjustment mechanism can be further provided to adjust the vertical position of the lower end of the correction member when the upper and lower units are engaged. This allows the same apparatus to process substrates of varying thicknesses. In other words, by providing this adjustment mechanism, the substrate processing apparatus can handle substrates of various thicknesses.

[0084] Additionally, for example, the corrective member can abut against the periphery of the upper surface of the substrate. More specifically, when viewed from above, the corrective member can abut against the substrate at a position further outward than the area of ​​the substrate supported by the support portion. With such a structure, it is possible to correct the upward warping of the substrate at its periphery, thereby making it nearly flat.

[0085] Industrial availability

[0086] This invention is universally applicable to substrate processing techniques in which a coating liquid is applied to a surface and dried to form a coating film layer on the substrate surface.

Claims

1. A substrate processing apparatus for drying a coating film formed on the main surface of a substrate by heating the substrate and depressurizing the space surrounding it, wherein... The substrate processing apparatus includes: The chamber has a processing space capable of storing the substrate in a horizontal position; The support portion, within the processing space, abuts against the lower surface of the substrate and supports the substrate from below; The corrective member partially abuts against the upper surface of the substrate supported by the support portion, thereby correcting the warping of the substrate; The first heating section heats the lower surface of the substrate supported by the support section within the processing space. The second heating unit heats the periphery of the substrate by heating the bottom of the chamber from outside the processing space; as well as The pressure relief unit reduces the pressure in the processing space.

2. The substrate processing apparatus according to claim 1, wherein, The first heating element has a hot plate that is controlled to be heated to a predetermined temperature, and the planar dimension of the upper surface of the hot plate is greater than or equal to that of the substrate. The support portion faces the substrate and the upper surface of the hot plate at a predetermined gap, and supports the substrate.

3. The substrate processing apparatus according to claim 1 or 2, wherein, The substrate processing apparatus processes a rectangular substrate. The second heating element has four heating elements corresponding to the four vertices of the substrate, and each heating element is positioned directly below the corresponding vertex and its surrounding area on the lower surface of the bottom of the chamber.

4. The substrate processing apparatus according to claim 1 or 2, wherein, The substrate processing apparatus processes a rectangular substrate. The second heating unit has a rectangular annular heater positioned directly below the periphery of the substrate in the lower surface of the bottom of the chamber and its surrounding area.

5. The substrate processing apparatus according to claim 1 or 2, wherein, The support portion supports the substrate and allows the substrate to move up and down.

6. The substrate processing apparatus according to claim 1 or 2, wherein, The chamber has a lower unit and an upper unit. The lower unit is provided with the support portion and the first heating portion, and the upper unit is provided with the corrective member. The upper unit and the lower unit can engage, with the upper unit closing the upper part of the lower unit, thereby forming the processing space. If the upper unit engages with the lower unit, the lower end of the corrective member is positioned at a height corresponding to the vertical position of the upper surface of the substrate supported by the support portion.

7. The substrate processing apparatus according to claim 6, wherein, The substrate processing apparatus includes an adjustment mechanism for adjusting the vertical position of the lower end of the correction member when the upper unit and the lower unit are engaged.

8. The substrate processing apparatus according to claim 1 or 2, wherein, The corrective member abuts against the periphery of the upper surface of the substrate.

9. The substrate processing apparatus according to claim 8, wherein, When viewed from above, the corrective member abuts against the substrate at a position further outward than the area of ​​the substrate supported by the support portion.

10. A substrate processing method, comprising heating a substrate and depressurizing its surrounding space to dry a coating film formed on the main surface of the substrate, wherein, The substrate processing method includes: In a processing space chamber where a first heating unit for heating the substrate is disposed, a support portion abuts against the lower surface of the substrate and supports the substrate above the first heating unit at a predetermined gap. The second heating unit heats the bottom of the chamber from outside the processing space, thereby heating the periphery of the substrate. The corrective member partially abuts against the upper surface of the substrate supported by the support portion, thereby correcting the warpage of the substrate. The processing space is depressurized and the substrate is heated by the first heating unit and the second heating unit to dry the coating film.

11. The substrate processing method according to claim 10, wherein, The first heating element has a hot plate that is controlled to be heated to a predetermined temperature, and the planar dimension of the upper surface of the hot plate is greater than or equal to that of the substrate. The support portion faces the substrate and the upper surface of the hot plate at a predetermined gap, and supports the substrate.

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