TW202336397A - Depressurization drying device, depressurization drying method, and method for shortening time required for depressurization drying process - Google Patents

Abstract

Provided is a depressurization drying device that dries a solution on a substrate in a depressurized state, wherein said device comprises a processing container that is configured to be depressurizable and that contains a substrate, a mounting base which is provided in the processing container and on which the substrate is mounted, a solvent-collecting part that collects a solvent in the solution vaporized from the substrate and discharged into the processing container along with a depressurization drying process, and a cooling part that cools the solvent-collecting part heated when the depressurized state in the processing container is terminated.

Description

Reduced pressure drying device, reduced pressure drying method, and method of shortening the time required for reduced pressure drying

This disclosure relates to a reduced pressure drying device, a reduced pressure drying treatment method, and a method for shortening the time required for the reduced pressure drying treatment.

Patent Document 1 discloses a reduced pressure drying device that dries an organic material applied to a substrate under reduced pressure. Patent Document 2 discloses a vacuum drying device provided with a solvent collection unit that is opposed to a substrate placed on a stage and temporarily collects the solvent in a solution that vaporizes from the substrate. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2017-73338 [Patent Document 2] Japanese Patent Application Publication No. 2020-190405

[Problem to be solved by the invention]

The technology disclosed in the present disclosure shortens the time required for the post-processing procedure in the vacuum drying process and shortens the overall time required for the vacuum drying process. [Technical means to solve problems]

One aspect of the present disclosure is a reduced pressure drying device that dries a solution on a substrate under reduced pressure, and includes: a processing container configured to be decompressible and accommodating the substrate; and a stage provided on In the processing container, the substrate is placed; a solvent collection part that collects the solvent that is vaporized from the substrate during the reduced pressure drying process and is released into the solution in the processing container; and a cooling part that will be used in the processing container. The solvent collecting part whose temperature has been raised when the depressurized state in the processing container is released is cooled. [Invention effect]

According to the present invention, the time required for the post-processing procedure in the vacuum drying process can be shortened, and the time required for the entire vacuum drying process can be shortened.

Conventionally, an organic light emitting diode (OLED: Organic Light Emitting Diode) is known, which is a light emitting diode that utilizes the light emission of organic EL (Electroluminescence). Organic EL displays using these organic light-emitting diodes have attracted attention as a next-generation flat panel display (FPD) in recent years because they are thin, lightweight, consume low power, and have excellent response speed, viewing angle, and contrast. .

The organic light-emitting diode has a structure in which an organic EL layer is sandwiched between an anode and a cathode on a substrate. The organic EL layer is formed, for example, by laminating a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in order from the anode side. When forming each layer of these organic EL layers (especially the hole injection layer, the hole transport layer and the light-emitting layer), for example, the following method is used: pairs of droplets of organic material are discretely arranged on the substrate using an inkjet method. The partition wall corresponding to the pixel of each color is spit out, and the film of the organic material of the pixel is coated in the partition wall.

The organic material discharged onto the substrate by the inkjet method contains a large amount of solvent. Therefore, in order to remove the solvent, a reduced pressure drying process is performed to dry the solution on the substrate under reduced pressure. This reduced-pressure drying process is performed using a reduced-pressure drying device including a processing container configured to be depressurized and a stage for a substrate provided in the processing container (see Patent Documents 1 and 2).

In addition, in the reduced pressure drying device disclosed in Patent Document 2, a solvent collection unit that temporarily collects the solvent vaporized from the substrate placed on the stage is provided in the processing container, so that the solvent on the substrate is removed. The solvent removal process, that is, the time required for the substrate drying process of drying the solution on the substrate is shortened, and the time required for the vacuum drying process is shortened.

However, nowadays, it is necessary to shorten the time required for the entire vacuum drying process. Although the shortening of the time required for the substrate drying process due to the installation of the above-mentioned solvent collection part, etc. is related to the shortening of the overall time required for the reduced pressure drying process, in the reduced pressure drying process, after the above-mentioned substrate drying process, There are various procedures (hereinafter, post-treatment procedures), and the post-treatment procedures also have an impact on the time required for the reduced pressure drying process. In addition, in the post-processing process, for example, the solvent adsorbed to the components of the reduced pressure drying device (for example, the processing container) during the substrate drying process is desorbed.

The technology disclosed in the present disclosure shortens the time required for the post-processing process in the vacuum drying process and shortens the time required for the entire vacuum drying process.

Hereinafter, the reduced pressure drying device, the reduced pressure drying method, and the method of shortening the time required for the reduced pressure drying process of the present disclosure will be described with reference to the drawings. In addition, in this specification and the drawings, elements having substantially the same functional configuration are denoted by the same reference numerals, and repeated descriptions will be omitted.

[1st way] ＜Pressure reduction drying device＞ Figures 1 to 3 are diagrams illustrating the schematic structure of the vacuum drying device of the first mode. Figure 1 is a schematic cross-sectional view of the vacuum drying device. Figures 2 and 3 are respectively Figure 1 A-A line cross-sectional view and B-B line cross-sectional view. Fig. 4 is a partially enlarged plan view of a solvent collection unit described later.

The reduced pressure drying device 1 dries a solution applied on the substrate G by, for example, an inkjet method under reduced pressure. In addition, the substrate G to be processed by the reduced pressure drying device 1 is, for example, a glass substrate for an organic EL display, and its planar size is 2.2 m×2.7 m.

The solution applied to the substrate G to be processed is composed of a solute and a solvent, and the component to be subjected to the reduced pressure drying process is mainly the solvent. Among the organic compounds contained in the solvent, many have high boiling points. Examples include 1,3-dimethyl-2-imidazolidinone (boiling point 220°C, melting point 8°C), 4 -Tertiary butyl anisole (4-tert-Butylanisole, boiling point 222°C, melting point 18°C), trans-Anethole (trans-Anethole, boiling point 235°C, melting point 20°C), 1,2-dimethoxy Benzene (1,2-Dimethoxybenzene, boiling point 206.7℃, melting point 22.5℃), 2-Methoxybiphenyl (boiling point 274℃, melting point 28℃), Phenyl Ether (boiling point 258.3℃, melting point 28℃), 2-Ethoxynaphthalene (boiling point 282℃, melting point 35℃), Benzyl Phenyl Ether (boiling point 288℃, melting point 39℃), 2,6-dimethoxytoluene (2,6-Dimethoxytoluene, boiling point 222℃, melting point 39℃), 2-Propoxynaphthalene (boiling point 305℃, melting point 40℃), 1,2,3-trimethoxybenzene (1,2 , 3-Trimethoxybenzene, boiling point 235℃, melting point 45℃), cyclohexylbenzene (boiling point 237.5℃, melting point 5℃), dodecylbenzene (dodecylbenzene, boiling point 288℃, melting point -7℃), 1,2 , 3,4-tetramethylbenzene (1,2,3,4-tetramethylbenzene, boiling point 203°C, melting point 76°C), etc. These high boiling point organic compounds may be combined into two or more types and mixed in a solution.

As shown in FIGS. 1 to 3 , the reduced pressure drying device 1 includes a chamber 10 as a processing container.

The chamber 10 is a container configured to be decompressible, and is made of a metal material such as stainless steel. The substrate G is accommodated in the chamber 10 . Inside the chamber 10, a stage 20 on which the substrate G is mounted and a solvent collection unit 50 described below are provided. In addition, the chamber 10 has side walls 11 , a top plate 12 , and a bottom plate 13 .

The side wall 11 surrounds the stage 20 when viewed from the thickness direction (Z direction in FIG. 1 ) of the solvent collection part 50 to be described later. The side wall 11 is formed, for example, in a prism shape, with openings formed on the upper and lower sides. As shown in FIG. 3 , the side wall 11 is provided with an unloading entrance 11 a on the negative side in the X direction for loading and unloading the substrate G into and out of the chamber 10 . The carry-out entrance 11a is openable and closable via the gate valve 14. The gate valve 14 is controlled by a control unit U described below.

The top plate 12 is attached to the upper side of the side wall 11 so as to block an upper opening formed through the side wall 11 .

The bottom plate 13 is attached to the lower side of the side wall 11 so as to block a lower opening formed through the side wall 11 . A stage 20 is provided at the center of the upper surface of the bottom plate 13 . The stage 20 is provided with a lifter (not shown) for transferring the substrate G between the stage 20 and an external transport device. This tappet is configured to be freely raised and lowered through a lifting mechanism (not shown). The above-mentioned lifting mechanism is controlled by a control unit U described below.

In addition, as shown in FIG. 1 , the bottom plate 13 is provided with a plurality of exhaust ports 13 a and 13 b along the outer periphery of the stage 20 . In this example, two exhaust ports 13 a are provided along the long side of the stage 20 on the negative side in the Y direction, and two exhaust ports 13 a are provided along the long side of the stage 20 on the positive side in the Y direction. In addition, in this example, three exhaust ports 13 b are provided along the short side of the stage 20 on the negative side in the X direction, and three exhaust ports 13 b are provided along the short side of the stage 20 on the positive side in the X direction.

As shown in FIG. 2 , an exhaust mechanism 31 for depressurizing the chamber 10 is connected to the exhaust port 13 a via an exhaust pipe 32 . The exhaust mechanism 31 includes a dry pump 31a that exhausts the inside of the chamber 10, a switching valve (not shown) that switches the start/stop of exhaust through the dry pump 31a, and the like. The exhaust port 13a, the exhaust mechanism 31 (specifically, the portion of the exhaust mechanism 31 that connects the exhaust pipe 32 and the dry pump 31a), and the exhaust pipe 32 constitute the exhaust line 30. The exhaust line 30 is connected to the dry pump 31 a and exhausts the chamber 10 .

A protective net 33 is provided on the exhaust line 30 . The protective net 33 prevents objects from intruding into the dry pump 31a through the exhaust line 30, and is formed in a mesh shape to protect the dry pump 31a. The material of the protective net 33 is stainless steel, for example. In this example, the protective net 33 is provided to cover the side end of the chamber 10 of the exhaust port 13a.

As shown in FIG. 3 , an exhaust mechanism 41 is connected to the exhaust port 13 b via an exhaust pipe 42 . The exhaust mechanism 41 further depressurizes the chamber 10 depressurized by the exhaust mechanism 31, and has a turbomolecular pump 41a for further exhausting the chamber 10, and an exhaust gas that is switched through the turbomolecular pump 41a. Gas start/stop switching valve (not shown), etc. The exhaust port 13b, the exhaust mechanism 41 (specifically, the portion of the exhaust mechanism 41 that connects the exhaust pipe 42 and the turbomolecular pump 41a), and the exhaust pipe 42 constitute the exhaust line 40. The exhaust line 40 is connected to the turbomolecular pump 41 a and exhausts the inside of the chamber 10 .

A protective net 43 is provided on the exhaust line 40 . The protection net 43 prevents objects from intruding into the turbomolecular pump 41a through the exhaust line 40 and is formed in a mesh shape to protect the turbomolecular pump 41a. The material of the protection net 43 is stainless steel, for example. In this example, the protective net 43 is provided to cover the side end of the chamber 10 of the exhaust port 13b.

In addition, the protective nets 33 and 43 do not capture small objects such as particles that may cause defects in the substrate G, but capture relatively large objects (eg, screws, etc.) whose length and diameter are, for example, 1 mm or more. In addition, although the solvent collecting part 50 described later is also formed in a mesh shape like the protective nets 33 and 43, the openings and opening ratios of the mesh portions of the protective nets 33 and 43 are relatively large. The protective nets 33 and 43 The opening is, for example, 1~5mm square.

The exhaust mechanisms 31 and 41 are controlled by a control unit U described below. In addition, a pressure gauge (not shown) for measuring the pressure in the chamber 10 is provided in the chamber 10 in order to adjust the exhaust gas passing through the exhaust mechanisms 31 and 41 .

Furthermore, a solvent collection part 50 is provided inside the chamber 10 . The solvent collecting unit 50 temporarily collects the solvent in the solution that has evaporated from the substrate G placed on the stage 20 . The solvent trap 50 is provided above the substrate G placed on the stage 20 in the chamber 10 so as to face the substrate G. Specifically, the solvent trap 50 is provided in the chamber 10 so as to face the substrate G placed on the stage 20 , that is, substantially parallel to the substrate G placed on the stage 20 .

The solvent collecting part 50 is a mesh-shaped member, more specifically, a mesh-shaped member. As shown in FIG. 4 , it has a plurality of holes penetrating the solvent collecting part 50 in the thickness direction (the Z direction in FIG. 4 ). Through hole 50a. The through-holes 50a are formed in a lattice shape across the entire surface of the solvent collection part 50 in a plan view (viewed in the Z direction of FIG. 3).

As for the material of the solvent collecting part 50, a material with good thermal conductivity, such as a metal material such as stainless steel, is used. In addition, the solvent collecting part 50 is formed to be thin, and is formed to have a thickness of, for example, 0.05 mm to 0.2 mm. When viewed from above, the size of the solvent collecting part 50 is substantially the same as the size of the stage 20 . The solvent collecting portion 50 has an opening ratio of 60% to 90% and a thickness of 0.05 to 0.2 mm as mentioned above. Therefore, the heat capacity is small. Therefore, when the pressure in the chamber 10 is reduced and the gas in the chamber 10 is cooled due to adiabatic expansion, the solvent trap 50 is cooled by the cooled gas. The opening ratio of the solvent collecting part 50 is determined by (the total area of the through holes 50 a of the solvent collecting part 50 in a plan view)/(the total area of the solvent collecting part 50 in a plan view).

In addition, the solvent collecting part 50 is subjected to processing for increasing the radiation rate of the solvent collecting part 50 (hereinafter, may be referred to as radiation rate increasing treatment). The radiation rate increasing process is, for example, a process of blackening the solvent collection part 50 . More specifically, for example, when the solvent trap 50 is formed of stainless steel, the stainless steel is oxidized. In addition, the emissivity increasing treatment is a roughening treatment performed on the surface of the solvent trap portion 50 formed of a metal material. The roughening process forms numerous fine irregularities on the surface of the solvent collection portion 50 made of a metal material, thereby increasing the radiation rate of the solvent collection portion 50 . The roughening treatment is performed using, for example, sandpaper.

The solvent trap 50 is produced by, for example, forming a plurality of through holes 50 a in a plate material made of stainless steel or the like by drilling using laser processing, plasma etching, etc., and then performing a radiation rate increasing process. . Alternatively, a plurality of mesh-shaped members may be combined to form one solvent collection unit 50 .

As shown in FIGS. 2 and 3 , the solvent collection unit 50 is supported on the bottom plate 13 via a plurality of support members 60 . Each support member 60 is a member extending in the vertical direction, and supports the solvent collection part 50 at its top end. The base end of each support member 60 is connected to a lifting mechanism (not shown) for lifting and lowering the support member 60 . The lifting mechanism has a driving source (not shown) such as a motor that generates a driving force for lifting the support member 60 . By raising and lowering the support member 60, the solvent collecting part 50 can be positioned between the first height position shown by the solid line in FIGS. 2 and 3 and the position higher than the first height position shown by the dotted line in FIGS. 2 and 3. The solvent collecting part 50 is raised and lowered between the illustrated second height positions. The above-mentioned first height position (hereinafter, abbreviated as "first position") is the position when the solvent is removed from the substrate G, and the above-mentioned second position (hereinafter, abbreviation as "second position") is between the stage 20 and the outside. The position when the substrate G is transferred between transfer devices. In addition, the raising and lowering mechanism of the support member 60 is controlled by the control unit U described later.

In addition, the reduced pressure drying device 1 has a control unit U. This control unit is, for example, a computer equipped with a CPU, a memory, etc., and has a program storage unit (not shown). In the program storage unit, a program for controlling the reduced pressure drying process in the reduced pressure drying device 1 is stored. In addition, the above-mentioned program may be recorded in a computer-readable non-transitory storage medium H and may be installed in the above-mentioned control unit from the storage medium H. Part or all of the program can also be implemented with dedicated hardware (circuit substrate).

＜Reduced pressure drying＞ Next, the reduced pressure drying process using the reduced pressure drying device 1 will be described using FIGS. 5 and 6 . FIG. 5 is a flow chart illustrating an example of the reduced pressure drying process using the reduced pressure drying device 1 . FIG. 6 is a diagram illustrating the time change of the pressure in the chamber 10 when the radiation rate increasing process is not performed on the solvent collection part 50 of the reduced pressure drying device 1 . In FIG. 6 , the horizontal axis represents time and the vertical axis represents the pressure in the chamber 10 . The pressure aspect is shown on a logarithmic scale. In addition, the following reduced pressure drying process is performed under the control of the control unit U. In addition, in the following example, it is assumed that the substrate G has been carried into the chamber 10 and placed on the stage 20 when the reduced pressure drying process is started.

(S1: Substrate drying procedure) First, the solution placed on the substrate G on the stage 20 is dried, that is, the solvent in the solution on the substrate G is removed.

Specifically, as shown in FIG. 6 , the pressure inside the chamber 10 is reduced, and the solvent on the substrate G placed on the stage 20 is removed in a reduced pressure state. At the same time, through the pressure reduction in the chamber 10, the gas in the chamber 10 undergoes adiabatic expansion and is cooled. Due to the gas, the solvent collection part 50 is cooled, and through the solvent collection part 50, the gas in the chamber 10 is cooled. The vaporized solvent of the substrate G placed on the stage 20 is temporarily captured. This procedure is explained in more detail below. In addition, in this process, the position of the solvent collecting part 50 is the aforementioned first position.

First, the dry pump 31a is activated to depressurize and exhaust the chamber 10 . The decompression exhaust through the dry pump is performed until the pressure in the chamber 10 becomes, for example, 10 Pa. During this decompression and exhaust process, the gas in the chamber 10 is cooled due to adiabatic expansion. Even if the gas in the chamber 10 is cooled in this way, the temperature of the substrate G is not affected by the cooled gas due to the large heat capacity of the substrate G, and hardly changes from the room temperature of 23°C. However, the solvent trap portion 50 having a small heat capacity is cooled by the gas that is cooled due to adiabatic expansion as the pressure is reduced.

After that, the turbomolecular pump 41a is activated, and the inside of the chamber 10 is further decompressed and exhausted. As the pressure is reduced and exhausted, the solvent collection unit 50 is further cooled by the gas cooled by the adiabatic expansion mentioned above, and the pressure in the chamber 10 at that time becomes below the dew point (for example, 8 to 15° C.).

In addition, when the internal pressure of the chamber 10 is lower than the vapor pressure of the solvent on the substrate G due to depressurized exhaust, the vaporization of the solvent on the substrate G is accelerated. The vaporized solvent is collected and adsorbed in the solvent collection part 50 which is cooled as described above. By collecting in this way, the concentration of the gaseous solvent in the chamber 10 is maintained low. Therefore, the solvent on the substrate G can be quickly removed.

In addition, the solvent on the substrate G vaporized in this process is adsorbed not only on the solvent collection part 50 but also on the chamber 10 (specifically, the inner wall surface of the chamber 10 and the protective nets 33 and 43).

(S2: Drying process (drying process) of the solvent collection part 50 and the chamber 10) After the removal of the solvent on the substrate G is completed, the temperature of the solvent collection part 50 is raised, and the solvent collection part 50 is dried, and at the same time, the chamber 10 is dried. That is, after the removal of the solvent on the substrate G is completed, the temperature of the solvent collection part 50 is raised, and the solvent adsorbed on the solvent collection part 50 is detached from the solvent collection part 50 , and at the same time, the solvent adsorbed on the chamber 10 is desorbed from the solvent collection part 50 . Chamber 10 disengages.

This process is performed, for example, by continuing to exhaust gas through the dry pump 31a and exhaust gas through the turbomolecular pump 41a while moving the solvent collecting part 50 to the second position close to the top plate 12. By continuing such exhaust, for example, as shown in FIG. 6 , the pressure in the T1 chamber 10 first decreases when the drying of the solvent collection part 50 is completed, and the pressure in the T2 chamber 10 decreases when the drying of the chamber 10 is completed. . Therefore, for example, when the pressure in the chamber 10 reaches a preset pressure when drying of the chamber 10 is completed, the drying process of step S2 ends.

The drying process in step S2 is different from the above example. Even if the solvent collecting part 50 is not subjected to the radiation rate increasing process, the solvent collecting part 50 still receives the radiant heat from the top plate 12 and the radiant heat from the substrate G. Gradually heats up due to radiant heat. Among them, the solvent collecting part 50 is subjected to a radiation rate increasing process to increase the temperature rise rate of the solvent collecting part 50 through which radiant heat and the like from the top plate 12 are transmitted. Therefore, the time required for removing the solvent from the solvent collection unit 50 can be shortened, and the time required for the drying process in step S2 can be shortened.

(Step S3: Standby procedure) Until the purification process of the next step S4 is started, the reduced pressure drying device 1 is put into a standby state. During this process, the exhaust gas passing through the dry pump 31a and the exhaust gas passing through the turbomolecular pump 41a are still continued. In addition, during this process, the temperature of the solvent collection part 50 also gradually increases. In addition, this procedure can also be omitted.

(Step S4: Atmospheric opening procedure) When the standby program ends, the depressurized state in the chamber 10 is released, specifically, the chamber 10 is returned to atmospheric pressure.

More specifically, for example, the exhaust gas passing through the dry pump 31a and the exhaust gas passing through the turbomolecular pump 41a are stopped, and at the same time, atmospheric gas is introduced into the chamber 10, that is, the chamber 10 is purified, such as As shown in Figure 6, the chamber 10 is returned to atmospheric pressure. During the return to atmospheric pressure in the chamber 10 , the gas in the chamber 10 is heated due to adiabatic compression. The heated gas causes the solvent trap 50 to rise in temperature to a temperature higher than when the reduced pressure drying process starts (specifically When starting to depressurize the chamber 10) high temperature.

(Step S5: Cooling of the solvent collection part 50) Thereafter, the solvent trap 50 is cooled to the temperature at which the reduced pressure drying process is started. Specifically, for example, the solvent collection unit 50 is naturally cooled.

(Step S6: Unloading and unloading the substrate G) After the solvent collection unit 50 is cooled, the substrate G is unloaded from the chamber 10 and the next substrate G is loaded in at the same time. Specifically, when the solvent collecting part 50 is located in the second position described above, the carry-out inlet 11 a is opened, and the lifter (not shown) provided for the stage 20 passes from the stage 20 to the stage 20 . The dried substrate G is transferred to the external transport device. Next, the substrate G is transported out of the chamber 10 via the above-mentioned transport device. Thereafter, the next substrate G is transported into the chamber 10 through the above-mentioned transport device. Next, the next substrate G is transferred from the above-mentioned transport device to the stage 20 through the lifter, and is placed on the stage 20 . Then, the solvent collecting unit 50 is lowered to the first position described above, and the carry-out entrance 11a is brought into a closed state.

Accordingly, the reduced pressure drying process using the reduced pressure drying device 1 is completed for one substrate G, and then the next substrate G is subjected to the reduced pressure drying process as described above.

In addition, the cooling of the solvent collection part 50 in step S5 and the unloading and unloading of the substrate G in step S6 may be performed in parallel.

In addition, the reason why the solvent collection part 50 is cooled in step S5 is as follows. When the temperature of the solvent collection unit 50 is high when the reduced pressure drying process for the next substrate G is started (specifically, when the pressure reduction in the chamber 10 is started), the substrate drying process of step S1 for the next substrate G is , the temperature of the solvent collecting part 50 cannot be lowered sufficiently, and the solution on the substrate G cannot be dried quickly.

As described above, in the first mode, the solvent collection unit 50 is subjected to the radiation rate increasing process. For this reason, in the drying process of step S2 after the substrate drying process of step S1, the temperature of the solvent collection part 50 can be raised in advance, so that the solvent adsorbed on the solvent collection part 50 in the substrate drying process of step S1 can be quickly separated from the solvent collection part 50 . Therefore, the time required for the drying process in step S2 can be shortened. Accordingly, in the reduced pressure drying process, the time required for the process including the drying process of step S2 and subsequent to the substrate drying process of step S1 (that is, the post-processing process) can be shortened, and the entire reduced pressure drying process can be shortened. required time. In other words, in the first mode, the radiation rate of the solvent collecting part 50 is increased, thereby shortening the time until the vacuum drying process for the next substrate G is started, that is, the time of the post-processing process.

In addition, when manufacturing the solvent collecting part 50, the processing for increasing the radiation rate can be performed uniformly on the entire solvent collecting part 50, or when the solvent collecting part 50 is divided into a plurality of regions in a plan view, The degree of processing varies from region to region. For example, in the solvent collection unit 50 , the area that is most cooled by the adiabatic expanded gas that passes through the chamber 10 is the central area in a plan view. Therefore, the transmitted radiation rate of the central area can be improved. The degree of processing is larger than that of other areas.

[Modification of the first method] 7 is a cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to a modification of the first aspect. As for the material of the solvent collecting part 50, conductive materials such as stainless steel are basically used. In this way, when the solvent collecting part 50 is formed of a conductive material, as shown in FIG. 7, the energizing part 70 which energizes the solvent collecting part 50 and heats the solvent collecting part 50 may be provided. The energizing part 70 has, for example, a power supply 71 that supplies power to the solvent collection part 50 and a wiring 72 that connects the power supply 71 and the solvent collection part 50 .

By arranging the energizing part 70 in this way, the solvent collecting part 50 is energized in the drying process of step S2, so that the temperature rise rate of the solvent collecting part 50 in the drying process can be further increased, thereby promoting the removal of solvent from the solvent collecting part 50. of detachment. Therefore, the time required for the drying process in step S2 can be further shortened.

8 is a longitudinal cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to another modification of the first aspect. As shown in FIG. 8 , a heat medium pipe 80 serving as a heat medium flow path may be provided in the chamber 10 . The heat medium pipe 80 is provided between the solvent collection part 50 and the top plate 12, more specifically, between the solvent collection part 50 which becomes the 2nd position, and the top plate 12. In addition, the heat medium pipe 80 covers substantially the entire solvent collection part 50 in a plan view. Furthermore, a high-temperature heat medium supplied from a cooler unit (not shown) provided outside the chamber 10 flows through the heat medium pipe 80 .

By arranging such a heat medium pipe 80, high-temperature heat medium flows into the heat medium pipe 80 in the drying process of step S2, so that the temperature rise rate of the solvent collection part 50 in the drying process can be further increased, thereby promoting the removal of solvent from the solvent collection unit 50. The solvent is desorbed from the collecting portion 50 . Therefore, the time required for the drying process in step S2 can be further shortened.

9 is a longitudinal cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to another modification of the first aspect. As shown in FIG. 9 , an infrared light source 90 as an infrared irradiation unit that irradiates the solvent collection unit 50 with infrared rays to heat the solvent collection unit 50 may be provided. The infrared light source 90 is, for example, a halogen lamp. For example, the infrared light source 90 is provided on the side of the solvent collection part 50, and the optical axis of the infrared light source 90 is set horizontally. In addition, the infrared light source 90 is provided, for example, on both the positive side in the X direction and the negative side in the X direction. In addition, a plurality of infrared light sources 90 may be provided along the Y direction toward both the positive side in the X direction and the negative side in the X direction.

Such an infrared light source 90 is provided, and infrared light is irradiated from the infrared light source 90 to the solvent collection part 50 in the drying process of step S2, so that the temperature rise rate of the solvent collection part 50 in the drying process can be further increased, thereby promoting the removal of the solvent. The solvent is desorbed from the collection unit 50 . Therefore, the time required for the drying process in step S2 can be further shortened.

In the drying process of step S2, as described above, the temperature of the solvent collecting part 50 is increased due to the radiant heat from the top plate 12. Therefore, in order to further increase the temperature rise rate of the solvent collection part 50 in the drying process of step S2, at least the inner wall surface of the top plate 12 may be blackened. The blackening process of the top plate 12 is an anodizing process, for example, when aluminum is used as the material of the top plate 12 .

In addition, in the above example, the position of the solvent collecting part 50 in the drying process of step S2 is the second position. As mentioned above, the second position is the position when the substrate G is transferred between the stage 20 and the external transport device, and may not be the optimal position for increasing the temperature of the solvent collection unit 50 . In this case, the position of the solvent collecting part 50 in the drying process of step S2 may be, for example, a position closer to the top plate 12 than the second position. Accordingly, it is possible to further promote the temperature rise of the solvent collecting portion 50 through which the radiant heat from the top plate 12 has been transmitted.

[Second way] ＜Pressure reduction drying device＞ FIG. 10 is a longitudinal cross-sectional view illustrating the schematic structure of the reduced pressure drying device of the second embodiment. In the reduced pressure drying device of the second aspect, the solvent collection unit 50 may or may not be subjected to the radiation rate increasing process as in the first aspect, and may also be provided with at least any one of the configurations of the modifications of the first aspect. By.

As described above, in the vacuum drying process using the vacuum drying device 1 of the first aspect, the solvent vaporized from the substrate G is adsorbed not only on the solvent collecting part 50 but also on the inner wall surface of the chamber 10 , protection network 33, 43. In particular, the protective net 33 of the dry pump 31a has a large amount of thermally expanded gas passing through it when the chamber 10 is decompressed, so it is lower in temperature than other parts, so the amount of solvent adsorbed is also large. In addition, the protective net 33 is made of stainless steel, a material with relatively high thermal conductivity, and is difficult to heat up.

Therefore, the reduced pressure drying device 1a of FIG. 10 is different from the reduced pressure drying device of the first aspect in that it has a function of promoting the detachment of the solvent from the protective net. Specifically, it has a protective net that promotes the detachment of the solvent from the dry pump 31a. The detachment-promoting function.

In the example of Fig. 10, in the reduced pressure drying device 1a, the protective net 100 for the dry pump 31a is made of a material with a higher thermal conductivity than stainless steel, thereby having the above-mentioned promotion function. Materials with higher thermal conductivity than stainless steel are, for example, aluminum, copper, silver, etc.

＜Reduced pressure drying＞ The reduced pressure drying process using the reduced pressure drying device 1a of Figure 10 is the same as the reduced pressure drying process using the reduced pressure drying device 1 shown in Figures 1 to 3, and includes the aforementioned steps S1 to S6.

As described above, in the second aspect, the reduced pressure drying device 1 a has an acceleration function for promoting the detachment of the solvent from the protective net 100 . For this reason, in the drying process of step S2, the solvent can be quickly removed from the protective net 33. Therefore, the time required for the drying process in step S2 can be shortened. Accordingly, the time required for the post-processing process including the drying process of step S2 in the reduced pressure drying process can be shortened, and the time required for the entire reduced pressure drying process can be shortened. In other words, in the second mode, the detachment of the solvent from the protective net 33 is promoted to shorten the time until the vacuum drying process for the next substrate G is started, that is, the time of the post-processing process is shortened.

[Modification of the second method] FIG. 11 is a partially enlarged plan view of a protective net provided in a reduced pressure drying device according to a modification of the second aspect. As will be described below, the reduced pressure drying device of the second aspect may also be provided with a heating part that heats the protective net of the dry pump 31a to provide an acceleration function of promoting detachment from the protective net. The heating of the protective net thus promotes the above-mentioned detachment.

The protective net 110 of the dry pump 31a shown in FIG. 11 serves as a heating portion that serves to promote the detachment of the solvent from the protective net 110, and a heat medium flow path 110a is formed in the protective net 110. The protective net 110 is provided with through holes 110 b for allowing the gas exhausted from the chamber 10 to pass in a grid pattern. The heat medium flow path 110a has a shape corresponding to the arrangement state of the through-hole 110b in a plan view.

In this way, the heat medium flow path 110a is provided in the protection net 110. In the drying process of step S2, the high-temperature heat medium flows into the heat medium flow path 110a, which also allows the solvent to be removed from the protection net 110 during the drying process. of removal.

FIG. 12 is a partially enlarged cross-sectional view for explaining another example of the heating portion that serves to promote the detachment of the solvent from the protective net. In the example of FIG. 12 , a direct heating unit 120 is provided on the protective mesh 33 and directly heats the protective mesh 33 as a heating unit that promotes the desorption of the solvent from the protective mesh 33 of the dry pump 31 a. The direct heating part 120 is a mesh-shaped member like the protective net 33, for example, and a resistance heating wire (not shown) is provided in the interior thereof, and is connected to the protective net 33 in the exhaust port 13a.

By arranging the direct heating part 120 in this way, in the drying process of step S2, the protection net 33 is heated by the direct heating part 120, so that the solvent can be quickly removed from the protective net 33 in the drying process.

FIG. 13 is a partially enlarged cross-sectional view for explaining another example of the heating portion that serves to promote the detachment of the solvent from the protective net.

In the example of FIG. 13 , an exhaust mechanism 31 for depressurizing the chamber 10 is connected to the exhaust port 13 a via an exhaust pipe 131 . The exhaust port 13a, the exhaust mechanism 31 (specifically, the portion of the exhaust mechanism 31 that connects the exhaust pipe 131 and the dry pump 31a), and the exhaust pipe 131 constitute the exhaust line 130. The exhaust line 130 is connected to the dry pump 31 a and exhausts the chamber 10 .

The exhaust line 130 is provided with a protective net 132 similar to the aforementioned protective net 33. Among them, the protection net 132 is different from the protection net 33 and is provided in the exhaust pipe 131. In the example of FIG. 13 , the heating unit 133 that serves to promote the desorption of the solvent from the protective net 132 is provided outside the exhaust pipe 131 . The heating part 133 heats the protection net 132 by heating the exhaust pipe 131 . The heating unit 133 is, for example, a resistance heater.

By arranging the heating part 133 in this way, in the drying process of step S2, the protective net 132 is heated by the heating part 133, so that the solvent from the protective net 132 in the drying process can be quickly removed.

In addition, regarding the protective net of the turbomolecular pump 41a, the exhaust gas that passes through the turbomolecular pump 41a is started after the exhaust gas that passes through the dry pump 31a, so the amount of gas that is thermally expanded and cooled is passed through, There is less protection net 33 than for dry pump 31a. For this reason, the protective net for the turbomolecular pump 41a does not become colder and absorbs less solvent than the protective net for the dry pump 31a. Therefore, the reduced pressure drying device of the second aspect does not have the function of accelerating the detachment of the solvent from the protective net for the turbomolecular pump 41a. Among them, it may also have an acceleration function to promote the detachment of the solvent from the protective net for the turbomolecular pump 41a.

In the above example, although the exhaust line for the dry pump 31a and the exhaust line for the turbomolecular pump 41a are separately provided, the dry pump 31a and the turbomolecular pump 41a can also be connected in series. The exhaust lines can be set as common.

[3rd way] ＜Pressure reduction drying device＞ Fig. 14 is a longitudinal sectional view illustrating the schematic structure of a reduced pressure drying device according to a third aspect. In the reduced pressure drying device of the third aspect, the solvent collection unit 50 may or may not be subjected to the radiation rate increasing process as in the first aspect, and may also be provided with at least any one of the configurations of the modifications of the first aspect. By. Furthermore, the reduced pressure drying device of the third aspect may also have an acceleration function for accelerating the detachment of the solvent from the protective net for the dry pump 31a, just like the second aspect.

As mentioned above, in the reduced pressure drying process using the reduced pressure drying device 1 of the first aspect, when the reduced pressure state in the chamber 10 is released (specifically, the inside of the chamber 10 is returned to atmospheric pressure), due to adiabatic compression The gas in the chamber 10 is heated, and the heated gas causes the solvent trap 50 to become higher in temperature than when the reduced pressure drying process is started.

Therefore, the reduced pressure drying device 1b of FIG. 14 is different from the reduced pressure drying device of the first embodiment in that it is provided with a cooling unit that cools the solvent collecting unit 50 that is heated when the reduced pressure state in the chamber 10 is released.

In the example of FIG. 14 , the reduced pressure drying device 1 b is provided with a gas injection unit 200 that injects cooling gas for cooling the solvent collection unit 50 as the cooling unit. The gas injection unit 200 injects cooling gas toward the solvent collection unit 50 from above the solvent collection unit 50 , for example. The gas injection unit 200 has a pipe 201 extending in the X direction, for example. The piping 201 is provided between the solvent collection part 50 and the top plate 12 in the chamber 10, more specifically, between the solvent collection part 50 which becomes the 2nd position, and the top plate 12. In addition, the piping 201 has an injection port (not shown) in the lower part for injecting cooling gas downward. For example, a plurality of pipes 201 are provided along the Y direction. Accordingly, the entire solvent collection unit 50 can be cooled. The gas injection unit 200 injects the cooling gas supplied from a cooling gas source provided outside the chamber 10 toward the solvent collection unit 50 through an injection port (not shown) of the pipe 201 . The cooling gas is an inert gas such as _N gas.

＜Reduced pressure drying＞ The reduced pressure drying process using the reduced pressure drying device 1b of Figure 14 is basically the same as the reduced pressure drying process using the reduced pressure drying device 1 shown in Figures 1 to 3, including the aforementioned steps S1 to step S5. The specific contents of the cooling program of the solvent collection unit 50 in step S6 are different. In the reduced pressure drying process using the reduced pressure drying device 1 shown in FIGS. 1 to 3 , the solvent collecting part 50 is radiated and cooled in the procedure of step S6 . On the other hand, in the reduced pressure drying process using the reduced pressure drying device 1b of FIG. 14, the solvent collecting part 50 is actively cooled through the gas injection part 200.

As described above, in the third aspect, the reduced pressure drying device 1 b includes a cooling unit for cooling the solvent collecting unit 50 . To this end, in the cooling process of the solvent collecting part 50 in step S6, the solvent collecting part 50 can be rapidly cooled to the temperature when the reduced pressure drying process starts. Therefore, the time required for the cooling process of the solvent collection unit 50 in step S6 can be shortened. Accordingly, the time required for the post-processing process including the cooling process of the solvent collecting unit 50 in step S6 in the reduced pressure drying process can be shortened, and the time required for the entire reduced pressure drying process can be shortened. In other words, in the third mode, the solvent trap 50 that has been heated when the depressurized state in the chamber 10 is released is cooled, thereby shortening the time until the depressurized drying process for the next substrate G is started. Even the post-processing time is shortened.

[Modification of the gas injection unit] FIG. 15 is a cross-sectional view illustrating another example of the gas injection unit.

The gas injection part in the example of FIG. 15 injects the cooling gas while receiving the solvent collecting part 50 from the side of the solvent collecting part 50 . This gas injection part has a gas injection port 210 provided on the side of the solvent collection part 50 . The gas injection port 210 is provided in the side wall 11, for example. In addition, a plurality of gas injection ports 210 are provided along the Y direction, for example, on both the positive side in the X direction and the negative side in the X direction. The height position of the gas injection port 210 is the aforementioned second position. The gas injection port 210 injects the cooling gas supplied from the cooling gas source provided outside the chamber 10 toward the solvent collection unit 50 .

Using the cooling unit having such a gas injection port 210 , in the cooling process of the solvent trap 50 in step S6 , the solvent trap 50 may be rapidly cooled to the temperature at which the reduced pressure drying process starts.

FIG. 16 is a cross-sectional view illustrating another example of the cooling unit for cooling the solvent collection unit 50 . In the example of FIG. 16 , an air blower 220 for blowing air into the chamber 10 is provided as a cooling unit for cooling the solvent collection unit 50 .

The air blower 220 has a fan filter unit (FFU) 221 and a piping 222 . The air blower 220 is connected to the side opposite to the carry-out entrance 11a of the side wall 11, for example. An opening 11 b is provided on the side opposite to the carry-out entrance 11 a of the side wall 11 (the positive side in the X direction of the figure), that is, in a portion facing the carry-out entrance 11 a of the side wall 11 . The opening 11b is provided at a height position corresponding to the second position. FFU 221 is connected to this opening 11 b via pipe 222 . The air blower 220 uses the FFU 221 to blow air in the direction of the carry-out entrance 11a through the opening 11b to cool the solvent collection unit 50. In other words, the air blower 220 sends the clean gas from the FFU 221 into the chamber 10 through the opening 11 b, and cools the solvent collection part 50 at the second position through the sent clean gas. In addition, the air blower 220 transmits the clean gas from the FFU 221 to form a laminar flow along the solvent collection portion 50 in the chamber 10 .

In addition, the opening 11b is openable and closable through the gate valve 230. The FFU 221 and the gate valve 230 are controlled by the control unit U.

The air blower 220 is used after opening the opening 11b of the chamber 10 in the cooling process of the solvent collection unit 50 in step S6. In addition, the air blower 220 is used after opening the carry-out inlet 11a of the chamber 10 in the cooling process of the solvent collecting part 50 in step S6.

Using the air blowing unit 220 as described above, in the cooling process of the solvent collecting unit 50 in step S6 , the solvent collecting unit 50 may be quickly cooled to the temperature at which the reduced pressure drying process starts.

In addition, the air blower 220 is used to cool the solvent collection unit 50 by laminar flow along the solvent collection unit 50 , thereby preventing unnecessary parts (such as the stage 20 and the like) from being cooled. Furthermore, when cooling the solvent collection part 50 by the air blowing from the air blowing part 220, the carry-out inlet 11a of the chamber 10 is opened, and the solvent collecting part is cooled by the gas blown from the air blowing part 220 toward the carrying-out inlet 11a. 50, so that the gas from the air blower 220 is smoothly discharged from the chamber 10 through the carry-out inlet 11a. Therefore, the gas from the air blower 220 can pass through, thereby suppressing particles from flying in the chamber 10 .

The manner of this disclosure should be considered in all respects as illustrative and not restrictive. The above-described embodiments may be omitted, replaced, or modified in various ways without departing from the scope of the patent application and its spirit.

1b: Reduced pressure drying device 10: Chamber 20: Carrier platform 200:Gas injection part 210:Gas injection port 220: Air supply part G: Substrate

[Fig. 1] is a cross-sectional view schematically illustrating the inside of the reduced pressure drying device of the first embodiment. [Fig. 2] is a cross-sectional view along line A-A in Fig. 1. [Fig. 3] is a cross-sectional view taken along line B-B in Fig. 1. [Fig. 4] is a partially enlarged plan view of the solvent collection section. [Fig. 5] A flow chart illustrating an example of a reduced pressure drying process using the reduced pressure drying device of Fig. 1. [Fig. [Fig. 6] A diagram illustrating the temporal change of the pressure in the chamber when the radiation rate increasing process is not performed on the solvent collection part of the reduced pressure drying device of Fig. 1. [Fig. [Fig. 7] is a cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to a modification of the first aspect. [Fig. 8] is a longitudinal cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to another modification of the first aspect. [Fig. 9] is a longitudinal cross-sectional view illustrating the schematic structure of a reduced pressure drying device according to another modification of the first aspect. [Fig. 10] is a longitudinal sectional view illustrating the schematic structure of the reduced pressure drying device of the second embodiment. [Fig. 11] Fig. 11 is a partially enlarged plan view of a protective net provided in a reduced pressure drying device according to a modified example of the second aspect. [Fig. 12] Fig. 12 is a partially enlarged cross-sectional view for illustrating another example of the heating portion that serves to promote the detachment of the solvent from the protective net. [Fig. 13] Fig. 13 is a partially enlarged cross-sectional view for illustrating another example of the heating portion that serves to promote the detachment of the solvent from the protective net. [Fig. 14] is a longitudinal sectional view illustrating the schematic structure of a reduced pressure drying device according to a third aspect. [Fig. 15] Fig. 15 is a cross-sectional view illustrating another example of the gas injection unit. [Fig. 16] Fig. 16 is a cross-sectional view illustrating another example of the cooling unit that cools the solvent collection unit.

1b: Reduced pressure drying device

10: Chamber

11:Side wall

11a: Moving out entrance

12:Top plate

13b:Exhaust port

14: Gate valve

20: Carrier platform

40:Exhaust line

41:Exhaust mechanism

41a: Turbomolecular pump

42:Exhaust pipe

43:Protection net

50: Solvent collection department

60:Supporting components

200:Gas injection part

201:Piping

G: Substrate

Claims (16)

A reduced pressure drying device that dries the solution on the substrate under reduced pressure and has: a processing container, which is configured to be depressurized and accommodates the aforementioned substrate; A stage, which is provided in the aforementioned processing container and on which the aforementioned substrate is placed; a solvent collection unit that collects the solvent that is vaporized from the substrate during the reduced-pressure drying process and released into the solution in the processing container; and A cooling unit cools the solvent collecting unit that has been heated when the depressurized state in the processing container is released. The reduced pressure drying device according to claim 1, wherein the cooling unit has a gas injection unit that injects cooling gas for cooling the solvent collection unit. The reduced pressure drying device of claim 2, wherein the gas injection unit injects the cooling gas from above the solvent collection unit toward the solvent collection unit. The reduced pressure drying device of claim 2 or 3, wherein the gas injection part injects the cooling gas from a side of the solvent collection part toward the solvent collection part. The vacuum drying device of claim 4, wherein, The solvent collecting part is provided at a first height position when collecting the solvent, and is provided at a second height position higher than the first height position when cooling through the gas injection part, The gas injection port of the gas injection part is provided on the side of the solvent collection part and at a height corresponding to the second height position. The reduced pressure drying device according to any one of claims 1 to 3, wherein the cooling part has an air blowing part for blowing air into the processing container. The reduced pressure drying device according to claim 6, wherein the air blowing part forms a laminar flow along the solvent collecting part in the processing container. The vacuum drying device of claim 6, wherein, The processing container has a substrate unloading entrance, The air blowing part is provided on the opposite side to the carry-out entrance of the processing container, and blows air in the direction of the carry-out entrance. The reduced pressure drying device according to any one of claims 1 to 3, wherein the solvent collecting part is subjected to processing for increasing the radiation rate of the solvent collecting part. For example, the vacuum drying device of any one of claims 1 to 3 further has: An exhaust line, which is connected to an exhaust device to exhaust the aforementioned processing container; A protective net that prevents objects from entering the aforementioned exhaust device through the aforementioned exhaust line; and The accelerating function is to promote the detachment of the solvent that is vaporized from the substrate and adsorbed to the protective net along with the reduced pressure drying process from the protective net. A reduced pressure drying treatment method that uses a reduced pressure drying device to dry the solution on the substrate under reduced pressure. The aforementioned reduced pressure drying device is equipped with: a processing container, which is configured to be depressurized and accommodates the aforementioned substrate; A stage, which is provided in the aforementioned processing container and on which the aforementioned substrate is placed; Solvent capture section; and A cooling part that cools the aforementioned solvent collection part; The aforementioned vacuum drying treatment methods include: The pressure inside the processing container is reduced, and the gas in the processing container is cooled through adiabatic expansion. The cooled gas is passed through to cool the solvent collection part, and the cooled solvent collection part is passed through. A process in which the substrate placed on the stage is vaporized and released into the solution in the processing container, and the solvent in the solution is temporarily captured; The process of removing the captured solvent from the solvent collection part; After the above-mentioned disengagement procedure, the procedure for releasing the depressurized state in the above-mentioned processing container; and A process for cooling the solvent collecting section whose temperature has been raised in the process of releasing the reduced pressure state with the cooling section. Such as the vacuum drying method of claim 11, wherein, The solvent collecting part is processed to increase the radiation rate of the solvent collecting part, In the above-mentioned detachment process, the temperature of the solvent collecting part is raised, thereby collecting the trapped solvent from the solvent collecting part. Such as the reduced pressure drying method of claim 11 or 12, wherein, The aforementioned reduced pressure drying device is equipped with: An exhaust line, which is connected to an exhaust device to exhaust the aforementioned processing container; A protective net that prevents objects from entering the aforementioned exhaust device through the aforementioned exhaust line; and A heating part that heats the aforementioned protective net; The aforementioned reduced pressure drying treatment method includes: after the aforementioned temporary capturing procedure, a procedure of desorbing the solvent adsorbed on the aforementioned protective net during the aforementioned temporary capturing procedure; In the step of desorbing the solvent adsorbed on the protective net, the protective net is heated by the heating unit to promote the desorption of the solvent from the protective net. A method in which a solvent collecting unit collects a solvent in a solution on a substrate that is vaporized from the substrate during a drying process under reduced pressure, and the solvent is heated when the depressurized state in a processing container housing the substrate is released. The solvent collecting section is cooled to shorten the time until the vacuum drying process for the next substrate is started. The method according to claim 14, wherein the radiation rate of the solvent collection portion is increased to further shorten the time until the next substrate is started to undergo the reduced pressure drying process. The method of claim 14 or 15, wherein the solvent in the solution that is vaporized from the substrate during the reduced pressure drying process and is adsorbed on the substrate for protecting a protective net of an exhaust device provided in the exhaust line is promoted. The time from separation from the protective net to the start of the reduced pressure drying process for the next substrate is shortened.

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