KR100816707B1 - Reduced-pressure drying method, method of manufacturing functional film, method of manufacturing electro-optic device, electro-optic device, liquid crystal display device, organic el display device, and electronic apparatus - Google Patents

Abstract

In the drying process, the present invention can optimize the evaporation rate of the solvent of the applied liquid according to the type of liquid, and the vapor pressure distribution of the solvent is approximately uniform in the coated surface. Decompression drying method which can perform pressure reduction drying in the state, the manufacturing method of the functional film using this pressure reduction drying method, and the manufacturing method of an electro-optical device, an electro-optical device, a liquid crystal display device, an organic electroluminescence display, and an electronic device The task is to provide.

As a means of solving the said subject, the pressure reduction drying process of this invention makes a 1st chamber and 2nd chambers communicate with the base material in which the liquid body was apply | coated to the 1st chamber, and predetermined | prescribed operating pressure (Ps) The pressure reduction step of depressurizing by the pressure-reducing means, and the leaving step of closing the first chamber at a step of reaching a predetermined operating pressure Ps, leaving the first chamber to rise to a predetermined pressure by evaporation of the solvent. And a communication step of communicating the first chamber and the second chamber, which have risen at a predetermined pressure, and a discharge step of discharging vapor of the solvent diffused into the first chamber and the second chamber by the decompression means.

Vacuum pump, vacuum drying apparatus, liquid crystal display device, alignment film, organic EL display device

Description

REDUCED-PRESSURE DRYING METHOD, METHOD OF MANUFACTURING FUNCTIONAL FILM, METHOD OF MANUFACTURING ELECTRO- OPTIC DEVICE, ELECTRO-OPTIC DEVICE, LIQUID CRYSTAL DISPLAY DEVICE, ORGANIC EL DISPLAY DEVICE, AND ELECTRONIC APPARATUS}

1 is a schematic view showing the structure of a vacuum drying apparatus.

2 is a block diagram showing an electrical or mechanical configuration of a vacuum drying apparatus.

3 is a flow chart showing a vacuum drying method of Example 1. FIG.

4 is a graph of a reduced pressure drying profile of the reduced pressure drying apparatus corresponding to the flow chart of FIG. 3.

5 is a graph showing the amount of evaporation under reduced pressure of a multi-component liquid.

6 is a flow chart showing a vacuum drying method of Example 2. FIG.

7 is a graph of a reduced pressure drying profile of the reduced pressure drying apparatus corresponding to the flow chart of FIG. 6.

8 is a flowchart illustrating a vacuum drying method of Example 3. FIG.

9 is a graph of a reduced pressure drying profile of the reduced pressure drying apparatus corresponding to the flow chart of FIG. 8.

10 is a schematic cross-sectional view showing a main portion structure of a liquid crystal display device.

11 is a schematic cross-sectional view showing a main portion structure of an organic EL display device.

12 is a schematic perspective view of a portable information processing device;

Explanation of symbols for the main parts of the drawings

One… First chamber

2… Second chamber

6... Vacuum pump as decompression means

10... Vacuum drying equipment

50... Liquid crystal display

61, 71... CF substrate and counter substrate as a pair of substrates

63, 115... Upper banks as partition walls

64... Color layer as a color element

66, 68... electrode

67, 69... Alignment film

70... LCD

100... Organic EL display

101, 119... Substrate as a Pair of Substrate and Sealing Substrate

117R, 117G, 117B... Light emitting layer

200... Portable information processing device as an electronic device

L… Liquid

Ps… Operating pressure

W… Substrate as a substrate

The present invention is a reduced pressure drying method of drying a substrate coated with a liquid under reduced pressure and forming a film on the surface of the substrate, a manufacturing method of a functional film and a manufacturing method of an electro-optical device, an electro-optical device, a liquid crystal display device, An organic EL display device and an electronic device.

Pressure reduction drying apparatus which evaporates and dries the solvent (solvent) component contained in a liquid body under reduced pressure, when forming a film by apply | coating the liquid body containing a film formation material to the surface of wafer-like board | substrates (base materials), such as a semiconductor. A reduced pressure drying method using is known. For example, Patent Literature 1 discloses an airtight container for placing a substrate coated with a coating liquid (photoresist) under a reduced pressure atmosphere, reduced pressure evacuation means for evacuating the inside of the airtight container under reduced pressure, and a substrate to be opposed to the substrate in the airtight container. A reduced pressure drying apparatus has been proposed in which a rectifying plate having a size equal to or larger than the effective area is arranged.

Moreover, as a pressure reduction drying method using said pressure reduction drying apparatus, the process of placing a rectifying plate so that it may oppose through the clearance gap with the surface of the board | substrate mounted in the board | substrate mounting part provided in the inside of an airtight container, and apply | coated the inside of an airtight container Pressure reduction drying method provided with the process of depressurizingly evacuating to the pressure which a solvent component evaporates violently from a liquid, and changing the exhaust flow volume setting value over at least 2 steps, while a solvent component evaporates violently from a coating liquid. Is proposed.

In such a reduced pressure drying method, a step of evaporating the solvent at a high speed and a step of evaporating the solvent at a slow speed are performed by changing the exhaust flow rate setting value while the solvent component in the coating liquid is vigorously evaporating. The cross-sectional shape of the coating film at the edge portion is corrected. This makes it possible to easily set the exhaust flow rate pattern that enables flattening of the coating film and uniformity in the surface.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2004-47797

Thus, in the manufacturing process of many electronic devices including semiconductors, a liquid body containing various film-forming materials (functional materials) is applied to a substrate such as a wafer, and a coating film (functional film) made of the film-forming material is applied. It takes a process that tries to form on the surface.

However, in the drying process which dries a liquid body and forms a coating film, drying so that the coating film after formation is flatter and the film thickness distribution may become uniform even in the surface of a base material can use very much the said reduced pressure drying apparatus and the reduced pressure drying method. It is difficult. Because of the various liquids used, the saturated vapor pressure, rheology properties (such as viscosity, elasticity, plasticity, thixotropy, and the like) change for each material. In addition, the behavior of the liquid body such as the evaporation rate during the drying process is also changed by the volume and surface area ratio of the solute and the solvent contained in the liquid body.

Therefore, even if the rate at which the solvent evaporates from the liquid under reduced pressure is controlled by changing the exhaust flow rate setting using the conventional vacuum drying method described above, the flow (convection) of the liquid occurs during the drying process and the film thickness is caused by the surface tension. There is a problem that the uniformity of is lowered. In addition, even if the direction in which the vapor of the solvent is discharged by the rectifying plate is controlled, a difference occurs in the distribution of vapor concentration (or vapor pressure) at the center portion and the edge portion of the substrate. The problem is that in-plane distribution occurs.

The present invention has been made in consideration of the above problems, and in the drying process, it is possible to optimize the evaporation rate of the solvent of the liquid applied according to the type of liquid, and the vapor pressure distribution of the solvent is approximately uniform in the surface coated. Providing the vacuum drying method which can perform vacuum drying in a state, the manufacturing method of a functional film using this vacuum drying method, the manufacturing method of an electro-optical device, an electro-optical device, a liquid crystal display device, an organic electroluminescence display, and an electronic device The purpose.

In the vacuum drying method of the present invention, a solvent of a liquid applied to a substrate is evaporated under reduced pressure using a vacuum drying apparatus having a second chamber that can be decompressed by a decompression means and a first chamber that can communicate with the second chamber. A pressure reduction drying method in which the first chamber and the second chamber communicate with each other in a state in which a substrate is accommodated in the first chamber, and a pressure reduction step of depressurizing the pressure by means of a pressure reduction means to a predetermined operating pressure and a step of reaching a predetermined operating pressure. The first chamber is sealed, and the leaving process is allowed to stand until the solvent evaporates and the first chamber rises to a predetermined pressure, a communication step of communicating the first chamber and the second chamber raised to the predetermined pressure, and the first And a discharge step of discharging the vapor of the solvent diffused into the chamber and the second chamber by the decompression means.

The behavior of the liquid under reduced pressure is affected by the vapor pressure, evaporation rate, and the like, which vary depending on the type of solute or solvent constituting the liquid, the compounding state. According to this method, in the depressurization process, the base material coated with the liquid body is accommodated in the first chamber and decompressed to a predetermined operating pressure. Thereafter, in the leaving process, evaporation of the solvent of the liquid body proceeds in the state where the first chamber is closed, and the pressure is left until the pressure of the first chamber reaches a predetermined pressure. In the communicating step, the first chamber and the second chamber, which have risen to a predetermined pressure, communicate with each other, and the vapor of the solvent diffused into the first chamber and the second chamber is discharged by the decompression means in the discharging step. Therefore, since the evaporation of the solvent of the liquid body proceeds in the closed first chamber under the predetermined operating pressure, it is not affected by the exhaust by the decompression means and at a predetermined evaporation rate corresponding to the predetermined operating pressure. The liquid can be dried in a substantially uniform state within the surface on which the distribution of the vapor pressure of the solvent is applied until the pressure is reached. In addition, since the first chamber and the second chamber are in communication when the solvent evaporates and the pressure of the first chamber reaches a predetermined pressure, that is, a pressure higher than the predetermined operating pressure, the vapor of the solvent in the first chamber is controlled. It is easily diffused to the two chamber side, and can be discharged by the decompression means. That is, if the predetermined operating pressure and the predetermined pressure of the first chamber are set according to the type of liquid to be dried, the evaporation rate of the solvent of the applied liquid can be optimized without being affected by the exhaust by the decompression means. It is possible to provide a reduced pressure drying method capable of performing reduced pressure drying in a substantially uniform state within the surface to which the vapor pressure distribution of the solvent is applied.

Further, the predetermined operating pressure is preferably a pressure higher than the vapor pressure of the solvent of the liquid body. Under reduced pressure, the solvent of the liquid body starts to evaporate by the kinetic energy of the solvent molecules even if the degree of reduced pressure does not reach the vapor pressure of the solvent. When the reduced pressure approaches the vapor pressure of the solvent, evaporation occurs violently, and in some cases dolby. According to this, since the predetermined | prescribed operating pressure in a decompression process is a pressure higher than the vapor pressure of the solvent of a liquid body, abrupt evaporation of a solvent can be avoided and generation of a dolby can be reduced. Therefore, it can reduce that the film shape after drying becomes unstable by Dolby. Moreover, since dolby arises in the unspecified place of the base material with which the liquid body was apply | coated, it can also reduce that the variation of the in-plane film thickness becomes large by this. That is, the pressure reduction drying method which can dry a liquid body under reduced pressure in the state in which the film shape after drying is flat and there is little in-plane film thickness variation can be provided.

The predetermined pressure is a pressure obtained by adding a predetermined operating pressure to a vapor pressure when a predetermined amount of solvent has evaporated in the sealed first chamber, and it is preferable to exhaust the gas under a pressure higher than the predetermined pressure in the discharging step.

According to this method, a predetermined pressure is made into the pressure which added the predetermined | prescribed operating pressure to the vapor pressure in the case where a fixed amount of solvent evaporated in the sealed 1st chamber, and exhausts under pressure higher than a predetermined pressure in a discharge process. Therefore, in the discharging step, since the exhaust is performed under a pressure higher than the predetermined pressure, it is possible to suppress the evaporation of the solvent more than a predetermined amount evaporated in the leaving process. Therefore, it becomes possible to manage the amount of the solvent evaporated in the leaving process, and it is possible to estimate the ratio of the solute and the solvent in the vacuum drying process. Therefore, if the amount of the solvent to be evaporated in advance is appropriately set, the pressure is reduced under more optimized conditions. Drying can be performed. In addition, the fixed amount of the solvent in this case may be the whole quantity of the solvent contained according to the kind of liquid body, and may be set as the quantity which divided | divided the whole quantity suitably.

Moreover, it is preferable to dry the liquid body apply | coated to the base material by repeating a discharge process from the said pressure reduction process. According to this, since the discharge process is repeatedly performed from the depressurization process, the solvent is evaporated step by step according to the amount of the liquid applied to the substrate, the film shape after drying is more flat, and the film thickness variation in the film is less. It is possible to provide a reduced pressure drying method capable of drying the liquid under reduced pressure in a state.

Moreover, another pressure reduction drying method of this invention uses the pressure reduction drying apparatus which has a 1st chamber which can communicate with a 2nd chamber which can be decompressed by a decompression means, and a 2nd chamber, The solvent of the liquid body apply | coated to a base material under reduced pressure A reduced pressure drying method for evaporating to dry, wherein the first chamber and the second chamber are in communication with each other in a state where the substrate is accommodated in the first chamber, and the solvent is evaporated from the liquid to increase the viscosity until immediately before the viscosity affecting the film shape. (Iii) the depressurization step of depressurizing to a predetermined operating pressure, and the first chamber is sealed at the step of reaching the predetermined operating pressure, and the solvent is left to evaporate until the first chamber rises to a predetermined pressure. A neglecting step to be performed; a communicating step of communicating the first chamber and the second chamber that have risen to a predetermined pressure; and vapor of the solvent diffused into the first chamber and the second chamber by the decompression means. It is characterized in that it comprises a discharge process.

According to this method, in the depressurization process, the first chamber and the second chamber are depressurized to a predetermined operating pressure which is increased until immediately before the viscosity of the solvent of the liquid body of the substrate contained in the first chamber to affect the film shape. Therefore, in the depressurization process, most solvents evaporate in a state of not affecting the shape of the membrane, thereby decreasing the solvent ratio to the solute. Thereafter, in the leaving process, the first chamber is sealed and the solvent of the liquid body evaporates, and the pressure of the first chamber is left until the predetermined pressure is reached while the viscosity of the liquid body is increased to a viscosity that affects the film shape. Therefore, the evaporation of the solvent proceeds only by the diffusion of the vapor in the closed first chamber. In a communication process, the 1st chamber and the 2nd chamber which rose to predetermined | prescribed pressure are communicated, and the vapor | steam of the solvent spread | diffused to the 1st chamber and the 2nd chamber in the discharge process is discharged | emitted by a pressure reduction means. Therefore, in the leaving process, it is possible to provide a reduced pressure drying method capable of performing reduced pressure drying at a slow evaporation rate of the solvent so as not to be affected by the exhaust by the decompression means and not affect the shape of the liquid body.

The predetermined pressure may be a pressure obtained by adding a predetermined operating pressure to the substantially saturated evaporation pressure of the solvent of the liquid body in the first chamber. According to this, in the leaving process, the base material on which the liquid body is applied is left until the solvent evaporates in the sealed first chamber and reaches a substantially saturated vapor pressure. Therefore, the solvent and the liquid body which have evaporated to the surface of the base material become substantially in an equilibrium state, and can be dried under reduced pressure in a state where the vapor pressure distribution is more uniform in the plane. In addition, as the equilibrium state approaches, the evaporation rate becomes very slow, so that the influence of the evaporation rate on the shape of the liquid body can be reduced.

In the reduced-pressure drying method of the above-described invention, in the communicating step, it is preferable to communicate the first chamber, which has risen to a predetermined pressure, to the second chamber having a larger volume than the first chamber. According to this, since the second chamber is larger than the volume of the hermetically sealed first chamber, the vapor of the solvent evaporated in the first chamber can be easily diffused to the second chamber side.

In the reduced pressure drying method of the above-described invention, it is preferable that the second chamber is depressurized to a pressure less than a predetermined operating pressure between the decompression step and the communication step. According to this, since the pressure of the 2nd chamber is reduced compared with the pressure of the 1st chamber before communication, when the 1st chamber and the 2nd chamber are communicated in a communication process, the vapor | steam of the solvent in a 1st chamber is more easily made 2nd. It can diffuse to the chamber side.

Moreover, another pressure reduction drying method of this invention uses the pressure reduction drying apparatus which has a 1st chamber which can communicate with a 2nd chamber which can be decompressed by a decompression means, and a 2nd chamber, The solvent of the liquid body apply | coated to a base material under reduced pressure A reduced pressure drying method for evaporating to dry, comprising: a decompression step of depressurizing a second chamber, which is in non-communication state with a first chamber, by a decompression means to a predetermined operating pressure in a state where a substrate is accommodated in a first chamber; A communication step of communicating the first chamber and the second chamber at a step of reaching a predetermined operating pressure, and a discharge step of discharging the vapor of the solvent diffused into the first chamber and the second chamber.

When the pressure of the solvent of the liquid is relatively high and most of the solvent is evaporated in the depressurization process at a predetermined operating pressure, it is difficult to dry it under reduced pressure at a ratio of solute and solvent in which the shape of the liquid is stably maintained. Lose. According to this method, in the communication step, since the first chamber and the second chamber communicate with each other when the second chamber reaches a predetermined operating pressure, the first chamber can be rapidly depressurized without undergoing an intermediate decompression process. . Therefore, the solvent can be evaporated quickly, and the shape change of the liquid body in the depressurization process can be suppressed and dried under reduced pressure.

Further, the predetermined operating pressure is preferably a pressure higher than the vapor pressure of the solvent of the liquid body. When the first chamber communicates with the second chamber decompressed at a predetermined operating pressure, if the first chamber is rapidly depressurized and the solvent evaporates rapidly from the liquid body, there is a fear that dolby may occur. According to this method, since the predetermined operating pressure is a pressure higher than the vapor pressure of the solvent of the liquid body, generation of such a dolby can be reduced. That is, it can reduce that the film shape after drying becomes nonuniform in surface by Dolby.

In the vacuum drying method of the above-described invention, in the discharge step, when the liquid is dried and the film is thickened to a degree that the film shape is fixed, it is preferable to perform positive exhaust gas to increase the exhaust speed of the pressure reducing means. According to this, when a liquid body has already thickened to such an extent that it is hard to be influenced by exhaust, even if it carries out positive exhaust which raises the exhaust velocity of a decompression means in an exhaust process, there is little possibility that a film shape may change. Therefore, by performing positive exhaust, drying of the liquid can be promptly promoted. That is, pressure reduction drying can be performed efficiently.

Moreover, in the vacuum drying method of this invention, it is preferable to introduce an inert gas from the outside into the first chamber so that the first chamber is not decompressed below a predetermined operating pressure in the discharge step. According to this, since inert gas is introduce | transduced from the exterior so that a 1st chamber may not depressurize below a predetermined | prescribed operating pressure in a discharge process, the surface of a liquid body will become more than a predetermined | prescribed operating pressure, and the evaporation of the solvent which remains in a liquid body will be prevented. It can be suppressed. Therefore, since the evaporation of the solvent is not promoted more than necessary in the discharging step of discharging the vapor of the solvent, it can be dried under reduced pressure while maintaining the ratio of the solute and the solvent to suppress the change in the shape of the liquid body.

Further, in the vacuum drying method of this invention, in the discharging step, after the vapor of the solvent of the first chamber is diffused into the second chamber and the first chamber is closed, the solvent diffused into the second chamber by the decompression means. The steam may be discharged. According to this, in the discharging step, since the vapor of the solvent evaporated in the first chamber is once diffused to the second chamber side and the first chamber is sealed, the airflow when discharging the vapor of the solvent diffused into the second chamber to the decompression means. Will not be affected. In other words, it is possible to reduce the variation of the vapor pressure distribution on the surface of the liquid body under the influence of the exhaust and to cause in-plane film thickness variation after drying.

The manufacturing method of the functional film of this invention is a manufacturing method of the functional film which apply | coats a liquid body containing a functional material to a base material, and makes it dry, and forms a functional film on the surface of a base material. It is characterized by drying.

According to this method, the liquid is dried using the vacuum drying method of the present invention, so that the solvent is evaporated from the liquid containing the functional material at an optimum evaporation rate, and the vapor pressure distribution in the plane becomes substantially uniform. It can be dried under reduced pressure. Therefore, after drying under reduced pressure, a functional film can be manufactured in a state where the shape is flat and the in-plane film thickness variation is small.

The manufacturing method of the electro-optical device of the present invention is a manufacturing method of the electro-optical device having a pair of substrates and a functional film constituting pixels on at least one substrate, and functions using the manufacturing method of the functional film of the present invention. It is characterized by forming a film.

According to this method, since a functional film is formed using the manufacturing method of the functional film of the said invention, after pressure reduction drying, the electro-optical device in which the functional film was formed in the state which is flat in shape and there is little in-plane film thickness variation can be manufactured. That is, the electro-optical device which has little variation in the electro-optical characteristics of the pixel determined by the functional film and has stable electro-optical characteristics can be manufactured.

The electro-optical device of the present invention is an electro-optical device having a pair of substrates and provided with a functional film constituting pixels on at least one substrate, wherein the functional film is formed using the manufacturing method of the electro-optical device of the present invention. It is done.

According to this structure, since a functional film is formed using the manufacturing method of the electro-optical device of the said invention, after the pressure reduction drying, the electro-optical device which has a functional film formed in the state in which the shape was flat and the in-plane film thickness variation was small is provided. can do. That is, the electro-optical device having little variation in the electro-optical characteristics of the pixel determined by the functional film and having stable electro-optic characteristics can be provided.

The liquid crystal display device of this invention is a liquid crystal display which has a pair of board | substrate which has an electrode, the alignment film as a functional film which covers an electrode in the range corresponding to a display area at least, and the liquid crystal inserted between a pair of board | substrates through an alignment film. As an apparatus, the orientation film was formed using the manufacturing method of the functional film of the said invention.

According to this structure, since the alignment film is formed using the manufacturing method of the functional film of the said invention, it can provide the liquid crystal display device which has an alignment film formed in the state which was flat in pressure reduction, and in-plane film thickness variation was small after drying under reduced pressure. have. That is, the liquid crystal display device which has little display of orientation nonuniformity and display nonuniformity by the film thickness variation of an oriented film, and is excellent in display quality can be provided.

Another liquid crystal display device of the present invention is a liquid crystal having a pair of substrates, a color element as a functional film partitioned by at least one substrate by partition walls, and a liquid crystal inserted between the pair of substrates. The display device is characterized in that a color element is formed using the method for producing a functional film of the present invention.

According to this structure, since a color element is formed using the manufacturing method of the functional film of the said invention, the liquid crystal display device which has a color element formed in the state which was flat in pressure reduction and the in-plane film thickness variation is small after drying under reduced pressure is provided. can do. That is, a liquid crystal display device with less display unevenness such as color unevenness due to film thickness unevenness of color elements and good display quality can be provided.

An organic EL display device of the present invention is an organic EL display device having a pair of substrates and a light emitting layer as a functional film partitioned by at least one substrate by partition walls, wherein the light emitting layer is formed using the method for producing a functional film of the present invention. Characterized in that formed.

According to this structure, since the light emitting layer is formed using the manufacturing method of the functional film of the said invention, it can provide the organic electroluminescence display which has a light emitting layer formed in the state which was flat in pressure reduction and the in-plane film thickness variation was small after drying under reduced pressure. Can be. That is, an organic EL display device with less display unevenness such as light emission unevenness or color unevenness due to film thickness unevenness of the light emitting layer and good display quality can be provided.

The electronic device of the present invention is equipped with any one of the electro-optical device, the liquid crystal display device, and the organic EL display device of the present invention.

According to this configuration, the electronic device of the present invention has an electro-optical device having a stable electro-optical characteristic with a flat shape of the functional film constituting the pixel and less in-plane film thickness variation, and an uneven alignment or display unevenness due to the film thickness variation of the alignment film. Liquid crystal display device with less display quality with less display unevenness such as color unevenness due to film thickness unevenness of color elements, and display unevenness such as light emission unevenness or color deformation due to film thickness unevenness with good display quality with less display unevenness Any one of these organic EL display devices with little display quality is mounted. Therefore, an electronic device capable of displaying information such as an image with good display quality can be provided.

An embodiment of the present invention is a solvent of a liquid body under reduced pressure using a chamber for accommodating a substrate to which a liquid body containing a functional material is applied, and a pressure reduction drying apparatus including at least pressure reduction means capable of depressurizing the inside of the chamber. It demonstrates based on the vacuum drying method which evaporates and dries.

(Decompression drying device)

First, a reduced pressure drying apparatus is demonstrated. 1 is a schematic view showing the structure of a vacuum drying apparatus. In detail, FIG. 1A is a schematic side cross-sectional view of the apparatus, and FIG. 1B is a schematic plan cross-sectional view of the apparatus. As shown in FIG. 1A, the vacuum drying apparatus 10 according to the present embodiment accommodates the substrate W on which the liquid body L is applied, in the chamber 3, and the solvent of the liquid body L is used. It is an apparatus for evaporating and drying under reduced pressure.

The chamber 3 has a first chamber 1 on the upper side and a second chamber 2 on the lower side in the drawing, so that the volume of the second chamber 2 becomes larger than that of the first chamber 1. The partition wall part 18 which partitions the inside of the chamber 3 is provided. The mounting table 11 on which the substrate W is mounted is provided on the side of the first chamber 1 of the partition wall 18. In addition, the mounting plate 11 is provided with a rectifying plate 15 disposed to face each other at a predetermined distance. The rectifying plate 15 is provided with a plurality of ventilation holes 15a through which gas is passed in a range corresponding to the region of the substrate W to be mounted.

The connection hole 17 is provided in the vicinity of the upper center of the first chamber 1, and one of the pipes 14 capable of introducing nitrogen (N ₂ ) gas, which is an inert gas, is connected to the first chamber 1. . The other side of the pipe 14 is connected to an N ₂ gas supply source (not shown) via the N ₂ valve 9. In addition, a vacuum gauge 4 capable of measuring the depressurization state in the first chamber 1 is provided in the side wall portion of the first chamber 1. The vacuum gauge 4 is electrically connected to the control part 20 (refer FIG. 2) mentioned later, and outputs a pressure value.

The connection hole 16 is provided in the center vicinity of the lower part (bottom surface) of the 2nd chamber 2, and one side of the piping 13 is connected. The other side of the piping 13 is connected to the vacuum pump 6 as a pressure reduction means capable of decompressing the second chamber 2 via the vacuum valve 7. The vacuum pump 6 uses a dry pump and a turbo molecular pump, for example. Moreover, you may use combining these pumps so that setting of the operating pressure which makes a target depressurization state possible. The side wall part of the 2nd chamber 2 is provided with the vacuum gauge 5 which can measure the pressure reduction state in the 2nd chamber 2. The vacuum gauge 5 and the vacuum pump 6 are also electrically connected to the control unit 20 (see FIG. 2), which will be described later, and the control unit 20 detects the output (pressure value) of the vacuum gauge 5, and the vacuum pump The exhaust velocity of (6) can be controlled.

As shown in (a) and (b) of FIG. 1, a communication port 19 through which the first chamber 1 and the second chamber 2 of the chamber 3 communicate with each other is mounted on the partition wall 18. It is provided in four places along the edge of (11). Four communication valves 8 in which the rotating shaft 8a is connected to the four motors 12 attached to the outer wall of the chamber 3 are respectively provided in the part in which the four communication ports 19 open. As the communication valve 8 drives the motor 12 and the rotary shaft 8a rotates, the valve 8b attached to the rotary shaft 8a opens and closes the communication port 19. When the communication valve 8 closes the communication port 19, the first chamber 1 and the second chamber 2 are sealed to each other. The four motors 12 are electrically connected to the control unit 20 (refer to FIG. 2), respectively, and the control unit 20 controls the open / closed state of the communication valve 8 by independently driving the four motors 12, respectively. do.

The pressure reduction drying apparatus 10 drives the vacuum pump 6 by opening the communication valve 8 in the state which closed the door (not shown) and sealed the inside of the chamber 3, and the 1st chamber 1 and the 2nd It is possible to depressurize the chamber 2.

2 is a block diagram showing the electrical or mechanical configuration of the vacuum drying apparatus. As shown in FIG. 2, the reduced pressure drying device 10 includes an operation unit 21 having a CPU, a timer 22 for measuring time, and a storage unit 23 in which data on reduced pressure drying conditions such as a reduced pressure drying profile is stored. It has the control part 20 provided. Two vacuum gauges 4 and 5 are electrically connected to the control unit 20 to detect the depressurized state of each of the first chamber 1 and the second chamber 2. Moreover, the vacuum pump 6 is electrically connected, and the drive, exhaust speed, etc. are controlled. Four motors 12 are electrically connected, and the opening / closing state of the communication valve 8 is controlled by controlling the drive of the motor 12. Vacuum valve 7 and the N ₂ valve 9, either the solenoid valve has been used, these are also electrically connected to the control unit 20 is controlled to open and close. In addition, an input unit 24 and a display unit 25 having a drive device or the like of a recording medium capable of exchanging data with a keyboard or a recording medium are electrically connected. From the input part 24, pressure reduction drying conditions, such as a pressure reduction drying profile, can be input and memorize | stored in the memory | storage part 23. FIG. The display unit 25 displays a variety of input data and the pressure values of the first chamber 1 and the second chamber 2 detected by the vacuum gauges 4 and 5 and the moving state of the reduced pressure drying device 10, for example. For example, the ON-OFF of the apparatus, the opening / closing of various valves, the elapsed time corresponding to the decompression drying step measured by the timer 22, etc. can be displayed. The calculating part 21 can calculate the evaporation amount of a solvent etc. based on the data contained in the pressure reduction drying profile etc. which were memorize | stored in the memory | storage part 23, and the output (pressure value) of the vacuum systems 4 and 5. Further, the number of times the reduced pressure drying operation included in the reduced pressure drying profile or the like is set can be read, and the reduced pressure drying operation can be performed.

(Example 1)

Next, the vacuum drying method of Example 1 which applied this invention is demonstrated based on FIG. 3 and FIG. 3 is a flowchart showing a vacuum drying method of Example 1. FIG. 4 is a graph of the vacuum drying profile of the vacuum drying apparatus. In detail, FIG. 4 is a graph which shows the pressure change of the 1st chamber 1 and the 2nd chamber 2 with respect to the time progress of the vacuum drying corresponding to the flowchart of FIG. The vertical axis of the graph is the logarithmic value of the pressure P. Moreover, the evaporation amount control type pressure reduction drying method of controlling the evaporation amount of the solvent which evaporates from the liquid L and drying under reduced pressure is shown.

(Decompression drying method of evaporation control type)

As shown in FIG. 3, in the vacuum drying method of Example 1, the substrate W, on which the liquid body L is applied, is accommodated in the first chamber 1, and the first chamber 1 and the second chamber ( In the state where 2) was communicated, the decompression process (step S1) which depressurizes the 1st chamber 1 and the 2nd chamber 2 to predetermined operation pressure Ps by the vacuum pump 6 is provided. In addition, in the step of reaching the predetermined operating pressure Ps, the first chamber 1 is sealed, and the leaving process is left until the solvent evaporates and the first chamber 1 rises to a predetermined pressure (step S3). ) And a communication step (step S5) for communicating the first chamber 1 and the second chamber 2 that have risen at a predetermined pressure. Moreover, the discharge process (step S6) which discharges the vapor | steam of the solvent spread | diffused in the 1st chamber 1 and the 2nd chamber 2 by the vacuum pump 6 is provided. Moreover, the process (step S7) of calculating the evaporation amount of the solvent evaporated in the sealed 1st chamber 1 and determining whether the evaporation of the solvent was complete | finished is provided.

Step S1 of FIG. 3 is a pressure reduction process. In step S1, the board | substrate W in which the liquid L was apply | coated was mounted in the mounting base 11 of the 1st chamber 1, a door is closed, and it accommodates in the chamber 3 in a substantially sealed state. The control unit 20 first confirms that the N ₂ valve 9 is closed. When the control unit 20 is closed, the control unit 20 drives the motor 12 to open the four communication valves 8, and the first communication chamber 19 opens the first chamber ( 1) and the 2nd chamber 2 are made into communication. Next, as shown in FIG. 4, the vacuum valve 7 is opened to drive the vacuum pump 6 to start depressurization (time t ₀ ), and the pressure P ₁ of the first chamber ₁ and the second chamber ( The pressure P _{2 of 2} ) is decompressed so as to reach a predetermined operating pressure Ps. The flow then advances to step S2.

Step S2 in Fig. 3 is a step of determining whether it has reached a pressure operating pressure (Ps) to (P _2), the target of pressure (P ₁₎ and second chamber (2) of the first chamber (1). And if it has not reached, the pressure reduction of step S1 is continued, and if it reaches, it progresses to step S3.

Step S3 is an leaving process. In step S3, the control unit 20 includes a first pressure chamber (1) (P ₁₎ and the pressure in the second chamber (2), (P ₂₎ is a time (t ₁₎ at the predetermined operating pressure (Ps) Then, the motor 12 is driven to close the four communication valves 8. Thereby, the communication port 19 is closed and the 1st chamber 1 in which the board | substrate W was accommodated is sealed. The pressure P1 of the sealed 1st chamber 1 rises from the operating pressure Ps as shown by the dashed line of the graph of FIG. 4, as the solvent of the liquid L advances. In addition, the control unit 20 closes the vacuum valve 7 when the second chamber 2 is depressurized to a target pressure lower than the operating pressure Ps. The flow then advances to step S4.

Step S4 of FIG. 3 is a step of determining whether the pressure P ₁ of the first chamber 1 has reached a predetermined pressure. In Step S4, as shown in FIG. 4, the control unit 20 detects the value of the pressure P ₁ by the vacuum gauge 4. Thereby, the pressure difference (DELTA) P with the operating pressure Ps is calculated | required. Since the pressure difference ΔP depends on the amount of evaporation of the solvent (the oblique portion in the drawing), the volume V of the closed first chamber 1 is assumed to be an ideal gas when the solvent vapor evaporated under a constant temperature. Is confirmed, and the evaporation amount (molecular weight n) can be obtained by substituting the gas state equation (PV = nRT). Since the quantity of the liquid body apply | coated to the board | substrate W, and the content rate of a solvent are known values, the amount of evaporation of the solvent required in order to dry the apply | coated liquid body can be calculated | required. Therefore, how much solvent is evaporated from the liquid L in the sealed first chamber 1 by at least one reduced-pressure drying operation, or when ΔP corresponding to the evaporation amount of a predetermined amount of solvent is set in advance, the evaporation amount Can be controlled to dry under reduced pressure. In addition, although the predetermined amount of the solvent in this case was made into the fixed amount which divided | segmented the whole quantity of the solvent contained in the liquid L by the decompression | suction recovery, you may change suitably in the repeating step of reduced pressure drying.

The calculation method for calculating the amount of evaporation is input from the input unit 24 as a program in advance and stored in the storage unit 23. The calculating part 21 executes the program memorize | stored in the memory | storage part 23, and displays the evaporation amount of the solvent corresponding to (D) on the display part 25. As shown in FIG. The control unit 20 compares the pressure P ₁ of the first chamber 1 detected by the vacuum gauge 4 with a predetermined pressure Ps + ΔP and determines it. If the predetermined pressure is reached, the process proceeds to step S5. If no, it proceeds to step 7.

Step S5 of FIG. 3 is a communication process. In step S5, the control unit 20 detects the output of the vacuum gauge 4, and when the pressure P ₁ (or pressure difference ΔP) reaches a predetermined pressure, that is, the evaporation amount reaches a predetermined value. At the time t ₂ , the motor 12 is driven to open the communication valve 8. As a result, the first chamber 1 and the second chamber 2 communicate with each other. The flow then advances to step S6.

Step S6 is a discharge process. In step S6, the control unit 20 does not lower the pressure P ₁ than the operating pressure Ps when the second chamber 2 having a lower pressure than the operating pressure Ps communicates with the first chamber 1. N ₂ gas is introduced into the first chamber 1 by opening the N ₂ valve 9. The introduced N ₂ gas passes through the vent hole 15a provided in the rectifying plate 15 and flows from the top of the substrate W toward the communication port 19. As a result, it leads the vapor of the solvent evaporated from the liquid material (L) toward the second chamber (2) with a stream of N ₂ gas. In addition, the introduction of N ₂ gas prevents the pressure P ₁ from being higher than the operating pressure Ps and the evaporation of a new solvent from the liquid L. That is, evaporation of the solvent is suppressed, the vapor pressure distribution is maintained at a substantially constant state on the surface of the liquid body L of the substrate W, and the evaporated solvent can be discharged. At this time, the control unit 20 opens the vacuum valve 7 and drives the vacuum pump 6 to exhaust the gas so as to reduce the exhaust speed in response to the flow rate of the N ₂ gas. If the first chamber 1 and the second chamber 2 are not in communication and the N ₂ gas is not introduced, the pressure P ₁ becomes less than or equal to the operating pressure Ps, resulting in excessive solvent evaporation or dolby, so N ₂ Introduce gas.

In addition, it is not necessary to introduce N ₂ gas as an inert gas as a method of discharging the vapor of the solvent. In the chamber 3 of the present embodiment, the volume of the second chamber 2 is set to be larger than that of the first chamber 1. In the closed first chamber 1, the solvent evaporates from the liquid L, and the pressure P ₁ becomes higher than the pressure P ₂ of the second chamber 2. As long as the pressure P1 is not lower than the operating pressure Ps when the first chamber 1 and the second chamber 2 are in communication, the solvent evaporated to the second chamber 2 having a large volume and a small pressure. The vapor can be diffused and discharged. Further, when the vapor of the solvent diffuses to the second chamber 2 side and the pressure P ₁ = pressure P ₂ , the first chamber 1 may be sealed and then evacuated. In this way, the influence of the exhaust by the vacuum pump 6 can be reduced, the evaporation of the solvent of the liquid L can be suppressed, and the vapor pressure distribution can be maintained in a more uniform state.

Next, the control unit 20 closes the N ₂ valve 9 at a time t ₃ in which the N ₂ gas is introduced to increase the pressure in the chamber 3. Then, the flow returns to step S1 to increase the evacuation speed of the vacuum pump 6 so that the inside of the chamber 3 in which the first chamber 1 and the second chamber 2 communicate is at a predetermined operating pressure Ps. Depressurize. Thereafter, similarly to the operation described above, the communication valve 8 is closed at the time t ₄ at which the operating pressure Ps is reached to close the first chamber 1, and the pressure P ₁ (or the pressure difference ΔP) is closed. At a time t ₅ )) reaches a predetermined pressure, a reduced pressure drying operation is performed in which N ₂ gas is introduced to discharge vapor of the evaporated solvent. Therefore, the control unit 20 carries out repeatedly until the first cycle to the reduced pressure drying operation between the time (t ₀₎ ~ time (t _3), the evaporation of the solvent in the liquid material (L) ends. As evaporation of the solvent proceeds, of course, the time until the pressure P ₁ of the closed first chamber ₁ reaches a predetermined pressure Ps + ΔP becomes long. Therefore, when the pressure P ₁ of the 1st chamber 1 in step S4 does not reach predetermined | prescribed pressure even after the leaving time limit time set by the leaving process (step S3), it progresses to step S7.

Step S7 of FIG. 3 is a process of determining whether evaporation of a solvent was complete | finished. In step S7, the control unit 20 integrates the amount of evaporated solvent evaporated by repetition of the vacuum drying operation. In the storage unit 23, the solvent amount M is stored as data from the composition of the liquid body L. The control unit 20 compares the accumulated evaporation amount N of the solvent and the solvent amount M stored in the storage unit 23 to determine whether or not the evaporation of the solvent has ended. In this case, it is necessary to consider the amount of evaporation of the solvent until the operating pressure Ps is reached. Therefore, when integrated evaporation amount N becomes 95% or more with respect to solvent amount M, evaporation is complete | finished and it progresses to step 8. If it is determined that it is not finished, evaporation is promoted by continuing the leaving process of step S3. In addition, as a method for determining whether or not the evaporation of the solvent has ended, the discharge of the vacuum pump 6 is stopped once by looking at the time in the discharging step, and the amount of evaporation from the pressure detected by the vacuum systems 4 and 5 at the time of stopping. May be obtained and determined based on this amount of evaporation.

Step S8 of FIG. 3 is a process of atmospherically opening the chamber 3. In step S8, the control unit 20 stops the driving of the vacuum pump 6, opens an atmospheric opening valve (not shown) of the vacuum pump 6, introduces external air, and introduces the first chamber 1. The second chamber 2 in communication with) is returned to atmospheric pressure. This completes the series of reduced pressure drying operations.

It is considered that the evaporation rate of the solvent is lowered by the fact that the time required for the first chamber 1 sealed to reach the predetermined pressure Ps + ΔP is increased by repeating the reduced pressure drying operation from step S1 to step S6. In order to evaporate a solvent more reliably, you may change the value of operation pressure Ps in the repeated pressure reduction drying operation process. In the decompression drying operation performed repeatedly, when the first chamber 1 is sealed in a state in which the operating pressure Ps is lowered than the previous time or in a stepwise manner, the evaporation rate of the solvent can be suppressed from being lowered. In other words, it is possible to accelerate the evaporation by increasing the constant rate or the evaporation rate almost at a constant rate. Alternatively, when the first chamber 1 is sealed in a state in which the operating pressure Ps is increased in step or from the previous time, the later evaporation rate can be lowered as compared with the evaporation rate in the preceding decompression drying operation. That is, it becomes possible to promote evaporation by controlling the evaporation rate. Thus, for example, if the accumulated evaporation amount N of the solvent calculated by the calculation unit 21 is 90% or more and less than 95% of the solvent amount M, the operating pressure Ps is set to be 95% or more earlier than the previous time. You may change and set a reduced pressure drying profile so that it may lower and dry under reduced pressure.

In addition, the setting method of the value of (DELTA) P in a vacuum drying operation is as follows. The calculating part 21 can calculate the molecular weight n of the solvent evaporated from the value of (DELTA) P. Knowing the molecular weight (n) of the evaporated solvent, it is possible to calculate the molecular weight of the solvent remaining in the liquid (L), thereby analyzing how the ratio of the solute and the solvent of the liquid (L) changes due to reduced pressure drying. Can be. The rheological properties of the liquid L described above also vary depending on the ratio of the solute and the solvent. Therefore, since the change in the shape of the liquid L in the drying process is actively suppressed and dried, an experiment of changing the value of ΔP to dry under reduced pressure is carried out in advance, and when the film shape after the experiment drying is observed, the cross-sectional shape is flat. And it becomes possible to set the predetermined value of (DELTA) P by which the in-plane film thickness variation becomes small according to the cycle of pressure reduction drying operation.

Next, the predetermined operating pressure Ps will be described. Even if the components of the solvent are single, evaporation of the solvent starts even if the liquid L under reduced pressure does not reach the vapor pressure (20 ° C) of the solvent. If the liquid L is multi-component, it is expected that the reduced pressure value at which evaporation of the solvent starts depends on the type of solvent and the mixing ratio. 5 is a graph showing the amount of evaporation under reduced pressure of a multi-component liquid body. In detail, the liquid L used when forming the alignment films 67 and 69 (refer to FIG. 10) of the liquid crystal display panel 60 mentioned later is a plural-system liquid whose vapor pressure (20 degreeC) is 60 Pa. In the upper body L, the evaporation amount NL under reduced pressure is calculated | required. As a method of investigating the change in the reduced pressure value or the amount of evaporation at which evaporation starts, a measuring device (for example, an electronic balance, etc.) capable of measuring the mass of the liquid L is installed in the chamber 3, and an appropriate amount of liquid Weigh (L). Then, when the vacuum pump 6 is driven to depressurize the inside of the chamber 3 at a substantially constant speed, the mass (evaporation amount) of the pressure P detected by the vacuum gauge 5 and the liquid L detected by the metering device. ) Can be explained. If the pressure P is near the vapor pressure of a solvent, a solvent may evaporate violently and may rush. If it is Dolby, the shape of the liquid L will be largely disturbed, and the film | membrane of the cross-sectional shape after drying cannot be obtained. In addition, since the dolby occurs at an unspecified place on the surface of the substrate W on which the liquid L is applied, the film thickness in the plane also differs. In order to avoid such a defect, in the reduced pressure drying method of the liquid body L containing the alignment film forming material, the predetermined operating pressure Ps for bringing the first chamber 1 and the second chamber 2 into a predetermined reduced pressure state. Is a value higher than the vapor pressure of the solvent and is set to 200 kPa which is slightly lower than the value at which the solvent starts to evaporate. In addition, the unit NL is a normal litter.

The effect of the said Example 1 is as follows.

(1) In the pressure reduction drying method of the first embodiment, in the depressurization step (step S1), the control unit 20 opens the communication valve 8 to communicate the first chamber 1 and the second chamber 2. The vacuum pump 6 is driven to depressurize the first chamber 1 in which the substrate W on which the liquid body L is applied is accommodated to a predetermined operating pressure Ps. Thereafter, in the leaving process (step S3), the control unit 20 closes the communication valve 8 to close the first chamber 1, and the evaporation of the solvent of the liquid L proceeds. Then, it is left until the pressure of the first chamber 1 reaches a predetermined pressure Ps + ΔP. In the communication step (step S5), the control unit 20 opens the communication valve 8 to communicate the first chamber 1 and the second chamber 2 raised to a predetermined pressure. In the discharging step (step S6), the control unit 20 controls the evacuation speed of the vacuum pump 6 and discharges the vapor of the solvent diffused into the first chamber 1 and the second chamber 2. Therefore, since the evaporation of the solvent of the liquid L proceeds in the closed first chamber 1 under the predetermined operating pressure Ps, it is not affected by the exhaust by the vacuum pump 6, The liquid L can be dried at an evaporation rate corresponding to the operating pressure Ps and in a substantially uniform state within the surface to which the vapor pressure distribution of the solvent is applied until a predetermined pressure is reached. In addition, since the first chamber 1 and the second chamber 2 communicate with each other when the solvent evaporates and the pressure of the first chamber 1 reaches a predetermined pressure, that is, a pressure higher than the predetermined operating pressure Ps. The vapor of the solvent in the first chamber 1 can be diffused to the side of the second chamber 2 having a low pressure and large in volume, and discharged by the vacuum pump 6. That is, if the predetermined operating pressure Ps of the first chamber 1 and the predetermined pressure are set according to the type of the liquid L for drying, the evaporation rate of the solvent of the applied liquid L can be optimized. Thus, a reduced pressure drying method capable of carrying out reduced pressure drying in a substantially uniform state within the surface to which the distribution of the vapor pressure of the solvent is applied can be provided.

(2) In the reduced pressure drying method of the first embodiment, the control unit 20 repeatedly performs the reduced pressure drying operation from the reduced pressure step (step S1) to the discharge step (step S6). Therefore, the solvent can be evaporated step by step according to the application amount (solvent amount) of the liquid L, so that the method of drying the liquid L can be provided under reduced pressure, which is more flat and can form a film with less variation in in-plane film thickness. .

(3) In the vacuum drying method of Example 1, the predetermined operating pressure Ps is higher than the vapor pressure of the liquid L (20 ° C) and slightly lower than the value at which the solvent starts to evaporate. It is set. Therefore, it is possible to reduce defects such that the solvent evaporates rapidly, the shape of the liquid body L is greatly disturbed, and the cross-sectional shape of the film after drying is not flat. In addition, defects such as the in-plane vapor pressure distribution fluctuate due to rapid evaporation of the solvent and the in-plane film thickness after drying can be reduced.

(4) In the vacuum drying method of the first embodiment, in the discharging step, the control unit 20 opens the N ₂ valve 9 so that the first chamber 1 is not decompressed below a predetermined operating pressure Ps. N ₂ gas is introduced into the first chamber 1 from the outside. As a result, the N ₂ gas in which the vapor of the solvent diffused into the first chamber 1 is introduced into the second chamber 2 is discharged by the vacuum pump 6 and the surface of the liquid L is formed. It becomes more than this operating pressure Ps, and the evaporation of the solvent which remains in the liquid L can be suppressed. Therefore, in the discharging step of discharging the vapor of the solvent, since the evaporation of the solvent is not promoted more than necessary, the amount of evaporation of the solvent corresponding to the predetermined pressure (Ps + ΔP) can be suppressed in the set state. That is, it can be made to dry under reduced pressure, controlling the ratio of a solute and a solvent and suppressing the shape change of the liquid L. FIG. In addition, if the air is dried while being actively evacuated, the vapor pressure distribution on the substrate W may fluctuate, which may cause in-plane variation in the shape of the liquid L after drying. In the discharging step of the above embodiment, since the evaporation from the liquid L is suppressed or stopped when the evaporated solvent is evacuated, it is possible to provide a vacuum drying method capable of forming a stable film having a small in-plane variation. .

(Example 2)

Next, the vacuum drying method of Example 2 is demonstrated based on FIG. 6 and FIG. FIG. 6 is a flowchart showing a vacuum drying method of Example 2. FIG. 7 is a graph of the reduced pressure drying profile of the reduced pressure drying apparatus. In detail, FIG. 7 is a graph which shows the pressure change of the 1st chamber 1 and the 2nd chamber 2 with respect to the lapse of time of pressure reduction drying corresponding to the flowchart of FIG. The vertical axis of the graph is the logarithmic value of the pressure P. Moreover, the pressure reduction drying method of the shape control type which controls the shape of liquid L and carries out reduced pressure drying is shown.

(Pressure reduction drying method of shape control type)

As shown in FIG. 6, in the vacuum drying method of Example 2, the substrate W on which the liquid body L is applied is accommodated in the first chamber 1, and the first chamber 1 and the second chamber ( In the state where 2) is in communication, the vacuum chamber 6 increases the viscosity of the first chamber 1 and the second chamber 2 until just before the viscosity of the solvent evaporating from the liquid L to affect the film shape. The pressure reduction process (step S11) which pressure-reduces to the predetermined | prescribed operation pressure Ps to make is provided. In addition, in the step in which the predetermined operating pressure Ps is reached, the first chamber 1 is sealed, and the leaving process is left until the solvent evaporates and the first chamber 1 rises to a predetermined pressure (step S13). And determining whether or not the pressure P ₁ has reached a predetermined pressure in the sealed first chamber 1 (step S14). Moreover, the communication process (step S15) which connects the 1st chamber 1 and the 2nd chamber 2 which rose to the predetermined pressure, and the vapor | steam of the solvent spread | diffused in the 1st chamber 1 and the 2nd chamber 2, The discharge process (step S16) which discharges | discharges with the vacuum pump 6 is provided. The predetermined pressure in the present embodiment is set to the pressure obtained by adding the operating pressure Ps to the saturated vapor pressure Psa of the solvent of the sealed first chamber 1.

Step S11 of FIG. 6 is a pressure reduction process. In step S11, the board | substrate W in which the liquid L was apply | coated was mounted in the mounting base 11 of the 1st chamber 1, a door is closed, and it accommodates in the chamber 3 in a substantially sealed state. The control unit 20 checks whether the N ₂ valve 9 is closed, and if closed, drives the motor 12 to open the four communication valves 8, and the first opening 1 is opened by the communication port 19. And the second chamber 2 are in communication. Next, as shown in FIG. 7, the vacuum valve 7 is opened to drive the vacuum pump 6 to start depressurization (time t ₀ ), and the pressure P ₁ of the first chamber ₁ and the second chamber. The pressure P _{2 in} ( ₂ ) is depressurized so as to reach a predetermined operating pressure Ps. The flow then advances to step S12.

Step S12 of FIG. 6 is a step of determining whether it has reached a pressure operating pressure (Ps) to (P _2), the target of pressure (P ₁₎ and second chamber (2) of the first chamber (1). In step S12, the setting of the operating pressure Ps is set to the value which the liquid phase L thickens from the liquid phase L to just before the viscosity which most solvent evaporates and affects a film shape. The control unit 20 detects the output from the vacuum gauges 4 and 5 and determines whether at least the first chamber 1 has reached the operating pressure Ps. And if it determines that it has not reached, it continues with depressurization of step S11, and when it determines with reaching, it progresses to step S13.

Step S13 of FIG. 6 is an leaving process. In step S13, the control unit 20, the pressure in the first chamber (1) (P ₁₎ and the second pressure chamber (2), (P ₂₎ it is reaching the predetermined operating pressure (Ps) the time (t ₁ ), The motor 12 is driven to close the four communication valves 8. Thereby, the communication port 19 is closed and the 1st chamber 1 in which the board | substrate W was accommodated is sealed. The pressure P ₁ of the hermetically sealed first chamber 1 is in a state in which the liquid L is thickened until just before the viscosity affecting the film shape by evaporation of the solvent of the liquid L. As shown by the broken line in the graph of 7, the pressure rises from the operating pressure Ps. That is, drying under reduced pressure in the range of the viscosity (ratio of solute and solvent) which determines a film shape advances at the evaporation rate of a very slow solvent. In addition, the control unit 20 closes the vacuum valve 7 when the second chamber 2 is depressurized to a target pressure lower than the operating pressure Ps. The flow then advances to step S14.

Step S14 of FIG. 6 is a step of determining whether the pressure P ₁ of the first chamber 1 has reached a predetermined pressure. In Step S14, as shown in FIG. 7, the control unit 20 detects the value of the pressure P ₁ by the vacuum gauge 4. By leaving the first chamber 1 in a sealed state, evaporation of the solvent proceeds and the pressure P ₁ rises, but then the liquid phase L and the evaporated solvent vapor are in equilibrium, and the rise stops and stabilizes. . Thereby, the operating pressure Ps and the pressure difference (DELTA) P are calculated | required. In this case, it is determined that the evaporation of the solvent of the liquid L reaches a saturation state in the sealed first chamber 1. The saturated vapor pressure Psa of the solvent can be obtained by calculation because the volume of the first chamber 1 is a known value. In this case, the control unit 20 sets the predetermined pressure as the operating pressure Ps + saturation vapor pressure Psa, and determines whether or not the predetermined pressure is reached by comparing with the stabilized pressure P ₁ . When it is determined that the predetermined pressure has been reached, the process proceeds to step S15. If it is determined that it has not been reached, the process proceeds to step S13 to maintain the first chamber 1 in a sealed state. In this case, the pressure P ₁ does not have to be strictly the value of the operating pressure Ps + the saturated vapor pressure Psa. If it is approximately saturated vapor pressure, it is judged to be in an equilibrium state. Moreover, you may compare (DELTA) P and saturated vapor pressure Psa.

From step S13 to step S14, since the first chamber 1 is left until it reaches a saturation state, the liquid L is subjected to very low pressure drying. That is, since the ratio of the solute to the solvent is slowly changed and dried in a state where the fluidity of the liquid L is suppressed, the cross-sectional shape of the film after drying is flat and the film can be formed in a state where the in-plane film thickness variation is smaller. .

Step S15 of FIG. 6 is a communication step. In step S15, the control unit 20 detects the output of the vacuum gauge 4 and, as shown in FIG. 7, operates the motor 12 at a time t _{2 when} the pressure P ₁ reaches a predetermined pressure. Drive to open the communication valve (8). The flow then advances to step S16.

Step S16 of FIG. 6 is a discharge process. In step S16, when the 2nd chamber 2 with a pressure lower than the operating pressure Ps communicates with the 1st chamber 1, the control part 20 transfers the vapor of the solvent in the 1st chamber 1 to 2nd. since the induction side of the chamber (2), by opening the N ₂ valve 9 is introduced into the N ₂ gas to the first chamber (1). The introduced N ₂ gas passes through the vent hole 15a provided in the rectifying plate 15 and flows from the upper portion of the substrate W toward the communication port 19. Therefore, the vapor of the solvent evaporated from the liquid L is discharged to the second chamber 2 side together with the airflow of N ₂ . At this time, the control unit 20 opens the vacuum valve 7 and controls and evacuates the vacuum pump 6 so that the exhaust speed is increased in response to the flow rate of the N ₂ gas. The liquid L is dried under reduced pressure at a very slow evaporation rate in the standing step of Step S13. At this point, the liquid L is thickened in a stable state (fixed state) without depending on the subsequent drying step. Therefore, since there, the active to be lower than the operating pressure (Ps) the pressure liquid body in the chamber 3 to take out the solvent remaining in (L) (P ₁₎ by performing the exhaust and dried. The exhaust velocity and the decompression time to be actively exhausted are inputted from the input unit 24 as data of the reduced pressure drying profile and stored in the storage unit 23. The control unit 20 detects the elapsed time measured by the timer 22 and drives the vacuum pump 6 based on the set exhaust speed and the decompression time. In this case, pressure P ₂ <pressure P ₁ , and the vapor of the solvent evaporated in the first chamber 1 is diffused to the second chamber 2 having a large volume without introducing N ₂ gas. It is possible to exhaust by making. The first chamber 1 may be sealed when the solvent vapor is diffused to the second chamber 2 side. According to this, when drying of the liquid L is still insufficient at this time and it repeats a reduced pressure drying operation, it is possible to avoid the influence by the evacuation of the vacuum pump 6. Further, as a method of determining whether or not positive exhaustion is to be completed, the exhaustion of the vacuum pump 6 is once stopped by looking at the time during the discharging step, and the amount of evaporation from the pressure detected by the vacuum systems 4 and 5 at the time of stopping. May be obtained and determined based on the amount of evaporation. The flow then advances to step S17.

Step S17 in Fig. 6 is a step of opening the chamber 3 to the atmosphere. In step S17, the control unit 20 closes the N ₂ valve 9 and stops driving the vacuum pump 6 at the time t ₃ when the positive exhaust is completed. Then, the open air valve (not shown) of the vacuum pump 6 is opened to introduce outside air, and the second chamber 2 communicated with the first chamber 1 is returned to atmospheric pressure (time t ₄ ). This completes the series of reduced pressure drying operations.

The amount of solvent M also varies depending on the type of liquid L and the amount applied. In addition, the volume of the 1st chamber 1 becomes a fixed value. Therefore, since the amount of evaporation of the solvent in the saturated state (corresponding to the oblique portion in the drawing) depends on the volume of the first chamber 1, the case where the drying of the liquid L is not always completed in one depressurization drying operation. I think. Therefore, you may set a pressure reduction drying profile so that a discharge process may be repeatedly performed from said pressure reduction process. In this case, it is preferable to exhaust the pressure setting in the chamber 3 in the discharging step with the pressure P ₁ as the pressure higher than the operating pressure Ps as in the first embodiment.

The effect of Example 2 is as follows.

(1) In the pressure reduction drying method of the second embodiment, in the depressurization step (step S11), the control unit 20 opens the communication valve 8 to communicate the first chamber 1 and the second chamber 2. Drive the vacuum pump 6, and the liquid body L until just before the viscosity at which the solvent evaporates and affects the film shape in the first chamber 1 containing the substrate W on which the liquid L is applied. The pressure is reduced to the operating pressure Ps which increases. Thereafter, in the leaving process (step S13), the control unit 20 closes the communication valve 8 to keep the first chamber 1 sealed, and the solvent of the liquid L proceeds to evaporate. Then, it is left until the pressure P ₁ of the first chamber 1 reaches a predetermined pressure (operating pressure Ps + saturated vapor pressure Psa). In the communication step (step S15), the control unit 20 opens the communication valve 8 to communicate the first chamber 1 and the second chamber 2 that have reached a predetermined pressure. In the discharging step (step S16), the control unit 20 opens the N ₂ valve 9 to introduce N ₂ gas to discharge the vapor of the solvent from the first chamber 1 to the second chamber 2. At the same time, the exhaust speed of the vacuum pump 6 is increased to positively evacuate, and the solvent remaining in the liquid L is evaporated and discharged. Therefore, it is possible to give an extremely slow dry state (evaporation rate) in which drying proceeds only by diffusion of steam until reaching the saturated vapor pressure Psa without being affected by the exhaust by the vacuum pump 6. In addition, drying advances in the state in which the vapor pressure distribution is uniform in plane in the sealed first chamber 1, and the in-plane uniformity of the film shape is improved. In addition, since the liquid L is thickened and left in a stable state, the film can be actively evacuated so as to take out the remaining solvent. That is, the pressure reduction drying method of controlling and drying the shape under reduced pressure of the liquid L can be provided.

(Example 3)

Next, the vacuum drying method of Example 3 is demonstrated based on FIG. 8 and FIG. 8 is a flowchart illustrating a vacuum drying method of Example 3. FIG. 9 is a graph of the reduced pressure drying profile of the reduced pressure drying apparatus. In detail, FIG. 9 is a graph which shows the pressure change of the 1st chamber 1 and the 2nd chamber 2 with respect to the time-lapse of the pressure reduction drying corresponding to the flowchart of FIG. Moreover, the rapid drying pressure reduction drying method is shown.

(Dry drying method of rapid drying)

As shown in FIG. 8, in the vacuum drying method of Example 3, the second chamber 2 in a non-communication state is operated at a predetermined operating pressure in a state where the substrate W is accommodated in the first chamber 1 in a substantially sealed state. The first chamber 1 and the second chamber (in the depressurization step (step S21) of depressurizing the vacuum pump 6 to Ps and the second chamber 2 attained a predetermined operating pressure Ps. A communication step (step S23) for communicating 2) and a discharge step (step S24) for discharging the vapor of the solvent diffused into the first chamber 1 and the second chamber 2 are provided.

Step S21 of FIG. 8 is a pressure reduction process. In step S21, the control unit 20 drives the motor 12 to close the communication valve 8, and seals the first chamber 1 in which the substrate W to which the liquid L is applied is accommodated. Then, the vacuum pump 6 is driven to depressurize the inside of the second chamber 2 such that the pressure P ₂ of the second chamber 2 becomes a predetermined operating pressure Ps. The predetermined operating pressure Ps in this embodiment is set to be higher than the vapor pressure of the solvent of the liquid body. The flow then advances to step S22.

Step S22 is a step of determining whether or not the pressure P ₂ of the second chamber 2 has reached the target operating pressure Ps. In step S22, the control unit 20 determines whether or not the pressure P ₂ of the second chamber 2 has reached the operating pressure Ps based on the detection signal input from the vacuum gauge 5. Then, if it is determined that it is not reached, the depressurization of step S21 is continued, and if it is determined that it is reached, the flow proceeds to step S23.

Step S23 is a communication process. In step S23, the second chamber (2) at a time (t ₁₎ reaches the operating pressure (Ps), the control unit 20 as shown in Figure 9 by driving the motor 12, the communication valve (8) The first chamber 1 and the second chamber 2 communicate with each other by opening. The pressure P ₁ of the first chamber 1 in communication with the second chamber 2 rapidly depressurizes toward the pressure P ₂ of the second chamber 2 from the state of approximately atmospheric pressure. That is, between time t ₁ and time t ₂ is a rapid depressurization process of the first chamber 1. The flow then advances to step S24.

Step S24 of FIG. 8 is a discharge process. In step S24, as shown in FIG. 9, between this time t ₁ and time t ₂ , the control part 20 continues to drive the vacuum pump 6, and the vapor | steam of the solvent which evaporates from the liquid L. FIG. (The evaporation amount corresponds to the slanted portion in the drawing). Subsequently, at time t ₂ , the N ₂ valve 9 is opened to introduce N ₂ gas into the first chamber 1 to discharge the vapor of the solvent. At this time, the exhaust velocity of the vacuum pump 6 is increased in accordance with the flow rate of the N ₂ gas so as to obtain an optimum pressure-drying profile, and the vacuum valve 7 and Opening and closing the N ₂ valve 9 gives a desired reduced pressure drying profile. For example, when the solvent evaporates and the pressure in the chamber 3 rises above the target pressure, the vacuum valve 7 is opened and exhausted. In addition, when the pressure in the chamber 3 falls below the target pressure because the evaporation amount of the solvent decreases, the vacuum valve 7 is closed, the N ₂ valve 9 is opened to introduce N ₂ gas to return to the target pressure. As shown in FIG. 9, the target pressure is preferably approximately equal to the operating pressure Ps. Thereby, the dolby of a solvent can be suppressed. That is, it becomes possible to reduce the in-plane deviation of the film shape due to Dolby. The flow then advances to step S25.

Step S25 of FIG. 8 is a step of determining whether or not the evaporation of the solvent is completed. In step S25, the pressure reduction drying profile is managed based on the data of the pressure and time in the chamber 3, for example, and the time point of the positive pressure reduction exhaust profile which predetermined time passed is the time point of evaporation of a solvent ended. Determine. In addition, for example, when the vacuum valve 7 is closed, the timing at which the increase in pressure is not detected by the vacuum gauges 4 and 5 is determined as the timing at which the evaporation of the solvent is completed. If it is determined that evaporation of the solvent has not been completed, the flow returns to step S24 to continue the discharging step. If it is determined that it has finished, the process proceeds to step S26. In addition, as a method for determining whether or not the evaporation of the solvent has ended, the exhaust by the vacuum pump 6 is once stopped by looking at the time during the discharging step, and the amount of evaporation from the pressure detected by the vacuum systems 4 and 5 at the time of stopping. May be obtained and determined based on this amount of evaporation.

Step S26 of FIG. 8 is a process of atmospherically opening the chamber 3. In step S26, it is determined the time (t ₃₎ that the evaporation is complete the solvent as shown in Fig. 9, the control unit 20 the air introducing valve at the same time to stop the driving of the vacuum pump (6) a vacuum pump (6) (Not shown) is opened to introduce outside air, and the second chamber 2 communicated with the first chamber 1 is returned to atmospheric pressure. This completes the series of reduced pressure drying operations.

Such a quick-drying vacuum drying method has a relatively high vapor pressure of the solvent and a reduced pressure until reaching the operating pressure Ps as compared with the liquid body L to which the vacuum drying methods of Examples 1 and 2 are applied. It is used in the case of considerable evaporation of the solvent in the process. The liquid L needs to control the depressurization process until the ratio of the solute and the solvent to fix the membrane shape is reached. Since the liquid L in the first chamber 1 is subjected to a reduced pressure which is reduced to a predetermined operating pressure Ps at once without undergoing a decompression process, a decompression process in which the ratio of the solute and the solvent is changed and a shape gradient is likely to occur Omitted and dried under reduced pressure in the range of the ratio of the solute and solvent in which the membrane shape stabilizes.

Moreover, in the above-mentioned pressure reduction drying method, it is preferable to set the volume of the 2nd chamber 2 of the pressure reduction drying apparatus 10 sufficiently larger than the volume of the 1st chamber 1. According to this, the 1st chamber 1 can be made to communicate rapidly, and the 2nd chamber 2 can communicate. That is, the liquid L can be rapidly placed under reduced pressure, so that the influence of the pressure reduction process on the film shape can be reduced.

The effect of the said Example 3 is as follows.

(1) In the vacuum drying method of the third embodiment, in the depressurization step (step S21), the control unit 20 closes the communication section 8 so that the first chamber 1 and the second chamber 2 are not in communication. In the state, the vacuum pump 6 is driven to reduce the second chamber 2 to the operating pressure Ps. Then, in the communication process (step S23), the control part 20 opens the communication valve 8, and makes the 2nd chamber 2 which reached the operating pressure Ps, and the 1st chamber 1 of substantially atmospheric pressure communicate. . In the discharging step (step S24), the control unit 20 continuously drives the vacuum pump 6 to discharge the vapor of the solvent that evaporates from the liquid body L. Subsequently, the vacuum valve 7 and the N ₂ valve 9 are opened and closed to perform a reduced pressure drying profile at which the set target pressure is set to evaporate the solvent. Therefore, the liquid L in the first chamber 1 is placed under a reduced pressure lowered to a predetermined operating pressure Ps at once without undergoing reduced-pressure drying, so that the ratio of the solute and the solvent changes and a shape gradient is likely to occur. It is possible to provide a rapid drying pressure reduction drying method in which the pressure reduction step is omitted, and the pressure drying step is carried out under reduced pressure in the range of the ratio of the solute and the solvent in which the membrane shape is stabilized.

(2) In the vacuum drying method of Example 3, the predetermined operating pressure Ps is set to be higher than the vapor pressure of the solvent of the liquid body. Therefore, abrupt dolby of a solvent can be suppressed and in-plane deviation of the film shape after drying by dolby can be reduced.

Next, the liquid crystal display device and the organic electroluminescent display device are demonstrated to an example about the manufacturing method, the electro-optical device, and the manufacturing method of the organic film which applied the vacuum drying method of this invention.

(Example 4)

(Liquid crystal display device and its manufacturing method)

10 is a schematic cross-sectional view showing the main components of the liquid crystal display device. As shown in FIG. 10, the liquid crystal display device 50 is a passive matrix liquid crystal display device, which includes a color filter substrate (CF substrate) 61 having a plurality of color layers 64 and a plurality of electrodes 68. The liquid crystal display panel 60 provided with the opposing board | substrate 71 and the liquid crystal 70 inserted between the CF board | substrate 61 and the opposing board | substrate 71 is provided. Since the liquid crystal display device 50 is a light receiving type display device, for example, a light source such as an LED element, an EL, a cold cathode tube or the like on the back side of the opposing substrate 71. It is provided with the illuminating device (not shown) which has a. In addition, the liquid crystal display device 50 of this embodiment is not limited to this, For example, the active matrix type | mold which provided the counter substrate 71 with switching elements, such as TFT (Thin Film transistor) and TFD (Thin Film Diode). A liquid crystal display device may be sufficient.

The counter substrate 71 uses a transparent resin or glass substrate, for example, and has a plurality of transparent electrodes 68 made of indium tin oxide (ITO) on the surface of the liquid crystal 70 side. The electrode 68 extends in the Y direction perpendicular to the transparent electrode 66 made of ITO provided on the opposing CF substrate 61. That is, the liquid crystal display panel 60 has the electrode 66 and the electrode 68 which are mutually opposed and orthogonal and are arrange | positioned at the grid | lattice form. The overlapping portions of the electrodes 66 and the electrodes 68 orthogonal to each other serve as pixel regions for display. Each electrode 66, 68 is formed by etching in a desired shape by the sputtering method using ITO as a target material.

The CF board | substrate 61 uses transparent resin or a glass substrate, for example, and is provided on the light shielding film 62 as a lower bank which is opened to the surface corresponding to a color element area | region, and the light shielding film 62 is provided. The upper bank 63 is provided. The color layer 64 as a color element corresponding to R (red), G (green), and B (blue) in the color element region partitioned by the upper bank 63, and the color layer 64 and the upper bank 63 OC (overcoat) layer 65 as a planarization layer which covers is provided. The electrode 66 is formed on the OC layer 65.

The light shielding film 62 may use, for example, an opaque metal such as Cr, Ni, Al, or a compound such as an oxide of these metals as a material. As a formation method, a film made of the above material is formed on the CF substrate 61 by vapor deposition or sputtering. What is necessary is just to set the film thickness in which the light shielding property is maintained according to the selected material. For example, if it is Cr, 100-200 nm is preferable. Then, the film is covered with a resist other than the portion corresponding to the opening portion 62a by the photolithography method, and the film is etched using an etching solution such as an acid corresponding to the material. Thereby, the light shielding film 62 which has the opening part 62a is formed.

The upper bank 63 is formed by applying an acrylic photosensitive resin material to the surface of the CF substrate 61 on which the light shielding film 62 is formed by a roll coat method or a spin coat method, and drying the film. The photosensitive resin layer which is 2 micrometers is formed. A mask provided with an opening having a size corresponding to the color element region is formed by facing and exposing the CF substrate 61 at a predetermined position.

The color layer 64 as a functional film is formed by giving three kinds (three colors) of functional liquids (liquid bodies) containing a color layer forming material to the color element region substantially partitioned by the upper bank 63, It forms into a film using the vacuum drying method in any one of Examples 1-3. Since the amount of solvent contained in a functional liquid is comparatively large, it is preferable to use the vacuum drying method of Example 1. The color layers 64 of the same color are arranged in the Y-axis direction, and the color layers 64 of different colors are arranged in parallel in the X-axis direction. It is a so-called striped color filter. The method of applying the three-color functional liquid uses a droplet ejection method in which each functional liquid is dropped into the color element region.

As the OC layer 65, a transparent acrylic resin material can be used. As a formation method, methods, such as a spin coat method and offset printing, are mentioned. The OC layer 65 is provided to alleviate the irregularities of the surface of the CF substrate 61 on which the color layer 64 is formed, and to planarize the electrode 66 formed on the surface later. Further, in order to ensure the adhesion to the electrode 66, it may be further bonded to form a thin film such as SiO ₂ on the OC layer 65.

The liquid crystal display panel 60 is such that the CF substrate 61 and the opposing substrate 71 are disposed to face each other at a predetermined interval via the gap member 72, and are bonded by using a sealing material not shown. In addition, the liquid crystal 70 is enclosed between two board | substrates 61 and 71 by the sealing material. On the side facing the liquid crystal 70 of the two board | substrates 61 and 71, the alignment film 67 and 69 which orientates the liquid crystal 70 in a predetermined direction is provided. The alignment films 67 and 69 as such functional films are formed by applying a functional liquid (liquid) containing a polyimide resin, for example, as an alignment film forming material, and reducing the pressure in any one of Examples 1 to 3. It is formed into a film using the drying method. Since the film thickness of the alignment films 67 and 69 after drying is about several hundred angstroms, and the amount of solvent contained in a functional liquid is comparatively small compared with the case where the color layer 64 is formed, the reduced pressure drying method of Example 2 is performed. It is preferable to use.

On the front and back surfaces of the liquid crystal display panel 60, generally, a polarizing plate for deflecting incident or exiting light, a retardation film as an optical functional film for improving the viewing angle, and the like are arranged. Although installed, these are omitted.

The effect of the said Example 4 is as follows.

(1) The manufacturing method of the color layer 64 as a functional film in the liquid crystal display device 50 of the said Example (4) gives three types of functional liquid containing a color layer formation material to a color element area | region, and implements the said, It is formed into a film using the reduced pressure drying method in any one of Examples 1-3. Therefore, since the evaporation rate of the solvent of the functional liquid is optimized under reduced pressure and dried under reduced pressure in a state where the in-plane vapor pressure distribution is approximately uniform, each color layer 64R, 64G, 64B).

(2) In the liquid crystal display device 50 of Example 4, the manufacturing method of the alignment films 67 and 69 as the functional films is coated with a functional liquid containing an alignment film forming material, and any of Examples 1 to 3 above. It is formed into a film using the vacuum drying method of the above. Therefore, since the evaporation rate of the solvent of the functional liquid is optimized under reduced pressure and is dried under reduced pressure in a state where the in-plane vapor pressure distribution is approximately uniform, the alignment films 67 and 69 having a substantially flat cross-sectional shape and less in-plane film thickness variation are obtained. Can be formed.

(3) In the manufacturing method of the liquid crystal display device 50 of the said Example 4, the color layer 64 and the alignment films 67 and 69 as a functional film use the reduced pressure drying method in any one of said Examples 1-3. It is manufactured using the manufacturing method of a film | membrane. Therefore, the liquid crystal display device 50 including the liquid crystal display panel 60 having each of the color layers 64R, 64G, and 64B and the alignment layers 67 and 69 having a substantially flat cross-sectional shape and small in-plane film thickness variation is manufactured. can do.

(4) The liquid crystal display device 50 of Example 4 is manufactured using a method for producing a functional film using the reduced pressure drying method of any one of Examples 1 to 3, wherein the cross-sectional shape is substantially flat and the in-plane film thickness The liquid crystal display panel 60 which has each color layer 64R, 64G, 64B with little dispersion | variation and the alignment films 67 and 69 is provided. Therefore, the liquid crystal display device 50 which has high display quality with few display unevennesses, such as the color unevenness of the color layer 64 and the orientation unevenness of the alignment films 67 and 69, can be provided.

(Example 5)

(Organic EL Display Device and Manufacturing Method thereof)

11 is a schematic cross-sectional view showing a main portion structure of an organic EL display device. As shown in FIG. 11, the organic EL display device 100 includes a substrate 101 having a light emitting element portion 117 and a sealing substrate 119 which is in close contact with the substrate 101 and the space 120 therebetween. Equipped. In addition, the substrate 101 includes a circuit element portion 103 on the element substrate 102, and the light emitting element portion 117 is formed on the circuit element portion 103 so as to overlap the circuit element portion 103. Is driven by. In the light emitting element portion 117, three color light emitting layers 117R, 117G, and 117B are formed in each color element region A, and have a stripe shape. The board | substrate 101 sets three color element area | regions A corresponding to three light emitting layers 117R, 117G, and 117B into a set of elements, and this element is the circuit element of the element substrate 102. It is arrange | positioned on the part 103 in matrix form. In the organic EL display device 100 of the present embodiment, light emission from the light emitting element portion 117 is emitted to the element substrate 102 side.

The sealing substrate 119 is made of glass or metal, is bonded to the substrate 101 via a sealing resin, and a getter agent 119a is attached to the sealed inner surface. The getter agent 119a absorbs water or oxygen that has entered the space 120 between the substrate 101 and the sealing substrate 119 and prevents the light emitting element portion 117 from being degraded by the water or oxygen that has entered. will be. In addition, you may abbreviate | omit this getter agent 119a.

The substrate 101 has a plurality of color element regions A on the circuit element portion 103 of the element substrate 102. The substrate 101 partitions the plurality of color element regions A and is stepped on the wall surface. And a two-layer bank 113 as a bank having an electrode, an electrode 112 formed in the plurality of color element regions A, and a hole injection transport layer 116 stacked on the electrode 112. Furthermore, the light emitting element part 117 which has the light emitting layer 117R, 117G, 117G as a color element formed by giving three types of functional liquids (liquid body) containing a light emitting layer forming material in the some color element area | region A is provided. Doing.

The two-layer bank 113 is composed of an upper bank 115 that substantially partitions the lower bank 114 and the color element region A, and the lower layer bank 114 protrudes inside the color element region A. FIG. It is provided and the level | step difference is formed in the wall surface of the two-layer bank 113.

As the formation method of the lower layer bank 114, the surface of each electrode 112 is masked using a resist etc. respectively corresponding to each light emitting layer 117R, 117G, 117B formed later, for example. In the masking device and the substrate 102 to a vacuum device, by sputtering or vacuum evaporation of SiO ₂ as a target or a raw material and a method of forming the lower layer bank 114. Masking of a resist or the like is peeled off later. In addition, since the lower layer bank 114 is formed of SiO ₂ , the film thickness is 200 nm or less, so that it has sufficient transparency, and even after the hole injection transport layer 116 and the light emitting layers 117R, 117G, and 117B are laminated, It does not inhibit luminescence.

As a method of forming the upper bank 115, for example, an acrylic photosensitive resin material is applied to the surface of the element substrate 102 on which the lower bank 114 is formed by a roll coating method or a spin coating method, and dried to have a thickness. The photosensitive resin layer which is about 2 micrometers is formed. A method of forming the upper bank 115 by exposing and developing a mask provided with an opening in a size corresponding to the color element region A by facing the element substrate 102 at a predetermined position is mentioned.

The method of forming each of the light emitting layers 117R, 117G, and 117B as a functional film includes three kinds of functional liquids (liquid bodies) containing the light emitting layer forming material in the color element region A substantially partitioned by the upper bank 115. Is applied using the droplet ejection method, and the functional liquid applied using the reduced pressure drying method in any one of the above Examples 1 to 3 is dried under reduced pressure to form a film. Therefore, the light emitting layers 117R, 117G, and 117B having substantially flat cross-sectional shapes and small in-plane film thickness variations are formed in the substrate 101.

The element substrate 102 is made of, for example, a transparent substrate such as glass, and a base protective film 102a made of a silicon oxide film is formed on the element substrate 102. The base protective film 102a is formed of polycrystalline silicon. An island-like semiconductor film 104 is formed. In the semiconductor film 104, a source region 104a and a drain region 104b are formed by high concentration P ion implantation. The portion where P is not introduced becomes the channel region 104c. In addition, a transparent gate insulating film 105 covering the underlying protective film 102a and the semiconductor film 104 is formed, and a gate electrode 106 made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 105. The transparent first interlayer insulating film 107 and the second interlayer insulating film 108 are formed on the gate electrode 106 and the gate insulating film 105. The gate electrode 106 is provided at a position corresponding to the channel region 104c of the semiconductor film 104. In addition, contact holes 109 and 110 which penetrate the first interlayer insulating film 107 and the second interlayer insulating film 108 and are respectively connected to the source region 104a and the drain region 104b of the semiconductor film 104 are formed. Formed. A transparent electrode 112 made of ITO or the like is patterned and disposed on the second interlayer insulating film 108, and one contact hole 109 is connected to the electrode 112. In addition, the other contact hole 110 is connected to the power supply line 111. In this way, the thin film transistor 103a for driving connected to each electrode 112 is formed in the circuit element part 103. As shown in FIG. In the circuit element section 103, a holding capacitor and a thin film transistor for switching are also formed, but these illustrations are omitted in FIG.

The light emitting element portion 117 includes an electrode 112 as an anode, a hole injection transport layer 116 sequentially stacked on the electrode 112, respective light emitting layers 117R, 117G, and 117B, and an upper bank 115. The cathode 118 laminated so as to cover the light emitting layers 117R, 117G and 117B is provided. In addition, when the cathode 118, the sealing substrate 119, and the getter agent 119a are made of a transparent material, light emitted from the sealing substrate 119 side can be emitted.

The organic EL display device 100 has a scanning line (not shown) connected to the gate electrode 106 and a signal line (not shown) connected to the source region 104a, and is a thin film transistor for switching by a scanning signal transmitted to the scanning line. When (not shown) is turned on, the potential of the signal line at that time is held at the holding capacitor, and the on / off state of the driving thin film transistor 103a is determined according to the state of the holding capacitor. Then, current flows from the power supply line 111 to the electrode 112 through the channel region 104c of the thin film transistor 103a for driving, and the hole injection transport layer 116 and the light emitting layers 117R, 117G, and 117B. Through the current flows further to the cathode 118 through. Each of the light emitting layers 117R, 117G, and 117B emits light in accordance with the amount of current flowing therein. The organic EL display device 100 can display desired characters, images, and the like by the light emitting mechanism of the light emitting element unit 117. Moreover, since the cross-sectional shape of each light emitting layer 117R, 117G, and 117B is equipped with the board | substrate 101 which is substantially flat, and there is little in-plane film thickness variation, the cross-sectional shape has a light emission unevenness by unevenness, brightness unevenness, etc. It has high display quality with few display defects.

The effect of the said Example 5 is as follows.

(1) In the organic EL display device 100 of Example 5, the manufacturing method of each of the light emitting layers 117R, 117G, and 117B as a functional film is obtained by coloring three functional liquids (liquid bodies) containing the light emitting layer forming material. It is given to the urea area | region A, and it forms into a film using the reduced pressure drying method in any one of said Examples 1-3. Therefore, since the evaporation rate of the solvent of the functional liquid is optimized under reduced pressure, and the in-plane vapor pressure distribution is dried under reduced pressure, the light emitting layers 117R, 117G, 117B).

(2) In the method for manufacturing the organic EL display device 100 of the fifth embodiment, each of the light emitting layers 117R, 117G, and 117B as a functional film is formed of a functional film using any one of the above-described vacuum drying methods. It is manufactured using the manufacturing method. Therefore, the organic EL display device 100 having the light emitting layers 117R, 117G, and 117B having a substantially flat cross-sectional shape and small in-plane film thickness variation can be manufactured.

(3) The organic EL display device 100 of the fifth embodiment is manufactured using the method for producing a functional film using the reduced pressure drying method of any one of the first to third embodiments, wherein the cross-sectional shape is almost flat and the in-plane film is formed. Each light emitting layer 117R, 117G, 117B with little thickness variation is provided. Therefore, the organic EL display device 100 having high display quality with little display unevenness such as light emission unevenness or luminance unevenness of each of the light emitting layers 117R, 117G, and 117B can be provided.

(Example 6)

Next, the specific example of the electronic device which mounts the liquid crystal display device of Example 4 or the organic electroluminescence display of Example 5 is demonstrated. 12 is a schematic perspective view of a portable information processing apparatus as an electronic apparatus. As shown in FIG. 12, the portable information processing apparatus 200 as an electronic apparatus of this embodiment is provided with the information processing apparatus main body 203 and the display part 202 which have the keyboard 201 for input. The liquid crystal display device 50 or the organic EL display device 100 is mounted on the display unit 202.

The effect of the said Example 6 is as follows.

(1) The portable information processing apparatus 200 as the electronic apparatus of the sixth embodiment has a high display quality with a small display unevenness such as color unevenness or orientation unevenness of the fourth embodiment, or an embodiment The organic electroluminescence display 100 which has high display quality with few display nonuniformities, such as the light emission nonuniformity and luminance nonuniformity of 5, is mounted. Therefore, the portable information processing apparatus 200 which can express information, such as an image, with high display quality can be provided.

Modifications other than the said Examples 1-6 are as follows.

(Modification 1) In the reduced-pressure drying method of Example 3, the initial pressure P ₁ of the first chamber 1 is not limited to atmospheric pressure 1 atm. For example, pressure reduction is started in the state which made the 1st chamber 1 and the 2nd chamber 2 communicate, and the communication valve 8 is closed by the pressure reduction value intermediate | middle of operation pressure Ps and atmospheric pressure, and a 1st chamber (1) is sealed. Thereafter, the second chamber 2 may communicate with the first chamber 1 after reaching the operating pressure Ps. According to this, it is possible to shorten the time when the pressure P ₁ of the 1st chamber 1 after communication reaches the pressure P ₂ of the 2nd chamber 2. That is, it is possible to complete one decompression drying operation in a shorter time.

(Modification 2) In the vacuum drying method of Examples 1 to 3, the solvent is evaporated by mounting the substrate W coated with the liquid L on the mounting table 11 of the first chamber 1 and reducing the pressure. Although it is made, it is not limited to this. For example, heating means such as a heater may be provided on the mounting table 11, and a heating step of heating the substrate W in a reduced pressure drying process may be provided. According to this, by heating the board | substrate W uniformly by a heating means in a heating process and promoting evaporation of a solvent, it becomes possible to fix the shape of the liquid L more quickly.

(Modification 3) The to-be-dried product dried under the reduced pressure drying method of Examples 1-3 is not limited to the board | substrate W to which the liquid L was apply | coated. For example, a round object such as a semiconductor wafer or spectacle lens may be supported by a jig or the like and accommodated therein.

(Modification 4) It is good also as a pressure reduction drying method combining the pressure reduction drying methods of said each Example 1-3. For example, you may replace the pressure reduction process of Example 1 or 2 with the pressure reduction process of Example 3. That is, after reaching the predetermined operating pressure Ps by depressurizing the 2nd chamber 2 in the state which sealed the 1st chamber 1, the 1st chamber 1 and the 2nd chamber 2 in a communication process. To communicate. Then, when the first chamber 1 is sealed and the solvent of the liquid L is dried in the standing process, the decompression process for reaching the predetermined operating pressure Ps is shortened, and the decompression of the evaporation amount control type or the film shape control type is reduced. It is possible to provide a drying method. For example, in the state where the liquid L was dried by the reduced pressure drying method of Example 1 or 2 and the membrane shape was stabilized, the remaining solvent may be evaporated by performing the reduced pressure drying method of Example 3. .

(Modification 5) In the liquid crystal display device 50 of Example 4, the functional film formed by using the vacuum drying method of any one of the above embodiments 1 to 3 is limited to the color layers 64 and the alignment films 67 and 69. It doesn't work. For example, it is applicable also in formation of the OC layer 65 which apply | coats and dries the liquid body containing an OC formation material. In addition, in the formation of any of these functional films, any of the above-described vacuum drying methods in Examples 1-3 may be used.

(Modified Example 6) The electronic device equipped with the liquid crystal display device 50 of Example 4 or the organic EL display device 100 of Example 5 is not limited to the portable information processing apparatus 200 of Example 6. FIG. For example, a mobile phone, a portable information device called a PDA (Personal Digital Assistants) or a portable terminal device, a portable PC, a word processor, a digital still camera, a vehicle monitor, a digital video camera, a liquid crystal TV, a viewfinder type, a monitor And a device using a liquid crystal display device or an organic EL display device that is an electro-optical device such as a direct-view video tape recorder, a car navigation device, a wireless pager, an electronic notebook, a calculator, a workstation, a TV phone, a POS terminal, and the like.

According to the present invention, in the drying process, it is possible to optimize the evaporation rate of the solvent of the applied liquid according to the type of liquid, and to perform the vacuum drying in a substantially uniform state in the surface on which the vapor pressure distribution of the solvent is applied. The pressure reduction drying method which can be used, the manufacturing method of the functional film which utilized this pressure reduction drying method, the manufacturing method of an electro-optical device, an electro-optical device, a liquid crystal display device, an organic electroluminescence display, and an electronic device can be provided.

Claims (20)

A liquid body coated on a substrate by using a pressure reduction drying device having a second chamber capable of pressure reduction by a pressure reduction means and a first chamber communicating with the second chamber. As a vacuum drying method of evaporating the solvent of) under evaporation under reduced pressure, A decompression step of communicating the first chamber and the second chamber in a state where the base material is accommodated in the first chamber, and decompressing by the decompression means to an operating pressure higher than the vapor pressure of the solvent of the liquid; When the operating pressure is reached, the first chamber is sealed, the solvent is evaporated, and the first chamber is subjected to the vapor pressure when the predetermined amount of the solvent evaporates in the closed first chamber. The leaving process to stand until the pressure rises, A communication step of causing the first chamber and the second chamber to rise at the pressure; And a discharge step of discharging the vapor of the solvent diffused into the first chamber and the second chamber by the decompression means. delete The method of claim 1, At the said discharge process, it exhausts under pressure higher than the said pressure, The pressure reduction drying method characterized by the above-mentioned. The method of claim 1, Repeating the said discharge process from the said decompression process, and drying the said liquid body apply | coated to the said base material, The reduced pressure drying method characterized by the above-mentioned. A pressure reduction drying method in which a solvent of a liquid applied to a substrate is evaporated and dried under reduced pressure by using a pressure reduction drying apparatus having a second chamber that can be decompressed by a decompression means and a first chamber that can communicate with the second chamber. In a state where the substrate is accommodated in the first chamber, the first chamber and the second chamber communicate with each other, and the solvent is evaporated from the liquid body and thickened until just before the viscosity affecting the film shape. A decompression step of reducing the pressure to an operating pressure, At the step of reaching the operating pressure, the first chamber is sealed, and the evaporation of the solvent proceeds so that the first chamber adds the operating pressure to the saturated evaporation pressure of the solvent of the liquid in the first chamber. The leaving process to stand until the pressure rises, A communication step of causing the first chamber and the second chamber to rise at the pressure; And a discharge step of discharging the vapor of the solvent diffused into the first chamber and the second chamber by the decompression means. delete The method according to claim 1 or 5, In the communication step, the first chamber that has risen at the pressure is in communication with the second chamber having a larger volume than the first chamber. The method according to claim 1 or 5, And the second chamber is depressurized to a pressure less than the operating pressure prior to the communication step. A pressure reduction drying method in which a solvent of a liquid applied to a substrate is evaporated and dried under reduced pressure by using a pressure reduction drying apparatus having a second chamber that can be decompressed by a decompression means and a first chamber that can communicate with the second chamber. Decompressing the second chamber in a non-communication state with the first chamber by a decompression means to an operating pressure higher than the vapor pressure of the solvent of the liquid body in the state where the substrate is accommodated in the first chamber. Decompression process, A communication step of communicating the first chamber and the second chamber when the second chamber reaches the operating pressure; And a discharge step of discharging the vapor of the solvent diffused into the first chamber and the second chamber. delete The method according to any one of claims 1, 5, or 9, In the discharge step, if the liquid is dried and the film is thickened to a degree where the film shape is fixed, the exhaust gas is discharged positively to increase the exhaust speed of the pressure reducing means. The method according to any one of claims 1, 5, or 9, In the discharge step, an inert gas is introduced into the first chamber from the outside so that the first chamber is not decompressed below the operating pressure. The method according to any one of claims 1, 5, or 9, In the discharging step, after discharging the vapor of the solvent of the first chamber into the second chamber and then closing the first chamber, the vapor of the solvent diffused into the second chamber by the decompression means is discharged. A vacuum drying method characterized by the above-mentioned. As a manufacturing method of the functional film which apply | coats a liquid body containing a functional material to a base material, it dries, and forms a functional film on the surface of the said base material, The said liquid body is dried using the vacuum drying method in any one of Claims 1, 5, or 9, The manufacturing method of the functional film characterized by the above-mentioned. A manufacturing method of an electro-optical device having a pair of substrates and provided with a functional film constituting pixels on at least one substrate, The said functional film is formed using the manufacturing method of the functional film of Claim 14, The manufacturing method of the electro-optical device characterized by the above-mentioned. An electro-optical device having a pair of substrates and having a functional film constituting pixels on at least one substrate, The said functional film was formed using the manufacturing method of the electro-optical device of Claim 15, The electro-optical device characterized by the above-mentioned. A liquid crystal display device having a pair of substrates having electrodes, an alignment film serving as a functional film covering the electrode at least in a range corresponding to the display region, and a liquid crystal inserted between the pair of substrates through the alignment film, The said alignment film was formed using the manufacturing method of the functional film of Claim 14, The liquid crystal display device characterized by the above-mentioned. A liquid crystal display device having a pair of substrates, a color element as a functional film partitioned by at least one substrate by partition walls, and a liquid crystal inserted between the pair of substrates, The said color element was formed using the manufacturing method of the functional film of Claim 14, The liquid crystal display device characterized by the above-mentioned. An organic EL display device having a pair of substrates and a light emitting layer as a functional film partitioned on at least one substrate by partition walls, The said light emitting layer was formed using the manufacturing method of the functional film of Claim 14, The organic electroluminescence display characterized by the above-mentioned. An electronic apparatus comprising the electro-optical device according to claim 16 mounted thereon.

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