JP2020205273A - Inspection device, reduced-pressure drying device, and method for controlling reduced-pressure drying device - Google Patents

Abstract

To provide: an inspection device capable of detecting a dry condition in a coated region at an early stage, the coated region being coated with an organic material on a substrate; a reduced-pressure drying device; and a method for controlling a reduced-pressure drying device.SOLUTION: An inspection device according to one aspect of an embodiment includes an imaging section and a dry-condition detection section. The imaging section images a coated region where an organic material is coated on a substrate. The dry-condition detection section detects a dry condition of the coated region on the basis of the color density in the coated region imaged by the imaging section.SELECTED DRAWING: Figure 13

Description

The disclosed embodiments relate to control methods for inspection devices, vacuum drying devices and vacuum drying devices.

Conventionally, an organic light emitting diode (OLED: Organic Light Emitting Diode), which is a light emitting diode utilizing light emission of organic EL (Electroluminescence), is known. An organic EL display using an organic light emitting diode has advantages such as thinness, light weight, low power consumption, and excellent response speed, viewing angle, and contrast ratio. For this reason, it has been attracting attention in recent years as a next-generation flat panel display (FPD).

The organic light emitting diode has a structure in which an organic EL layer is sandwiched between an anode and a cathode on a substrate. The organic EL layer is formed by laminating, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in this order from the anode side. In such a laminated structure, for example, the hole injection layer, the hole transport layer, and the light emitting layer are each formed by applying an organic material on a substrate by an inkjet method and drying the substrate to which the organic material is applied under reduced pressure. (See, for example, Patent Document 1).

By the way, the drying time until the above-mentioned drying is completed varies depending on various factors such as the type and amount of the organic material applied to the substrate and the surface condition of the substrate. Therefore, for example, in the case of mass-producing organic light emitting diodes, it is necessary to set the optimum drying time in advance.

In the prior art, for example, a large number of samples were prepared while changing the drying treatment time little by little, and the film thickness and optical characteristics of each layer of the prepared samples were measured. Then, when a sample with good measurement results was obtained, it was estimated that the drying was surely completed, and the time of the drying treatment performed on the sample was set as the optimum drying time.

Japanese Unexamined Patent Publication No. 2000-181079

However, in the prior art, a large amount of time is required because the dry state of the substrate is detected by measuring the film thickness and the optical characteristics after preparing the sample. Therefore, there is room for improvement in the prior art in that the dry state of the substrate is detected at an early stage.

One aspect of the embodiment is to provide a control method for an inspection device, a vacuum drying device, and a vacuum drying device that can detect a dry state of a coated region coated with an organic material on a substrate at an early stage.

The inspection device according to one aspect of the embodiment includes an imaging unit and a dry state detecting unit. The image pickup unit takes an image of the coating area on which the organic material is applied on the substrate. The dry state detection unit detects the dry state of the coating region based on the color density of the coating region imaged by the imaging unit.

According to one aspect of the embodiment, the dry state of the coated region coated with the organic material on the substrate can be detected at an early stage.

FIG. 1 is a schematic cross-sectional view showing an outline of the configuration of an organic light emitting diode. FIG. 2 is a schematic plan view showing an outline of the configuration of a bank of organic light emitting diodes. FIG. 3 is a flowchart showing a main process of a method for manufacturing an organic light emitting diode. FIG. 4 is a schematic plan view showing an outline of the configuration of the substrate processing system according to the present embodiment. FIG. 5A is a schematic cross-sectional view showing a substrate coated with an organic material for forming a hole injection layer. FIG. 5B is a schematic cross-sectional view showing a substrate that has been vacuum dried in a vacuum drying apparatus. FIG. 6A is a schematic cross-sectional view showing a substrate coated with an organic material for forming a hole transport layer. FIG. 6B is a schematic cross-sectional view showing a substrate that has been vacuum dried in a vacuum drying apparatus. FIG. 7A is a schematic cross-sectional view showing a substrate coated with an organic material for forming a light emitting layer. FIG. 7B is a schematic cross-sectional view showing a substrate that has been vacuum dried in a vacuum drying apparatus. FIG. 8 is a schematic plan view showing the configuration of the vacuum drying apparatus according to the present embodiment. FIG. 9 is a schematic cross-sectional view taken along line IX-IX of FIG. FIG. 10 is a block diagram of the control device. FIG. 11 is a schematic enlarged view showing a part of the captured image captured by the imaging unit in an enlarged manner. FIG. 12 is a graph showing the color density measured by the color density measuring unit during the vacuum drying process. FIG. 13 is a flowchart showing a processing procedure of a process of setting a drying time in a vacuum drying device provided with an inspection device according to the present embodiment. FIG. 14 is a graph showing the G color density of the coating region in the peripheral portion and the coating region in the central portion. FIG. 15 is a schematic enlarged cross-sectional view showing the vicinity of the image pickup unit of the image pickup unit according to the second embodiment.

Hereinafter, embodiments of the inspection device, the vacuum drying device, and the control method of the vacuum drying device disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

(First Embodiment)
<1. Configuration and manufacturing method of organic light emitting diode>
First, the outline of the configuration of the organic light emitting diode and the manufacturing method thereof will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic cross-sectional view showing an outline of the configuration of the organic light emitting diode 500. FIG. 2 is a schematic plan view showing an outline of the configuration of the bank 540 of the organic light emitting diode 500. FIG. 3 is a flowchart showing a main process of a method for manufacturing the organic light emitting diode 500.

As shown in FIG. 1, the organic light emitting diode 500 has a structure in which an organic EL layer 530 is sandwiched between an anode 510 and a cathode 520 on a glass substrate G (hereinafter, referred to as “substrate G”) as a substrate. Have.

The organic EL layer 530 is formed by laminating the hole injection layer 531, the hole transport layer 532, the light emitting layer 533, the electron transport layer 534, and the electron injection layer 535 in this order from the anode 510 side.

Specifically, first, in the anode forming process (step S101 in FIG. 3), the anode 510 is formed on the substrate G. The anode 510 is formed, for example, by using a vapor deposition method. For the anode 510, for example, a transparent electrode made of ITO (Indium Tin Oxide) is used.

Subsequently, in the bank forming process (step S102 in FIG. 3), the bank 540 is formed on the anode 510. The bank 540 is patterned into a predetermined pattern by, for example, a photolithography process or an etching process.

As shown in FIG. 2, a plurality of banks 540 are formed in the row direction and the column direction. Then, inside the bank 540, the organic EL layer 530 and the cathode 520 are laminated to form pixels as described later. For the bank 540, for example, a photosensitive polyimide resin is used.

Subsequently, the organic EL layer 530 is formed on the anode 510 in the bank 540. Specifically, in the hole injection layer forming process (step S103 in FIG. 3), the hole injection layer 531 is formed on the anode 510. Then, in the hole transport layer forming process (step S104 in FIG. 3), the hole transport layer 532 is formed on the hole injection layer 531.

Then, in the light emitting layer forming process (step S105 in FIG. 3), the light emitting layer 533 is formed on the hole transport layer 532. The light emitting layer 533 includes an R color light emitting layer (red light emitting layer), a G color light emitting layer (green light emitting layer), and a B color light emitting layer (blue light emitting layer).

Subsequently, in the electron transport layer forming process (step S106 of FIG. 3), the electron transport layer 534 is formed on the light emitting layer 533, and in the electron injection layer forming process (step S107 of FIG. 3), the electron transport layer 534 is formed. The electron injection layer 535 is formed.

In the present embodiment, the hole injection layer 531 and the hole transport layer 532 and the light emitting layer 533 are each formed in the substrate processing system 100 described later. In the substrate processing system 100, an organic material coating process, a vacuum drying process of the organic material, and a firing process of the organic material are sequentially performed by an inkjet method, and these hole injection layer 531, hole transport layer 532, and light emitting layer 533 are formed. It is formed. The formation of the hole injection layer 531, the hole transport layer 532, and the light emitting layer 533 will be described later with reference to FIGS. 4 to 7B and the like.

Further, the electron transport layer 534 and the electron injection layer 535 are each formed by, for example, a thin film deposition method.

Then, in the cathode forming process (step S108 in FIG. 3), the cathode 520 is formed on the electron injection layer 535. The cathode 520 is formed, for example, by using a vapor deposition method. For the cathode 520, for example, aluminum is used.

Then, a sealing process is performed in order to block the laminated structure formed through steps S101 to S108 from moisture and the like in the atmosphere (step S109 in FIG. 3).

In the organic light emitting diode 500 manufactured through such a film forming step to a sealing step, a predetermined quantity of light emitted by the hole injection layer 531 is injected by applying a voltage between the anode 510 and the cathode 520. Holes are transported to the light emitting layer 533 via the hole transport layer 532.

Further, a predetermined number of electrons injected in the electron injection layer 535 are transported to the light emitting layer 533 via the electron transport layer 534. Then, holes and electrons are recombined in the light emitting layer 533 to form an excited molecule, and the light emitting layer 533 emits light.

<2. Substrate processing system configuration>
Next, the configuration of the substrate processing system 100 including the inspection device and the vacuum drying device according to the present embodiment will be described with reference to FIG. FIG. 4 is a schematic plan view showing an outline of the configuration of the substrate processing system 100 according to the present embodiment. In FIG. 4, in order to show the inspection device 200 in an easy-to-understand manner, the inspection device 200 is schematically shown by painting with a predetermined pattern.

In the following, in order to clarify the positional relationship, the X-axis direction, the Y-axis direction, and the Z-axis direction that are orthogonal to each other are defined, and the Z-axis positive direction is defined as the vertically upward direction.

As shown in FIG. 4, the substrate G on which the anode 510 and the bank 540 are formed is carried into the substrate processing system 100 through an anode forming process and a bank forming process (see steps S101 and S102 in FIG. 3) in advance. Then, in the substrate processing system 100, each processing corresponding to steps S103 to S105 of FIG. 3 is performed, and after the hole injection layer 531 and the hole transport layer 532 and the light emitting layer 533 are formed on the substrate G, electrons are formed. It is carried out for the transport layer forming process (see step S106 of FIG. 3).

As shown in FIG. 4, the substrate processing system 100 has a configuration in which the carry-in station 110, the processing station 120, and the carry-out station 130 are integrally connected. The carry-in station 110 carries in a plurality of substrates G from the outside in units of cassettes C, and takes out the substrate G before processing from the cassette C.

The processing station 120 includes a hole injection layer forming block 121 that performs a hole injection layer forming process on the substrate G, and a hole that performs a hole transport layer forming process on the substrate G after the hole injection layer forming process. It includes a transport layer forming block 122. Further, the processing station 120 includes a light emitting layer forming block 123 that performs a light emitting layer forming process on the substrate G after the hole transport layer forming process.

The unloading station 130 stores the processed substrate G in the cassette C, and unloads the plurality of substrates G to the outside in units of the cassette C.

The carry-in station 110, the hole injection layer forming block 121, the hole transport layer forming block 122, the light emitting layer forming block 123, and the carry-out station 130 are arranged side by side in this order from the negative X-axis direction to the positive X-axis direction.

The carry-in station 110 includes a cassette mounting table 111, a transport path 112, and a substrate transport body 113. The cassette mounting table 111 can mount a plurality of cassettes C in a row in the Y-axis direction.

The transport path 112 is provided so as to extend in the Y-axis direction. The substrate transport body 113 is provided so as to be movable on the transport path 112 and movable in the Z-axis direction and around the Z-axis, and transports the substrate G between the cassette C and the processing station 120. The substrate transport body 113 transports the substrate G while adsorbing and holding the substrate G, for example.

In the processing station 120, the hole injection layer forming block 121 includes a coating device 121a, a buffer device 121b, a vacuum drying device 121c, a heat treatment device 121d, and a temperature control device 121e.

The coating device 121a is a device for coating an organic material for forming the hole injection layer 531 on the anode 510 formed on the substrate G. FIG. 5A is a schematic cross-sectional view showing a substrate G coated with an organic material for forming the hole injection layer 531.

As shown in FIG. 5A, in the coating device 121a, the organic material is coated at a predetermined position on the substrate G, that is, inside the bank 540 by an inkjet method. Such an organic material is a solution in which a predetermined material for forming the hole injection layer 531 is dissolved in an organic solvent.

The buffer device 121b shown in FIG. 4 is a device that temporarily accommodates a plurality of substrates G. The vacuum drying device 121c is a device for vacuum drying the organic material coated by the coating device 121a.

FIG. 5B is a schematic cross-sectional view showing the substrate G dried under reduced pressure in the vacuum drying device 121c. As can be seen from the comparison between FIGS. 5A and 5B, the solvent of the organic material applied to the inside of the bank 540 is removed by vacuum drying, so that the hole injection layer 531 having a uniform or substantially uniform film thickness is an anode 510. It will be in a state of being stacked on top.

The heat treatment apparatus 121d shown in FIG. 4 is an apparatus for heat-treating and firing an organic material dried by the vacuum drying apparatus 121c. For example, the heat treatment apparatus 121d has a chamber capable of accommodating the substrate G and a hot plate (not shown) arranged in the chamber, and fires an organic material by heat from the hot plate.

The temperature control device 121e is a device that adjusts the substrate G heat-treated by the heat treatment device 121d to a predetermined temperature, for example, room temperature. The arrangement and number of the coating device 121a, the buffer device 121b, the vacuum drying device 121c, the heat treatment device 121d, and the temperature control device 121e in the hole injection layer forming block 121 can be arbitrarily selected.

Further, the hole injection layer forming block 121 includes substrate transport regions CR1 to CR3 and delivery devices TR1 to TR3. The substrate transfer regions CR1 to CR3 are, for example, transfer robots, and transfer the substrate G to each device provided adjacent to each other.

Specifically, the substrate transport region CR1 transports the substrate G to the coating device 121a and the buffer device 121b adjacent to the substrate transport region CR1. Further, the substrate transport region CR2 transports the substrate G to the vacuum drying device 121c adjacent to the substrate transport region CR2.

Further, the substrate transport region CR3 transports the substrate G to the heat treatment apparatus 121d and the temperature control device 121e adjacent to the substrate transport region CR3. In the substrate transport regions CR1 to CR3, substrate transport devices (not shown) for transporting the substrate G are provided so as to be movable in the horizontal direction, the vertical direction, and around the vertical axis.

The delivery devices TR1 to TR3 are provided in order between the carry-in station 110 and the board transfer area CR1, between the board transfer areas CR1 and CR2, and between the board transfer areas CR2 and CR3, and transfer the board G between them. ..

The hole transport layer forming block 122 includes a coating device 122a, a buffer device 122b, a vacuum drying device 122c, a heat treatment device 122d, and a temperature control device 122e. The coating device 122a coats the organic material for forming the hole transport layer 532 on the hole injection layer 531 formed on the substrate G. FIG. 6A is a schematic cross-sectional view showing a substrate G coated with an organic material for forming the hole transport layer 532.

As shown in FIG. 6A, in the coating device 122a, the organic material is coated at a predetermined position on the substrate G, that is, inside the bank 540 by an inkjet method. Such an organic material is a solution in which a predetermined material for forming the hole transport layer 532 is dissolved in an organic solvent.

Since the buffer device 122b and the vacuum drying device 122c shown in FIG. 4 have substantially the same configurations as the buffer device 121b and the vacuum drying device 121c, detailed description thereof will be omitted.

FIG. 6B is a schematic cross-sectional view showing the substrate G that has been vacuum dried in the vacuum drying apparatus 122c. As can be seen from the comparison between FIGS. 6A and 6B, the organic material applied to the inside of the bank 540 is dried under reduced pressure to remove the solvent, so that the hole transport layer 532 having a uniform or substantially uniform film thickness has holes. It is in a state of being laminated on the injection layer 531.

Further, since the heat treatment device 122d and the temperature control device 122e have almost the same configurations as the heat treatment device 121d and the temperature control device 121e, detailed description thereof will be omitted. However, in the hole transport layer forming block 122, the insides of the heat treatment device 122d and the temperature control device 122e are maintained in a low oxygen and low dew point atmosphere.

Here, the low oxygen atmosphere means an atmosphere having an oxygen concentration lower than that of the atmosphere, for example, an atmosphere having an oxygen concentration of 10 ppm or less. Further, the low dew point atmosphere means an atmosphere in which the dew point temperature is lower than the atmosphere, for example, an atmosphere in which the dew point temperature is −10 ° C. or lower. The low oxygen and low dew point atmosphere is maintained by using an inert gas such as nitrogen gas.

In the hole transport layer forming block 122, the number and arrangement of the coating device 122a, the buffer device 122b, the vacuum drying device 122c, the heat treatment device 122d, and the temperature control device 122e can be arbitrarily selected.

Further, the hole transport layer forming block 122 includes substrate transport regions CR4 to CR6 and delivery devices TR5 and TR6. The hole injection layer forming block 121 and the hole transport layer forming block 122 are connected via the delivery device TR4.

Here, since the substrate transport areas CR4 to CR6 and the delivery devices TR4 to TR6 have substantially the same configurations as the board transfer areas CR1 to CR3 and the delivery devices TR1 to TR3 described above, detailed description thereof will be omitted.

However, as described above, since the inside of the heat treatment device 122d and the temperature control device 122e is maintained in a low oxygen and low dew point atmosphere, the inside of the substrate transport region CR6 is also maintained in a low oxygen and low dew point atmosphere.

Further, the delivery device TR6 that connects the substrate transport region CR6 and the substrate transport region CR5 temporarily accommodates the substrate G and can switch the internal atmosphere, that is, switch between a low oxygen and low dew point atmosphere and an air atmosphere. It is configured as a load lock device provided as possible.

The light emitting layer forming block 123 includes a coating device 123a, a buffer device 123b, a vacuum drying device 123c, a heat treatment device 123d, and a temperature control device 123e.

The coating device 123a is a device for coating an organic material for forming the light emitting layer 533 on the hole transport layer 532 formed on the substrate G. FIG. 7A is a schematic cross-sectional view showing a substrate G coated with an organic material for forming the light emitting layer 533.

As shown in FIG. 7A, in the coating device 123a, the organic material is coated at a predetermined position on the substrate G, that is, inside the bank 540 by an inkjet method. Such an organic material is a solution in which a predetermined material for forming the light emitting layer 533 is dissolved in an organic solvent. In FIG. 7A, the R color light emitting layer of the light emitting layer 533 is designated by reference numeral 533R, the G color light emitting layer is designated by reference numeral 533G, and the B color light emitting layer is designated by reference numeral 533B.

Since the buffer device 123b and the vacuum drying device 123c shown in FIG. 4 have substantially the same configurations as the buffer device 122b and the vacuum drying device 122c described above, detailed description thereof will be omitted.

FIG. 7B is a schematic cross-sectional view showing the substrate G that has been vacuum dried in the vacuum drying apparatus 123c. As can be seen from the comparison between FIGS. 7A and 7B, the solvent of the organic material applied to the inside of the bank 540 is removed by drying under reduced pressure, so that the light emitting layer 533 having a uniform or substantially uniform film thickness is a hole transport layer. It is in a state of being laminated on 532.

Each of the vacuum drying devices 121c, 122c, and 123c described above is provided with an inspection device 200 for detecting the dry state of the substrate G. The detailed configurations of the vacuum drying devices 121c, 122c, 123c and the inspection device 200 will be described later with reference to FIGS. 8 and 9.

Continuing the description of FIG. 4, since the buffer device 123b and the vacuum drying device 123c have almost the same configurations as the buffer device 122b and the vacuum drying device 122c, detailed description thereof will be omitted.

In the light emitting layer forming block 123, the number and arrangement of the coating device 123a, the buffer device 123b, the vacuum drying device 123c, the heat treatment device 123d, and the temperature control device 123e can be arbitrarily selected.

The light emitting layer forming block 123 includes substrate transport areas CR7 to CR9 and delivery devices TR8 to TR10. The hole transport layer forming block 122 and the light emitting layer forming block 123 are connected via the delivery device TR7.

Here, since the substrate transport areas CR7 to CR9 and the delivery devices TR7 to TR9 have substantially the same configurations as the substrate transfer areas CR4 to CR6 and the delivery devices TR4 to TR6 described above, detailed description thereof will be omitted.

The delivery device TR10 is provided between the substrate transport region CR9 and the unloading station 130, and the substrate G is delivered between these. The delivery device TR10 may be configured as a load lock device that temporarily accommodates the substrate G and is provided so that the internal atmosphere can be switched, that is, the atmosphere can be switched between a low oxygen and low dew point atmosphere and an atmospheric atmosphere. preferable.

The unloading station 130 includes a cassette mounting table 131, a transport path 132, and a substrate transport body 133. The cassette mounting table 131 can mount a plurality of cassettes C in a row in the Y-axis direction.

The transport path 132 is provided so as to extend in the Y-axis direction. The substrate transport body 133 is provided so as to be movable on the transport path 132 and movably in the Z-axis direction and around the Z-axis, and transports the substrate G between the processing station 120 and the cassette C. The substrate transport body 133 transports the substrate G while adsorbing and holding the substrate G, for example. Further, it is preferable that the inside of the carry-out station 130 is maintained in a low oxygen and low dew point atmosphere.

Further, the substrate processing system 100 includes a control device 140. The control device 140 is, for example, a computer, and includes a control unit 141 and a storage unit 142. The storage unit 142 stores programs that control various processes executed in the substrate processing system 100. The control unit 141 is, for example, a CPU (Central Processing Unit), and controls the operation of the substrate processing system 100 by reading and executing a program stored in the storage unit 142.

The program may be recorded on a storage medium readable by a computer, and may be installed from the storage medium in the storage unit 142 of the control device 140. Examples of storage media that can be read by a computer include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnet optical disk (MO), and a memory card. The control unit 141 may be configured only by hardware without using a program. The specific configuration of the control device 140 will be described later with reference to FIG.

By the way, in the above-mentioned vacuum drying apparatus 121c, 122c, 123c, the drying time until the drying is completed is, for example, the type and amount of the organic material applied to the substrate G, the surface state of the substrate G, and the type of the layer to be formed. It depends on various factors such as. Therefore, for example, in the case of mass-producing the organic light emitting diode 500, it is necessary to set the optimum drying time in advance.

In the conventional technique, a large number of samples are prepared, and the optimum drying time is set by measuring the film thickness and optical characteristics of each layer of the prepared samples, so that the setting work takes time.

Therefore, the vacuum drying devices 121c, 122c, and 123c according to the present embodiment are provided with an inspection device 200 for detecting the dry state of the coated region coated with the organic material on the substrate G. Then, in the inspection device 200, the coating area of the substrate G is imaged, the color density of the imaged coating area is measured, and the dry state of the coating area is detected based on the measured color density. I made it.

As described above, the vacuum drying devices 121c, 122c, 123c are provided with the inspection device 200 that detects the dry state based on the color density of the coating area, so that the dry state of the coating area can be detected at an early stage. In addition, this makes it possible to improve the efficiency of the work of setting the optimum drying time.

<3. Configuration of inspection device and vacuum drying device>
Hereinafter, the configurations of the vacuum drying devices 121c, 122c, 123c provided with the inspection device 200 according to the present embodiment will be described with reference to FIGS. 8 and 9. FIG. 8 is a schematic plan view showing the configuration of the vacuum drying device 123c according to the present embodiment, and FIG. 9 is a schematic cross-sectional view taken along the line IX-IX of FIG.

Although the vacuum drying device 123c will be described here as an example, since the vacuum drying devices 121c, 122c, 123c have almost the same configuration, the following description is also applicable to the vacuum drying devices 121c, 122c.

As shown in FIGS. 8 and 9, the vacuum drying device 123c includes a chamber 150, a substrate holding mechanism 160 (see FIG. 9), a pressure reducing mechanism 170 (see FIG. 9), and an inspection device 200.

The chamber 150 is a substantially rectangular parallelepiped processing container whose inside can be sealed. As shown in FIG. 9, the chamber 150 accommodates a substrate G or the like held by the substrate holding mechanism 160. Further, the chamber 150 is provided with an opening 151 and a window 152. Specifically, a plurality of openings 151 are provided in the ceiling portion 150a of the chamber 150, and a window portion 152 is attached to each of the openings 151.

The window portion 152 is glass having a translucency such that the substrate G inside the chamber 150 can be imaged from the outside of the chamber 150 by the imaging units 11a to 11c (described later). The window portion 152 is formed of, for example, quartz glass, but is not limited thereto. Further, the number and arrangement of the openings 151 and the windows 152 can be arbitrarily selected.

The board holding mechanism 160 includes a holding portion 161, a strut portion 162, and an elevating portion 163. The holding unit 161 is a stage. Specifically, the holding portion 161 is provided with a plurality of flat plate-shaped members, and the substrate G is placed and held. In the example shown in FIG. 9, the number of flat plate-shaped members is 5, but the number is not limited to this. Further, the number of flat plate-shaped members constituting the holding portion 161 may be one.

The strut portion 162 is a member extending in the vertical direction, the base end portion is connected to the elevating portion 163, and the holding portion 161 is horizontally supported at the tip portion. The elevating portion 163 is a drive source for, for example, an electric motor, and elevates and elevates the strut portion 162 and the holding portion 161 in the vertical direction. As a result, the substrate G held by the holding portion 161 is moved up and down. The number of elevating parts 163 is the same as that of the holding parts 161 and they are connected to a plurality of holding parts 161. However, in FIG. 9, the elevating parts 163 are schematically shown by one block for simplification of illustration. It was.

Further, the raising and lowering of the holding portion 161 by the raising and lowering portion 163 is performed during the vacuum drying process as described later, but may also be performed during the loading and unloading of the substrate G. That is, for example, when the substrate G is carried from the substrate transport region CR8 (see FIG. 4) into the vacuum drying apparatus 123c, the elevating portion 163 first holds a part of a plurality of holding portions 161 (for example, the central portion of the substrate G). The holding portions 161) on both sides of the holding portion 161 are lowered.

Then, the fork portion (not shown) of the substrate transport device on which the substrate G is placed is inserted into the space above the lowered holding portion 161, and then the fork portion is lowered, so that the substrate G is lowered. It will be placed on the holding portion 161 that is not used. Next, when the fork portion is pulled out and the holding portion 161 that has been lowered by the elevating portion 163 is raised to the original position, the substrate G is held by the holding portion 161 as shown in FIG.

The depressurizing mechanism 170 is connected to the chamber 150 and decompresses the internal atmosphere of the chamber 150 to, for example, 1 Pa or less. As the decompression mechanism 170, for example, a vacuum pump such as a dry pump, a mechanical booster pump, or a turbo molecular pump can be used.

The inspection device 200 includes a first imaging unit 210a, a second imaging unit 210b, and a third imaging unit 210c. The number of imaging units is merely an example and is not limited, and may be 2 or less or 4 or more.

The first to third imaging units 210a to 210c are arranged outside the chamber 150 in the vicinity of the window portion 152. Specifically, the first and third imaging units 210a and 210c are arranged in the vicinity of the window portion 152 located above the peripheral edge of the substrate G, and the second imaging unit 210b is located above the central portion of the substrate G. It is arranged in the vicinity of the positioned window portion 152.

Hereinafter, the first imaging unit 210a will be described as an example, but since the first to third imaging units 210a to 210c have almost the same configuration, the following description will also be given to the second and third imaging units 210b and 210c. It is valid. In FIGS. 8 and 9, with respect to the components of the second and third imaging units 210b and 210c, the same components as those of the first imaging unit 210a are designated by the same numbers with only the last alphabet changed. The explanation will be omitted.

The first image pickup unit 210a includes an image pickup unit 11a, an illumination unit 12a, and a focus adjustment unit 13a. The image pickup unit 11a is located above the window portion 152 and images the substrate G. Specifically, the coating region (described later) on which the organic material is applied on the substrate G is imaged through the window portion 152. By providing the chamber 150 with the window portion 152 for imaging in this way, the substrate G in the chamber 150 can be imaged from the outside of the chamber 150, although the configuration is simple.

Further, the imaging unit 11a is arranged so that the optical axis of the imaging unit 11a is perpendicular to the main surface of the substrate G. As the image pickup unit 11a, for example, a CCD (Charge Coupled Device) image sensor camera having a long focus lens can be used, but the imaging unit 11a is not limited to this.

The illumination unit 12a has a light source (not shown) and is attached to the side surface of the image pickup unit 11a. The illumination unit 12a irradiates the substrate G with light for imaging from such a light source. Specifically, the image pickup unit 11a includes a half mirror (not shown) that reflects light from the illumination unit 12a attached to the side surface downward. Then, the light from the illumination unit 12a reflected by the half mirror is incident on the direction perpendicular to the main surface of the substrate G, in other words, in the direction coaxial with the optical axis of the image pickup unit 11a, and becomes an image pickup object. The application area is irradiated. As described above, the illumination unit 12a is a so-called coaxial illumination, but the present invention is not limited to this, and for example, the coating region of the substrate G may be irradiated with light from an oblique direction.

The focus adjusting unit 13a includes a main body unit 14a and a slide unit 15a. The main body portion 14a is fixed to the ceiling portion 150a of the chamber 150. Further, a drive source (not shown) for driving the slide portion 15a is housed inside the main body portion 14a. As such a drive source, for example, an electric motor can be used.

The slide portion 15a is attached to the main body portion 14a so that the base end portion can slide in a direction (Z-axis direction) perpendicular to the main surface of the substrate G. Further, the imaging unit 11a is fixed to the tip of the slide unit 15a.

A control device 140 (see FIG. 4) is connected to the focus adjusting unit 13a configured as described above via a cable (not shown). Then, the control device 140 controls the drive source of the main body portion 14a to slide the slide portion 15a and the imaging unit 11a in a direction perpendicular to the main surface of the substrate G, thereby focusing the imaging unit 11a. It can be adjusted as appropriate.

As described above, the first to third imaging units 210a to 210c have substantially the same configuration. Therefore, in the following, when the first to third imaging units 210a to 210c are not particularly distinguished for the imaging unit 11a and the lighting unit 12a, the alphabets at the end are omitted and described as "imaging unit 11" and "illuminating unit 12". I have something to do.

The image pickup unit 11, the illumination unit 12, the elevating unit 163, and the decompression mechanism 170 are also connected to the control device 140 (see FIG. 4) via a cable (not shown), and their operations are controlled.

<4. Control device configuration>
The configuration of the control device 140 will be described in detail with reference to FIG. FIG. 10 is a block diagram of the control device 140. Note that, in FIG. 10, the components necessary for explaining the features of the inspection device 200 and the vacuum drying device 123c according to the embodiment are represented by functional blocks, and the description of general components is omitted. ..

In other words, each component shown in FIG. 10 is a functional concept and does not necessarily have to be physically configured as shown. For example, the specific form of distribution / integration of each functional block is not limited to the one shown in the figure, and all or part of it is functionally or physically distributed in arbitrary units according to various loads and usage conditions. -It is possible to integrate and configure.

Further, each processing function performed in each functional block is realized by a processor such as a CPU and a program analyzed and executed by the processor, or as hardware by wired logic. It can be realized.

First, as already described, the control device 140 includes a control unit 141 and a storage unit 142. The control unit 141 functions as, for example, the functional blocks 141a to 141h shown in FIG. 10 by reading and executing the program stored in the storage unit 142. Subsequently, the functional blocks 141a to 141h will be described.

As shown in FIG. 10, the control unit 141 includes a lighting control unit 141a, an imaging control unit 141b, an image acquisition unit 141c, a color density measurement unit 141d, a determination unit 141e, a dry state detection unit 141f, and decompression. A control unit 141g and an elevating control unit 141h are provided. Further, the storage unit 142 stores, for example, captured image information 142a, pattern / position information 142b, predetermined range information 142c, and dry state information 142d.

The illumination control unit 141a controls the illumination unit 12 to irradiate the light from the illumination unit 12 toward the substrate G. The image pickup control unit 141b controls the image pickup unit 11 to cause the image pickup unit 11 to take an image of the substrate G being dried under reduced pressure.

The image acquisition unit 141c acquires an image captured by the image capturing unit 11 and stores it in the storage unit 142 as captured image information 142a. FIG. 11 is an example of the captured image 20 captured by the imaging unit 11, and is a schematic enlarged view showing a part of the captured image 20 in an enlarged manner.

As shown in FIG. 11, the imaging unit 11 images the peripheral regions of the bank 540 and the bank 540 of the substrate G. Although only one bank 540 is shown in FIG. 11, the imaging unit 11 may image a plurality of banks 540.

Further, in the example shown in FIG. 11, among the light emitting layers 533 formed on the substrate G, the captured image 20 obtained by capturing the G color light emitting layer 533G (see FIGS. 7A and 7B) is shown. That is, FIG. 11 shows the captured image 20 captured by the imaging unit 11 provided in the vacuum drying device 123c of the light emitting layer forming block 123. In the following, the coating region 21 in which the G color light emitting layer 533G is formed will be described as an example, but the following description is also valid for the coating region 21 in which the R color light emitting layer 533R and the B color light emitting layer 533B are formed. To do.

As described above, the organic solvent forming the G color light emitting layer 533G is applied to the inside of the bank 540, and the region to which the organic material is applied is designated as the “coating region 21” in FIG. Shown in. In this way, the imaging unit 11 images the coating region 21 of the substrate G.

Returning to the description of FIG. 10, the color density measuring unit 141d reads the captured image information 142a from the storage unit 142 and measures the color density of the coating region 21 imaged by the imaging unit 11. Here, the color density is expressed by quantifying the imaged coating region 21 into 0 to 255 gradations for each of the three primary colors of red, green, and blue.

In the present embodiment, each of the three primary colors of red, green, and blue is quantified into 0 to 255 gradations (8 bits) and expressed as the color density, but the gradation of each of the three primary colors is imaged. Depending on the performance of the sensor camera, it can be quantified into 65536 gradations (16 bits) or higher and used as the color density.

When the imaging unit 11 images a plurality of banks 540 and there are a plurality of coating regions 21 on which the G color light emitting layer 533G is formed, the color density measuring unit 141d may, for example, average the color densities of the plurality of coating regions 21. The value may be measured. As the above-mentioned average value, various average values such as a simple average and a weighted average can be applied. Further, when there are a plurality of coating regions 21 on which the G color light emitting layer 533G is formed, the color density measuring unit 141d is not limited to the above-mentioned example of measuring the average value, and is represented, for example, from among the plurality of coating regions 21. One coating region 21 may be selected and the color density of the coating region 21 may be measured.

In addition to measuring the color density, the color density measurement unit 141d also performs pattern search processing and position information acquisition processing. The pattern search process is a process of searching which pattern of the patterns formed on the substrate G matches the shape of the pattern of the bank 540 having the imaged coating region 21. Further, the position information acquisition process is a process of acquiring position information on the substrate G of a pattern that is determined to match by the search process.

Specifically, the storage unit 142 has a pattern shape of the bank 540 (hereinafter referred to as “storage pattern shape”) in the substrate G to be subjected to the vacuum drying treatment, a type of the organic EL layer 530 formed in the bank 540, and the bank 540. The position information and the like are stored in advance as the pattern / position information 142b.

The type of information of the organic EL layer 530 stored above is, for example, information such as the hole injection layer 531 and the hole transport layer 532 and the light emitting layer 533. Further, the information on the type of the organic EL layer 530 also includes information on which of the R color light emitting layer 533R, the G color light emitting layer 533G, and the B color light emitting layer 533B, in the case of the light emitting layer 533. Further, the position information of the bank 540 is, for example, XY coordinates indicating the relative position of the bank 540 with respect to the reference point (origin) set on the substrate G, but the position information is not limited to this.

In the pattern search process, the color density measuring unit 141d compares the pattern shape of the bank 540 having the imaged coating region 21 with the storage pattern shape, and searches for a matching storage pattern shape. Then, the color density measurement unit 141d associates the information on the type and position of the organic EL layer 530 of the bank 540 having the matching storage pattern shape by the search with the information indicating the color density measured above, and obtains such information. Is output to the determination unit 141e.

The determination unit 141e calculates a value indicating a change in the color density of the coating region 21, specifically, a rate of change in the color density, based on the information output from the color density measurement unit 141d. The determination unit 141e described above calculates the rate of change as a value indicating a change in color density, but the change rate is not limited to this, and may be other values such as the amount of change in color density. May be good.

Here, the relationship between the change in color density during the vacuum drying process and the dried state of the coating region 21 of the substrate G will be described with reference to FIG. FIG. 12 is a graph showing the color density measured by the color density measuring unit 141d during the vacuum drying process.

In FIG. 12, in order from the top, the broken line graph is "red density 30R", the one-dot chain line graph is "green density 30G", and the two-dot chain line graph is "blue density 30B". Further, in FIG. 12, the solid line graph is the pressure value 31 in the chamber 150. In the example shown in FIG. 12, the color density measurement was started after the time T0 had elapsed since the vacuum drying process was started.

When the color density of the coated region 21 during the vacuum drying process was measured, the inventors found that there was a correlation between the color density of the coated region 21 and the dry state of the coated region 21. .. Specifically, for example, as shown in FIG. 12, when the vacuum drying process is started and the time Ta elapses, the pressure value 31 does not change, and the chamber 150 is maintained in a state of being depressurized to a predetermined pressure. To.

In the coating region 21, when the drying has just started before the pressure is reduced to a predetermined pressure, the color density changes relatively significantly, but after the time Ta has passed, in other words, with the passage of time. As the drying is completed, the color density gradually stabilizes. Then, for example, at a green density of 30 G, the value stabilizes at time Tb, and the coating region 21 is in a state of being completely dried.

This is because the amount of the solvent removed by vacuum drying in the coating region 21 gradually decreases with the passage of time, and the change in color density disappears. As described above, it can be seen that there is a correlation between the color density of the coating region 21 and the dry state of the coating region 21.

Therefore, in the vacuum drying device 123c provided with the inspection device 200 according to the present embodiment, the rate of change in the color density of the coating area 21 is calculated, and the dry state of the coating area 21 is detected based on the calculated rate of change. I made it.

Specifically, the determination unit 141e shown in FIG. 10 calculates the rate of change in color density and determines whether or not the calculated rate of change in color density is within a predetermined range, in other words, color. It is determined whether or not there is no change in the concentration and the value becomes stable. The above-mentioned predetermined range is set in advance to a value that can be determined to be stable because the change in color density with the progress of drying becomes relatively small, and is stored in the storage unit 142 as the predetermined range information 142c. The determination unit 141e outputs the determination result to the dry state detection unit 141f.

The dry state detection unit 141f detects the dry state of the coating region 21 based on the determination result. Specifically, the dry state of the coating region 21 is detected based on the color density of the coating region 21 imaged by the imaging unit 11. .. More specifically, the dry state detection unit 141f detects that the coating region 21 is in a dry state when it is determined that the rate of change calculated by the determination unit 141e is within a predetermined range.

The dry state detection unit 141f sets the time from the start of the vacuum drying process until the detection of the dry state (here, for example, time Tb) is set as the "drying time", and sets the drying time. It is stored in the storage unit 142 as the dry state information 142d.

In addition to the above-mentioned drying time, the dry state detection unit 141f also stores the type and position information of the organic EL layer 530 of the bank 540 in which the dry coating region 21 is formed as the dry state information 142d. Store in part 142.

As described above, the dry state detection unit 141f uses the color density of the coating region 21 to detect the dry state of the coating region 21 earlier than the technique of producing many samples. be able to.

Further, as described above, the vacuum drying device 123c is provided with an inspection device 200 for detecting the dry state of the coating area 21, and the drying time is set based on the detected drying state of the coating area 21. As a result, for example, when the work of setting the optimum drying time before mass-producing the organic light emitting diode 500 is performed, it is not necessary to prepare many samples, and the efficiency of the setting work can be improved.

The dry state detecting unit 141f does not need to detect the dry state of the coating region 21 for all the color densities measured by the color density measuring unit 141d. That is, the dry state detection unit 141f may select, for example, at least one color density from the red density, the green density, and the blue density according to the type of the coating region 21.

More specifically, the color density includes red density, green density and blue density as described above. The method of changing the three color densities with the passage of time differs depending on the type of the coating region 21, and these changes in the color densities also correspond to the changes with the progress of the dry state.

Therefore, the color density at which the change with the progress of the dry state appears remarkably is obtained in advance through experiments or the like, and the dry state detection unit 141f selects the red density, the green density, and the blue density according to the type of the coating region 21. At least one color density may be selected.

Then, the dry state detection unit 141f may detect the dry state based on the selected color density. As described above, the dry state detection unit 141f can accurately detect the dry state of the coating region 21 by using a color density at which a change easily appears as the dry state progresses. The number of color densities selected by the dry state detection unit 141f can be set to any value.

Continuing the description of FIG. 10, the decompression control unit 141g controls the decompression mechanism 170 to perform the decompression drying process. Specifically, after the drying time setting work is completed, the decompression control unit 141g performs the decompression drying treatment for a set drying time or a time obtained by adding a predetermined time to the set drying time.

The elevating control unit 141h controls the elevating unit 163 and elevates the holding unit 161. The elevating control unit 141h puts the coating region 21 in a dry state during the vacuum drying process performed after the drying time setting work is completed, in other words, during the vacuum drying process performed when the organic light emitting diode 500 is mass-produced. The elevating unit 163 is controlled accordingly, which will be described later with reference to FIG.

<5. Specific operation of inspection device and vacuum drying device>
Next, the content of the process executed by the vacuum drying device 123c provided with the inspection device 200 according to the present embodiment will be described with reference to FIG.

FIG. 13 is a flowchart showing a processing procedure of a process of setting a drying time in the vacuum drying device 123c provided with the inspection device 200 according to the present embodiment. Note that FIG. 13 shows, for example, a processing procedure for setting an optimum drying time before mass-producing the organic light emitting diode 500. Therefore, in the example shown in FIG. 13, the dry state of the coating region 21 is continuously detected for a preset detection processing time, and the drying time is set after the detection processing time has elapsed. The above-mentioned detection processing time is set to a time sufficiently longer than the time expected that the coating region 21 becomes dry.

Further, each processing procedure shown in FIG. 13 is executed according to the control of the control unit 141 of the control device 140.

More specifically, as shown in FIG. 13, the image pickup control unit 141b of the control unit 141 images the coating region 21 coated with the organic material on the substrate G (step S10). Before the imaging process, it is assumed that the light from the illumination unit 12 is directed toward the substrate G.

Next, the color density measuring unit 141d compares the shape of the pattern of the bank 540 having the coating region 21 with the storage pattern shape in the captured image, and searches for a matching storage pattern shape (step S11). Subsequently, the color density measuring unit 141d acquires the type and position information of the organic EL layer 530 of the bank 540 having the matching storage pattern shape by the search process (step S12).

Next, the color density measuring unit 141d measures the color density of the coating region 21 in the captured image (step S13). Subsequently, the determination unit 141e calculates the rate of change in the color density of the coating region 21 (step S14), and determines whether or not the calculated rate of change in the color density is within a predetermined range (step S15).

When the determination unit 141e determines that the rate of change in color density is within the predetermined range (steps S15, Yes), it is determined that the rate of change in color density is within the predetermined range after the vacuum drying process is started. The time until the product is dried is calculated as the “drying time” (step S16).

When the determination unit 141e determines that the rate of change in color density is not within the predetermined range (steps S15, No), that is, when it determines that the color density has changed relatively significantly, step S16. Skip the processing of.

Next, the dry state detection unit 141f detects that the coating region 21 has become dry when, for example, the determination unit 141e determines that the rate of change is within a predetermined range, and the dry state detection unit 141f becomes dry. Information indicating that is output and stored in the storage unit 142 (step S17). Further, the dry state detection unit 141f determines the dry state of the acquired organic EL layer 530 of the bank 540, the position information, the measured color density of the coating region 21, and the like, regardless of the determination result of the determination unit 141e. It is output as the information to be shown and stored in the storage unit 142.

Subsequently, the dry state detection unit 141f determines whether or not the above-mentioned detection processing time has elapsed (step S18). When the dry state detection unit 141f determines that the detection processing time has not elapsed (steps S18, No), the processing of steps S10 to S17 is repeated.

On the other hand, when the drying state detection unit 141f determines that the detection processing time has elapsed (steps S18, Yes), the drying state detection unit 141f sets the drying time (step S19). The drying time set here is the same value as the drying time calculated in step S16.

In this way, for example, before mass production of the organic light emitting diode 500, a series of processes for setting the optimum drying time is completed. Although not shown, for example, in the case of mass-producing the organic light emitting diode 500, in the vacuum drying device 123c, the drying time set in step S19 or the time obtained by adding a predetermined time to the set drying time It is configured to perform a vacuum drying process over a period of time. In the above, the reason why the predetermined time is added to the drying time is that, for example, even if the drying progress of the coating region 21 is delayed due to the environmental conditions, the delayed time is absorbed by the predetermined time and the coating is applied. This is to ensure that the drying of the region 21 is completed.

Further, in the vacuum drying device 123c described above, the drying state of the coating region 21 is detected at the time of the work of setting the drying time. However, in the vacuum drying apparatus 123c, the detection of the dried state of the coating region 21 is not limited to the above.

That is, for example, the drying state of the coating region 21 may be detected by the vacuum drying device 123c after the drying time is set. For example, as will be described later, in the coating region 21 of the substrate G, the drying speed is different between the peripheral portion and the central portion of the substrate G. Therefore, in the present embodiment, the dry state of the coating region 21 in the peripheral portion and the coating region 21 in the central portion is detected, and the substrate G is moved up and down based on the detection result to promote the drying. Good.

This will be described with reference to FIG. FIG. 14 is a graph showing the G color density of the coating region 21 in the peripheral portion and the coating region 21 in the central portion. In FIG. 14, the G color density of the coating region 21 imaged by the imaging unit 11a of the first imaging unit 210a is designated by reference numeral 41. Further, in FIG. 14, a reference numeral 42 is attached to the G color density of the coating region 21 imaged by the imaging unit 11b of the second imaging unit 210b, and the coating region 21 imaged by the imaging unit 11c of the third imaging unit 210c is attached. The G color density of No. 43 is designated by reference numeral 43. That is, the G color densities 41 and 43 are the G color densities of the coating region 21 in the peripheral portion, and the G color densities 42 are the G color densities of the coating region 21 in the central portion.

As shown in FIG. 14, in all of the G color densities 41 to 43, after the vacuum drying treatment is started and the time T0 elapses, the G color density increases sharply and then decreases. Then, among the three G color densities 41 to 43, in the G color densities 41 and 43, the value that had decreased at time T1 is reversed and increased, and in the G color density 42 At time T2, which is later than time T1, the decreasing value is reversed and increased.

In this inversion, as shown in FIG. 7A, the light emitting layer 533, which had been raised above the upper surface of the bank 540, was lowered by drying and was lowered below the upper surface of the bank 540 (see FIG. 7B). This is an occasional event. The coating area 21 immediately after the state shown in FIG. 7B is not in a completely dry state.

As described above, the timing of inversion at the G color densities 41 to 43 is such that the G color density 42 of the coating region 21 in the central portion is later than the G color densities 41 and 43 of the coating region 21 in the peripheral portion. That is, it can be seen that the coating region 21 in the central portion has a slower drying rate than the coating region 21 in the peripheral portion and is difficult to dry.

Further, in the chamber 150, an air flow is generated by the decompression mechanism 170, but depending on the direction of the air flow and the like, there may be a place in the chamber 150 where the coating region 21 is likely to dry.

Therefore, in the vacuum drying device 123c according to the present embodiment, for example, the elevating portion 163 may be controlled to elevate the holding portion 161 according to the drying state of the coating region 21, and the height of the substrate G may be adjusted. Good.

Specifically, the elevating control unit 141h controls the elevating unit 163 to elevate the holding unit 161 when the G color densities 41 and 43 of the coating area 21 in the peripheral portion are reversed, and the coating area 21 in the central portion is the chamber. The height of the substrate G is adjusted so that it is located in a place within 150 where it is easy to dry. Thereby, drying in the coating region 21 in the central portion can be promoted.

Further, by configuring as described above, the drying speed of the coating region 21 in the central portion can be brought close to the drying speed of the coating region 21 in the peripheral portion, and thus uneven drying may occur depending on the location in the substrate G. It can be suppressed.

As described above, the inspection device 200 according to the first embodiment includes an imaging unit 11 and a dry state detection unit 141f. The imaging unit 11 images the coating region 21 on which the organic material is coated on the substrate G. The dry state detection unit 141f detects the dry state of the coating region 21 based on the color density of the coating region 21 imaged by the imaging unit 11. As a result, the dry state of the coating region 21 coated with the organic material on the substrate G can be detected at an early stage.

In the above description, the dry state detection unit 141f detects the dry state of the coating region 21 based on the color density of one portion of the coating region 21, but the present invention is not limited to this. That is, the dry state detection unit 141f may detect the dry state based on the color density of a plurality of points 22 in the coating region 21, for example, as shown by an imaginary line in FIG.

As a result, the dry state detection unit 141f can compare the color densities at a plurality of points 22 in the coating region 21, and confirm whether the drying is uniform in the coating region 21. You can also.

Further, since the difference in color density at a plurality of points 22 in the coating region 21 can be calculated, the film thickness distribution in the coating region 21 can be estimated from such a difference, and as a result, the film thickness of the coating region 21 with respect to the dry state can be estimated. It is also possible to analyze the changes in.

(Second Embodiment)
Next, the vacuum drying device 123c provided with the inspection device 200 according to the second embodiment will be described. In the following description, the same parts as those already described will be designated by the same reference numerals as those already described, and duplicate description will be omitted.

In the second embodiment, the arrangement of the imaging unit is changed. FIG. 15 is a schematic enlarged cross-sectional view showing the vicinity of the image pickup unit 311 of the image pickup unit 310 according to the second embodiment.

As shown in FIG. 15, in the second embodiment, the imaging unit 311 is arranged so that the optical axis of the imaging unit 311 is oblique to the main surface of the substrate G. As the illumination unit 312 of the image pickup unit 310, a coaxial illumination unit can be used as in the first embodiment.

Further, the image pickup unit 310 may further include an auxiliary illumination unit 320. The auxiliary illumination unit 320 is arranged above the coating area 21 which is an image pickup object, and irradiates the substrate G with light for imaging. In FIG. 15, for convenience of understanding, the coating area 21 is schematically shown by a broken line closed curve.

In the second embodiment, by arranging the imaging unit 311 as described above, the dry state of the coating region 21 can be detected at an early stage as in the first embodiment. Further, in the second embodiment, by configuring the imaging unit 311 as described above, the coating region 21 can be imaged from diagonally above. Since the color density of the coating region 21 imaged from diagonally above may show a relatively large change as the drying progresses, in the second embodiment, the dry state of the coating region 21 can be detected more accurately. It will be possible.

Further, in the second embodiment, the volume of the coating region 21 imaged from diagonally above may be obtained, and the fluctuation of the volume of the coating region 21 with respect to the dry state may be analyzed.

(Third Embodiment)
Next, the vacuum drying device 123c provided with the inspection device 200 according to the third embodiment will be described. In the third embodiment, as shown by an imaginary line in FIG. 9, a polarizing filter 400 is provided. As a result, the color density of the coating region 21 can be measured more accurately, and as a result, an accurate drying state can be detected.

To be described in detail below, the polarizing filter 400 is arranged between the imaging unit 11 and the coating region 21 (see FIG. 11) of the substrate G. Note that FIG. 9 shows only the polarizing filter 400 arranged between the imaging unit 11a and the coating region 21 for simplification of the illustration, and is arranged between the imaging units 11b and 11c and the coating region 21. The illustration of the polarizing filter 400 is omitted.

By the way, the light of the illumination unit 12 is applied to the coating region 21 and reflected in the coating region 21. The light reflected from the coating region 21 is "internally reflected light" that reaches the inside of the coating region 21 and is reflected on the upper surface of the substrate G, and diffusely reflected on the surface of the coating region 21 without reaching the inside of the coating region 21. "Surface reflected light" is included. Since the diffusely reflected surface reflected light causes disturbance for the image pickup unit 11, it is preferable not to receive the light as much as possible.

Therefore, in the polarizing filter 400, the central portion through which the optical axis of the imaging unit 11 passes passes the light having the phase of the internally reflected light described above, and the peripheral portion surrounding the central portion is orthogonal to the direction of polarization. The light having the phase of the diffusely reflected surface reflected light is prevented from passing through.

As a result, in the imaging unit 11, the light reception of the diffusely reflected surface reflected light can be reduced by the polarizing filter 400, and the influence of the surface reflected light can be suppressed. Therefore, in the third embodiment, the color density of the coating region 21 can be measured more accurately, and as a result, an accurate drying state can be detected.

(First modification)
Next, the vacuum drying device 123c provided with the inspection device 200 according to the first modification will be described.

The vacuum drying device 123c according to the first modification includes a notification unit 410 as shown by an imaginary line in FIG. Then, in the vacuum drying device 123c, if the drying state detection unit 141f deviates from the predetermined range after the rate of change in color density has converged within the predetermined range, there is a possibility that some abnormality has occurred in the vacuum drying device 123c. It is estimated that there is, and the user is notified via the notification unit 410.

A display, a buzzer, or the like can be used as the notification unit 410, and when it is estimated that some abnormality has occurred in the vacuum drying device 123c, for example, a display display indicating the occurrence of the abnormality or a buzzer sounding is performed. This makes it possible for the user to recognize the abnormality of the vacuum drying device 123c at an early stage.

Further, the vacuum drying device 123c according to the first modification may be provided with an optical measuring device 420 as shown by an imaginary line in FIG. The light measuring device 420 is provided in the illuminating unit 12 and measures the amount of light in the illuminating unit 12.

Information indicating the amount of light measured by the light measuring device 420 is output to the lighting control unit 141a. When, for example, the amount of light of the lighting unit 12 decreases and the deterioration of the lighting unit 12 is detected, the lighting control unit 141a notifies the user via the notification unit 410.

As a result, for example, it is possible to urge the user to maintain the lighting unit 12 before the color density of the coating region 21 cannot be accurately measured due to aged deterioration of the lighting unit 12. That is, it is possible to prevent in advance that the color density of the coating region 21 cannot be accurately measured due to the aged deterioration of the lighting unit 12 and the accuracy of detecting the dry state of the coating region 21 is lowered. ..

(Second modification)
Next, a second modification will be described. In the vacuum drying apparatus 123c according to the second modification, the wavelength of the light emitted from the illumination unit 12 to the coating region 21 is changed according to the type of color density to be measured.

Specifically, the value of the color density of the coating region 21 measured by the color density measuring unit 141d may change depending on the wavelength of the light emitted from the illuminating unit 12. Therefore, in the second modification, the illumination control unit 141a selects and selects a wavelength at which a change in color density is likely to appear as the dry state progresses, according to the type of color density of the coating region 21 to be measured. The coating region 21 is irradiated with light having a wavelength. It is assumed that the wavelength selected by the lighting control unit 141a is stored in the storage unit 142 or the like by deriving an appropriate value in advance by, for example, an experiment or the like.

As a result, the dry state detection unit 141f can accurately capture the change in color density as the dry state progresses, and as a result, the dry state of the coating region 21 can be accurately detected. Further, by changing the wavelength of light as described above, it is possible to reduce damage to the applied ink and to acquire a captured image that is easier to observe.

(Third variant)
Next, a third modification will be described. In the vacuum drying device 123c according to the third modification, the image pickup unit 11 is provided with an infrared image sensor camera having a long focus lens made of a material having a relatively high infrared transmittance. Further, in such a case, the window portion 152 is also made of a material having a relatively high infrared transmittance.

In the third modification, the intensity of infrared rays radiated from the coating region 21 of the substrate G to be measured is measured by an infrared image sensor camera (thermoviewer camera or the like), and the temperature distribution of the coating region 21 is determined. You can observe the temperature image. Further, by using such an infrared image sensor camera (thermoviewer camera or the like), temperature measurement can be performed at high speed and without contact.

Then, if the measured temperature of the coating region 21 is stored in the storage unit 142 as the dry state information 142d, it is possible to analyze the temperature change of the coating region 21 with respect to the dry state of the coating region 21.

The configurations described in the first to third embodiments and the first to third modifications described above can be combined as appropriate. That is, for example, the configuration of the first embodiment is combined with the notification unit 410 of the first modification and the illumination control unit 141a for changing the wavelength of light of the illumination unit 12 of the second modification. May be good.

Further, in the above, the ceiling portion 150a of the chamber 150 has a rectangular shape in a plan view, and the window portion 152 and the first to third imaging units 210a to 210c are arranged along the diagonal line of the ceiling portion 150a. However, it is not limited to this. That is, for example, the window portion 152 and the first to third imaging units 210a to 210c may be arranged along the X-axis direction and the Y-axis direction with respect to the ceiling portion 150a.

Further, with the above configuration, the captured image information 142a includes a continuous captured image showing the process in which the coating region 21 is dried. As a result, for example, when setting a drying recipe for the vacuum drying process of the vacuum drying devices 121c, 122c, 123c, it is possible to efficiently optimize by analyzing continuous captured images.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

11,311 Imaging unit 12,312 Lighting unit 21 Coating area 100 Substrate processing system 121c, 122c, 123c Decompression drying device 140 Control device 141 Control unit 141a Lighting control unit 141b Imaging control unit 141c Image acquisition unit 141d Color density measurement unit 141e Judgment Unit 141f Dry state detection unit 141g Decompression control unit 141h Elevating control unit 160 Board holding mechanism 161 Holding unit 163 Elevating unit 170 Decompression mechanism 200 Inspection device 400 Polarizing filter G Substrate

Claims (3)

An imaging unit that captures an image of a coating area coated with an organic material on a substrate,
An inspection apparatus including a dry state detection unit that detects a dry state of the coating region based on the color density of the coating region imaged by the imaging unit. The inspection device according to claim 1 and
The chamber in which the substrate is housed and
A vacuum drying device including a decompression mechanism for depressurizing the inside of the chamber. An imaging process that images the coated area where the organic material is applied on the substrate,
A dry state detection step of detecting a dry state of the coating region based on the color density of the coating region imaged in the imaging step,
A vacuum drying apparatus including a drying time setting step of setting a drying time for drying by depressurizing the inside of a chamber in which the substrate is housed based on the drying state detected in the drying state detecting step. Control method.

Images