CN109562407B

CN109562407B - Film forming apparatus and film forming method

Info

Publication number: CN109562407B
Application number: CN201780042983.7A
Authority: CN
Inventors: 冈本裕司
Original assignee: Sumitomo Heavy Industries Ltd
Current assignee: Sumitomo Heavy Industries Ltd
Priority date: 2016-08-22
Filing date: 2017-08-09
Publication date: 2021-09-28
Anticipated expiration: 2037-08-09
Also published as: WO2018037921A1; CN109562407A; JP2018030046A; KR20190043524A; JP6689540B2; TW201822895A; KR102278409B1; TWI655031B

Abstract

The invention provides a film forming apparatus and a film forming method capable of suppressing the deviation of the shape of the formed film. The film forming section applies a film material to the substrate to form a film. The imaging device images the surface of the substrate disposed on the film forming section. The control section controls the film forming section. The control unit stores pattern data defined in accordance with the planar shape of the film to be formed. Before forming a film based on the pattern data, the control section discharges the film material to form an evaluation pattern in a part of the inside of a region where the film material is applied for forming the film. The quality of the surface state of the substrate is determined based on an image obtained by imaging the evaluation pattern with an imaging device, and different processing is executed based on the determination result.

Description

Film forming apparatus and film forming method

Technical Field

The present invention relates to a film forming apparatus and a film forming method.

Background

In forming a resist pattern for patterning a transparent conductive film of a touch panel, photolithography or screen printing is being used. In the method using the photolithography technique, a high-definition pattern can be formed, but the apparatus cost, the waste liquid treatment cost, and the like become high. The method using the screen printing technique is more advantageous than the method using the photolithography technique in terms of the apparatus cost and the waste liquid disposal cost, but it is difficult to form a high-definition pattern. A technique for forming a resist pattern by an inkjet printing technique has been proposed (patent document 1).

Prior art documents

Patent document

Patent document 1: international publication No. 2013/089049

Disclosure of Invention

Technical problem to be solved by the invention

It is known that when films having the same pattern are formed on a plurality of substrates by the inkjet printing technique, the shapes of the films vary among the substrates. The invention aims to provide a film forming apparatus and a film forming method capable of suppressing the deviation of the shape of the formed film.

Means for solving the technical problem

According to an aspect of the present invention, there is provided a film forming apparatus including:

a film forming section for forming a film by applying a film material to a substrate;

an imaging device for imaging a surface of the substrate disposed on the film forming section; and

a control section for controlling the film forming section,

the control part stores pattern data defined corresponding to the planar shape of the formed film,

before forming a film based on the pattern data, the control section controls the film forming section to form an evaluation pattern made of the same material as a film to be formed in a part of the inside of a region where a film material is applied to form the film,

the control unit acquires an image obtained by imaging the evaluation pattern by the imaging device,

the control section determines whether or not the surface state of the substrate is good according to a determination condition whether or not a bleeding width around the evaluation pattern is within an allowable range based on the acquired image, and performs different processing based on a determination result.

According to another aspect of the present invention, there is provided a film forming method, wherein,

an evaluation pattern is formed by discharging a film material of a film having a certain pattern from an ink jet head to the inside of a region of a substrate surface where the film is to be formed,

determining whether the surface state of the substrate is good or bad based on the evaluation pattern formed on the substrate,

forming the film having the certain pattern on the surface of the substrate when the determination result is good,

and when the determination result is bad, cleaning the surface of the substrate, and then forming the film having the certain pattern on the surface of the substrate.

Effects of the invention

By forming the evaluation pattern before forming the film and determining whether the surface state of the substrate is good or bad, it is possible to avoid the case where the film is formed on the substrate having a bad surface state directly. This can suppress variations in the shape of the formed film.

Drawings

FIG. 1 is a schematic front view of a film forming apparatus according to an embodiment.

Fig. 2 is a plan view of a resist film used as an etching mask when patterning a transparent electrode of a touch panel.

Fig. 3 is a flowchart of a film formation method according to an embodiment.

Fig. 4 is a plan view showing a positional relationship between a film to be formed and an evaluation pattern.

Fig. 5A is a plan view of a normal dot pattern formed from one droplet, fig. 5B is a plan view of a dot pattern larger than the normal dot pattern, fig. 5C is a plan view of a dot pattern which is oozed, and fig. 5D is a plan view of a dot pattern which is deformed in a planar shape.

Fig. 6A is a cross-sectional view of the substrate in a state where the evaluation pattern is formed on the substrate (step S4), fig. 6B is a cross-sectional view of the substrate in a state where the resist film is formed on the substrate (step S7), fig. 6C is a cross-sectional view of the substrate after etching the transparent conductive film using the resist film as an etching mask, and fig. 6D is a cross-sectional view of the substrate in a state where the resist film used as an etching mask is removed.

Fig. 7A and 7B are enlarged plan views of a part of a resist film to be formed.

Fig. 8A is a cross-sectional view of a substrate in a state where an evaluation pattern is formed on the substrate by a method according to another embodiment (step S4), and fig. 8B is a cross-sectional view of a substrate in a state where a resist film is formed on the substrate (step S7).

Detailed Description

A film forming apparatus and a film forming method according to an embodiment will be described with reference to fig. 1 to 7B.

FIG. 1 is a schematic front view of a film forming apparatus according to the present embodiment. A table 23 is supported on the base 20 via a moving mechanism 21. The table 23 functions as a support portion for supporting the substrate 50 on its upper surface (support surface). The moving mechanism 21 moves the table 23 in a two-dimensional direction parallel to the support surface, thereby moving the substrate 50 in the two-dimensional direction. As the movement mechanism 21 and the table 23, for example, an XY table can be used. Normally, the support surface of the table 23 is kept horizontal.

A plurality of inkjet heads 26 and a plurality of imaging devices 27 are arranged above a substrate 50 supported by a table 23. The inkjet head 26 and the imaging device 27 are supported by the base 20 via the gate frame 24. Each ink jet head 26 is provided with a plurality of nozzle holes. Droplets of the film material are discharged from the nozzle holes toward the substrate 50. The inkjet head 26, the stage 23, and the moving mechanism 21 function as a film forming section for forming a film on a substrate. The imaging device 27 images a part of the substrate 50 supported by the table 23, and transmits image data of the acquired two-dimensional image to the control device (control unit) 30.

The film can be formed by solidifying the liquid film material attached to the substrate 50. As the film material, a photocurable resin, a thermosetting resin, or the like can be used. A light source or a heat source for curing the film material attached to the substrate 50 is disposed on the side surface of the inkjet head 26.

The control device 30 controls the movement of the table 23 by the movement mechanism 21 and the ejection of the film material from the nozzle holes of the inkjet head 26. The control device 30 includes a storage device 31, and pattern data of a film to be formed is stored in the storage device 31. The pattern data is composed of a plurality of pixels (pixels) arranged in a matrix, for example. The control device 30 controls the movement mechanism 21 and the inkjet head 26 based on the pattern data, thereby forming a film having a desired pattern on the substrate 50.

Various commands and data are input from the input device 35 to the control device 30. The input device 35 uses, for example, a keyboard, a pointing device, a USB port, a communication device, and the like. The output device (output unit) 36 outputs various information related to the operation of the film forming apparatus based on a command from the control device 30. For example, a liquid crystal display, a speaker, a USB port, a communication device, or the like is used as the output device 36.

Fig. 2 is a top view of a resist film 53 used as an etching mask when patterning a transparent electrode film of a touch panel. The transparent electrode is formed by etching a transparent conductive film formed of ITO or the like using the resist film 53 as an etching mask. In fig. 2, the areas coated with resist are depicted with a dot pattern. In the film forming apparatus shown in fig. 1, a resist film 53 is formed on a substrate 50.

The resist film 53 includes a plurality of pad portions 51 arranged in a matrix and a connecting portion 52 connecting the plurality of pad portions 51 in the column direction. The interval G separating two pad portions 51 adjacent to each other in the row direction is the minimum size of the pattern.

Referring to fig. 3, a method of forming a film using the film forming apparatus shown in fig. 1 will be described.

Fig. 3 is a flowchart of a film formation method according to the present embodiment. First, in step S1, the substrate 50 (fig. 1) on which the film is to be formed is placed on the support surface of the table 23, and the substrate 50 is fixed by a vacuum chuck or the like. In step S2, control device 30 determines whether or not the alignment of substrate 50 is necessary. Whether or not alignment is necessary is determined by the type of the substrate 50, and information on whether or not alignment is necessary is stored in the storage device 31 (fig. 1).

For example, when an arbitrary pattern is formed on the substrate 50, it is necessary to align the formed pattern with a newly formed film. In this case, a new film is formed by positioning the alignment mark formed on the substrate 50. When no pattern is formed on the substrate 50, for example, when a film to be patterned is not formed on the entire surface of the substrate 50, alignment is not necessary. In this case, a new film is formed with reference to the stage coordinates defining the stage 23.

When the alignment of the substrate 50 is necessary, the position of the substrate 50 in the supporting surface of the table 23 is detected in step S3. Specifically, the alignment mark provided on the substrate 50 is imaged by the imaging device 27 (fig. 1) and the image is analyzed, thereby detecting the position of the substrate 50.

After the position of the substrate 50 is detected, in step S4, an evaluation pattern is formed inside the region where the film is to be formed. When the alignment of the substrate 50 is not required, step S4 is performed instead of step S3.

The processing of step S4 is explained with reference to fig. 4. Fig. 4 is a plan view showing a positional relationship between the resist film 53 to be formed and the evaluation pattern 55. The control device 30 determines at least one position where the evaluation pattern 55 should be formed based on the pattern data of the resist film 53 to be formed. The evaluation pattern 55 is disposed inside a region where a film material should be applied when the resist film 53 is formed based on the pattern data. For example, one evaluation pattern 55 is constituted by a plurality of dot patterns separated from each other. Fig. 4 shows an example in which the evaluation pattern 55 is formed of a 5-dot pattern disposed inside one pad portion 51. The size of one dot pattern included in the evaluation pattern 55 is a size formed by droplets discharged from one nozzle hole.

After determining the position at which the evaluation pattern 55 is to be formed, the control device 30 controls the inkjet head 26 and the moving mechanism 21 (fig. 1) to form the evaluation pattern 55 on the substrate 50.

After forming the evaluation pattern 55, in step S5 (fig. 3), the control device 30 moves the formed evaluation pattern 55 into the imaging range of the imaging device 27 and images the evaluation pattern 55. Then, in step S6, the quality of the surface state of the substrate 50 is determined based on the image of the evaluation pattern 55. Control device 30 executes different processing based on the determination result of the quality of the surface state.

A method of determining the quality of the surface state of the substrate 50 will be described with reference to fig. 5A to 5D. The liquid droplets landed on the surface of the substrate 50 spread in the in-plane direction, or bleed out or deform depending on the surface state. In the present embodiment, the quality of the surface state is determined based on the size, the bleeding width, the deformation of the shape, and the like of the formed evaluation pattern 55. For example, when the size, bleeding width, shape deformation, and the like of the formed evaluation pattern 55 are within a predetermined allowable range, the surface state is determined to be "good", and when the size, bleeding width, shape deformation, and the like are out of the allowable range, the surface state is determined to be "poor".

Fig. 5A is a plan view of a normal dot pattern 56 formed of one droplet. The planar shape of the normal dot pattern 56 is substantially a perfect circle.

Fig. 5B is a plan view showing an example in which one dot pattern 57 of the evaluation pattern 55 (fig. 4) is larger than the normal dot pattern 56. When the size of the large dot pattern 57 is out of the allowable range, the control device 30 determines that the surface state of the substrate 50 is defective. The size of the large dot pattern 57 can be represented by, for example, diameters in two directions orthogonal to each other.

Fig. 5C is a plan view showing an example in which a bleed-out 58b is generated in one dot pattern 58 of the evaluation pattern 55 (fig. 4). Bleeding 58b is observed around the body 58a of the dot pattern 58. For example, when the width (dimension in the radial direction) of the bleeding 58b is larger than the upper limit of the allowable range, the control device 30 determines that the surface state of the substrate 50 is defective.

Fig. 5D is a plan view showing an example of a planar shape deformation of one dot pattern 59 of the evaluation pattern 55 (fig. 4). For example, the dot pattern 59 expands in one direction (the left-right direction in fig. 5D) more than the normal dot pattern 56, but contracts in a direction (the up-down direction in fig. 5D) orthogonal thereto. When the amount of deformation of deformed dot pattern 59 is out of the allowable range, control device 30 determines that the surface state of substrate 50 is defective. As an index indicating the amount of deformation, a ratio of a long diameter to a short diameter, or the like can be used.

The allowable range is preferably set so as to satisfy the condition that the resist films 53 on both sides of the gap G corresponding to the minimum size of the pattern shown in fig. 2 do not contact each other, for example. As an example, the allowable range may be set so that the upper limit of the amount of projection of the formed dot pattern 57 (fig. 5B), dot pattern 58 (fig. 5C), and dot pattern 59 (fig. 5D) from the outer peripheral line of the normal dot pattern 56 is smaller than 1/2, which is the minimum size of the pattern.

In addition, dot patterns may be formed on a plurality of substrates whose surface states are known to be good in advance, and an allowable range may be set based on the variation in the size. For example, the upper limit of the allowable range may be a size obtained by adding 3 times the standard deviation to the average of the sizes of the formed dot patterns.

In the determination of the quality of the surface state of the substrate 50, the control device 30 performs the quality determination based on at least one determination condition of whether the size of the evaluation pattern 55 is within the allowable range, whether the bleeding width around the evaluation pattern 55 is within the allowable range, and whether the deformation of the planar shape is within the allowable range.

When the surface state of the substrate 50 is determined to be "good", the control device 30 forms the resist film 53 (fig. 2) on the substrate 50 based on the pattern data in step S7. After the resist film 53 is formed, the substrate 50 is carried out of the film forming apparatus in step S9.

When the surface state of the substrate 50 is determined to be "defective", the control device 30 outputs information indicating the surface state defect from the output device 36 in step S8. As an output method of the information, for example, an output by sound, an output by image, an output by light emission, or the like can be adopted.

Next, a method of forming a film on the substrate 50 and etching the transparent electrode film of the substrate 50 will be described with reference to fig. 6A to 6D. Fig. 6A to 6D are cross-sectional views corresponding to the position of one-dot broken line 6-6 in fig. 4.

Fig. 6A is a cross-sectional view of the substrate 50 in a state where the evaluation pattern 55 is formed on the substrate 50 (step S4 in fig. 3). The substrate 50 includes a glass substrate 50a and a transparent conductive film 50b made of ITO formed on the surface thereof. An evaluation pattern 55 made of a resist material is formed on the transparent conductive film 50 b. The evaluation pattern 55 is constituted by an isolated 5-dot pattern. Each dot pattern is formed by one droplet discharged from one nozzle hole of the inkjet head 26. Fig. 6A shows one arrow corresponding to the ejection of one droplet.

Fig. 6B is a cross-sectional view of the substrate 50 in a state where the resist film 53 is formed on the substrate 50 (step S7 in fig. 3). The controller 30 controls the moving mechanism 21 and the inkjet head 26 based on pattern data defined according to the shape of the formed resist film, thereby forming the resist film 53. Fig. 6B shows one arrow corresponding to the ejection of one droplet. Since the liquid droplets are applied so as to overlap each dot pattern forming the evaluation pattern 55, a bump 54 reflecting the shape of the evaluation pattern 55 is formed on the surface of the resist film 53.

As shown in fig. 6C, the transparent conductive film 50b is etched (patterned) using the resist film 53 as an etching mask. The transparent conductive film 50b in the region where the resist film 53 is not formed is removed by etching.

As shown in fig. 6D, the resist film 53 serving as an etching mask is removed. The transparent conductive film 50b remains in the region where the resist film 53 (fig. 6C) has been formed.

Next, the excellent effects of the above embodiment will be described with reference to fig. 7A and 7B.

Fig. 7A and 7B are enlarged plan views of a part of the resist film 53 to be formed. In fig. 7A and 7B, a target shape 53a of the resist film 53 to be formed is shown by a broken line.

Fig. 7A shows a plan view of the resist film 53 formed when the wettability of the surface of the substrate 50 is higher than a standard value. The resist film 53 formed is further expanded than the target shape 53 a. If the spread in the in-plane direction of the film material exceeds the allowable range, two pad portions 51 adjacent in the row direction of the formed resist film 53 are brought into contact with each other.

Fig. 7B is a plan view of the resist film 53 formed when the surface of the substrate 50 is in a state in which bleeding is likely to occur. A bleed 53b occurs around the target shape 53 a. Two pad portions 51 adjacent in the row direction are continued by the bleeding portion 53 b.

When the transparent conductive film 50B (fig. 6C) is etched in the state shown in fig. 7A and 7B, the transparent conductive film 50B is likely to have a short-circuit failure.

In this embodiment, before the resist film 53 is formed, the surface state of the substrate 50 is detected, and a state in which wettability is too high, a state in which bleeding is likely to occur, and a state in which deformation is likely to occur in the film shape are detected. When the surface condition of the substrate 50 supported by the table 23 is poor, the film formation apparatus notifies the operator of the poor surface condition without continuing the film formation (step S8 in fig. 3). When the operator finds the notification, the substrate 50 having a defective surface state is carried out of the film forming apparatus, and surface modification processing such as surface cleaning can be performed. Thereby, a decrease in the yield of the product can be suppressed.

In the present embodiment, as shown in fig. 6B, a bump 54 reflecting the shape of the evaluation pattern 55 (fig. 6A) is formed on the surface of the resist film 53. However, the resist film 53 is removed after the transparent conductive film 50b is etched. Further, since the resist film 53 is disposed inside the region where the resist film 53 is to be formed, the evaluation pattern 55 does not affect the planar shape of the resist film 53. Thus, the evaluation pattern 55 does not affect the shape of the transparent conductive film 50b (fig. 6D) after etching.

Next, various modifications of the present embodiment will be described.

In the above embodiment, the isolated plurality of dot patterns are used as the evaluation pattern 55 (fig. 4), but other patterns may be used. For example, two belt-like patterns having the same interval as the interval G, which becomes the minimum size of the resist film 53, may be used as the evaluation pattern 55. The quality of the surface state of the substrate 50 can be determined according to whether the interval of the formed band-like pattern is within an allowable range.

In the above embodiment, the evaluation pattern 55 (fig. 4) is formed on at least one portion of the substrate 50. According to the evaluation test by the inventors of the present application, it is found that the surface state of one substrate 50 differs depending on the position in the surface. For example, the inside of the substrate 50 tends to have higher wettability than the peripheral portion.

In consideration of variations in the surface state within the surface of one substrate 50, it is preferable to uniformly distribute the evaluation patterns 55 (fig. 4) within the surface of the substrate 50 in order to improve the accuracy of determination of the quality of the surface state. For example, it is preferable that the surface of the substrate 50 is divided at equal intervals in the row direction and the column direction, and one evaluation pattern 55 is formed in one divided area.

In the above embodiment, the resist film 53 is formed by moving the table 23 while the inkjet head 26 is stationary with respect to the base 20, but conversely, the inkjet head 26 may be moved while the table 23 is stationary with respect to the base 20. That is, one of the ink jet head 26 and the substrate 50 may be moved relative to the other.

Next, a film formation method according to another embodiment will be described with reference to fig. 8A and 8B. Hereinafter, differences from the embodiment shown in fig. 1 to 7B will be described, and description of the same structure will be omitted.

Fig. 8A is a cross-sectional view of the substrate 50 in a state where the evaluation pattern 55 is formed on the substrate 50 (step S4 in fig. 3). This process is the same as that of the embodiment shown in fig. 6A.

Fig. 8B is a cross-sectional view of the substrate 50 in a state where the resist film 53 is formed on the substrate 50 (step S7 in fig. 3). The arrows shown in fig. 8B correspond to the positions where the droplets of the resist film 53 are discharged. In the present embodiment, the control device 30 (fig. 1) creates correction pattern data, which is obtained by defining an evaluation pattern from among pixels of pattern data of the resist film 53 to be formed, which are removed from the application target. The inkjet head 26 is controlled based on the corrected pattern data, thereby forming the resist film 53. As shown by the arrows in fig. 8B, the application droplets are not overlapped on the dot pattern of the evaluation pattern 55 (fig. 8A).

In this example, the resist film 53 is formed without overlapping the application droplets on the pixels on which the evaluation pattern 55 (fig. 8A) is formed. Therefore, the generation of the bulge 54 appearing in the embodiment shown in fig. 6B can be prevented.

As in the embodiments shown in fig. 1 to 7B, when the resist film 53 is finally removed, there is no problem even if the ridge 54 is formed, but when a film remaining in the final product is formed, the embodiments shown in fig. 8A and 8B are preferably applied.

The above embodiments are merely examples, and it is needless to say that partial replacement or combination of the structures shown in different embodiments can be performed. The same operational effects based on the same structure in the plurality of embodiments are not mentioned one by one for each embodiment. Further, the present invention is not limited to the above embodiments. For example, it is obvious that those skilled in the art can make various alterations, improvements, combinations, and the like.

Description of the symbols

20-stage, 21-moving mechanism, 23-stage (support), 24-gate frame, 26-inkjet head, 27-camera, 30-control, 31-storage, 35-input, 36-output, 50-substrate, 50 a-glass substrate, 50 b-transparent conductive film, 51-pad, 52-connection, 53-resist, 53 a-target shape of resist, 53 b-bleed, 54-bump, 55-evaluation pattern, 56-normal dot pattern, 57-large dot pattern, 58-bled dot pattern, 58 a-bled dot pattern body, 58 b-bleed, 59-deformed dot pattern.

Claims

1. A film forming apparatus, comprising:

an imaging device that images the surface of the substrate disposed on the film forming section; and

a control section for controlling the film forming section,

before forming a film based on the pattern data, the control section controls the film forming section to form an evaluation pattern composed of the same material as a film to be formed in a part inside a region where a film material is applied for forming the film,

2. A film forming apparatus, comprising:

a control section for controlling the film forming section,

the control unit determines whether the surface state of the substrate is good or bad based on the image, executes film formation processing based on the pattern data on the substrate on which the evaluation pattern is formed when the surface state of the substrate is determined to be good, and executes other processing when the surface state of the substrate is determined to be bad.

3. The film-forming apparatus according to claim 2,

in the determination of the quality of the surface state of the substrate, the control section performs the quality determination based on at least one determination condition of whether the size of the evaluation pattern is within an allowable range, whether the bleeding width around the evaluation pattern is within an allowable range, and whether the deformation of the planar shape is within an allowable range.

4. The film-forming apparatus according to any one of claims 1 to 3,

the film forming part includes:

a support portion that supports the substrate;

an ink jet head for discharging a film material to the substrate supported by the support unit; and

a moving mechanism that moves one of the substrate and the inkjet head supported by the support portion relative to the other,

the control unit controls the inkjet head and the moving mechanism.

5. A film forming apparatus, comprising:

an imaging device that images the surface of the substrate disposed on the film forming section;

a control unit for controlling the film forming unit; and

an output unit that outputs information in accordance with an instruction from the control unit,

the control section determines whether the surface state of the substrate is good or bad based on the acquired image,

when the surface state of the substrate is determined to be defective, the control unit outputs information notifying that the surface state of the substrate is defective to the output unit,

the control section forms the film on the substrate based on the pattern data when the surface state of the substrate is determined to be good.

6. A film forming apparatus, comprising:

a control section for controlling the film forming section,

the control section determines whether the surface state of the substrate is good or bad based on the acquired image, and performs different processes based on the determination result,

the control unit applies droplets for forming the film to a portion where the evaluation pattern is formed, in a superposed manner.

7. A film forming apparatus, comprising:

a control section for controlling the film forming section,

when the film is formed based on the pattern data, the control unit forms the film based on corrected pattern data obtained by removing a portion where the evaluation pattern is formed from the pattern data.

8. A method of forming a film, wherein,