JP2006215121A - Gelation control method, film forming method, device manufacturing method, electro-optical device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gelation control method for controlling gelation of a liquid material with high accuracy, to provide a film forming method for stably forming a film in a desired shape on a substrate with high accuracy by using the gelation control method, to provide a device manufacturing method which can attain improvement in quality, and to provide an electro-optical device and electronic equipment. <P>SOLUTION: The film forming method is carried out by preparing a liquid material as liquid drops and depositing the drops on the substrate to form a film, wherein gelation of the liquid material is controlled by using at least either the solid content concentration of the liquid material or the drying rate of the liquid drops as a parameter so as to control the shape of a dry film of the liquid drops. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a gelation control method, a film formation method, a device manufacturing method, an electro-optical device, and an electronic apparatus.

An electro-optical device used as a display, a display light source, or the like, or an electronic device such as a semiconductor device includes a process of arranging a material on a substrate and forming a film on the substrate in the manufacturing process. Material placement technology and film formation technology are closely related to quality and function, and are important for improving the performance of each of the above devices.
As a technique for arranging a material on a substrate, there is a method of discharging a liquid material as droplets through a nozzle provided in an ejection head (see, for example, Patent Document 1).

This droplet discharge method is advantageous in that it consumes less liquid material and can easily control the amount and position of the liquid material placed on the substrate as compared with a technique such as spin coating.
The technique of forming a film on a substrate using the droplet discharge method requires placement accuracy when the liquid material is placed on the substrate, while improving and stabilizing the film shape after drying the liquid film. Desired.
However, the current situation is that a method for accurately controlling the film shape has not been established.

Japanese Patent Laid-Open No. 11-274671

  An object of the present invention is to provide a gelation control method capable of accurately controlling gelation of a liquid material, and to form a film having a desired shape on a substrate with high accuracy using this gelation control method. An object of the present invention is to provide a film forming method, a device manufacturing method capable of improving quality, an electro-optical device, and an electronic apparatus.

Such an object is achieved by the present invention described below.
The gelation control method of the present invention is characterized in that the gelation of the liquid material is controlled using at least one of the solid content concentration of the liquid material and the drying speed of the liquid material as a parameter.
Thereby, the gelation of the liquid material can be accurately controlled.

The film forming method of the present invention is a method of forming a film on a substrate by disposing a liquid material as droplets on the substrate,
The shape of the dried film of the droplet is controlled by controlling the gelation of the liquid material using at least one of the solid content concentration of the liquid material and the drying speed of the droplet as a parameter. To do.
Thereby, the dry film | membrane of a droplet can be controlled to various shapes. As a result, a desired film on the substrate can be formed accurately and stably.

In the film forming method of the present invention, it is preferable that the shape of the dry film includes a film thickness distribution of the dry film of the droplet and an outer diameter of the dry film of the droplet.
Thereby, the film thickness and the outer diameter can be controlled in the dried film of the droplet.
In the film forming method of the present invention, it is preferable that the parameter determines a flow of liquid in the droplet during drying.
Thereby, the gelation of the liquid material can be controlled to control the film thickness distribution of the dry film.

In the film forming method of the present invention, it is preferable to set the parameters so that the liquid material is gelled at the edge of the droplet earlier than the central portion of the droplet.
Thereby, a dry film having a large film thickness at the edge can be easily obtained.
In the film forming method of the present invention, it is preferable that the parameter is set so that the liquid material is gelled earlier than the edge of the droplet in the central portion of the droplet.
Thereby, a relatively flat dry film can be easily obtained.
In the film forming method of the present invention, it is preferable that the parameters are set so that the liquid material gels almost simultaneously in the entire droplet.
Thereby, a relatively flat dry film can be easily obtained.

In the film forming method of the present invention, at least one of a moving speed of a stage on which the substrate is mounted, an interval between droplets arranged on the substrate, and a contact angle of the substrate surface with the liquid material is controlled. It is preferable to change the drying speed of the droplets.
Accordingly, since the gelation of the liquid material is controlled to control the shape of the dried film of the droplet, a film pattern having a desired shape can be accurately and stably formed on the substrate.

The device manufacturing method of the present invention is a device manufacturing method in which a film pattern is formed on a substrate,
The film pattern is formed on the substrate by the film forming method of the present invention.
Thereby, various devices in which a desired film pattern is formed on the substrate can be manufactured.

The electro-optical device of the present invention includes a device manufactured using the device manufacturing method of the present invention.
Thereby, a high quality electro-optical device can be obtained stably.
An electronic apparatus according to the present invention includes the electro-optical device according to the present invention.
Thereby, a high quality electronic device can be obtained stably.

Hereinafter, a gelation control method, a film formation method, a device manufacturing method, an electro-optical device, and an electronic apparatus according to the present invention will be described based on the illustrated preferred embodiments.
The gelation control method of the present invention controls gelation of a liquid material by determining this parameter using at least one of the solid content concentration of the liquid material and the drying speed of the liquid material as a parameter.

Hereinafter, the case where the gelation control method of the present invention is applied to a film forming method will be described as an example.
FIG. 1 is a diagram schematically showing a typical droplet drying process in a film forming method to which the gelation control method of the present invention is applied.
In the film forming method of the present invention, a liquid material is formed as droplets on a substrate and dried to form a dried film of droplets on the substrate.
Although a case where one droplet is arranged on the substrate will be described here, the present invention is not limited to this, and includes, for example, a case where a plurality of droplets are arranged on the substrate and dried.
Further, as will be described later, it is also possible to form a linear film pattern on a substrate by continuously arranging dry films of a plurality of droplets.

In the film forming method of the present invention, in the drying process, by setting at least one of the solid content concentration of the liquid material and the drying speed of the liquid droplet as a parameter, the dry film of the liquid droplet is formed into various shapes by determining this parameter. Control.
Specifically, for example, as shown in FIG. 1A, the film thickness distribution can be controlled such that the film thickness of the edge of the dry film of the droplet is thicker than that of the central part. . Further, for example, as shown in FIG. 1B, the outer diameter can be controlled such that the diameter of the dried film of the droplet is reduced compared to the droplet after landing.

In the drying process shown in FIG. 1 (a), the above-described parameters (solid content concentration of liquid material, drying of droplets) so that the solid content concentration at the edge rises faster than the central portion of the droplet and gels. Speed).
Here, “gelation” means a state in which a fluid material having fluidity loses or reduces its fluidity and exhibits viscoelasticity, and “gelation point” means that the liquid material has viscoelasticity. And is defined as a transition point at which the solid component easily moves in the solution body.
In addition, “the state in which the liquid material exhibits viscoelasticity” refers to a state in which the liquid material placed on the substrate is deformed when stress is applied, but is restored to its original shape when the stress is removed. To tell.

  The solid content concentration in the liquid material at the gelation point is not particularly limited because it varies slightly depending on the type of solid content, the type of solvent, etc., but is preferably 45 wt% or more, and 55 wt% or more. It is good to be. As a result, there is sufficient time for the liquid material to spread until reaching the gel point, and the content of the liquid component (solvent or dispersion medium) in the liquid material is sufficiently reduced in the state of gelation. The obtained dry film has an improved density, high characteristics, and flatness.

In general, the liquid droplets disposed on the substrate are rapidly dried at the edges. In the drying process of the droplet, when the solid content concentration at the edge of the droplet reaches the gel point, the liquid material locally gels at the edge.
Then, the edge of the liquid droplet is pinned by the gelled portion, and the contraction of the liquid droplet (contraction of the outer diameter) accompanying the subsequent drying is suppressed.
Hereinafter, this phenomenon, that is, a phenomenon in which the shrinkage of the droplet accompanying the drying due to the gelation of the liquid material at the edge is suppressed is referred to as “pinning”.

On the other hand, in the drying process shown in FIG. 1B, the above parameters (solid content concentration of liquid material, droplet drying speed) are determined so that the solid content concentration of the entire droplet does not reach the gel point as much as possible. It is a thing.
In this case, since local gelation of the liquid material is unlikely to occur at the edge of the droplet, the above-described pinning does not occur, and the droplet shrinks with evaporation in the drying process. That is, as the drying progresses, the outer diameter of the droplet decreases.
Hereinafter, this phenomenon, that is, a phenomenon in which droplets contract without being pinned during drying is referred to as “depinning”.
In addition, the flow of the liquid in the droplet shown by the arrows in FIGS. 1A and 1B is an example and may be different from the actual one.

Here, among the above parameters, the drying speed of the droplets is the moving speed of the stage on which the substrate is mounted, the interval between the droplets arranged on the substrate (inter-droplet distance), the arrangement of a plurality of droplets, It changes according to the timing of arrangement and the contact angle of the substrate surface with respect to the liquid material.
For example, when the stage moves, drying of the droplets is promoted because the vapor concentration in the gas phase near the droplets decreases. As the moving speed of the stage increases, the moving speed of the droplet relative to the atmosphere increases, and the drying speed of the droplet increases.

FIG. 2 is a diagram showing an example in which a plurality of (here, two) droplets are arranged on a substrate.
As shown in FIG. 2, when the droplets are dried, the vapor that goes out from the liquid phase to the gas phase diffuses three-dimensionally around the droplets.
Here, the “vapor diffusion layer” refers to a region in which molecules evaporated from a droplet form a concentration gradient in the gas phase in the vicinity of the droplet due to movement by diffusion.

Here, a vapor layer formed in the gas phase near the droplet surface and having a concentration that affects other droplets is included as a vapor diffusion layer in a broad sense. Further, the distance between the droplets is the center distance between the two adjacent droplets.
The thickness of the vapor diffusion layer varies depending on the physical properties, solid content concentration, environmental temperature, etc. of the liquid material.

  When a plurality of droplets are arranged on the substrate, if the droplets exist in the vapor diffusion layer of another droplet or the vapor diffusion layers of both adjacent droplets partially overlap each other, the droplet surface The evaporation rate of the droplet changes due to a change in the vapor concentration of the liquid. Specifically, the shorter the distance between droplets and the longer the overlapping distance of the vapor diffusion layers, the smaller the evaporation rate (drying rate) of the droplets, and the longer the drying time.

On the other hand, when the vapor diffusion layers do not overlap, even if the distance between the droplets changes, the evaporation rate and drying time of the droplets hardly change.
Therefore, the drying speed of the droplets can be changed by changing the distance between the droplets (the interval between the droplets) within a range affected by the vapor diffusion layer.
In addition, when a plurality of droplets are arranged on the substrate, the drying time of the droplets varies depending not only on the distance between the droplets described above but also on the timing, number and arrangement of the droplets.

  For example, the drying (evaporation) state of the previous liquid droplet changes when the next liquid droplet is disposed, depending on the period from when the first liquid droplet is disposed on the substrate to when the next liquid droplet is disposed. Therefore, according to the change, the magnitude of the influence of the vapor diffusion layer between the droplets and the drying rate of the droplets change. That is, the longer the period, the less the influence of the vapor diffusion layer between the plurality of droplets, and the higher the drying rate of the droplets.

Further, as shown in FIGS. 3A and 3B, the larger the number of droplets B arranged in one droplet A within the range where the vapor diffusion layers overlap, the more the influence of the vapor diffusion layer is. It appears large and the drying speed of the droplet A becomes small.
Further, when one droplet B is disposed on one side of one droplet A as shown in FIG. 3A within the range where the vapor diffusion layers overlap, in the droplet A, the droplet B The drying speed on the side where the is disposed is partially reduced. In this case, since a partial deviation occurs in the drying speed, the shape of the dry film of the droplet A becomes anisotropic.
On the other hand, as shown in FIG. 3B, when a plurality of droplets B are arranged over the entire circumference of one droplet A, the above-described partial unevenness in the drying speed is unlikely to occur. The shape of the dry film A is isotropic.

FIGS. 4A and 4B show the state of liquid droplets when the contact angle (static contact angle) of the substrate surface with respect to the liquid material is different (contact angle θa <θb).
When the same amount of droplets is placed on the substrate, the smaller the contact angle, the larger the outer diameter of the droplets. Since the drying speed tends to increase when the outer diameter of the droplet is large, the drying speed increases as the contact angle of the substrate surface with the liquid material decreases.
Note that the contact angle is reduced by, for example, applying a lyophilic process for increasing the wettability with respect to the liquid material to the substrate surface, and applying a lyophobic process for reducing the wettability with respect to the liquid material to the substrate surface. It will be bigger.

From the above, the moving speed of the stage on which the substrate is mounted, the interval between droplets arranged on the substrate (distance between droplets), the arrangement and arrangement timing of a plurality of droplets, and the surface of the substrate relative to the liquid material By controlling the contact angle and the like, the drying speed of the droplets can be changed.
As a method of changing the drying speed of the droplets, in addition to the above, environmental factors such as temperature, humidity, and atmospheric pressure may be controlled, or a heating unit or a blowing unit may be used.
Moreover, these control methods can be used in combination of arbitrary two or more as needed.

FIG. 5 is a diagram showing time integration of the evaporation amount of the liquid (liquid component such as a solvent and a dispersion medium) from the droplets under a certain drying condition.
As shown in FIG. 5, in the initial stage of drying, the amount of evaporation per time is large (part A shown in FIG. 5). This is because in the initial stage of drying immediately after the droplets are placed on the substrate, the vapor concentration around the droplets is low and the drying rate (evaporation rate) of the droplets is high.
After that, when the periphery of the droplet (the average free process distance of the liquid molecules) reaches the saturation concentration, the drying rate of the droplet becomes a steady state limited by the diffusion rate of the vapor (part B shown in FIG. 5). Slower compared to the initial drying stage.

As described above, the droplets disposed on the substrate are rapidly dried at the edges. Therefore, at the initial stage of drying (part A shown in FIG. 5), the liquid (liquid component) rapidly evaporates at the edge of the droplet and the solid concentration tends to increase. At this time, when the solid content concentration at the edge of the droplet reaches the gel point, the above-described pinning occurs.
In the present invention, by controlling such a phenomenon, a dry film having a target shape (film thickness distribution and outer diameter) is formed.
6 to 8 respectively show the shape of the dry film formed through pinning, that is, the shape of the dry film formed by causing gelation of the liquid material at the edge of the droplet earlier than the central part. The right side is a plan view and the left side is a sectional view.
In addition, the dry film | membrane shown in FIGS. 6-8 differs from the said parameter in a drying process mutually.

<When forming the dry film shown in FIG. 6>
First, as shown in FIG. 6 (a), the droplets are arranged on the substrate, and then, as shown in FIG. 6 (b), after the droplets are enlarged (bottom area is increased), depinning is used. Then, as shown in FIG. 6C, drying is performed until the diameter is reduced to the target outer diameter (size: dimension) (bottom area is reduced).
The diameter of the droplets (depinning) can be adjusted, for example, by reducing the drying speed of the droplets as much as possible to prevent drying at an initial stage where the amount of evaporation per time is large.

Next, when the droplet reaches the target outer diameter, as shown in FIG.
Here, when pinning occurs, as shown in FIG. 1A, in the droplet, the liquid lost by evaporation at the edge of the droplet is supplemented from the central portion, that is, from the central portion. A liquid flow towards the edge is formed. This liquid flow changes in accordance with the above parameters.

The dry film shown in FIG. 6 is formed by determining the above parameters so that the liquid flow from the central part to the edge part is strongly formed in the droplets during drying.
As shown in FIG. 1 (a), after a pinning occurs, if a liquid flow from the center to the edge is strongly formed in the droplet, the droplet flows along with the liquid flow. A lot of solids are carried to the edge.

At the edge of the droplet, the flow of the liquid tends to stay due to the progress of viscoelasticity accompanying the gelation of the liquid material, and the high concentration state of the solid content is maintained. That is, the liquid flow from the edge to the center is weaker than the liquid flow from the center to the edge.
As a result, the solid content at the edge of the droplet is greater than that at the center, and the film thickness at the edge of the dry film is increased.
In this case, among the above parameters, the lower the solid content concentration of the liquid material and the higher the drying speed, the stronger the liquid flow from the center to the edge.

Therefore, by reducing the solid content concentration of the liquid material or increasing the drying speed, it is possible to control the gelation of the liquid material and increase the film thickness ratio of the edge to the center of the dry film. it can. That is, as shown in FIG. 6 (e), a dry film having a thick edge, that is, a dry film in which the film thickness distribution is controlled to the target is formed.
In addition, when the solid content is fine particles, the smaller the particle size of the fine particles, the easier it is to carry the solid content to the edge by being placed on the liquid flow, and thus the thickness of the central portion of the dry film tends to be thin. By increasing the film thickness ratio of the edge to the center of the dry film, for example, a ring-shaped dry film is formed as shown in FIG.

<When forming the dry film shown in FIG. 7>
The dry film shown in FIG. 7 is formed by determining the above parameters so that the flow of liquid from the center to the edge in the droplet is weaker than in the case of obtaining the dry film shown in FIG. is there.
Of the above parameters, the higher the solid content concentration of the liquid material and the lower the drying speed, the weaker the liquid flow from the center to the edge and the less likely it is to carry the solid to the edge of the droplet. .
Further, when the solid content is fine particles, the larger the particle size of the fine particles, the more difficult it is to carry the solid content from the central portion of the droplet to the edge portion, and thus the thickness of the central portion of the dry film is less likely to be thin.
As a result, as shown in FIG. 7, a dry film having a substantially flat cross-sectional shape is formed in which the central portion and the edge portion have the same film thickness.

<When forming the dry film shown in FIG. 8>
The dry film shown in FIG. 8 is formed by setting the above parameters so that the flow of liquid from the center to the edge in the droplet is weaker than when the dry film shown in FIG. 7 is obtained. is there.
The dry film shown in FIG. 8 has, for example, a higher solid content concentration of the liquid material, a lower drying speed, and a larger particle size of the solid content as compared with the dry film shown in FIGS. In this case, it is difficult to carry the solid content from the central portion of the droplet to the edge portion, and as shown in FIG. 8, the thickness of the central portion is thicker than the edge portion of the dry film.

In this way, under the conditions in which pinning occurs, the above parameters (solid content concentration of liquid material, droplet drying speed) or the particle size of fine particles are changed to control the gelation of the liquid material. The dry film of the droplet can be controlled in various shapes.
Further, with respect to the ring-shaped dry film having a thick edge portion, it is possible to control the width and the like of the raised portion of the edge portion by changing the parameters and the particle diameter of the fine particles.
Specifically, the higher the concentration and the larger the particle size of the fine particles, the less the influence of the liquid flow from the center to the edge, so that the film shape approaches flat and the width of the raised portion of the edge Shows a tendency to narrow.

FIG. 9 is a diagram showing a change in the film shape when the solid content concentration of the liquid material and the particle diameter of the fine particles are changed with respect to the dry film formed through pinning. .
Here, the particle diameter of the fine particles: (a) <(b), and the solid content concentration of the liquid material: (a) <(b).

The outer diameter of the dry film of (a) is W ₁ , the thickness of the edge is h ₁ , the width of the raised part of the edge is L ₁ , the outer diameter of the dry film of (b) is W ₂ , W ₁ <W ₂ , h ₁ <h ₂ , L ₁ > L ₂ when the thickness is h ₂ and the width of the raised portion of the edge is L ₂ .
Note that another droplet may be placed on the droplet being dried by pinning. In this case, the liquid content of the droplets being dried increases, so that the liquid flow from the center to the edge is maintained, and the solid content is further conveyed to the edge. Therefore, the movement of the solid content to the edge is promoted, and the film thickness of the edge tends to be further increased.

Further, the affinity of the substrate surface with respect to the liquid material may be controlled, and the boundary portion where the affinity changes may act as an incentive for pinning.
In addition, when the liquid material disposed on the substrate is heated, or when a low boiling point solvent or dispersion medium is used to prepare the liquid material, the change in the film shape due to the above parameters becomes significant.

FIG. 10 is a diagram showing the shape of a dry film formed by causing the liquid material to gel before the edge at the center of the droplet. The right side is a plan view and the left side is a cross-sectional view.
First, as shown in FIG. 10 (a), the droplets are arranged on the substrate, and then, as shown in FIG. 10 (b), the droplets are expanded in diameter (the bottom area is increased), and then depinning is used. Then, as shown in FIG. 10C, the diameter of the droplet is reduced (the bottom area is reduced).

Next, when the droplet reaches the target outer diameter, as shown in FIG. 10D, the liquid material is gelled before the edge portion at the center of the droplet. Thereby, the center part of a droplet will be in the state similar to the said pinning.
In this state, in the same manner as in the case of forming the dry film shown in FIG. 7, the above parameters are set so that the flow of liquid from the edge to the center in the droplet is weakened. ), A dry film having a substantially flat cross-sectional shape can be formed.

FIG. 11 is a diagram showing the shape of a dry film formed by causing gelation of a liquid material almost simultaneously in the entire droplet, and the right side is a plan view and the left side is a cross-sectional view.
First, as shown in FIG. 11 (a), the droplets are arranged on the substrate, and then, as shown in FIG. 11 (b), after the droplets have expanded in diameter (the bottom area increases), depinning is used. Then, as shown in FIG. 11C, the diameter of the droplet is reduced (the bottom area is reduced).

Next, when the droplet reaches the target outer diameter, as shown in FIG. 11D, the liquid material is gelled almost simultaneously in the entire droplet.
Here, as shown in FIG. 1B, in the drying process by depinning, the droplet contracts with evaporation (for example, contraction ratio: 1/2 or less).
In the droplet contraction process, a convection including a liquid flow from the center to the edge and a flow from the edge to the center is continuously formed in the droplet, and a local convection is generated in the droplet. The rise in the solid content concentration is suppressed, and the solid content concentration in the droplets is made uniform.

Therefore, in this state, if gelation occurs in the liquid material almost simultaneously in the entire droplet, the droplet becomes viscoelastic while maintaining its shape in the contraction process, and then solidifies.
As a result, as shown in FIG. 11 (e), the dry film has a thickness approximately equal to the central portion and the edge portion, or is slightly larger than the edge portion. Become.
6, 10, and 11, the outer diameter of the droplet may be slightly reduced in the process from (d) to (e).
Further, in the film formation by such a method, since the droplet is contracted in the drying process, it is possible to form an extremely minute film on the substrate.

In addition to this, it is possible to form a film having various characteristics, for example, by forming a film having a dense structure (such as a colloidal crystal) by utilizing the shrinkage of the droplets during the drying process.
Further, in film formation by such a method, for a predetermined amount of droplets, the higher the solid content concentration of the liquid material, the larger the diameter of the dry film. On the contrary, it is possible to form a very small thin film by keeping the solid content concentration of the liquid material low. In this case, even when there is a lower limit to the amount of droplets that can be placed on the substrate, the shrinkage ratio of the droplets during the drying process is controlled by adjusting the solid content concentration of the liquid material and controlling the gelation of the liquid material. And a very small dry film can be formed on the substrate.

As described above, according to the film forming method of the present invention, at least one of the solid content concentration of the liquid material and the drying speed of the droplet is changed to control the gelation of the liquid material in the droplet. Thus, the dry film of the droplets can be controlled in various shapes. As a result, a film having a desired shape can be accurately and stably formed on the substrate.
Therefore, it is possible to improve device quality by manufacturing an electronic device using this film forming method.

Moreover, the ring-shaped dry film | membrane shown in FIG. 6 can be preferably utilized as a container (bank) or a foundation of another material. That is, when another material is disposed inside the edge of the ring-shaped thin film, the bulge of the edge serves as a wall, thereby improving the material placement accuracy.
In addition, the dry films shown in FIGS. 10 and 11 can be applied to various fields because miniaturization and improvement of film properties can be achieved.
Such a dry film can be preferably used for high definition of various electronic devices such as semiconductor elements, TFT elements, and EL elements.

  Further, when droplets are placed on a substrate using the droplet discharge method, the amount of droplets that can be discharged has a lower limit, but according to the film forming method of the present invention, the same apparatus as in the past can be used. As compared with a droplet immediately after landing, a minute film can be easily formed. In this case, it is possible to form a minute film equivalent to or more than that of a device capable of discharging femtoliter (fL) droplets using a conventional device.

  In addition, the colloidal crystal film formed by using the film forming method of the present invention can be preferably used for a thin film in an organic EL, an electrode in an organic TFT, and the like because of high conductivity and pure characteristics. Moreover, since the structure can be easily crystallized by crystallization of the film, it can be used for structural analysis of proteins and the like in the fields of biotechnology and pharmaceuticals. It can also be used as an optical member.

As described above, in the film forming method of the present invention, either a solution or a dispersion can be used as the liquid material.
Here, when the liquid material to be used is a solution, examples of the solute include biological materials (biological substances) such as resin materials, oxide precursors, alloy catalyst precursors, proteins, amino acids, nucleic acids, hormones, and saccharides. Related substances).
On the other hand, when the liquid material used in the present invention is a dispersion, examples of the dispersoid include metal particles such as resin particles, Au particles, and Ag particles.
The solvent or dispersion medium (liquid component) used for preparing the liquid material may be appropriately selected according to the type of the solvent or dispersion medium.

Next, a film forming apparatus suitably used for the film forming method of the present invention will be described.
FIG. 12 is a diagram showing a configuration example of a film forming apparatus suitably used in the film forming method of the present invention.
In FIG. 12, a film forming apparatus 10 is provided on a base 112, a substrate stage 22 that supports the substrate 20, and is interposed between the base 112 and the substrate stage 22 so that the substrate stage 22 can be moved. A first moving device (moving device) 114 supported by the substrate stage, a liquid ejecting head 21 capable of ejecting the processing liquid to the substrate 20 supported by the substrate stage 22, and a first supporting device movably supporting the liquid ejecting head 21. A two-movement device 116 and a control device 23 for controlling the droplet discharge operation of the liquid discharge head 21.
Further, the film forming apparatus 10 includes an electronic balance (not shown) as a weight measuring device provided on the base 112, a capping unit 25, and a cleaning unit 24.
The operation of the film forming apparatus 10 including the first moving device 114 and the second moving device 116 is controlled by the control device 23.

The first moving device 114 is installed on the base 112 and is positioned along the Y direction.
The second moving device 116 is mounted upright with respect to the base 112 using the support columns 16 </ b> A and 16 </ b> A, and is mounted at the rear portion 12 </ b> A of the base 112.
The X direction (second direction) of the second moving device 116 is a direction orthogonal to the Y direction (first direction) of the first moving device 114.
Here, the Y direction is a direction along the front 12B and rear 12A directions of the base 112. On the other hand, the X direction is a direction along the left-right direction of the base 112 and is horizontal. The Z direction is a direction perpendicular to the X direction and the Y direction.

The first moving device 114 is configured by, for example, a linear motor, and includes guide rails 140 and 140 and a slider 142 provided to be movable along the guide rail 140. The slider 142 of the first moving device 114 of this linear motor type can be positioned by moving in the Y direction along the guide rail 140.
Further, the slider 142 includes a motor 144 for rotating around the Z axis (θZ). The motor 144 is, for example, a direct drive motor, and the rotor of the motor 144 is fixed to the substrate stage 22.
Thus, by energizing the motor 144, the rotor and the substrate stage 22 can rotate along the θZ direction to index (rotate index) the substrate stage 22. That is, the first moving device 114 can move the substrate stage 22 in the Y direction (first direction) and the θZ direction.
The substrate stage 22 holds the substrate 20 and positions it at a predetermined position.
The substrate stage 22 has a suction holding device (not shown). When the suction holding device is operated, the substrate 20 is sucked and held on the substrate stage 22 through the hole 46A of the substrate stage 22.

The second moving device 116 is constituted by a linear motor, and is supported by a column 16B fixed to the columns 16A and 16A, a guide rail 62A supported by the column 16B, and movable in the X direction along the guide rail 62A. The slider 160 is provided.
The slider 160 can be positioned by moving in the X direction along the guide rail 62 </ b> A, and the liquid discharge head 21 is attached to the slider 160.

The liquid discharge head 21 has motors 62, 64, 67, 68 as swing positioning devices.
If the motor 62 is operated, the liquid ejection head 21 can be positioned by moving up and down along the Z axis. The Z axis is a direction (vertical direction) orthogonal to the X axis and the Y axis.
When the motor 64 is operated, the liquid discharge head 21 can be positioned by swinging along the β direction around the Y axis.

When the motor 67 is operated, the liquid discharge head 21 can be positioned by swinging in the γ direction around the X axis.
When the motor 68 is operated, the liquid discharge head 21 can be positioned by swinging in the α direction around the Z axis.
That is, the second moving device 116 supports the liquid discharge head 21 so as to be movable in the X direction (first direction) and the Z direction, and can move the liquid discharge head 21 in the θX direction, the θY direction, and the θZ direction. To support.

12 can be positioned by linearly moving in the Z-axis direction in the slider 160, and can be positioned by swinging along α, β, and γ. The droplet discharge surface 11P can be accurately controlled in position or posture with respect to the substrate 20 on the substrate stage 22 side.
A plurality of nozzles for discharging droplets are provided on the droplet discharge surface 11P of the liquid discharge head 21.

The liquid discharge head 21 discharges a liquid material (resist) from a nozzle by a so-called liquid discharge method (droplet discharge method).
As the liquid ejection method, various known techniques such as a piezo method that ejects ink using a piezoelectric element as a piezoelectric element, and a method that ejects liquid material using bubbles generated by heating the liquid material are applied. it can.
Among these, the piezo method has an advantage that it does not affect the composition of the material because no heat is applied to the liquid material. In the present embodiment, the piezo method is used.

FIG. 13 is a diagram for explaining the discharge principle of the liquid material by the piezo method.
In FIG. 13, a piezo element 32 is installed adjacent to a liquid chamber 31 for storing a liquid material.
The liquid material is supplied to the liquid chamber 31 via a liquid material supply system 34 including a material tank that stores the liquid material.

The piezo element 32 is connected to a drive circuit 33, and a voltage is applied to the piezo element 32 via the drive circuit 33. By deforming the piezo element 32, the liquid chamber 31 is deformed and the liquid material is discharged from the nozzle 30.
At this time, the amount of distortion of the piezo element 32 is controlled by changing the value of the applied voltage, and the speed of distortion of the piezo element 32 is controlled by changing the frequency of the applied voltage. That is, in the liquid ejection head 21, the ejection of the liquid material from the nozzle 30 is controlled by controlling the voltage applied to the piezo element 32.

Returning to FIG. 12, the electronic balance (not shown) measures, for example, the weight of one droplet discharged from the nozzle of the liquid discharge head 21 and manages, for example, 5000 from the nozzle of the liquid discharge head 21. Receive a drop of drops.
The electronic balance can accurately measure the weight of one droplet by dividing the weight of the 5000 droplet by the number of 5000.
Based on the measured amount of droplets, the amount of droplets ejected from the liquid ejection head 21 can be optimally controlled.

The cleaning unit 24 can clean the nozzles and the like of the liquid discharge head 21 periodically or at any time during the device manufacturing process or during standby.
The capping unit 25 covers the droplet discharge surface 11P during standby when the device is not manufactured in order to prevent the droplet discharge surface 11P of the liquid discharge head 21 from drying.

By moving the liquid discharge head 21 in the X direction by the second moving device 116, the liquid discharge head 21 can be selectively positioned above the electronic balance, the cleaning unit 24, or the capping unit 25.
That is, even during the device manufacturing operation, the weight of the droplet can be measured by moving the liquid discharge head 21 to the electronic balance side, for example.

If the liquid discharge head 21 is moved onto the cleaning unit 24, the liquid discharge head 21 can be cleaned.
If the liquid discharge head 21 is moved onto the capping unit 25, a cap is attached to the droplet discharge surface 11P of the liquid discharge head 21 to prevent drying.
That is, the electronic balance, the cleaning unit 24, and the capping unit 25 are disposed on the rear end side on the base 112 and immediately below the movement path of the liquid discharge head 21 and separated from the substrate stage 22.
Since the supply work and the discharge work of the substrate 20 with respect to the substrate stage 22 are performed on the front end side of the base 112, the electronic balance, the cleaning unit 24, or the capping unit 25 does not interfere with the work.

As shown in FIG. 12, in the portion of the substrate stage 22 other than the substrate 20 that supports the substrate 20, a preliminary discharge area (preliminary discharge) for the liquid discharge head 21 to discard or trial strike (preliminary discharge) is used. A discharge area 152 is provided separately from the cleaning unit 24.
As shown in FIG. 12, the preliminary ejection area 152 is provided along the X direction on the rear end side of the substrate stage 22.
This preliminary discharge area 152 is fixed to the substrate stage 22 and has a concave-shaped receiving member that opens upward, and an absorbent material that is exchangeably installed in the concave portion of the receiving member and absorbs the discharged droplets. It is composed of

As the substrate 20, various substrates such as a glass substrate, a silicon substrate, a quartz substrate, a ceramic substrate, a metal substrate, a plastic substrate, and a plastic film substrate can be used. In addition, a substrate in which a semiconductor film, a metal film, a dielectric film, an organic film, or the like is formed as a base layer on the surface of these various material substrates is also included. Examples of the plastic include polyolefin, polyester, polyacrylate, polycarbonate, polyethersulfone, and polyetherketone.
In the film forming apparatus, when the droplets ejected from the liquid ejection head are arranged on the substrate, the drying speed of the droplets is controlled by moving the substrate stage or the like. The method for drying the droplets is not limited to this, and for example, the droplets may be dried using a drying means such as lamp annealing.

FIG. 14 is a diagram showing a film pattern forming method to which the film forming method of the present invention is applied.
FIGS. 14A to 14C show an example of a procedure of a method for forming a linear film pattern on a substrate using the above-described film forming apparatus 10 as an example of a film pattern forming method. .
In this film pattern forming method, a liquid material is discharged from the discharge head 21 as droplets, and the droplets are arranged on the substrate 20 at a certain distance (pitch). Then, a linear film pattern is formed on the substrate 20 by repeating this droplet placement operation.
Specifically, first, as shown in FIG. 14A, the droplets L1 ejected from the ejection head 21 are sequentially arranged on the substrate 20 with a certain interval.

After the droplet L1 is placed on the substrate 20, a drying process is performed in order to remove the liquid (liquid component such as a solvent and a dispersion medium).
The drying process may be performed by moving the stage on which the substrate 20 is mounted, in addition to a general heating process using heating means such as a hot plate, an electric furnace, a hot air generator, and lamp annealing.
Further, in the present embodiment, as described above, the gelation of the liquid material is controlled using at least one of the solid content concentration of the liquid material and the drying speed of the droplet as a parameter, so that the dry film of the droplet can be controlled. Control the shape.

Next, as shown in FIG. 14B, the above-described droplet placement operation is repeated.
That is, as in the previous time shown in FIG. 14A, the liquid material is discharged from the discharge head 21 as droplets L2, and the droplets L2 are arranged on the substrate 20 at regular intervals.
At this time, the amount of the droplet L2 (the amount of the liquid material per droplet) and the arrangement pitch P2 thereof are the same as the previous droplet L1.

Further, the arrangement position of the droplet L2 is shifted by a predetermined distance S1 from the previous droplet L1. That is, the center position of the previous droplet L1 disposed on the substrate 20 and the center position of the current droplet L2 are in a positional relationship separated by the distance S1.
In this embodiment, the shift amount S1 is narrower than the pitches P1 and P2 (S1 <P1 = P2), and the next droplet L2 partially overlaps the droplet L1 previously disposed on the substrate 20. It is stipulated in.
At this time, the current droplet L2 and the previous droplet L1 are in contact with each other. However, since the liquid component of the previous droplet L1 has already been completely or removed to some extent, they merge together on the substrate 20. Spreading can be suppressed.

After the droplet L2 is placed on the substrate 20, a drying process is performed in the same manner as the previous time in order to remove the liquid component.
Thereafter, as shown in FIG. 14C, the above-described droplet placement operation is repeated a plurality of times.
At each time, the distance interval (pitch Pn) between the droplets Ln to be arranged is the same as the distance of the first time (pitch Pn = P1), and is always constant.
Further, when the droplet placement operation is repeated a plurality of times, the position at which the placement of the droplet Ln is started is shifted by a predetermined distance from the position at which the previous droplet is placed each time.
By repeating this droplet placement operation, gaps between the droplets placed on the substrate 20 are filled, and a linear continuous pattern is formed.

In addition, the film pattern formed on the substrate is always formed by droplet arrangement with the same pitch, and the whole undergoes a substantially equal forming process, so that the structure is uniform.
In such a film pattern forming method, the gelation of the liquid material is controlled to control the shape of the dry film of the droplets, so that a film pattern having a desired shape can be accurately and stably formed on the substrate. Can do.
Note that the linear film pattern forming method is not limited to that shown in FIGS. For example, the arrangement pitch of the droplets, the shift amount at the time of repetition, and the like can be arbitrarily set.
According to such a film pattern forming method, various devices in which a desired film pattern is formed on a substrate can be manufactured.

FIG. 15 is a perspective view illustrating the configuration of a liquid crystal display device (electro-optical device) equipped with a color filter manufactured using the device manufacturing method of the present invention.
The liquid crystal display device 400 according to this embodiment is equipped with auxiliary elements such as a liquid crystal driving IC (not shown), wirings (not shown), a light source 470, a support (not shown), and the like.
The configuration of the liquid crystal display device 400 will be briefly described.

The liquid crystal display device 400 is a kind of electro-optical device. The color filter 460 and the glass substrate 414 arranged so as to face each other, a liquid crystal layer (not shown) sandwiched therebetween, and the upper surface of the color filter 460. It is mainly composed of a polarizing plate 416 attached to the side (observer side) and a polarizing plate (not shown) attached to the lower surface side of the glass substrate 414.
The color filter 460 includes a substrate 461 made of transparent glass as a main material and is a substrate provided on the viewer side, and the glass substrate 414 is a transparent substrate provided on the opposite side.

A partition wall 462 made of a black photosensitive resin film, a colored portion 463, and an overcoat layer 464 are sequentially formed below the substrate 461, and a driving electrode 418 is formed below the overcoat layer 464. Has been.
Note that in the actual liquid crystal device, an alignment film is provided on the liquid crystal layer side and the electrode 432 (to be described later) on the glass substrate 414 side so as to cover the electrode 418, but illustration and description thereof are omitted here.

The liquid crystal driving electrode 418 formed on the liquid crystal layer side of the color filter 460 is formed by forming a transparent conductive material such as ITO (Indium Tin Oxide) on the entire surface of the overcoat layer 464.
An insulating layer 425 is formed on the glass substrate 414, and a TFT (Thin Film Transistor) as a switching element and a pixel electrode 432 are formed on the insulating layer 425.

A scanning line 451 and a signal line 452 are formed in a matrix over the insulating layer 425 formed over the glass substrate 414, and a pixel electrode 432 is formed for each region surrounded by the scanning line 451 and the signal line 452. Is provided.
A TFT is incorporated in a corner portion of each pixel electrode 432 and a portion between the scanning line 451 and the signal line 452, and the TFT is turned on or off by applying a signal to the scanning line 451 and the signal line 452. Energization to the pixel electrode 432 is controlled.

FIG. 16 is a perspective view illustrating the configuration of a mobile phone which is an example of an electronic apparatus using the liquid crystal display device (electro-optical device).
In FIG. 16, a mobile phone 92 includes the above-described liquid crystal display device (electro-optical device) 400 in addition to a plurality of operation buttons 921, as well as an earpiece 922 and a mouthpiece 923.

The device manufacturing method of the present invention is not limited to the patterning of color filters used in electro-optical devices, and can be used for forming various film patterns as follows. For example, it can be used for forming thin films such as an organic EL layer and a hole injection layer included in an organic EL (electroluminescence) display panel.
In the case of forming an organic EL layer, for example, a droplet containing an organic EL material such as a polythiophene-based conductive polymer is discharged toward a region partitioned by a partition formed on the substrate, and the droplet is Place in the area. The organic EL layer is formed by drying the liquid material arranged in this way.

  Other application examples of the device manufacturing method of the present invention include auxiliary wiring for transparent electrodes included in plasma displays, formation of devices such as antennas included in IC (integrated circuit) cards, and the like. Specifically, after a solution obtained by mixing conductive fine particles such as silver fine particles in an organic solution such as tetradecane is patterned using a droplet discharge device, a metal thin film layer is formed when the organic solution is dried.

In addition to the above, the device manufacturing method of the present invention includes, for example, thermosetting resins and ultraviolet curable resins used for three-dimensional modeling, microlens array materials, biological substances such as DNA (deoxyribonucleic acid) and proteins, and the like It can also be used for the arrangement of various materials.
In addition to mobile phones, electronic devices include computers, projectors, digital cameras, movie cameras, PDAs (Personal Digital Assistants), in-vehicle devices, copying machines, audio devices, and the like.
As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

It is a figure which shows typically the drying process of the typical droplet in the film formation method to which the gelation control method of this invention is applied. It is a figure which shows the example which has arrange | positioned the several droplet on a board | substrate. It is a figure which shows the example of an arrangement | sequence of a some droplet. It is a figure which shows the mode of the droplet when the contact angle (static contact angle) of the substrate surface with respect to a liquid material differs mutually. It is a figure which shows the time integration of the evaporation amount of the liquid from a droplet on fixed drying conditions. It is a figure which shows the shape of the dry film | membrane formed through pinning. It is a figure which shows the shape of the dry film formed through pinning. It is a figure which shows the shape of the dry film | membrane formed through pinning. It is a figure which shows the mode of a film | membrane shape change when the solid content concentration and droplet diameter of a liquid material are changed regarding the dry film | membrane formed through pinning especially about a ring-shaped film | membrane. It is a figure which shows the shape of the dry film | membrane formed by producing gelation of a liquid material earlier than an edge part in the center part of a droplet. It is a figure which shows the shape of the dry film | membrane formed by producing the gelation of a liquid material substantially simultaneously in the whole droplet. It is a figure which shows the structural example of the film formation apparatus used suitably for the film formation method of this invention. It is a figure for demonstrating the discharge principle of the liquid material by a piezo system. It is a figure which shows the film | membrane pattern formation method to which the film | membrane formation method of this invention is applied. It is a perspective view which illustrates the composition of the liquid crystal display (electro-optical device) carrying the color filter manufactured using the device manufacturing method of the present invention. FIG. 11 is a perspective view illustrating the configuration of a mobile phone that is an example of an electronic apparatus using a liquid crystal display device (electro-optical device).

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Film formation apparatus 11P ... Droplet discharge surface 112 ... Base 114 ... 1st moving device 116 ... 2nd moving device 12A ... Rear part 12B ... Front part 16A ... Support | pillar 16B ... Column 140 ... ... guide rail 142 ... slider 144 ... motor 152 ... preliminary ejection area 160 ... slider 20 ... substrate 21 ... liquid ejection head 22 ... substrate stage 23 ... control device 24 ... cleaning unit 25 ... capping unit 30 ... ... nozzle 31 ... liquid chamber 32 ... piezo element 33 ... drive circuit 34 ... liquid material supply system 46A ... hole 62A ... guide rails 62, 64, 67, 68 ... motor 400 ... liquid crystal display 414 ... Glass substrate 416 ... Polarizing plate 418 ... Electrodes 425 ... Insulating layer 432 ... Electrode (pixel electrode) 451 ... Scanning line 452 ... Signal line 460 ... Color filter 461 ... Substrate 462 ... Partition 463 ... Colored part 464 ... Overcoat layer 470 ... Light source 92 ... Mobile phone 921 ... ... operation buttons 922 …… Entrance 923 …… Speaker

Claims (11)

  A gelation control method characterized by controlling gelation of the liquid material using at least one of a solid content concentration of the liquid material and a drying speed of the liquid material as a parameter. A method of forming a film on the substrate by disposing a liquid material as droplets on the substrate,
The shape of the dried film of the droplet is controlled by controlling the gelation of the liquid material using at least one of the solid content concentration of the liquid material and the drying speed of the droplet as a parameter. Film forming method.   The film forming method according to claim 2, wherein the shape of the dry film includes a film thickness distribution of the dry film of the droplet and an outer diameter of the dry film of the droplet.   The film forming method according to claim 2, wherein the parameter determines a flow of liquid in the droplet during drying.   5. The film forming method according to claim 2, wherein the parameter is set so that the liquid material is gelled at an edge portion of the droplet earlier than a central portion of the droplet.   5. The film forming method according to claim 2, wherein the parameter is set so that the liquid material is gelled at a central portion of the droplet earlier than an edge portion of the droplet.   5. The film forming method according to claim 2, wherein the parameter is set so that the liquid material is gelled substantially simultaneously in the entire droplet.   By controlling at least one of a moving speed of a stage on which the substrate is mounted, an interval between droplets arranged on the substrate, and a contact angle of the substrate surface with respect to the liquid material, The film forming method according to claim 2, wherein the drying speed is changed. A device manufacturing method in which a film pattern is formed on a substrate,
A device manufacturing method, wherein the film pattern is formed on the substrate by the film forming method according to claim 2.   An electro-optical device comprising a device manufactured using the device manufacturing method according to claim 9.   An electronic apparatus comprising the electro-optical device according to claim 10.

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