JP4449602B2 - Droplet discharge apparatus and film pattern forming method - Google Patents

Description

  The present invention relates to a droplet discharge device that controls the discharge operation based on the discharge characteristics of a droplet discharge head, and a film pattern forming method using the droplet discharge device.

  Conventionally, as a thin film forming technique, a spin coating method, which is one of thin film coating methods, is generally used. This spin coating method is a method of forming a thin film by rotating the substrate and applying the entire surface of the substrate by centrifugal force after dropping the coating solution onto the substrate. The film thickness is controlled by viscosity or the like. Such a spin coating method includes, for example, formation of a photoresist film used in a semiconductor manufacturing process or the like, an interlayer insulating film such as SOG (spin on glass), an overcoat film (planarization film) or an alignment film in a liquid crystal device manufacturing process or the like. Is widely used for forming a protective film in the manufacturing process of an optical disk or the like.

However, in this spin coating method, since most of the supplied coating solution is scattered, it is necessary to supply a large amount of coating solution, and there is a disadvantage that the production cost is increased. In addition, since the substrate is rotated, the coating liquid flows from the inside to the outside due to centrifugal force, and the film thickness in the outer peripheral region tends to be thicker than the inside. .
In recent years, a technique for forming a thin film by applying a coating solution on a substrate by a so-called inkjet method has been proposed for these measures (see, for example, Patent Document 1). In this technique, an inkjet nozzle is linearly moved relative to a substrate by a relative moving means so that a coating liquid can be uniformly applied onto a square substrate.

In such a droplet discharge method such as the ink jet method, ink droplet (droplet) landing accuracy is improved, that is, the ink droplet (droplet) is more accurately positioned at a normal position as controlled by the control unit. It is essential to improve the accuracy of the obtained film pattern.
Based on this background, conventionally, particularly when the droplets ejected from the nozzles of the inkjet head (droplet ejection head) cause a flight curve and land out of the normal position, the following Such measures were taken.

As a first countermeasure, when a droplet ejected from a certain nozzle causes a flight curve, when performing overstrike at the same location, a droplet is ejected from another nozzle, thereby causing the flight curve to occur. Is prevented from forming a blank, and the deterioration of pattern accuracy due to flight bending is suppressed.
As a second countermeasure, when there is a nozzle that causes a flight curve, the position of the entire droplet discharge head including the nozzle is shifted from the original position to perform the discharge operation, thereby reducing the influence of the flight curve.

However, these countermeasures cannot completely eliminate the influence of the flight curve from the obtained film pattern. Therefore, when a higher pattern accuracy is required, the request cannot be sufficiently met.
Therefore, in order to ensure higher accuracy, nozzle information representing the ejection characteristics of each nozzle is created based on the landing state of the ink droplet (droplet) ejected from the nozzle, and the nozzle information is obtained based on the obtained nozzle information. An ink jet recording apparatus that controls driving is known (for example, see Patent Document 2).

According to this inkjet recording apparatus, the ejection operation of each nozzle is corrected based on the nozzle information, and ejection is performed under the conditions corrected in this way, so that high-quality images are formed with improved landing accuracy. can do.
JP-A-8-250389 JP 2004-58282 A

  However, as in the case of the ink jet recording apparatus (droplet discharge apparatus), nozzle information representing the discharge characteristics of each nozzle is created based on the landing state of the ink droplet (droplet) discharged from the nozzle, and the obtained nozzle When the nozzle drive is controlled based on the information, there are the following problems.

  If the ink used has high volatility or if the ink absorption of the recording medium on which ink droplets are landed is poor, after the ink is ejected and landed, the landing state such as the landing position and the landing diameter is measured. In the meantime, the solvent or dispersion medium in the landed ink evaporates (volatilizes). As the solvent or dispersion medium evaporates, the position of the ink droplet on the recording medium changes or the diameter of the ink droplet changes, and accurate data cannot be obtained. Therefore, even if the ejection operation is corrected based on the data obtained in this manner, the landing accuracy cannot be increased beyond a certain level.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the landing accuracy from each nozzle and thereby form a highly accurate film pattern, It is to provide a film pattern forming method used.

In order to achieve the above object, the droplet discharge device of the present invention comprises:
A droplet discharge head that has a plurality of nozzles and is provided above a stage on which a substrate is placed and discharges droplets from the nozzle onto the substrate, and relatively moves the droplet discharge head and the stage A detecting means for detecting a landing state of a droplet discharged from the droplet discharge head, and a discharge characteristic of each nozzle is detected based on a landing state of the droplet detected by the detecting means. A control means for controlling the ejection of the droplet ejection head based on the ejection characteristics; and a solvent or dispersion in a droplet that is disposed adjacent to the stage and ejected from the droplet ejection head on the stage. a steam supply means for supplying a steam of medium, the arranged positions different from the position where the substrate is placed on the stage, the droplet from the ejection head is ejected droplets that landed state by said detecting means Is characterized by comprising a testing board to be known, the.

  According to this droplet discharge device, since the vapor supply means for supplying the vapor of the solvent or the dispersion medium in the droplet discharged from the droplet discharge head is provided on the stage, for example, the liquid is applied on the substrate for inspection. After the droplets are ejected and landed, when the landing state such as the landing position and the landing diameter is measured, solvent (dispersion medium) vapor is supplied in advance on the stage by the vapor supply means, thereby landing the liquid. Evaporation (volatilization) of the solvent (dispersion medium) in the droplet (ink) can be suppressed. Therefore, it is possible to prevent the ejection characteristics of the nozzles from being detected inaccurately due to the evaporation (volatilization) of the solvent (dispersion medium), thereby preventing the landing accuracy from being lowered. . Therefore, a highly accurate film pattern can be formed even when the liquid material (ink) used is highly volatile or the substrate (recording medium) on which the droplet (ink droplet) is landed has poor liquid absorbency. Is possible.

In the droplet discharge device, the detection unit detects a landing position and a landing diameter of the droplet discharged from the droplet discharge head, and the control unit detects the droplet detected by the detection unit. A first difference between the landing position and the regular landing position of the liquid droplets, and a second difference between the landing diameter of the droplet detected by the detection means and the normal landing diameter, and the first difference and the It is preferable that a correction value for the landing position and the landing diameter of the droplet is determined based on the second difference, and discharge of the droplet discharge head is controlled based on the correction value.
In this way, it is possible to increase the accuracy of the landing position by controlling the discharge using a correction value based on the difference between the landing position of the droplet detected by the detecting means and the normal landing position, and By controlling the discharge using the correction value based on the difference between the landing diameter of the droplet detected by the detecting means and the normal landing diameter, the accuracy of the discharge amount can be increased.

Further, in the droplet discharge device, the control unit includes an evaporation correction unit that corrects a decrease in the landing diameter of the droplet detected by the detection unit due to evaporation of the solvent or the dispersion medium in the droplet. Is preferably provided.
In this case, the liquid material (ink) to be used is very volatile, and as described above, the solvent (dispersion medium) vapor is supplied from the landed droplets even though the solvent (dispersion medium) vapor is supplied by the vapor supply means. When the (dispersion medium) evaporates to some extent, the amount of decrease due to evaporation is corrected and the ejection of the droplet ejection head is controlled by the control means, so that the ejection accuracy can be further increased.

In the droplet discharge device, the vapor supply means includes a first container for flushing disposed in a flushing area on the side of the stage, and a droplet in a droplet discharged from the droplet discharge head. A second container storing the same solvent or dispersion medium as the solvent or dispersion medium; and a transfer means for transferring the solvent or dispersion medium in the second container into the first container. Is preferred.
If it does in this way, the 1st container of the flushing area normally provided as a part of apparatus, the 2nd container which stores the same solvent or dispersion medium as the solvent or dispersion medium in the above-mentioned droplet, and a transfer means Therefore, the size and complexity of the droplet discharge device can be suppressed, and the device configuration can be simplified.

In this droplet discharge device, the second container communicates with the first container, and the transfer means can move the second container up and down above the first container. It is preferable that it is constituted by lifting means that can be raised.
In this way, the solvent (or dispersion medium) stored in the second container can be transferred into the first container by its own weight, and thus the apparatus configuration of the transfer means is extremely simplified.

In this droplet discharge device, it is preferable that the stage, the flushing area, and the droplet discharge head are disposed in the same closed space.
In this way, by transferring the solvent (or dispersion medium) into the first container in the flushing area and evaporating there, the closed space can be made to have a substantially uniform vapor concentration. When the landing state such as the landing diameter is measured, the solvent (dispersion medium) vapor is supplied to the substrate by the vapor supply means in advance, thereby evaporating the solvent (dispersion medium) in the landed droplet (ink). (Volatilization) can be suppressed stably and reliably.

In the droplet discharge device, it is preferable that the first container is provided with heating means.
In this way, the evaporation rate of the solvent (or dispersion medium) transferred into the first container can be increased by heating with the heating means, and thus the solvent (or dispersion medium) on the substrate can be accelerated. The vapor concentration can be quickly increased to the desired concentration.

The film pattern forming method of the present invention is provided on a substrate from a droplet discharge head provided above a stage on which the substrate is placed and having a plurality of nozzles movable relative to the stage. In a method of forming a desired film pattern on a substrate by discharging droplets of material, prior to the formation of the desired film pattern , an inspection is performed at a position different from the position where the substrate is disposed on the stage. A step of detecting a landing state on the inspection substrate by discharging the droplets from the droplet discharge head and arranging each of the substrates based on the landing state of the droplets detected in the detection step; A control processing step of detecting a discharge characteristic of the nozzle and generating a control signal for controlling the discharge of the droplet discharge head based on the discharge characteristic; and controlling the discharge of the droplet discharge head based on the control signal. While And a film pattern forming process for forming a film pattern, wherein during the sensing step, the vapor supply means disposed adjacent to the stage, the same as the solvent or dispersion medium of said liquid droplets on said stage It is characterized by supplying a vapor of a solvent or a dispersion medium.

  According to this film pattern forming method, during the detection step, the same solvent or dispersion medium vapor as the solvent or dispersion medium in the droplets is supplied onto the stage. Evaporation (volatilization) of the solvent (dispersion medium) in the droplet (ink) can be suppressed. Therefore, as described above, it is possible to prevent the ejection characteristics of the nozzles from being detected inaccurately due to the evaporation (volatilization) of the solvent (dispersion medium), thereby preventing the landing accuracy from being lowered. can do. Therefore, a highly accurate film pattern can be formed even when the liquid material (ink) used is highly volatile or the substrate (recording medium) on which the droplet (ink droplet) is landed has poor liquid absorbency. Is possible.

In the film pattern forming method, it is preferable to supply the same solvent or dispersion medium vapor as the solvent or dispersion medium in the droplets onto the substrate also during the film pattern formation process.
In this way, it is possible to reduce the difference in the vapor concentration of the solvent (or dispersion medium) immediately above the central portion and immediately above the peripheral portion of the film made of droplets discharged onto the substrate. It is possible to prevent the film thickness of the peripheral part from becoming thicker than the film thickness of the central part due to the above, and the uniformity of the thickness of the entire film pattern to be obtained from being impaired.

Further, in the film pattern forming method, in the control processing step, the control signal may be corrected by correcting a decrease in the landing diameter of the droplet detected in the detection step due to evaporation of the solvent or the dispersion medium in the droplet. Is preferably created.
In this case, the liquid material (ink) to be used is very volatile, and as described above, the solvent (dispersion medium) is formed from the droplets that have landed even though the solvent (dispersion medium) vapor is supplied. If the liquid is evaporated to some extent, a control signal is created by correcting the decrease due to evaporation, and the ejection of the liquid droplet ejection head is controlled based on this control signal. Can do.

The present invention will be described in detail below.
FIG. 1 is a diagram showing an example of a droplet discharge device according to the present invention. In FIG. 1, reference numeral 30 denotes a droplet discharge device. The droplet discharge device 30 includes a base 31, a substrate moving unit 32, a head moving unit 33, a droplet discharge head 34, a liquid supply unit 35, a control device 40, and the like. The base 31 is provided with the substrate moving means 32 and the head moving means 33 constituting the moving means in the present invention.

The substrate moving means 32 is provided on the base 31 and has guide rails 36 arranged along the Y-axis direction. The substrate moving means 32 is configured to move the slider 37 along the guide rail 36 by, for example, a linear motor (not shown).
A stage 39 is fixed on the slider 37. Therefore, the substrate moving means 32 becomes the moving axis of the stage 39. This stage 39 is for positioning and holding the substrate (base) S. That is, this stage 39 has a known suction holding means (not shown), and the suction holding means is operated to hold the substrate S on the stage 39 by suction. The substrate S is accurately positioned and held at a predetermined position on the stage 39 by a positioning pin (not shown) of the stage 39, for example.

  A flushing area F for causing the droplet discharge head 34 to perform flushing on both sides of the substrate S on the stage 39, that is, on both sides in the movement direction (X-axis direction) of the droplet discharge head 34 described later, F is provided. In these flushing areas F, F, a first container 50 for receiving droplets from the droplet discharge head 34 by flushing is provided.

  The first container 50 is a rectangular parallelepiped formed long along the moving direction (Y-axis direction) of the stage 39, and accommodates therein a member (not shown) for absorbing droplets such as a sponge. Is. In addition, the first container 50 is provided with heating means such as a heater, so that the liquid material (ink) accommodated therein promotes evaporation of the solvent (or dispersion medium) component. It has become. Further, the first container 50 is formed so as to be inclined so that the bottom surface thereof is on one side, and in this embodiment, the side opposite to the droplet discharge head 34 is low. Then, the side surface (or bottom surface) on the lower side is connected to the second container 52 via the flexible tube 51.

  Since the second container 52 is connected to the first container 50 via the flexible tube 51, the inside thereof communicates with the first container 50. In addition, the second container 52 is placed on an elevating device 53 provided on the base 31 and can be moved up and down. In the present embodiment, the lifting device 53 includes an air cylinder 54, a rod 55 movably provided on the air cylinder 54, and a mounting plate 56 that is connected to the rod 55 and on which the second container 52 is mounted. Thus, the rod 55 can be moved up and down, so that the mounting plate 56 connected thereto can be moved up and down.

Based on such a configuration, the lifting device 53 holds the second container 52 so as to be lifted and lowered. Then, by raising the second container 52 higher than the first container 50, the liquid in the second container 52 can be transferred into the first container 50 via the flexible tube 51. . Thereby, the raising / lowering apparatus 53 functions as a transfer means in this invention. The elevating device 53, the first container 50, the flexible tube 51, and the second container 52 constitute the steam supply means of the present invention.
In this embodiment, a part of the upper surface of the base 31 is cut away to form an opening, and the lifting device 53 is configured so that the mounting plate 56 moves up and down in the opening.

The head moving means 33 includes a pair of mounts 33a and 33a standing on the rear side of the base 31, and a travel path 33b provided on the mounts 33a and 33a. It is arranged along the axial direction, that is, the direction orthogonal to the Y-axis direction of the substrate moving means 32. The travel path 33b is formed by having a holding plate 33c passed between the gantry 33a and 33a and a pair of guide rails 33d and 33d provided on the holding plate 33c. A carriage 42 on which the droplet discharge head 34 is mounted is movably held in the length direction 33d. The carriage 42 is configured to run on the guide rails 33d and 33d by the operation of a linear motor (not shown) or the like, thereby moving the droplet discharge head 34 in the X-axis direction.
Based on such a configuration, the head moving means 33 and the substrate moving means 32 function as moving means for relatively moving the droplet discharge head 34 and the stage 39. .

  Here, the carriage 42 can move in the length direction of the guide rails 33d, 33d, that is, in the X-axis direction, for example, in units of 1 μm, and such movement is controlled by the control device 40. ing. Therefore, as will be described later, when examining the ejection characteristics of the droplet ejection head 34 prior to ejection onto the substrate S, it is possible to eject droplets toward a preset position. Further, as described above, the positions of the first containers 50 and 50 are stored in the control device 40, so that the discharge of droplets for flushing by the droplet discharge head 34 is performed by the first container as will be described later. 50 is made surely.

  The droplet discharge head 34 is rotatably attached to the carriage 42 via an attachment portion 43. The mounting portion 43 is provided with a motor 44, and a support shaft (not shown) of the droplet discharge head 34 is connected to the motor 44. Based on such a configuration, the droplet discharge head 34 is rotatable in the circumferential direction. The motor 44 is also connected to the control device 40, whereby the droplet ejection head 34 is controlled by the control device 40 to rotate in the circumferential direction.

  Here, as shown in FIG. 2A, the droplet discharge head 34 is provided with, for example, a stainless steel nozzle plate 12 and a vibration plate 13, which are joined via a partition member (reservoir plate) 14. is there. A plurality of spaces 15 and a liquid reservoir 16 are formed between the nozzle plate 12 and the diaphragm 13 by the partition member 14. Each space 15 and the liquid reservoir 16 are filled with a liquid material, and each space 15 and the liquid reservoir 16 communicate with each other via a supply port 17. In addition, a plurality of nozzle holes 18 for injecting the liquid material from the space 15 are formed in the nozzle plate 12 in a state of being aligned vertically and horizontally. On the other hand, a hole 19 for supplying a liquid material to the liquid reservoir 16 is formed in the diaphragm 13.

  Further, a piezoelectric element (piezo element) 20 is joined to the surface of the diaphragm 13 opposite to the surface facing the space 15 as shown in FIG. The piezoelectric element 20 has a pair of electrodes 21 and is configured to bend and project outward when energized between the electrodes 21 and 21. The diaphragm 13 to which the piezoelectric element 20 is bonded in such a configuration is bent integrally with the piezoelectric element 20 at the same time so that the volume of the space 15 is increased. It is going to increase. Therefore, the liquid material corresponding to the increased volume flows into the space 15 from the liquid reservoir 16 through the supply port 17. Further, when energization to the piezoelectric element 20 is released from such a state, both the piezoelectric element 20 and the diaphragm 13 return to their original shapes. Accordingly, since the space 15 also returns to its original volume, the pressure of the liquid material in the space 15 rises, and the liquid material droplets 22 are ejected from the nozzle holes 18 toward the substrate.

In addition, the droplet discharge head 34 having such a configuration has a substantially rectangular bottom surface, and the nozzles 18 are aligned and arranged so that, for example, the length × width is 2 × 180. Here, although only one droplet discharge head 34 is shown in FIG. 1, the droplet discharge apparatus of the present invention is not limited to this, and may include a plurality of droplet discharge heads 34. Twelve droplet discharge heads 34 may be provided in parallel.
In addition to the piezo jet type using the piezoelectric element 20, for example, a method using an electrothermal transducer as an energy generating element can be adopted as the droplet discharge head 34.

The liquid supply means 35 includes a liquid supply source 45 for supplying a liquid material to the droplet discharge head 34 and a liquid supply tube 46 for supplying the liquid from the liquid supply source 45 to the droplet discharge head 34. .
Further, immediately above the stage 39, there is provided detection means 60 for detecting the landing state of the droplets ejected from the droplet ejection head 34. The detection means 60 is configured to be movable so as to be able to scan the inspection substrate A held on the stage 39. In the present embodiment, the detection means 60 includes a CCD camera.

  Here, as the inspection substrate A, the same material as that of the substrate S used for forming the film pattern is usually used, but a glass substrate is preferably used for simplicity. The inspection substrate A is provided with, for example, a reference line or point, and this reference line (reference point) is stored in the control device 40 as will be described later, and used for inspection of the ejection characteristics of each nozzle. It has become.

The detecting means 60 comprising the CCD camera inspects the traces of the droplets ejected from the nozzles of the droplet ejection head 34 on the inspection substrate A, and specifically, the nozzles. This is to detect the landing state of the droplets discharged from the nozzle, that is, the landing position and the landing diameter. Here, as a method for detecting the landing position and the landing diameter, the droplets that have landed on the inspection substrate A are photographed and recorded, and the obtained landing state data is sent to the control device 40.
The detection means 60 may be provided in the head moving means 33 together with the droplet discharge head 34 so as not to interfere with the droplet discharge head 34 so as to be movable.

  The control device 40 is a control means in the present invention, and is constituted by a CPU such as a microprocessor that controls the entire device, a computer having an input / output function of various signals, and the like. As shown in the block diagram of FIG. 3, the control device 40 controls the ejection operation by the droplet ejection head 34 and the movement operation by the substrate moving means 32 and the head moving means 33 and is detected by the detection means 60. The ejection characteristics of each nozzle of the droplet ejection head 34 are detected based on the landing state of the droplets, and the ejection of the droplet ejection head is controlled based on the ejection characteristics. The control device 40 also detects the position information of the droplet discharge head 34, that is, the position (X coordinate) of the droplet discharge head 34 on the guide rails 33d and 33d and the position (X coordinate) of each nozzle at that time. Is detected and memorized. Further, the lifting device 53 is also electrically connected to the control device 40, and the lifting and lowering of the mounting plate 56 of the lifting device 53 is also controlled by the control device 40.

Here, the control device 40 detects the ejection characteristics of each nozzle of the droplet ejection head 34 based on the droplet landing state detected by the detection means 60 as follows.
First, the control device 40 recognizes and stores the reference line (reference point) of the inspection substrate A as described above. This is done by, for example, receiving the position (X coordinate, Y coordinate) detected by the detection means 60 as a signal (data) and storing it. Alternatively, the position (X coordinate, Y coordinate) of the reference line (reference point) may be input by an operator.

  Next, prior to actual film pattern formation, droplets are ejected from each nozzle onto the inspection substrate A for detection of ejection characteristics of each nozzle of the droplet ejection head 34. At this time, the control device 40 recognizes the discharge position of each nozzle and issues a discharge instruction at that position. Therefore, when there is no flight bend and the discharge is made exactly as instructed and landed, the discharge position becomes the landing position on the inspection substrate A as it is. Therefore, the ejection position of each nozzle is stored as a normal landing position for each nozzle. The regular landing position is stored as a position with respect to the reference line (reference point) stored in advance.

  The landing diameter is determined experimentally or by simulation or the like from the discharge amount determined by the discharge signal (discharge voltage) to the piezoelectric element of each nozzle when it has landed on the inspection substrate A. This is stored as a normal landing diameter. The landing diameter stored in this way and the landing diameter detected by the detecting means 60 as will be described later are finally converted again to the discharge amount, and the discharge performance of each nozzle is determined with respect to the discharge amount. It shall be captured.

  Then, when the landing state of the droplet discharged from each nozzle onto the inspection substrate A, that is, data based on the detection result of the landing position and the landing diameter is sent from the detecting means 60, this data and the previously stored data are stored. Compare the impact position and impact diameter. That is, the difference (first difference) between the landing position of the droplet detected by the detecting unit 60 and the regular landing position is obtained, and the landing diameter of the droplet detected by the detecting unit 60 The difference (second difference) from the normal landing diameter is obtained. These differences (the first difference and the second difference) are recognized as the discharge characteristics of each nozzle, that is, the discharge variation of each nozzle, and the discharge position and the discharge are performed so that regular discharge is performed without this variation. A correction value for the control value for the discharge amount is determined.

When the ejection characteristics of each nozzle of the droplet ejection head 34 are detected in this way and a correction value for ejection is determined for each nozzle, the control device 40 determines the ejection characteristics of the droplet ejection head 34 based on this correction value. In order to perform discharge, that is, discharge from each nozzle, the discharge control is performed.
Further, as shown in FIG. 3, the control device 40 includes an evaporation that corrects a decrease in the landing diameter of the droplet detected by the detecting means 60 due to evaporation of the solvent or dispersion medium in the droplet. Correction means 61 is provided.

  Such a droplet discharge device 30 is provided in a chamber 41 indicated by a two-dot chain line in FIG. The chamber 41 is closed from the outside to be a closed space, and is provided with a pressure reducing means such as a vacuum pump so that the internal pressure can be controlled. Needless to say, the chamber 41 is provided with a door so that it can enter and exit.

Next, a film pattern forming method using the droplet discharge device 30 having such a configuration will be described.
First, the inspection substrate A and the substrate (substrate) S for film pattern formation are set at predetermined positions on the stage 39, respectively. Here, the substrate S is a base for forming a film pattern made of various functional materials, and various substrates such as glass and silicon are adopted depending on the type of the film pattern. Moreover, what formed various components, such as TFT, wiring, and an insulating layer, on such a board | substrate can be used. In the present invention, including such a substrate and those on which various components are formed, these are referred to as a substrate. Here, an example in which the inspection substrate A and the substrate (substrate) S for film pattern formation are set on the stage 39 at the same time will be described. However, the discharge performance of the droplet discharge head 34 using the inspection substrate A will be described. Then, the inspection substrate A may be removed, and the substrate (base body) S may be set on the stage 39, and a film pattern may be formed thereon.

Next, prior to discharging the film pattern forming material (liquid material) from the droplet discharge head 34 onto the substrate S, the control device 40 controls the reference line (reference point) of the inspection substrate A as described above. ) And memorize it.
Subsequently, droplets are ejected from the nozzles onto the inspection substrate A in order to detect ejection characteristics of the nozzles of the droplet ejection head 34. Here, in the droplet discharge head 34, the nozzles are aligned and arranged so that the length × width is 2 × 180 as described above, and the droplets are discharged simultaneously from all the nozzles. When droplets are ejected from all the nozzles onto the inspection substrate A in this way, the landing state of each droplet on the inspection substrate A is detected by the detection means 60 (detection step). Note that the detection of the landing state by the detection means 60 is performed by photographing and recording the landing state in order from one side of the 180 nozzle rows aligned in the horizontal direction in this example.

  Prior to this droplet discharge, it is preferable to perform flushing. This flushing is performed particularly in a case where the liquid material discharged from the nozzle is not continuously discharged, particularly when the solvent or dispersion medium in the discharged liquid material is highly volatile. Volatilization causes an increase in viscosity. In severe cases, the liquid material solidifies, dust adheres to it, and the nozzle opening is clogged due to air bubbles and other problems. Is to do.

  Further, during such flushing, the mounting plate 56 is lowered in advance by the elevating device 53 so that the second container 52 becomes lower than the first container 50 as shown in FIG. Keep it. Then, the liquid material L discharged into the first container 50 by the flushing is absorbed by a member such as a sponge provided in the first container 50, and a part of the solvent (dispersion medium) is volatilized (evaporated). ) And the remainder reaches the bottom of the first container 50. The liquid material L reaching the bottom is transferred to the second container 52 through the flexible tube 51.

  It should be noted that the amount of liquid material discharged by flushing is not so large, and is therefore usually not sufficient for the vapor generation of a solvent (dispersion medium) described later. In such a case, only the liquid material L itself, which is a thin film forming material, or the solvent (dispersion medium) component in the liquid material is placed in the second container 52 in advance.

  The landing state detected by the detecting means 60 is determined as a landing position and a landing diameter for each nozzle by analyzing the data obtained by shooting and recording by a known method by the control device 40. It is stored in the control device 40. The landing position is usually defined by the center (center of gravity). In particular, this landing position is stored as a position with respect to the reference line (reference point) stored in advance in the same manner as the normal landing position described above.

  Separately from this, the control device 40 stores the respective normal landing positions and normal landing diameters of the respective nozzles as described above. Then, the difference between the landing position of the droplet detected by the detecting means 60 and the regular landing position is obtained, and further, the difference between the landing diameter of the droplet detected by the detecting means 60 and the regular landing diameter is determined. By obtaining the difference, the ejection characteristics of each nozzle are detected as described above. This discharge characteristic is recognized as the discharge variation of each nozzle as described above. And the correction value with respect to the control value about a discharge position and discharge amount is determined so that regular discharge may be performed without this variation (control processing step).

  When the ejection characteristics of each nozzle of the droplet ejection head 34 are detected in this way and the correction value for ejection is determined for each nozzle, the control device 40 performs this correction upon ejection for forming a film pattern to be described later. Based on the value, discharge control is performed to discharge the droplet discharge head 34, that is, discharge from each nozzle.

Further, when determining the correction value, particularly in the detection step, vapor of the same solvent (dispersion medium) as the solvent (dispersion medium) in the droplet is applied on the stage 39, that is, on the inspection substrate A. The supply is as follows.
The elevating device 53 is operated to raise the mounting plate 56 so that the second container 52 is positioned higher than the first container 50 as shown in FIG. Then, the liquid material or the solvent (dispersion medium) component stored in the second container 52 is transferred into the first container 50 through the flexible tube 51. In particular, the solvent (dispersion medium) evaporates in the first container 50, thereby increasing the vapor concentration of the solvent (dispersion medium) on the inspection substrate A.
Here, when the volatility of the solvent (dispersion medium) in the liquid material to be used is low, the liquid material or the solvent (dispersion medium) is heated by the heating means provided in the first container 50, and the solvent (or The evaporation rate of the dispersion medium) may be increased.

  In this way, the solvent (dispersion medium) is evaporated from the inside of the first container 50, and the vapor concentration of the solvent (dispersion medium) on the inspection substrate A is sufficiently increased. Evaporation (volatilization) of the solvent (dispersion medium) in the landed droplets can be suppressed. Therefore, the impact diameter is detected to be particularly small due to the evaporation (volatilization) of the solvent (dispersion medium), so that the ejection characteristics of the nozzle are detected inaccurately. As a result, the impact accuracy when ejected from this nozzle is improved. It can prevent that it falls.

  Further, the liquid material to be used is very volatile, and although the solvent (dispersion medium) vapor is supplied onto the inspection substrate A as described above, the solvent (dispersion medium) from the landed droplets. May evaporate to some extent. In such a case, the landing diameter of the droplet detected by the detecting unit 60 is decreased by the evaporation correction unit 61, for example, due to evaporation of the solvent (dispersion medium) in the droplet as follows. It is preferable to correct the minutes.

FIG. 5 is a flowchart of correction by the evaporation correction means 61.
First, for the nozzle # 1 in the first position in the row of 180 nozzles in the droplet discharge head 34, the landing diameter is obtained by the detection means 60 and the control means 40, and this is corrected by the evaporation correction of the control means 40. The data is stored in the means 61 (step 1; indicated as ST1 in FIG. 5).

  Next, the nozzle # 2 at the second position, the nozzle # 3 at the third position, the nozzle # 4, the nozzle # 5,..., And their landing diameters are sequentially obtained (step 2). When the landing diameters of all the nozzles (180) are obtained, the landing diameters of the droplets ejected from the nozzle # 1 at the first position are obtained again and stored in the evaporation correction means 61 ( Step 3). Then, from the landing diameter d1 (2) of the nozzle # 1 stored here and the landing diameter d1 (1) of the nozzle # 1 stored previously, the respective volumes S1 (1) of the liquid droplets that have landed (discharged). , S1 (2) is obtained by simulation based on calculation or experiment.

Thereby, the evaporation amount (volatilization amount) Sk of the droplet between the first detection and the second detection by the detection means 60 is S1 (1) -S1 (2).
In addition, regarding the detection of the landing diameter for each nozzle, the time required for this detection is assumed to be constant for each nozzle.
Then, the amount SNk of the nozzle (#N) at the Nth position in the nozzle where the solvent (dispersion medium) in the droplet immediately after landing is reduced by evaporation is represented by Sk × (N / 180). Therefore, the decrease SNk due to evaporation is used as a correction value, and the volume obtained from the detected landing diameter is corrected (step 4).
That is, for the nozzle #N at the Nth position in the nozzle, assuming that the volume based on the detected landing diameter is SN (1), the correction value SNk {= Sk × (N / 180)} is used for this. By adding, the true volume after correction is represented by SN (1) + Sk × (N / 180).

In this way, when creating the control signal for controlling the ejection of all the nozzles of the droplet ejection head 34, the droplet landing diameter detected in the detection step, particularly the solvent (dispersion in the droplet). The amount reduced by evaporation of the medium can be corrected.
The film pattern forming material (liquid material) is discharged onto the substrate S while controlling the discharge of each nozzle of the droplet discharge head 34 on the basis of the control signal thus created. The film pattern can be formed (film pattern forming process).

Here, the ejection control of each nozzle of the droplet ejection head 34 based on the control signal is specifically performed as follows.
As for the landing position, the discharge position of each nozzle of the droplet discharge head 34 is corrected so as to eliminate the difference from the normal landing position, and discharge is performed from there.
As for the discharge amount based on the landing diameter, the discharge amount of each nozzle of the droplet discharge head 34 is corrected so as to eliminate the difference from the normal discharge amount, and the discharge is performed.

  In this way, the droplet ejection apparatus 30 of the present invention can form a highly accurate film pattern by correcting the landing position and the ejection amount (landing diameter) and performing the ejection operation. Further, since the same solvent as the solvent (dispersion medium) in the droplet or the vapor of the dispersion medium is supplied onto the inspection substrate A (stage 39) particularly during the detection process, the liquid that has landed on the substrate A The evaporation (volatilization) of the solvent (dispersion medium) in the droplets can be suppressed. Therefore, it is possible to prevent the ejection characteristics of the nozzles from being detected inaccurately, thereby reducing the landing accuracy when ejected. Therefore, a highly accurate film pattern can be formed even when the liquid material (ink) to be used is highly volatile, or when the liquid absorption property of the substrate on which the droplets are landed is poor.

  Further, in this droplet discharge device 30, a second container 52 is usually connected to a first container 50 in a flushing area provided as a part of the apparatus, and a solvent ( Since the vapor supply means is configured only by providing the transfer means (elevating device 53) for transferring the dispersion medium) into the first container 50, the apparatus configuration can be reduced while suppressing the increase in size and complexity of the apparatus. It is possible to simplify the structure, thereby suppressing an increase in apparatus cost.

When the film pattern forming material (liquid material) is discharged onto the substrate S while controlling the discharge from each nozzle of the droplet discharge head 34, the stage 30, That is, it is preferable to supply vapor of the same solvent (dispersion medium) as the solvent (dispersion medium) in the liquid material onto the substrate S.
In this way, the difference in the solvent (dispersion medium) vapor concentration between the central portion and the peripheral portion of the film made of droplets discharged onto the substrate S can be sufficiently reduced. It can be prevented that the film thickness of the peripheral part becomes thicker than the film thickness of the central part due to the difference, and the uniformity of the thickness of the entire film pattern to be obtained is impaired.

The droplet discharge device of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist of the present invention. For example, the lifting / lowering device 53 that lifts and lowers the second container 52 is used as the transfer means in the steam supply means. Instead, the liquid in the second container 52 is removed from the first container using a liquid feed pump. 50 may be transferred.
In addition, the first container 50 is provided in the flushing area on both sides of the moving axis of the stage, and the second container 52 is connected to the first container 50. However, the first container 50 is provided only in the flushing area on one side. You may do it.

Next, an example in which such a thin film forming method using the droplet discharge device 30 is applied to a method for manufacturing an organic EL device will be described.
FIG. 6 is a side sectional view of an organic EL device in which some components are manufactured by the droplet discharge device 30. First, a schematic configuration of the organic EL device will be described.
As shown in FIG. 6, this organic EL device 301 is composed of a substrate 311, a circuit element part 321, a pixel electrode 331, a bank part 341, a light emitting element 351, a cathode 361 (counter electrode), and a sealing substrate 371. A wiring of a flexible substrate (not shown) and a driving IC (not shown) are connected to the EL element 302. The circuit element portion 321 is formed on the substrate 311, and a plurality of pixel electrodes 331 are aligned on the circuit element portion 321. Bank portions 341 are formed in a lattice shape between the pixel electrodes 331, and light emitting elements 351 are formed in the recess openings 344 generated by the bank portions 341. The cathode 361 is formed on the entire upper surface of the bank portion 341 and the light emitting element 351, and a sealing substrate 371 is laminated on the cathode 361.

  The manufacturing process of the organic EL device 301 including the organic EL element includes a bank part forming step for forming the bank part 341, a plasma processing step for appropriately forming the light emitting element 351, and a light emitting element formation for forming the light emitting element 351. A process, a counter electrode forming process for forming the cathode 361, and a sealing process for stacking and sealing the sealing substrate 371 on the cathode 361.

  The light emitting element forming step is to form the light emitting element 351 by forming the hole injection layer 352 and the light emitting layer 353 on the concave opening 344, that is, the pixel electrode 331. The hole injection layer forming step and the light emitting layer forming step It is equipped with. The hole injection layer forming step includes a first discharge step of discharging a first composition (liquid material) for forming the hole injection layer 352 onto each pixel electrode 331, and the discharged first composition. And the first drying step of forming the hole injection layer 352, and the light emitting layer forming step includes supplying a second composition (liquid material) for forming the light emitting layer 353 to the hole injection layer 352. It has the 2nd discharge process discharged above, and the 2nd drying process which forms the light emitting layer 353 by drying the discharged 2nd composition.

In the light emitting element forming step, the droplet discharge device 30 is used in the first discharging step in the hole injection layer forming step and the second discharging step in the light emitting layer forming step.
Also in the manufacture of the organic EL device 301, the ejection performance of each nozzle is detected in advance before ejection for forming each film pattern, and ejection of the droplet ejection head 34 is controlled based on the detected ejection performance. Thus, the hole injection layer 352 and the light emitting layer 353 obtained as a film pattern can be formed with extremely high accuracy. Therefore, when the hole injection layer 352 and the light emitting layer 353 have a highly accurate pattern, the organic EL device 301 having good light emission characteristics can be manufactured.

The organic EL device 301 manufactured in this way is suitably used as a display unit of various electronic devices such as a mobile phone, a notebook personal computer, a PDA (Personal Data Assistance), and a wristwatch type electronic device.
The film pattern forming method of the present invention can be applied to the formation of various film patterns such as a wiring pattern and a color filter in a liquid crystal display device in addition to the hole injection layer and the light emitting layer in the organic EL device. .

It is a perspective view which shows schematic structure of the droplet discharge apparatus of this invention. (A), (b) is a figure for demonstrating schematic structure of a droplet discharge head. It is a block diagram for demonstrating the structure concerning a control apparatus. (A), (b) is a figure for demonstrating operation | movement of a 2nd container. It is a flowchart of the correction | amendment by an evaporation correction | amendment means. It is a sectional side view of an organic EL device.

Explanation of symbols

30 ... droplet discharge device, 32 ... substrate moving means (moving means),
33 ... Head moving means (moving means), 34 ... Droplet discharge head, 39 ... Stage,
40 ... Control device (control means), 41 ... Chamber, 50 ... First container,
51 ... Flexible tube, 52 ... Second container, 53 ... Elevating device (transfer means),
60: Detection means, A: Substrate for inspection, F: Flushing area, S: Substrate (base)

Claims (10)

A droplet discharge head that has a plurality of nozzles and is provided above a stage on which the substrate is placed and discharges droplets from the nozzle onto the substrate;
Moving means for relatively moving the droplet discharge head and the stage;
Detecting means for detecting a landing state of a droplet discharged from the droplet discharge head;
Control means for detecting ejection characteristics of each nozzle based on the landing state of the droplets detected by the detection means, and controlling ejection of the droplet ejection head based on the ejection characteristics;
A vapor supply means that is disposed adjacent to the stage and supplies a vapor of a solvent or a dispersion medium in droplets ejected from the droplet ejection head onto the stage;
An inspection substrate disposed on a position different from the position where the substrate is disposed on the stage, and droplets are ejected from the droplet ejection head and the landing state thereof is detected by the detection means . A droplet discharge apparatus characterized by the above. The detection means detects a landing position and a landing diameter of a droplet discharged from a droplet discharge head,
The control means includes a first difference between a landing position of the droplet detected by the detecting means and a normal landing position, and a first difference between the landing diameter of the droplet detected by the detecting means and the normal landing diameter. 2 is determined, a correction value of the landing position and the landing diameter of the droplet is determined based on the first difference and the second difference, and the droplet discharge head of the droplet discharge head is determined based on the correction value. The droplet discharge device according to claim 1, wherein the droplet discharge device is configured to control discharge.   The control means includes an evaporation correction means for correcting an amount of decrease in the landing diameter of the droplet detected by the detection means due to evaporation of the solvent or the dispersion medium in the droplet. The droplet discharge device according to claim 1 or 2.   The vapor supply means includes a first flushing container disposed in a flushing area on the side of the stage, and the same solvent or dispersion medium as the solvent or dispersion medium in the droplets ejected from the droplet ejection head. And a transfer means for transferring a solvent or a dispersion medium in the second container into the first container. The droplet discharge device according to any one of the above. The second container communicates with the first container;
5. The liquid droplet ejection apparatus according to claim 4, wherein the transfer means is constituted by an elevating means capable of raising and lowering the second container above the first container.   6. The liquid droplet ejection apparatus according to claim 4, wherein the stage, the flushing area, and the liquid droplet ejection head are disposed in the same closed space.   The droplet discharge device according to claim 4, wherein the first container is provided with a heating unit. A droplet of a functional material is ejected onto a substrate from a droplet ejection head that is provided above a stage on which the substrate is placed and has a plurality of nozzles that can move relative to the stage. In a method of forming a desired film pattern on the top,
Prior to the formation of the desired film pattern , an inspection substrate is disposed at a position different from the position where the substrate is disposed on the stage, and the liquid droplets are ejected from the liquid droplet ejection head to perform the inspection. A detection process for detecting the landing state on the substrate ;
A control processing step of detecting a discharge characteristic of each nozzle based on the landing state of the droplet detected in the detection step and creating a control signal for controlling discharge of the droplet discharge head based on the discharge characteristic; ,
A film pattern forming process for forming the desired film pattern while controlling the discharge of the droplet discharge head based on the control signal,
During the detection step, a vapor of a solvent or dispersion medium that is the same as the solvent or dispersion medium in the droplets is supplied onto the stage from a vapor supply means disposed adjacent to the stage. Pattern formation method.   9. The film pattern forming method according to claim 8, wherein the same solvent or dispersion medium vapor as the solvent or dispersion medium in the droplets is supplied onto the substrate also during the film pattern formation process.   In the control processing step, the control signal is generated by correcting a decrease in the landing diameter of the droplet detected in the detection step due to evaporation of a solvent or a dispersion medium in the droplet. Item 10. The film pattern forming method according to Item 8 or 9.

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