JP2009148694A - Liquid material discharge method, color filter manufacturing method, organic EL element manufacturing method - Google Patents

Abstract

Disclosed is a liquid material discharge method capable of stably applying a substantially constant amount of liquid material as droplets for each film formation region on a substrate, a method of manufacturing a color filter using the liquid material discharge method, and To provide a method for producing an organic EL element
In the method for discharging a liquid material according to the present application example, a plurality of scans for relatively moving a plurality of nozzles 52 and a substrate are performed a plurality of times, and a plurality of film forming regions 3r ₁ , 3r ₂ , 3r arranged on the substrate. ₃ is a liquid discharge method including a discharge step of discharging a liquid as droplets D from a plurality of nozzles 52. The discharge step includes a selection pattern of nozzles 52 that discharge droplets D in a plurality of scans. The combination is assumed to be the same for each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ .
[Selection] Figure 9

Description

  The present invention relates to a method for discharging a liquid containing a functional material, a method for manufacturing a color filter, and a method for manufacturing an organic EL element.

  As a method of discharging a liquid material containing a functional material, a nozzle to be used is selected from a nozzle row composed of a plurality of nozzles so that the liquid material is not discharged simultaneously from the adjacent nozzles on the film formation region of the discharge target object. A first discharge process for performing discharge, and a second discharge process for performing discharge by selecting a different combination of nozzles from the first discharge process so that the liquid material is not discharged simultaneously from adjacent nozzles in the film formation region Are known (Patent Document 1).

  The above-described ejection method is a method in which a plurality of nozzles are driven in a time-sharing manner, and is intended to reduce variation in the ejection amount between adjacent nozzles by devising a way of selecting the nozzles.

  Further, as another liquid material discharge method, a substrate provided with a plurality of discharged portions and a discharge head capable of discharging a functional liquid as liquid droplets are relatively scanned a plurality of times. The entire discharge scan for discharging the functional liquid to the entire area of each discharged portion is performed at least once for each discharged portion, and at least a part of the peripheral portion of the discharged portion is avoided in the scan other than the entire discharged scan. A droplet discharge method for performing partial discharge scanning for discharging a functional liquid is known (Patent Document 2).

  In the droplet discharge method, it is possible to suppress mixing of different types of functional liquids by separately performing the entire discharge scan and the partial discharge scan.

JP 2007-152339 A JP 2007-29946 A

  It is conceivable to apply the discharge method of Patent Document 1 to the droplet discharge method of Patent Document 2. However, depending on the relative positional relationship between the plurality of nozzles and the plurality of discharged portions in the partial discharge scan, there is a problem that it becomes difficult to select the nozzles so that partial discharge is performed in all of the discharged portions. .

  In addition, the amount of liquid droplets discharged from each nozzle is influenced by electrical and mechanical crosstalk between nozzles, and it is basically difficult to make them completely the same regardless of the nozzle selection method. There are challenges.

  On the other hand, when the droplet discharge method is used industrially, it is required to apply a functional liquid (liquid material) to the discharge target portion with a stable application amount even if the droplet discharge amount varies to some extent.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  [Application Example 1] In the liquid material discharge method according to this application example, scanning for relatively moving a plurality of nozzles and a substrate is performed a plurality of times, and the plurality of nozzles are applied to a plurality of film formation regions arranged on the substrate. A discharge method for discharging a liquid material having a discharge step of discharging the liquid material as droplets, wherein the discharge step includes a combination of nozzle selection patterns for discharging the droplets in the plurality of scans. Each is the same.

  When a liquid material is discharged as droplets from a plurality of nozzles using the droplet discharge method (inkjet method), the discharge of droplets discharged from each nozzle due to crosstalk (electrical or mechanical) between the nozzles. The amount varies. Variation in the discharge amount of the liquid droplets affects the application amount of the discharged liquid material. Therefore, how to select a nozzle that discharges droplets among a plurality of nozzles affects the quantitative accuracy. According to this method, even if the discharge amount of the liquid droplets discharged to the film formation region varies depending on the nozzle selection pattern (selection method) for each scan, the combination of the nozzle selection patterns in a plurality of scans is the same. Therefore, when a plurality of scans are completed, a substantially constant amount of liquid material can be stably discharged for each film formation region.

Application Example 2 In the liquid material discharge method according to the application example described above, in the discharge process, the nozzle selection pattern for each film formation region may be different for each scanning.
Depending on the relative positional relationship between the plurality of nozzles in scanning and the plurality of film formation regions arranged on the substrate, the same number of nozzles is not necessarily applied to each film formation region. According to this method, the nozzle selection pattern for each film formation region is made different for each scan in response to the relative positional relationship between the plurality of nozzles and the plurality of film formation regions in the scan. When scanning is completed, a substantially constant amount of liquid material can be stably ejected for each film formation region.

Application Example 3 In the liquid material discharge method according to the application example described above, it is preferable that in the discharge process, the nozzle selection pattern for each film formation region is constant for each scan.
According to this method, by setting the nozzle selection pattern for each film formation region constant for each scan, the ejection characteristics of the selected nozzle can be stabilized for each scan. Therefore, a substantially constant amount of liquid material can be discharged more stably for each film formation region.

Application Example 4 In the liquid material discharge method according to the application example described above, it is more preferable that in the discharge step, the selection pattern of the nozzles for each film formation region is constant over the plurality of scans.
According to this method, since the ejection characteristics of the nozzles selected over a plurality of scans are stabilized, a substantially constant amount of liquid material is formed for each film formation region as compared with the case where the nozzle selection pattern changes for each scan. Can be discharged more stably.

Application Example 5 In the liquid material discharge method according to the application example described above, the discharge step is performed by applying one of a plurality of periodically generated drive waveforms to the selected nozzle drive unit. A droplet is ejected.
According to this method, droplets are ejected from a selected nozzle among a plurality of nozzles by time-division driving.
Therefore, even if there are a plurality of nozzles selected for each film formation region, the driving waveform is not applied to the driving means for the nozzles simultaneously. Therefore, it is possible to reduce variations in the discharge amount of the liquid droplets discharged due to electrical crosstalk between the nozzles. That is, a substantially constant amount of liquid material can be stably discharged with reduced variations.

Application Example 6 In the liquid material discharge method according to the application example described above, the discharge step is the same as the drive unit of the adjacent nozzles among the plurality of nozzles selected by the nozzle selection pattern in the scanning. It is preferable that no drive waveform is applied and the selection for each of the plurality of drive waveforms is substantially equal.
According to this method, the drive waveform applied to the selected plurality of nozzles is not biased to a specific drive waveform, and the plurality of drive waveforms are used almost uniformly in scanning. Therefore, even if the number of selected nozzles increases and the drive waveform becomes dull, the dullness between the plurality of drive waveforms can be made uniform. That is, variations in the discharge amount of droplets due to the dullness of the drive waveform can be made uniform, and a substantially constant amount of liquid material can be stably discharged for each film formation region.

Application Example 7 In the liquid material discharge method according to the application example described above, the discharge step uses at least one nozzle that is close to the center of the film formation region among the nozzles applied to each film formation region in the scanning. Is preferred.
According to this method, all droplets to be ejected can be landed near the center of the film formation region. Therefore, it is possible to stably discharge a substantially constant amount of liquid material by reducing the occurrence of droplets that do not land on the film formation area due to the bending of the flight of droplets or unnecessary droplets landing. Can do.

  Application Example 8 A color filter manufacturing method according to this application example is a method of manufacturing a color filter having a plurality of colored layers in a plurality of film formation regions on a substrate, and the liquid material ejection method according to the application example described above , A discharge step of discharging a plurality of color liquids containing a coloring layer forming material to the plurality of film formation regions, and a film formation step of solidifying the discharged liquid material to form the plurality of color layers And.

  According to this method, the liquid material discharge method of the above application example is used. Accordingly, in the discharging process, a substantially constant amount of the liquid material of the corresponding color is stably discharged to the film formation region of the same color, and in the film formation step, a colored layer having substantially the same film thickness in the film formation region of the same color. Can be formed. That is, a color filter having stable optical characteristics for each color can be manufactured.

  [Application Example 9] A method for manufacturing an organic EL element according to this application example is a method for manufacturing an organic EL element having a functional layer including a light emitting layer in a plurality of film formation regions on a substrate. A discharge step of discharging a liquid material containing a light emitting layer forming material to the plurality of film forming regions, and a film forming step of solidifying the discharged liquid material to form the light emitting layer. It is characterized by having.

  According to this method, the liquid material discharge method of the above application example is used. Therefore, a substantially constant amount of liquid material can be stably discharged in the film formation region in the discharge step, and a light emitting layer having a substantially equivalent film thickness can be formed in each film formation region in the film formation step. That is, an organic EL element having stable light emission characteristics can be manufactured.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described with reference to the drawings.

(Embodiment 1)
<Droplet ejection device>
First, a droplet discharge device capable of discharging a liquid as droplets will be described with reference to FIGS. FIG. 1 is a schematic perspective view showing the configuration of the droplet discharge device.

  As shown in FIG. 1, the droplet discharge device 10 includes a workpiece moving mechanism 20 that moves the workpiece W in the main scanning direction (X-axis direction), and a head that moves the head unit 9 in the sub-scanning direction (Y-axis direction). And a moving mechanism 30.

The workpiece moving mechanism 20 includes a pair of guide rails 21, a moving table 22 that moves along the pair of guide rails 21, and a stage on which the workpiece W disposed on the moving table 22 via the rotating mechanism 6 is placed. And 5.
The moving table 22 is moved in the main scanning direction by an air slider and a linear motor (not shown) provided inside the guide rail 21. The moving table 22 is provided with an encoder 12 (see FIG. 4) as a timing signal generator.
The encoder 12 reads a scale of a linear scale (not shown) arranged in parallel with the guide rail 21 in accordance with the relative movement of the moving base 22 in the main scanning direction, and generates an encoder pulse as a timing signal.
The stage 5 can suck and fix the workpiece W, and the rotation mechanism 6 can accurately adjust the reference axis in the workpiece W in the main scanning direction and the sub-scanning direction. In addition, arrangement | positioning of the encoder 12 is not restricted to this, For example, when the moving base 22 is comprised so that it may move relatively to an X-axis direction along a rotating shaft, and the drive part which rotates a rotating shaft is provided, The encoder 12 may be provided in the drive unit. Examples of the drive unit include a servo motor.

The head moving mechanism 30 includes a pair of guide rails 31 and a moving table 32 that moves along the pair of guide rails 31. The moving table 32 is provided with a carriage 8 suspended via a rotation mechanism 7.
A head unit 9 on which a plurality of droplet discharge heads 50 (see FIG. 2) is mounted is attached to the carriage 8.
Further, a liquid material supply mechanism (not shown) for supplying a liquid material to the droplet discharge heads 50 and a head driver 48 for performing electrical drive control of the plurality of droplet discharge heads 50 (see FIG. 4). And are provided.
The moving table 32 moves the carriage 8 in the Y-axis direction so that the head unit 9 is disposed opposite to the workpiece W.

In addition to the above-described configuration, the droplet discharge device 10 has a maintenance mechanism that performs maintenance such as nozzle clogging of a plurality of droplet discharge heads 50 mounted on the head unit 9 and removal of foreign matters and dirt on the nozzle surface. The plurality of droplet discharge heads 50 are disposed at a position facing the droplet discharge heads 50.
In addition, a weight measuring mechanism having a measuring instrument such as an electronic balance that receives the liquid discharged from each droplet discharge head 50 and measures the weight thereof is provided. In FIG. 1, the maintenance mechanism and the weight measuring mechanism are not shown.

  FIG. 2 is a schematic view showing the structure of the droplet discharge head. FIG. 4A is a perspective view, and FIG. 4B is a plan view showing a nozzle arrangement state.

  As shown in FIG. 2A, the droplet discharge head 50 is a so-called two-unit type, a liquid material introduction portion 53 having two connection needles 54, and a head substrate stacked on the introduction portion 53. 55 and a head main body 56 which is disposed on the head substrate 55 and has a liquid-in-head flow path formed therein. The connection needle 54 is connected to the above-described liquid material supply mechanism (not shown) via a pipe, and supplies the liquid material to the flow path in the head. The head substrate 55 is provided with two connectors 58 connected to the head driver 48 (see FIG. 4) via a flexible flat cable (not shown).

  The head main body 56 includes a pressurizing unit 57 having a cavity made of a piezoelectric element, and a nozzle plate 51 in which two nozzle rows 52a and 52b are formed in parallel to each other on the nozzle surface 51a.

  As shown in FIG. 2B, in the two nozzle rows 52a and 52b, a plurality (180) of nozzles 52 are arranged at substantially equal intervals with a pitch P1, and the pitch P2 is shifted by half of the pitch P1. In this state, the nozzle plate 51 is disposed. In this case, the pitch P1 is approximately 141 μm. Accordingly, when viewed from the direction orthogonal to the nozzle row 52c, 360 nozzles 52 are arranged at a nozzle pitch of approximately 70.5 μm. In the following description, the interval between the nozzles 52 is the nozzle pitch P2. The diameter of the nozzle 52 is approximately 27 μm.

  In the droplet discharge head 50, when a drive signal as an electric signal is applied from the head driver 48 to the piezoelectric element, the volume of the cavity of the pressurizing unit 57 fluctuates. The liquid material can be discharged as droplets from the nozzle 52 under pressure.

  The driving means in the droplet discharge head 50 is not limited to a piezoelectric element. An electromechanical conversion element that displaces a diaphragm as an actuator by electrostatic adsorption, or an electrothermal conversion element (thermal method) that heats a liquid material and discharges it from a nozzle 52 as droplets may be used.

  FIG. 3 is a schematic plan view showing the arrangement of the droplet discharge heads in the head unit. Specifically, it is a view seen from the side facing the workpiece W.

  As shown in FIG. 3, the head unit 9 includes a head plate 9a on which a plurality of droplet discharge heads 50 are disposed. A total of six droplet ejection heads 50, that is, a head group 50 </ b> A composed of three droplet ejection heads 50 and a head group 50 </ b> B composed of three droplet ejection heads 50 are mounted on the head plate 9 a. In this case, the head R1 (droplet discharge head 50) of the head group 50A and the head R2 (droplet discharge head 50) of the head group 50B discharge the same type of liquid. The same applies to the other heads G1 and G2, and heads B1 and B2. That is, it has a configuration capable of discharging three different liquid materials.

The drawing width that can be drawn by one droplet discharge head 50 is L _0, and this is the effective length of the nozzle row 52c. Hereinafter, the nozzle row 52 c refers to a configuration including 360 nozzles 52.

In this case, in the head R1 and the head R2, the nozzle rows 52c adjacent to each other when viewed from the main scanning direction (X-axis direction) are continuously arranged with one nozzle pitch in the sub-scanning direction (Y-axis direction) orthogonal to the main scanning direction. Thus, they are arranged in parallel in the main scanning direction. Therefore, the effective drawing width L ₁ of the heads R1 and R2 that discharge the same kind of liquid is twice the drawing width L ₀ . Similarly, the heads G1 and G2 and the heads B1 and B2 are arranged in parallel in the main scanning direction.

  The number of nozzle rows 52c provided in the droplet discharge head 50 is not limited to two, but may be one.

  Next, the control system of the droplet discharge device 10 will be described. FIG. 4 is a block diagram showing a control system of the droplet discharge device. As shown in FIG. 4, the control system of the droplet discharge apparatus 10 includes a drive unit 46 having various drivers for driving the droplet discharge head 50, the workpiece moving mechanism 20, the head moving mechanism 30, and the like, and the drive unit 46. And a control unit 40 for controlling the droplet discharge device 10.

  The driving unit 46 includes a moving driver 47 that drives and controls the linear motors of the workpiece moving mechanism 20 and the head moving mechanism 30, and a head driver 48 as a head driving unit that controls the droplet discharge head 50. Yes. In addition to this, a weight measurement driver and a maintenance driver are provided, but they are not shown.

  The control unit 40 includes a CPU 41, a ROM 42, a RAM 43, and a P-CON 44, which are connected to each other via a bus 45. The host computer 11 is connected to the P-CON 44. The ROM 42 has a control program area for storing a control program to be processed by the CPU 41, and a control data area for storing control data for performing a drawing operation, a function recovery process, and the like.

  The RAM 43 is a drawing data storage unit that stores drawing data for drawing on the workpiece W, and a position data storage unit that stores position data of the workpiece W and the droplet discharge head 50 (actually, the nozzle rows 52a and 52b). Are used as various work areas for control processing. Various drivers and the like of the drive unit 46 are connected to the P-CON 44, and the logic circuit for supplementing the function of the CPU 41 and handling interface signals with peripheral circuits is configured and incorporated. For this reason, the P-CON 44 receives various commands from the host computer 11 as they are or processes them and loads them into the bus 45, and in conjunction with the CPU 41, the data and control signals output from the CPU 41 and the like to the bus 45 are directly received. Or it processes and outputs to the drive part 46. FIG.

  Then, the CPU 41 inputs various detection signals, various commands, various data, etc. via the P-CON 44 according to the control program in the ROM 42, processes various data, etc. in the RAM 43, and then drives via the P-CON 44. The entire droplet discharge device 10 is controlled by outputting various control signals to the unit 46 and the like. For example, the CPU 41 controls the droplet discharge head 50, the workpiece moving mechanism 20, and the head moving mechanism 30 to place the head unit 9 and the workpiece W opposite to each other. Then, in synchronism with the relative movement between the head unit 9 and the workpiece W, the head is configured to eject the liquid material as droplets from the plurality of nozzles 52 of each droplet ejection head 50 mounted on the head unit 9. A control signal is sent to the driver 48. In this case, discharging the liquid material in synchronization with the movement of the workpiece W in the X-axis direction is called main scanning, and moving the head unit 9 in the Y-axis direction is called sub-scanning. The droplet discharge device 10 of this embodiment can discharge and draw a liquid material by combining main scanning and sub-scanning and repeating a plurality of times. The main scanning is not limited to the movement of the workpiece W in one direction with respect to the droplet discharge head 50 but can be performed by reciprocating the workpiece W.

  The encoder 12 is electrically connected to the head driver 48, and generates an encoder pulse with main scanning. In the main scanning, the moving table 22 is moved at a predetermined moving speed, so that encoder pulses are periodically generated.

  The host computer 11 sends control information such as a control program and control data to the droplet discharge device 10. Also, it has a function of an arrangement information generation unit that generates arrangement information as ejection control data for arranging a required amount of liquid as droplets for each film formation region on the substrate. The arrangement information includes the droplet discharge position in the film formation region (in other words, the relative position between the workpiece W and the nozzle 52), the number of droplets (in other words, the number of discharges for each nozzle 52), a plurality of main scans. Information such as ON / OFF of the nozzles 52 (in other words, a selection pattern of the plurality of nozzles 52), ejection timing, and the like is represented as a bitmap, for example. The host computer 11 can not only generate the arrangement information but also modify the arrangement information once stored in the RAM 43.

  Next, the head driver will be described with reference to FIGS. FIG. 5 is a block diagram showing the electrical configuration of the head driver, and FIG. 6 is a timing chart of drive waveforms applied to the drive means.

  As shown in FIG. 5, the head driver 48 as a head drive unit generates a CPU 71, two memories 72 and 73, a drive signal generation circuit 74 that generates a drive signal (COM), and a clock signal (CK). And a counter 76 that is connected to the encoder 12 and counts (counts) encoder pulses. Further, a shift register 81, a latch circuit 82, a level shifter 83, and a switch 84 are provided. These electrical configurations are connected via a bus 77. Thus, a drive signal (COM) can be selectively applied to the piezoelectric elements 59 corresponding to the respective nozzles 52 of the droplet discharge head 50.

  The CPU 71 generates a drive signal as digital data and stores (stores) it in the memory 72. The drive signal generation circuit 74 converts the digital data into an analog signal and generates a drive signal (COM) to be applied to the piezoelectric element 59. The memory 72 is, for example, an SRAM.

  In the present embodiment, the transmission circuit 75 generates a clock signal using a 20 MHz crystal resonator as a reference clock. The CPU 71 generates a drive signal (COM) as digital data based on the clock signal. Therefore, the drive signal (COM) can be set in increments of 0.05 μsec. Further, it is possible to control the discharge timing at which droplets are discharged every 0.05 μsec.

  The host computer 11 transmits arrangement information as ejection control data for arranging droplets as dots on the workpiece W to the head driver 48. The transmitted arrangement information is generated separately for the forward movement and the backward movement in the main scanning, and is temporarily stored (stored) in the memory 73. The memory 73 is, for example, an SDRAM.

  The arrangement information includes the relative discharge scheduled positions of the plurality of nozzles 52 with respect to the workpiece W, selection of the nozzles 52 that discharge the droplets, the number of droplet discharges, and discharge timing information when the droplets are discharged. The ejection timing information is obtained by quantifying the number of encoder pulse outputs generated by the encoder 12 in the main scan in correspondence with the planned ejection position. Then, the CPU 71 generates the nozzle data signal (SI) and the drive signal (COM) for each nozzle row as follows based on these discharge control data.

  That is, the CPU 71 decodes the discharge control data and generates nozzle data including ON / OFF information for each nozzle 52. The drive signal generation circuit 74 sets and generates a drive signal (COM) based on the nozzle data calculated by the CPU 71.

  The nozzle data signal (SI) obtained by converting the nozzle data into a serial signal is transmitted to the shift register 81 in synchronization with the clock signal (CK), and ON / OFF information for each nozzle 52 is stored. Then, in synchronization with the encoder pulse counted by the counter 76, the latch signal (LAT) generated by the CPU 71 is input to each latch circuit 82, whereby the nozzle data is latched. The latched nozzle data is amplified by the level shifter 83, and when the nozzle data is “ON”, a predetermined voltage is supplied to the switch 84. When the nozzle data is “OFF”, voltage supply to the switch 84 is not performed.

  Thus, while the voltage boosted by the level shifter 83 is supplied to the switch 84, the drive signal (COM) is applied to the piezoelectric element 59, and the droplet is ejected from the nozzle 52.

  Such discharge control is periodically performed as shown in FIG. 6 in synchronization with the relative movement (main scanning) between the head unit 9 and the workpiece W.

  As shown in FIG. 6, the drive signal COM for driving the piezoelectric element 59 is a combination of rectangular pulse signals having an amplitude with an intermediate potential interposed therebetween, and includes a plurality of drive waveforms A1 that are periodically generated. One droplet is ejected by one drive waveform A1 as follows.

  That is, the liquid material is drawn into the cavity of the pressurizing unit 57 (see FIG. 2) by increasing the potential level of the pulse signal. Next, the potential level is sharply lowered to rapidly pressurize the liquid in the cavity, and the liquid is pushed out of the nozzle 52 to form droplets (discharge). By returning the last dropped potential level to the intermediate potential, the pressure vibration (natural vibration) in the cavity is canceled.

The voltage component and time component (such as the slope of the pulse signal and the connection interval between the pulse signals) in the drive waveform A1 are parameters that are greatly related to the discharge amount and discharge stability, and require appropriate design in advance. is there.
In the present embodiment, the relative moving speed (moving speed for moving the stage 5 in the X-axis direction) between the droplet discharge head 50 and the workpiece W in the main scanning is set to 200 mm / second. The generation timing f ₁ of the LAT signal is set to 20 kHz in consideration of the natural frequency characteristics of the droplet discharge head 50 with reference to the encoder pulse output from the encoder 12 provided in the moving table 22. Therefore, if the discharge resolution is obtained by dividing the relative movement speed by the latch period, the unit of the discharge resolution is 10 μm. That is, the discharge timing can be set for each nozzle 52 in units of discharge resolution. In other words, droplets can be arranged on the surface of the workpiece W in the main scanning direction with a discharge interval of 10 μm.

  According to such a droplet discharge device 10, droplets can be discharged with respect to the workpiece W with high positional accuracy.

  As described above, the droplet discharge head 50 has the two nozzle rows 52a and 52b (collectively, the nozzle row 52c) including a plurality of nozzles 52. When the drive waveform A1 as described above is applied to the piezoelectric elements 59 and droplets are ejected from the plurality of nozzles 52, variations in the intrinsic electrical characteristics of the piezoelectric elements 59 provided for the nozzles 52, It has been found that the discharge amount of the liquid droplets discharged for each nozzle 52 varies due to differences in the design of the flow path in the head, such as a communicating cavity. In particular, electrical and mechanical crosstalk between nozzles is an important factor in variation in discharge amount.

  In the droplet discharge device 10, the application amount of the liquid material is stabilized by devising the selection pattern of the nozzles 52 that discharge droplets in consideration of such variations in the discharge amount. Specifically, a liquid material discharge method described later will be described.

<Color filter manufacturing method>
Next, the liquid material discharge method of the present embodiment will be described with reference to FIGS. 7 to 12 by taking a color filter manufacturing method as an example. FIGS. 7A and 7B are schematic plan views showing the configuration of the color filter, FIGS. 8A to 8F are schematic cross-sectional views showing the method of manufacturing the color filter, and FIGS. It is a schematic plan view which shows the Example of the discharge method.

  As shown in FIG. 7A, one or more color filters 2 are arranged on the surface of the transparent glass substrate 1 according to the size of the electro-optical device used. FIG. 2A shows an example in which six color filters 2 are arranged in a matrix in the X axis direction and the Y axis direction at a predetermined interval on one glass substrate 1. The substrate on which the color filter 2 is formed is not limited to glass. A plastic substrate made of transparent resin may be used.

  As shown in FIG. 7B, the color filter 2 has a colored layer 3 of three colors, R (red), G (green), B (blue). The colored layers 3 are each partitioned by the partition walls 4, the same colored layers 3 are arranged in the Y-axis direction (sub-scanning direction), and the different colored layers 3 are repeated in the X-axis direction (main scanning direction). Arranged. That is, the color filter 2 employs the arrangement of the stripe-type colored layer 3.

  In such a manufacturing method of the color filter 2, the droplet discharge device 10 is used to drop the liquid material of three colors including the coloring layer forming material into the film forming regions 3 r, 3 g, 3 b partitioned by the partition 4. And a film forming process for forming the colored layers 3 of three colors by drying the discharged liquid material. In the discharging process, the glass substrate 1 is placed on the stage 5 so that the stripe direction of the colored layer 3 coincides with the Y-axis direction, the droplet discharge head 50 and the glass substrate 1 are arranged to face each other, and in the X-axis direction. Main scanning for moving the stage 5 relatively is performed. A plurality of main scans are performed to discharge the three color liquid materials as droplets so that the required amount of liquid material is applied to each of the film formation regions 3r, 3g, and 3b.

  First, as shown in FIG. 8A, partition walls 4 are formed on the surface of the glass substrate 1 so as to partition the film formation regions 3r, 3g, 3b (partition wall forming step). As a forming method, a metal film such as Cr or Al or a film of a metal compound is formed on the surface of the glass substrate 1 by a vacuum deposition method or a sputtering method so as to have a light shielding property. Then, a photosensitive resin (photoresist) is applied by photolithography, and exposure, development, and etching are performed so that the film formation regions 3r, 3g, and 3b are opened, thereby forming the first partition 4a. Subsequently, a photosensitive partition wall forming material is applied to a thickness of about 2 μm by photolithography, and is exposed and developed to form a second partition wall 4b on the first partition wall 4a. The partition wall portion 4 has a so-called two-layer bank structure including a first partition wall portion 4a and a second partition wall portion 4b. In addition, the partition part 4 is not restricted to this, It is good also as a single layer structure of only the 2nd partition part 4b formed using the photosensitive partition part formation material which has light-shielding property.

  Next, in the subsequent liquid material discharge step, the surface of the glass substrate 1 is subjected to a lyophilic treatment so that the discharged liquid material lands on the film forming regions 3r, 3g, and 3b and spreads. In addition, at least the top of the second partition wall portion 4b is subjected to a liquid repellent treatment so that even if a part of the discharged liquid material lands on the second partition wall portion 4b, the liquid material is accommodated in the film forming regions 3r, 3g, 3b.

As the surface treatment method, a plasma treatment using O ₂ as a treatment gas and a plasma treatment using a fluorine-based gas as a treatment gas are performed on the glass substrate 1 on which the partition walls 4 are formed. That is, the film formation regions 3r, 3g, and 3b are subjected to lyophilic treatment, and then the surface (including the wall surface) of the second partition wall portion 4b made of a photosensitive resin is subjected to lyophobic treatment. In addition, if the material itself which forms the 2nd partition part 4b has liquid repellency, the latter process can also be skipped.

  Subsequently, the surface-treated glass substrate 1 is placed on the stage 5 of the droplet discharge device 10. 8B and 8C, the colored layer forming material is synchronized with the relative movement of the stage 5 on which the glass substrate 1 is placed and the droplet discharge head 50 in the main scanning direction. The liquid material is discharged as droplets D to the film formation regions 3r, 3g, and 3b from the plurality of nozzles 52 of the liquid droplet discharge head 50 filled with the liquid material containing liquid (liquid material discharge process). The amount of liquid applied to the film forming regions 3r, 3g, 3b is determined by the selection pattern of the nozzles 52 selected in advance for each of the film forming regions 3r, 3g, 3b and the number of droplets D discharged for each main scan. On the basis of the ejection data set to, an appropriate control signal is sent from the CPU 41 of the control unit 40 to the head driver 48 and controlled. As a result, a substantially constant amount of liquid is applied to each of the film forming regions 3r, 3g, 3b. A more detailed liquid material discharge method will be described in an embodiment described later.

Next, as shown in FIG. 8D, the solvent component is evaporated from the liquid material discharged onto the glass substrate 1 to form a colored layer 3 made of a colored layer forming material (film forming step). In the present embodiment, the three color liquid materials containing different colored layer forming materials are filled in different liquid droplet ejection heads 50 in the liquid material ejection process, and the liquid droplet ejection heads 50 are mounted on the head unit 9. A liquid material is discharged from each droplet discharge head 50 to the desired film formation regions 3r, 3g, and 3b. Then, the glass substrate 1 was set in a vacuum drying apparatus capable of drying with a constant vapor pressure of the solvent, and vacuum drying was performed to form a colored layer 3 of R, G, B, and three colors. The process of discharging and drying one color liquid may be repeated three times.
In the previous liquid discharge process, since a substantially constant amount of liquid is applied to each of the film forming regions 3r, 3g, 3b, the colored layer 3 having a substantially constant film thickness can be formed. In addition, what is necessary is just to set the film thickness of the colored layer 3 for every color, and three colors do not necessarily need to be the same. Based on the setting of the required film thickness, a required amount of liquid may be discharged to the corresponding film forming regions 3r, 3g, 3b.

  Next, as shown in FIG. 8E, the planarization layer 13 is formed so as to cover the colored layer 3 and the second partition wall 4b (a planarization layer forming step). Examples of the forming method include a method in which an acrylic resin is coated and dried by a spin coating method, a roll coating method, or the like. Further, a method in which a photosensitive acrylic resin is coated and then cured by irradiation with ultraviolet light can be employed. The film thickness is approximately 100 nm. If the surface of the glass substrate 1 on which the colored layer 3 is formed is relatively flat, the flattening layer forming step may be omitted.

  Next, as shown in FIG. 8F, a transparent electrode 14 made of ITO (Indium Tin Oxide) or the like is formed on the planarizing layer 13 (transparent electrode film forming step). Examples of the film forming method include a method of vapor deposition or sputtering in vacuum using a conductive material such as ITO as a target. The film thickness is approximately 10 nm. The formed transparent electrode 14 is appropriately processed into a necessary shape (pattern) by an electro-optical device in which the color filter 2 is used. Depending on the configuration of the electro-optical device, the transparent electrode 14 may not be required.

<Liquid material discharge method>
The liquid material ejection method of the present embodiment will be described in more detail with reference to examples. The basic concept of the liquid material ejection method of this embodiment is that a combination of selection patterns (selection methods) of the nozzles 52 that eject droplets D for each of the film formation regions 3r, 3g, and 3b is a plurality of times. In the scanning, the same film forming regions 3r, 3g, and 3b of the same color are used.

Example 1
FIGS. 9A to 9D are schematic plan views illustrating a liquid material discharge method according to the first embodiment.

  In the liquid material ejection method of the first embodiment, the combination of the selection patterns of the nozzles 52 is the same for each film formation region 3r of the same color in the four main scans. In the sub-scanning direction (Y-axis direction), the arrangement pitch of the film formation regions 3r is not an integral multiple of the substantial nozzle pitch P2 (see FIG. 2B). Accordingly, since the same number of nozzles 52 is not always applied to the film formation region 3r in the main scanning, the selection pattern of the nozzles 52 is determined according to the relative positional relationship between the plurality of nozzles 52 and the plurality of film formation regions 3r. Is changed for each main scan.

Specifically, as shown in FIG. 9A, for example, in the first main scan, the arrangement direction of the plurality of nozzles 52 in the nozzle row 52c matches the arrangement direction of the film formation region 3r of the same color. As described above, the head unit 9 of the droplet discharge device 10 and the glass substrate 1 are positioned, and the droplet D is discharged from the selected nozzle 52. Although six nozzles N ₁ to N ₆ is applied to the film forming region 3r _1, in order to reliably landed droplet D in the film forming region 3r _1, four nozzles N near the center of the film formation area 3r _{1 2 to} N ₅ are selected in succession, and 3 droplets in total in the main scanning direction (X-axis direction), ie a total of 12 droplets D, are ejected.

Similarly, in the adjacent film forming region 3r ₂ , three nozzles N _{9 to} N ₁₁ are selected in succession, and 3 droplets, a total of 9 droplets D, are discharged. Furthermore, in the film formation region 3r ₃ , four nozzles N _{15 to} N ₁₈ are selected in succession, and 3 droplets, a total of 12 droplets D, are discharged.

In the second main scanning, as shown in FIG. 9B, in the film formation region 3r ₁ , three nozzles N _{3 to} N ₅ close to the center are selected in succession, and 3 drops each, 9 drops in total. Liquid droplets D are discharged. In the film formation region 3r ₂ , four nozzles N _{9 to} N ₁₂ close to the center are selected in succession, and 3 droplets, a total of 12 droplets D, are discharged. Furthermore, in the film formation region 3r ₃ , one nozzle N ₁₇ close to the center is selected and three droplets D are discharged.

In the third main scan, as shown in FIG. 9C, in the film formation region 3r ₁ , two nozzles N ₃ and N ₄ close to the center are selected in succession, and 3 drops each, 6 drops in total. Liquid droplets D are discharged. In the film formation region 3r ₂ , one nozzle N ₁₀ close to the center is selected and three droplets D are discharged. Further, in the film formation region 3r ₃ , the two nozzles N ₁₆ and N ₁₇ close to the center are selected in succession, and 3 droplets, respectively, a total of 6 droplets D are ejected.

In the fourth main scan, as shown in FIG. 9D, in the film formation region 3r ₁ , one nozzle N ₄ close to the center is selected and three droplets D are ejected. In the film formation region 3r ₂ , two nozzles N ₁₀ and N ₁₁ close to the center are selected in succession, and 3 droplets, each of a total of 6 droplets D, are discharged. Furthermore, in the film formation region 3r ₃ , three nozzles N _{16 to} N ₁₈ close to the center are selected in succession, and 3 droplets, a total of 9 droplets D, are discharged.

By performing four main scans as described above, a total of 30 droplets D (the same ejection number) are ejected to each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ .

  In the first embodiment, when the four main scans are finished, the number of nozzles 52 selected in each film formation region 3r is a combination of the selected patterns of 1, 2, 3, and 4, respectively. D is discharged. Furthermore, the selection method of the nozzle 52 in each selection pattern is the same. Specifically, when a plurality of nozzles 52 are selected, they are selected so as to be always continuous in the sub-scanning direction (Y-axis direction) when viewed from the main scanning direction (X-axis direction). Such a combination of selection patterns is the same in the other film formation region 3r.

When the nozzle 52 is selected continuously in the sub-scanning direction and the droplet D is ejected, the ejection of the ejected droplet D is affected by the electrical and mechanical crosstalk between the nozzles as described above. The amount may vary. However, in the four main scans, the combination of the selected patterns of the nozzles 52 is the same for each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ of the same color, so that the droplets D ejected from the selected nozzles 52 As a result, a substantially constant amount of liquid material is stably applied to each film forming region 3r ₁ , 3r ₂ , 3r ₃ .
Furthermore, since at least one nozzle 52 close to the center of the film formation region 3r is selected and discharged, the droplet D lands near the center. Accordingly, the landing failure of the unnecessary droplet D landing on the adjacent film formation region 3r due to the flight of the droplet D (in other words, the landing failure where the required droplet D does not land on the desired film formation region 3r). Can be reduced.

  Such a combination of selection patterns of the nozzles 52 is naturally performed in the same manner in the other film formation regions 3g and 3b having the same color. In FIGS. 9A to 9D, the nozzle row 52c is linearly described when viewed from the main scanning direction, but in actuality, it is configured by two nozzle rows 52a and 52b (FIG. 2 ( b)). Therefore, when setting the selection pattern of the nozzles 52 in consideration of electrical and mechanical crosstalk between the nozzles, it is desirable to set the selection pattern so as to be the same for each of the nozzle rows 52a and 52b.

  In the first embodiment, in the four main scans, the plurality of nozzles 52 having the same number are always positioned relative to the plurality of film formation regions 3r. However, the present invention is not limited to this. If the combination of the selection patterns of the nozzles 52 is the same in a plurality of main scans, the relative arrangement of the plurality of nozzles 52 may be changed in at least one main scan. That is, the main scanning may be performed after the sub scanning for moving the head unit 9 in the Y-axis direction is performed. Thereby, the dispersion | variation in the discharge amount of the droplet D can be disperse | distributed.

(Example 2)
FIGS. 10A to 10D are schematic plan views illustrating a liquid material discharge method according to the second embodiment. The liquid material ejection method according to the second embodiment is obtained by partially changing the selection pattern of the nozzles 52 from the first embodiment. Specifically, as shown in FIGS. 10A and 10B, the selection pattern of the nozzles 52 in the first and second main scans is the same as that in the first embodiment. As shown in FIG. 10C, the two nozzles 52 are selected so as not to be continuous when viewed from the main scanning direction in the film formation regions 3r ₁ and 3r ₃ of the _third main scanning. Similarly, in the fourth main scanning, as shown in FIG. 10D, the two nozzles 52 are selected so as not to be continuous in the film forming region 3r ₂ when viewed from the main scanning direction.

That is, when selecting a plurality of nozzles 52 in each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ , it is not always necessary to select them continuously in the sub-scanning direction. In other words, the nozzles 52 may be discontinuously selected if the combination of the selection patterns of the nozzles 52 is the same in a plurality of main scans.

According to the liquid material discharge method of the second embodiment, the effects of the first embodiment are obtained, and the nozzles 52 are arranged in accordance with the relative arrangement of the plurality of nozzles 52 and the film formation regions 3r ₁ , 3r ₂ , 3r _3. Can increase the degree of freedom of selection. When three or more nozzles 52 can be selected in the sub-scanning direction, selection of discontinuous nozzles 52 in the sub-scanning direction may be included as long as the selection pattern is the same.

(Example 3)
FIGS. 11A to 11D are schematic plan views illustrating a liquid material discharge method according to the third embodiment. In the liquid material ejection method of the third embodiment, the selection pattern of the nozzles 52 for the film formation regions 3r ₁ , 3r ₂ , and 3r ₃ is the same as that of the first embodiment for each main scan. In addition, the number of nozzles 52 selected is reduced as the main scanning proceeds a plurality of times.

Specifically, as shown in FIG. 11A, in the first main scanning, a selection pattern for selecting four nozzles 52 in succession for each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ is used. Yes. In the second main scanning, as shown in FIG. 11B, a selection pattern for selecting three nozzles 52 in succession is used. In the third main scan, as shown in FIG. 11C, a selection pattern for selecting two nozzles 52 in succession is used. In the fourth main scan, a selection pattern for selecting one nozzle 52 is used as shown in FIG.

According to the liquid material ejection method of the third embodiment, in addition to the effects of the first embodiment, since the selection pattern of the nozzles 52 is the same for each main scan, the ejection characteristics of the selected nozzles 52 are different for each main scan. It is possible to stably reduce the variation in the discharge amount of the discharged droplets D.
Furthermore, as the number of main scans advances a plurality of times, the number of nozzles 52 selected is reduced, so the number of ejections increases rapidly, and the liquid overflows from the film formation regions 3r ₁ , 3r ₂ , 3r _3. Is preventing. That is, a substantially constant amount of liquid can be stably applied.

Example 4
12A to 12D are schematic plan views illustrating a liquid material discharge method according to the fourth embodiment. The liquid material ejection method of the fourth embodiment is different from the first embodiment in that the selection pattern of the nozzles 52 for each of the film forming regions 3r ₁ , 3r ₂ , 3r ₃ is constant over a plurality of (four times) main scans. It is said.

Specifically, as shown in FIGS. 12A to 12D, three nozzles 52 are continuously selected in the sub-scanning direction for each film forming region 3r ₁ , 3r ₂ , 3r ₃ in each main scanning. A selection pattern is used. Further, the number of droplets is adjusted in the third and fourth main scans so that the total number of droplets (the number of ejections) becomes 30 droplets (the same number) for each of the film forming regions 3r ₁ , 3r ₂ , 3r _3. Yes.

  According to the liquid material ejection method of the fourth embodiment, in addition to the effects of the first embodiment, since the selection pattern of the nozzles 52 is the same over a plurality of main scans, the ejection characteristics of the selected nozzles 52 are the same. It is stable over a plurality of main scans, and variations in the discharge amount of the discharged droplets D can be further reduced. In this case, the relative arrangement of the plurality of nozzles 52 may be changed in at least one main scan as long as the sub-scans are combined and the selection pattern of the nozzles 52 is the same.

The landing state of the droplet D in each of the film forming regions 3r ₁ , 3r ₂ , 3r ₃ shown in FIGS. 9 to 12 in the first to fourth embodiments does not necessarily indicate the arrangement thereof, but the liquid for each main scan. It indicates the number of drops (number of discharges). Therefore, in practice, by using the droplet discharge device 10 having a discharge resolution of 10 μm, it is possible to discharge droplets D intensively around the center of the film formation regions 3r ₁ , 3r ₂ , 3r _3. is there. Therefore, even if the planar size of the film forming regions 3r ₁ , 3r ₂ , 3r ₃ is reduced, the liquid material discharge method of this embodiment can be applied.
Of course, the coating amount of the liquid material is appropriately set according to the planar and three-dimensional size of the film forming regions 3r ₁ , 3r ₂ , 3r ₃ and the target value of the thickness of the colored layer 3 formed thereon. Is done.
In the first to fourth embodiments, the same number of droplets D are ejected from the selected nozzle 52 for each main scan. However, the present invention is not limited to this. For example, if the combination of the selection patterns of the nozzles 52 and the total number of ejections of the droplets D are the same when a plurality of main scans are completed, the droplets ejected in the selection pattern for selecting the plurality of nozzles 52 The number (number of discharges) may be changed in at least one selected nozzle 52. According to this, the number of droplets D ejected by a plurality of main scans can be adjusted more finely. In other words, the coating amount of the liquid material applied to each of the film formation regions 3r ₁ , 3r ₂ , 3r ₃ can be adjusted so as to approach the target value.

(Embodiment 2)
<Other liquid discharge methods>
Next, another liquid discharge method will be described with reference to FIG. FIG. 13 is a timing chart of drive waveforms applied to the drive means of the second embodiment.

The drive waveform generated during one period of the LAT signal is not limited to one. For example, as shown in FIG. 13, in one period f ₂ of the LAT signal, to generate two drive waveforms A1, A2. And it is good also as a structure of the control signal which selects either of two drive waveform A1, A2 with a LAT signal and CH signal. According to this, compared with the configuration of the LAT signal and the drive waveform A1 shown in FIG. 6, the generation cycle of each of the drive waveforms A1 and A2 is set to be short, and high frequency driving is possible. In this way, a required amount of liquid can be applied to the corresponding film formation region in a shorter time.

Further, for example, in FIG. 9A showing the liquid material discharge method of Example 1 of Embodiment 1, the nozzles N _{2 to} N ₅ and the nozzle N are provided in the film formation regions 3r ₁ , 3r ₂ , 3r _{3. 9} to N ₁₁ and the nozzle N ₁₅ to N ₁₈ is selected and the droplet D is discharged.

In another liquid material ejection method of the present embodiment, the selected nozzles N _{2 to} N ₅ and the nozzles N _{9 to} N ₁₁ are selected according to a waveform selection pattern for sequentially selecting the drive waveforms A1 and A2 that are generated periodically. and those that apply to the nozzles N ₁₅ to N _18.

Specifically, the nozzle _{N 2, N 4, N 9} , N 11, N 16, the driving waveforms A1 is applied to the piezoelectric element 59 corresponding to N _18, the nozzle _{N 3, N 5, N 10} , N 15, applying a driving waveform A2 to the piezoelectric element 59 corresponding to N _17. In this way, the same drive waveform is not applied to the adjacent nozzles 52 among the plurality of selected nozzles 52. That is, a waveform selection pattern that sequentially selects two drive waveforms A1 and A2 for a plurality of selected nozzles 52 arranged in the sub-scanning direction is employed. The order of waveform selection may be the order of drive waveform A2 and drive waveform A1. In addition, the number of drive waveforms generated in one cycle defined by the LAT signal is not limited to this, and may be three or more. Even in that case, a waveform selection pattern for sequentially selecting a plurality of drive waveforms is applied.

  According to the other liquid material ejection method, one of the plurality of periodically generated drive waveforms A1 and A2 is selected and applied to the piezoelectric element 59 of the selected nozzle 52. The droplets D are not simultaneously ejected from the plurality of nozzles 52 formed. Therefore, it is possible to reduce variations in the discharge amount of the droplets D caused by at least electrical crosstalk between the selected nozzles.

Furthermore, since a waveform selection pattern for sequentially selecting a plurality of drive waveforms A1 and A2 is applied to the selection pattern of the nozzle 52, the selection of the two drive waveforms A1 and A2 is uniform in the main scan. Therefore, the dullness of the drive waveforms A1 and A2 that occurs when the drive waveforms A1 and A2 are selected in a biased manner is reduced. That is, the variation in the discharge amount of the droplet D due to the dullness of the drive waveforms A1 and A2 is reduced, and the variation in the coating amount is suppressed for each of the film forming regions 3r ₁ , 3r ₂ , 3r ₃ , and a substantially constant amount of liquid material Can be stably applied.

  It goes without saying that such other liquid material discharge methods are also applied to the case where main scanning is performed on other film formation regions 3g and 3b of the same color. Moreover, it can apply to all of Examples 1-4 of the said Embodiment 1. FIG. The plurality of drive waveforms A1 and A2 that are periodically generated may not be the same drive waveform. By changing the maximum potential (in other words, drive voltage) in the drive waveforms A1 and A2, the discharge amount of the discharged droplet D can be changed, and the application amount of the liquid material applied to the film formation region is further finely adjusted. It becomes possible to do.

(Embodiment 3)
Next, a method for manufacturing an organic EL (Electro Luminescence) element to which the liquid material discharge method of the first embodiment or another liquid material discharge method of the second embodiment is applied will be described with reference to FIGS. explain. FIG. 14 is a schematic sectional view showing an organic EL device, and FIGS. 15A to 15F are schematic sectional views showing a method for producing an organic EL element.

<Organic EL device>
As shown in FIG. 14, the organic EL device 600 of this embodiment includes an element substrate 601 having a light emitting element portion 603 as an organic EL element, and a sealing substrate 620 sealed with a space 622 from the element substrate 601. And. The element substrate 601 includes a circuit element portion 602 on the element substrate 601, and the light emitting element portion 603 is formed so as to overlap the circuit element portion 602 and is driven by the circuit element portion 602. In the light-emitting element portion 603, three-color light-emitting layers 617R, 617G, and 617B made of an organic light-emitting material are formed in the light-emitting layer forming region A as each film forming region, and are in a stripe shape. The element substrate 601 includes three light emitting layer forming regions A corresponding to the three color light emitting layers 617R, 617G, and 617B as a set of picture elements, and the picture elements are arranged in a matrix on the circuit element portion 602 of the element substrate 601. It is arranged. The organic EL device 600 emits light from the light emitting element portion 603 to the element substrate 601 side.

  The sealing substrate 620 is made of glass or metal, and is bonded to the element substrate 601 via a sealing resin. A getter agent 621 is attached to the sealed inner surface. The getter agent 621 absorbs water or oxygen that has entered the space 622 between the element substrate 601 and the sealing substrate 620 and prevents the light emitting element portion 603 from being deteriorated by the water or oxygen that has entered. The getter agent 621 may be omitted.

  The element substrate 601 has a plurality of light emitting layer forming regions A on the circuit element unit 602, and is formed in the banks 618 partitioning the plurality of light emitting layer forming regions A and the plurality of light emitting layer forming regions A. An electrode 613 and a hole injection / transport layer 617a stacked on the electrode 613 are provided. In addition, a light emitting element portion 603 having light emitting layers 617R, 617G, and 617B formed by applying three kinds of liquid materials including a light emitting layer forming material in a plurality of light emitting layer forming regions A is provided. The bank 618 is formed using an insulating material and covers the periphery of the electrode 613 so that the light emitting layers 617R, 617G, and 617B stacked on the hole injection / transport layer 617a and the electrode 613 are not electrically short-circuited. ing.

  The element substrate 601 is made of a transparent substrate such as glass, for example. A base protective film 606 made of a silicon oxide film is formed on the element substrate 601, and an island-like semiconductor film made of polycrystalline silicon is formed on the base protective film 606. 607 is formed. Note that a source region 607a and a drain region 607b are formed in the semiconductor film 607 by high concentration P ion implantation. A portion where P ions are not introduced is a channel region 607c. Further, a transparent gate insulating film 608 covering the base protective film 606 and the semiconductor film 607 is formed, and a gate electrode 609 made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 608, and the gate electrode 609 is formed. A transparent first interlayer insulating film 611a and a second interlayer insulating film 611b are formed on the gate insulating film 608. The gate electrode 609 is provided at a position corresponding to the channel region 607 c of the semiconductor film 607. Further, contact holes 612a and 612b are formed through the first interlayer insulating film 611a and the second interlayer insulating film 611b and connected to the source region 607a and the drain region 607b of the semiconductor film 607, respectively. A transparent electrode 613 made of ITO (Indium Tin Oxide) or the like is patterned and arranged in a predetermined shape on the second interlayer insulating film 611b, and one contact hole 612a is connected to the electrode 613. The other contact hole 612 b is connected to the power supply line 614. In this manner, the driving thin film transistor 615 connected to each electrode 613 is formed in the circuit element portion 602. Note that although a storage capacitor and a switching thin film transistor are also formed in the circuit element portion 602, these are not shown in FIG.

  The light-emitting element portion 603 includes an electrode 613 serving as an anode, a hole injection / transport layer 617a sequentially stacked on the electrode 613, light-emitting layers 617R, 617G, and 617B (collectively, light-emitting layer Lu), a bank 618, A cathode 604 is provided so as to cover the light emitting layer Lu. The hole injection / transport layer 617a and the light emitting layer Lu constitute a functional layer 617 in which light emission is excited. Note that if the cathode 604, the sealing substrate 620, and the getter agent 621 are formed of a transparent material, light emitted from the sealing substrate 620 side can be emitted.

  The organic EL device 600 has a scanning line (not shown) connected to the gate electrode 609 and a signal line (not shown) connected to the source region 607a, and a switching thin film transistor by a scanning signal transmitted to the scanning line. When (not shown) is turned on, the potential of the signal line at that time is held in the storage capacitor, and the on / off state of the driving thin film transistor 615 is determined according to the state of the storage capacitor. Then, current flows from the power supply line 614 to the electrode 613 through the channel region 607c of the driving thin film transistor 615, and further current flows to the cathode 604 through the hole injection / transport layer 617a and the light emitting layer Lu. The light emitting layer Lu emits light according to the amount of current flowing through it. The organic EL device 600 can display desired characters, images, and the like by such a light emission mechanism of the light emitting element portion 603. Further, in the organic EL device 600, since the light emitting layer Lu is formed by using the liquid material ejection method of the first embodiment or another liquid material ejection method of the second embodiment, a substantially constant amount of liquid material is formed. Is applied to each light emitting layer forming region A, and has high display quality with few display defects such as light emission unevenness and luminance unevenness and enables high-definition display.

<Method for producing organic EL element>
Next, the manufacturing method of the light emitting element part 603 as an organic EL element of this embodiment is demonstrated with reference to FIG. 15A to 15F, the circuit element portion 602 formed on the element substrate 601 is not shown.

  In the manufacturing method of the light emitting element portion 603 of this embodiment, the step of forming the electrode 613 at a position corresponding to the plurality of light emitting layer forming regions A of the element substrate 601 and the bank 618 are formed so as to partially cover the electrode 613. And a bank forming process. Further, the surface treatment of the light emitting layer forming region A partitioned by the bank 618, and the surface treatment of the light emitting layer forming region A with a liquid containing a hole injecting / transporting layer forming material are performed. A step of discharging and drawing the transport layer 617a and a step of forming a hole injection / transport layer 617a by drying the discharged liquid material are provided. Further, a discharge step of discharging three types of liquid materials including the light emitting layer forming material into the light emitting layer forming region A, and a film forming step of forming the light emitting layer Lu by drying the three types of discharged liquid materials. I have. Further, a step of forming a cathode 604 so as to cover the bank 618 and the light emitting layer Lu is provided. The application of each liquid material to the light emitting layer formation region A is performed using the liquid material discharge method of the first embodiment or another liquid material discharge method of the second embodiment. Therefore, the arrangement of the droplet discharge heads 50 in the head unit 9 shown in FIG. 3 is applied.

  In the electrode (anode) forming step, an electrode 613 is formed at a position corresponding to the light emitting layer forming region A of the element substrate 601 as shown in FIG. As a forming method, for example, a transparent electrode film is formed on the surface of the element substrate 601 by a sputtering method or a vapor deposition method in vacuum using a transparent electrode material such as ITO. Thereafter, a method of forming the electrode 613 by etching while leaving only a necessary portion by a photolithography method can be given. Then, the process proceeds to the bank formation process.

  In the bank forming step, as shown in FIG. 15B, a bank 618 is formed so as to cover the periphery of the plurality of electrodes 613 of the element substrate 601. As a material of the bank 618, it is desirable that the material has durability against a solvent of three kinds of liquids 100R, 100G, and 100B including a light emitting layer forming material, which will be described later. An organic material having an insulating property such as an acrylic resin, an epoxy resin, a photosensitive polyimide, or the like is preferable. As a method for forming the bank 618, for example, the photosensitive organic material is applied to the surface of the element substrate 601 on which the electrode 613 is formed by a roll coating method or a spin coating method, and dried to have a thickness of about 2 to 3 μm. A photosensitive resin layer is formed. Then, a method of forming the bank 618 by exposing and developing a mask having an opening corresponding to the size of the light emitting layer formation region A and facing the element substrate 601 at a predetermined position can be mentioned. And it progresses to a surface treatment process.

In the step of surface-treating the light emitting layer forming region A, the surface of the element substrate 601 on which the bank 618 is formed is first plasma-treated using O ₂ gas as a processing gas. As a result, the surface of the electrode 613 and the surface of the bank 618 (including the wall surface) are activated to perform lyophilic treatment. Next, plasma processing is performed using a fluorine-based gas such as CF ₄ as a processing gas. As a result, the fluorine-based gas reacts only on the surface of the bank 618 made of a photosensitive resin, which is an organic material, and the liquid repellent treatment is performed. Then, the process proceeds to the hole injection / transport layer forming step.

  In the hole injection / transport layer forming step, a liquid 90 containing a hole injection / transport layer forming material is applied to the light emitting layer forming region A as shown in FIG. As a method for applying the liquid 90, the droplet discharge device 10 including the head unit 9 of FIG. 3 and the liquid discharge method of the first embodiment or another liquid discharge method of the second embodiment are used. . The liquid 90 discharged from the droplet discharge head 50 lands on the electrode 613 of the element substrate 601 as the droplet D and spreads wet. A substantially constant amount of the liquid 90 is ejected as droplets D in accordance with the area of the light emitting layer formation region A. Then, the process proceeds to the drying / film formation process.

  In the drying / film formation process, the element substrate 601 is heated by a method such as lamp annealing to dry and remove the solvent component of the liquid 90 and inject holes into a region partitioned by the bank 618 of the electrode 613. / Transport layer 617a is formed. In this embodiment, 3,4-polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) was used as the hole injection / transport layer forming material. In this embodiment, the hole injection / transport layer 617a made of the same material is formed in each light emitting layer forming region A. However, the material of the hole injection / transport layer 617a corresponding to the light emitting layer Lu formed later. May be changed for each light emitting layer forming region A. Then, the process proceeds to the next liquid discharge process.

  In the liquid discharge step, as shown in FIG. 15D, three types of light emitting layer forming materials containing a plurality of light emitting layer forming regions A from a plurality of droplet discharging heads 50 using a droplet discharging device 10 are used. Liquids 100R, 100G, and 100B are applied. The liquid body 100R includes a material for forming the light emitting layer 617R (red), the liquid body 100G includes a material for forming the light emitting layer 617G (green), and the liquid body 100B includes a material for forming the light emitting layer 617B (blue). It is out. Each of the landed liquids 100R, 100G, and 100B wets and spreads in the light emitting layer forming region A and the cross-sectional shape rises in an arc shape. As a method for applying these liquids 100R, 100G, and 100B, the liquid discharge method of the first embodiment or another liquid discharge method of the second embodiment was used. The drive waveform (voltage pulse) is preferably set for each of the liquid materials 100R, 100G, and 100B. That is, the drive waveform is set for each droplet discharge head 50 filled with the liquids 100R, 100G, and 100B. Then, the process proceeds to the drying / film formation process.

  In the drying / film formation step, as shown in FIG. 15E, the solvent components of the discharged liquid materials 100R, 100G, and 100B are dried and removed, and hole injection / transport in each light emitting layer forming region A is performed. The light emitting layers 617R, 617G, and 617B are deposited on the layer 617a. As a drying method of the element substrate 601 on which each of the liquid materials 100R, 100G, and 100B is discharged, it is preferable to dry under reduced pressure so that the evaporation rate of the solvent can be made substantially constant. And it progresses to a cathode formation process.

In the cathode forming step, as shown in FIG. 15F, the cathode 604 is formed so as to cover the light emitting layers 617R, 617G, and 617B of the element substrate 601 and the surface of the bank 618. As a material of the cathode 604, it is preferable to use a combination of metals such as Ca, Ba, and Al and fluorides such as LiF. In particular, it is preferable to form a film of Ca, Ba, or LiF having a small work function on the side close to the light emitting layers 617R, 617G, and 617B and a film of Al or the like having a large work function on the far side. Further, a protective layer such as SiO ₂ or SiN may be laminated on the cathode 604. In this way, oxidation of the cathode 604 can be prevented. Examples of the method for forming the cathode 604 include vapor deposition, sputtering, and CVD. In particular, the vapor deposition method is preferable in that the light emitting layers 617R, 617G, and 617B can be prevented from being damaged by heat.

  The element substrate 601 thus completed is provided with a substantially constant amount of each of the liquid materials 100R, 100G, and 100B as droplets D on the light emitting layer formation region A, and the film thickness after drying and film formation is different from each other. In the light emitting layer forming region A, the light emitting layers 617R, 617G, and 617B that are substantially constant are provided.

  According to the method for manufacturing the light emitting element portion 603 of the third embodiment, in the discharge process of the liquid materials 100R, 100G, and 100B, the discharge method of the liquid material of the first embodiment or the discharge of another liquid material of the second embodiment. A substantially constant amount of each of the liquid materials 100R, 100G, and 100B is stably applied to the light emitting layer forming region A disposed on the element substrate 601 using the method. The respective light emitting layers 617R, 617G, and 617B in which the film thickness after drying and film formation is substantially constant in each light emitting layer forming region A are obtained.

  Further, when the organic EL device 600 is manufactured using the method for manufacturing the light emitting element portion 603 of the third embodiment, the thickness of each of the light emitting layers 617R, 617G, and 617B is substantially constant. The resistance for each of 617G and 617B is substantially constant. Therefore, when the circuit element unit 602 applies a driving voltage to the light emitting element unit 603 to emit light, unevenness in light emission and luminance due to resistance unevenness in each of the light emitting layers 617R, 617G, and 617B are reduced. That is, it is possible to manufacture the organic EL device 600 having a display quality with a high definition and a good appearance with little light emission unevenness and brightness unevenness.

  Various modifications other than the above embodiment are conceivable. Hereinafter, a modification will be described.

  (Modification 1) In Examples 1 to 4 of the liquid material ejection method of the first embodiment, the drive waveform A1 applied to the nozzle 52 applied to the film formation regions 3r, 3g, 3b is different types (different colors) to be ejected. It may be different for each liquid. According to this, the droplet D can be discharged with the target discharge amount for every liquid.

  (Modification 2) In the manufacturing method of the color filter 2 of the first embodiment, the arrangement of the colored layers 3 of R, G, B, and three colors is not limited to the stripe method. Even in the case of a mosaic method in which the colored layers 3 of the same color are arranged in an oblique direction or a delta method in which the colored layers 3 of the respective colors are arranged at positions corresponding to the apexes of the triangle, the liquid material discharge method of the first embodiment is applied. Can do. The colored layer 3 is not limited to three colors, and may be multicolored with colors other than R, G, and B added.

(Modification 3) In another liquid material ejection method of the second embodiment, the method of applying the plurality of drive waveforms A1 and A2 to the selection pattern of the nozzles 52 (the selected nozzles 52) is limited to this. Not. For example, three drive waveforms A1, A2, and A3 are generated periodically. In the first main scan shown in FIG. 9A, for the plurality of nozzles 52 selected in the film formation regions 3r ₁ , 3r ₂ and 3r ₃ , the drive waveform A1 and the nozzle N ₃ are applied to the nozzle N _2. drive waveform A2, the driving waveform A3 the nozzle N _4, the drive waveform A2 the nozzle N _5, the driving waveform A1 in the nozzle N _9, the driving waveform A3 the nozzle N _10, the nozzle N ₁₁ driving waveforms A1 , the driving waveform A3 the nozzle N _15, the nozzle N ₁₆ may be applied so that the driving waveforms A2. That is, it is desirable not to apply the same drive waveform to the adjacent nozzles 52 among the plurality of selected nozzles 52, and to apply the drive waveforms A1, A2, and A3 so as to be substantially equal. According to this, at least electrical crosstalk between the nozzles can be suppressed, and variations in the discharge amount of the droplets D due to the dullness of the drive waveform can be reduced.

  (Modification 4) The manufacturing method of the light emitting element portion 603 of the third embodiment is not limited to forming the light emitting layer Lu of three colors. For example, a monochromatic configuration such as white or red may be used. According to this, an illuminating device or a photosensitive device provided with a monochromatic organic EL element can be provided.

  (Modification 5) In the liquid discharge method of the first embodiment and the other liquid discharge method of the second embodiment, the relative relationship between the plurality of nozzles 52 and the film formation regions 3r, 3g, 3b in the main scan. The positional relationship is not limited to this. For example, the rotation mechanism 7 is driven in the droplet discharge device 10, and the head unit 9 is moved to the workpiece W (glass substrate) so that the arrangement direction of the plurality of nozzles 52 and the arrangement direction of the film formation regions 3r, 3g, 3b intersect. Position with respect to 1). According to this, the number of nozzles 52 applied to the film forming regions 3r, 3g, 3b in the main scanning can be increased, and the droplets D can be landed at a higher density.

  (Modification 6) The device manufacturing method to which the liquid material discharging method of the first embodiment or the other liquid material discharging method of the second embodiment can be applied is the method for manufacturing the color filter 2 or the organic EL element. The method is not limited. As described above, the present invention can also be applied to formation of a hole injection / transport layer. Further, for example, a method of manufacturing a metal wiring that forms a wiring having a predetermined pattern by discharging a liquid material containing a conductive material to a film forming region on the substrate, and a retardation film forming material in the film forming region on the substrate. The present invention can also be applied to a method of forming a retardation film that constitutes a display pixel by discharging a liquid material containing the liquid material.

The schematic perspective view which shows the structure of a droplet discharge apparatus. (A) is a perspective view which shows a droplet discharge head, (b) is a top view which shows the arrangement | positioning state of a nozzle. FIG. 3 is a schematic plan view showing the arrangement of droplet discharge heads in the head unit. The block diagram which shows the control system of a droplet discharge apparatus. FIG. 3 is a block diagram showing an electrical configuration of a head driver. 4 is a timing chart of driving waveforms applied to the driving unit of the first embodiment. (A) And (b) is a schematic plan view which shows the structure of a color filter. (A)-(f) is a schematic sectional drawing which shows the manufacturing method of a color filter. FIG. 3 is a schematic plan view illustrating a liquid discharge method according to the first embodiment. FIG. 6 is a schematic plan view illustrating a liquid discharge method according to the second embodiment. FIG. 6 is a schematic plan view illustrating a liquid discharge method according to a third embodiment. FIG. 6 is a schematic plan view illustrating a liquid discharge method according to a fourth embodiment. 10 is a timing chart of driving waveforms applied to the driving unit of the second embodiment. 1 is a schematic cross-sectional view showing the structure of an organic EL device. (A)-(f) is a schematic sectional drawing which shows the manufacturing method of an organic EL element.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Glass substrate as a board | substrate, 2 ... Color filter, 3 ... Colored layer, 3r, 3g, 3b ... Film formation area, 52 ... Nozzle, 59 ... Piezoelectric element as a drive means, 100R, 100G, 100B ... Light emitting layer formation Liquid material containing material, 603... Light emitting element portion as organic EL element, 617... Functional layer, 617 R, 617 G, 617 B... Light emitting layer, A. D: Droplet.

Claims (9)

Discharge of a liquid material having a discharge step of performing a plurality of scans for relatively moving a plurality of nozzles and a substrate and discharging a liquid material as droplets from the plurality of nozzles to a plurality of film forming regions arranged on the substrate A method,
In the discharging step, the combination of nozzle selection patterns for discharging the droplets in the plurality of scans is the same for each film forming region.   2. The liquid discharge method according to claim 1, wherein the nozzle selection pattern for each film formation region is different for each of the scans in the discharge step.   2. The liquid discharge method according to claim 1, wherein in the discharge step, a selection pattern of the nozzles for each of the film forming regions is constant for each scanning.   2. The liquid discharge method according to claim 1, wherein in the discharge step, a selection pattern of the nozzles for each of the film formation regions is constant over the plurality of scans.   5. The liquid droplet is ejected by applying one of a plurality of periodically generated drive waveforms to the selected nozzle drive means in the discharge step. 6. The discharge method of the liquid as described in any one of Claims.   In the scanning, in the scanning, among the plurality of nozzles selected by the nozzle selection pattern, the same driving waveform is not applied to the driving means of adjacent nozzles, and the selection is performed for each of the plurality of driving waveforms. 6. The method for discharging a liquid material according to claim 5, wherein:   7. The discharge process according to claim 1, wherein at least one nozzle close to a center of the film formation region is used among nozzles applied to the film formation region in the scanning. 8. Liquid material discharge method. A method for producing a color filter having a plurality of colored layers in a plurality of film forming regions on a substrate,
A discharge step of discharging a plurality of color liquid materials including a coloring layer forming material to the plurality of film forming regions using the liquid material discharge method according to claim 1,
And a film forming step of solidifying the discharged liquid material to form the colored layers of the plurality of colors. A method for producing an organic EL element having a functional layer including a light emitting layer in a plurality of film formation regions on a substrate,
A discharge step of discharging a liquid containing a light emitting layer forming material to the plurality of film formation regions using the liquid discharge method according to claim 1,
And a film forming step of solidifying the discharged liquid material to form the light emitting layer. A method for manufacturing an organic EL element, comprising:

Images