JP2009135012A - Coating apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve uniformity of a drying speed in a liquid material discharged from a plurality of outlet ports. <P>SOLUTION: Each of two bellows expanding members 31 is mounted at both sides in the main scanning direction of a coating head 14. Further in the coating head 14, a plurality of outlet ports 171 are arranged at equal pitches in a sub-scanning direction normal to the main scanning direction to discharge an organic EL liquid onto a substrate 9. In an coating apparatus 1, the expanding member 31 expands at a rear space in the forward direction of the coating head 14 to feed air into the space, by moving the coating head 14 in the main scanning direction by means of a head-transferring mechanism 15; and an air flow is generated to agitate an atmosphere around the organic EL liquid directly after it is discharged onto the substrate 9. Consequently, the concentration of a solvent component in the organic EL liquid is uniformized at the atmosphere around the organic EL liquid discharged from a plurality of outlet ports 171, to improve uniformity of the drying speed in the organic EL liquid. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a coating apparatus that applies a flowable material to a substrate.

  Conventionally, as an apparatus for applying a fluid material such as a resist solution on a semiconductor substrate, a nozzle that continuously ejects the fluid material is scanned on the substrate as disclosed in Patent Documents 1 and 2. Thus, there is known a coating apparatus that applies a fluid material on a substrate in a plurality of parallel lines, and applies the fluid material to the entire main surface of the substrate by spreading and contacting each other.

  In such a coating apparatus, various techniques for improving the uniformity of the film thickness of the flowable material have been proposed. For example, in Patent Document 1, a semiconductor substrate coated with a coating liquid by a resist coating apparatus is exposed to a solvent atmosphere of the coating liquid in a solvent atmosphere apparatus provided separately from the resist coating apparatus, thereby removing the solvent from the surface of the coating liquid. A technique for reducing the viscosity of the surface of the coating liquid by adhering to the surface of the coating liquid, and then forming an air flow in a container in which the substrate is accommodated and flattening the surface of the coating liquid by the air flow is disclosed. In the coating film forming apparatus of Patent Document 2, a drying prevention plate that covers almost the entire substrate is provided at a position within 2 mm above the substrate, and a coating liquid for an insulating film is formed in a linear gap formed on the drying prevention plate. By scanning a nozzle that discharges the substrate with respect to the substrate, the coating liquid is uniformly applied onto the substrate. Thereby, a high concentration solvent atmosphere is formed between the substrate and the drying prevention plate, and drying of the coating solution applied to the substrate is suppressed.

  By the way, an application apparatus that applies a fluid material to a substrate by scanning a nozzle that discharges the fluid material applies a fluid material containing a pixel forming material to a glass substrate for a flat display device. Applications are also being studied. In a typical example, the fluid material is applied in stripes at a predetermined pitch by repeatedly scanning a nozzle along a partition formed on a substrate. At this time, on the substrate, the solvent component evaporates from each line (linear element) of the flowable material and is dried in the order in which these lines are applied. In the fluid material, the pixel forming material is sufficiently dispersed until it dries and is fixed almost uniformly on the substrate. However, if the time from application to the end of drying is short, the degree of dispersion of the pixel forming material varies. Thus, the drying of the flowable material ends in a state different from the above region.

Since the amount of the solvent component that evaporates from the surrounding fluid material is smaller in the line on the start end side and the line on the end side of the application on the substrate than in the central part of the application region, the concentration of the solvent component in the atmosphere is less Lower. For this reason, the drying time of the fluid material is shorter than in other regions, and the dispersion state of the pixel forming material is different from the central portion. Therefore, in Patent Document 3, the flowable material is applied to the non-application area outside the application area (forms a dummy line) on each of the application start and end sides on the substrate. A method for suppressing the drying time of the ink from becoming shorter than other regions is disclosed.
JP 2003-17402 A Japanese Patent Laid-Open No. 2005-13787 JP 2007-144240 A

  On the other hand, in order to improve the tact time in the coating apparatus, the flowable material is striped on the glass substrate by repeating scanning of a plurality of nozzles and step movement of the substrate in a direction perpendicular to the scanning direction. Since the fluid material is not applied to the rear side of the substrate in the step movement direction, the fluid material applied by the nozzle located at the rearmost side in the step movement direction among the plurality of nozzles. In the vicinity of the line, the concentration of the solvent component in the atmosphere is lower than that around the line of the flowable material applied by other nozzles. For this reason, the flowable material line applied by the rearmost nozzle dries faster than the flowable material lines applied by the other nozzles, and the dispersion state of the pixel forming material differs from the other lines. End up. As a result, when the substrate is viewed as a whole, coating unevenness occurs, and the display quality in the flat display device after becoming a product may deteriorate.

  The present invention has been made in view of the above problems, and an object of the present invention is to improve the uniformity of the drying rate of the flowable material discharged from a plurality of discharge ports.

  The invention according to claim 1 is a coating apparatus for applying a flowable material to a substrate, comprising: a substrate holding portion for holding the substrate; a flowable material including a volatile solvent and a material applied on the substrate. A discharge mechanism that discharges toward the substrate from a plurality of discharge ports arranged at equal intervals in the sub-scan direction parallel to the substrate, and the main scan direction perpendicular to the sub-scan direction and parallel to the substrate. A main scanning mechanism that moves the ejection mechanism; a sub-scanning mechanism that moves the substrate relative to the ejection mechanism in the sub-scanning direction each time the ejection mechanism moves in the main scanning direction; and An airflow generation unit that is attached to the discharge mechanism and generates an airflow around the flowable material immediately after being discharged onto the substrate by the movement of the discharge mechanism in the main scanning direction by the main scanning mechanism. With.

  Invention of Claim 2 is a coating device of Claim 1, Comprising: The said air flow generation | occurrence | production part advances the said discharge mechanism by the movement to the said main scanning direction of the said discharge mechanism by the said main scanning mechanism. Air is fed into the space behind the direction.

  A third aspect of the present invention is the coating apparatus according to the second aspect, wherein the air flow generation unit is arranged on the rear side in the traveling direction of the discharge mechanism by the movement of the discharge mechanism in the main scanning direction. It is a bellows-like member that extends in the space and sends ambient air into the space.

  Invention of Claim 4 is a coating device of Claim 1, Comprising: The said air flow generation | occurrence | production part moves together with the said discharge mechanism with the said discharge mechanism by the said main scanning mechanism, and the said discharge mechanism. It is a ventilation member which sends air between the said board | substrates.

  A fifth aspect of the present invention is the coating apparatus according to the fourth aspect, wherein the blowing member is attached to the sub-scanning direction side of the ejection mechanism.

  A sixth aspect of the present invention is the coating apparatus according to the fifth aspect, wherein the blower member is attached to the front side in the intermittent relative movement direction of the substrate by the sub-scanning mechanism.

  A seventh aspect of the present invention is the coating apparatus according to the fourth aspect, wherein the blower member is attached to the main scanning direction side of the discharge mechanism.

  An eighth aspect of the present invention is the coating apparatus according to any one of the first to seventh aspects, wherein the discharge mechanism moves on the substrate in the forward and backward paths of movement in the main scanning direction. The material is discharged, and the air flow generation unit generates the air flow in both the forward path and the return path of the movement of the discharge mechanism.

  A ninth aspect of the present invention is the coating apparatus according to any one of the first to eighth aspects, wherein the fluid material includes an organic EL material or a hole transport material for an organic EL display device.

  According to the present invention, by generating an air flow around the flowable material immediately after being discharged onto the substrate, the solvent component of the flowable material in the atmosphere around the flowable material discharged from the plurality of discharge ports. The concentration can be made uniform, and as a result, the uniformity of the drying speed of the flowable material can be improved.

  In the second aspect of the invention, the concentration of the solvent component is made uniform without affecting the discharge of the fluid material from the discharge mechanism by sending air into the space on the rear side in the traveling direction of the discharge mechanism. In the invention of claim 3, air can be easily fed into the space on the rear side in the traveling direction of the discharge mechanism.

  In the invention of claim 4, the concentration of the solvent component can be made uniform with a simple structure, and in the invention of claim 6, the concentration of the solvent component can be made more uniform.

  In the invention of claim 8, the fluid material can be applied over a wide area on the substrate in a short time, and in the invention of claim 9, the deterioration of display quality due to uneven application in the organic EL display device is suppressed. can do.

  FIG. 1 is a plan view showing a coating apparatus 1 according to the first embodiment of the present invention, and FIG. 2 is a front view of the coating apparatus 1. The coating apparatus 1 is an apparatus that applies a flowable material including a pixel forming material for a flat display device to a glass substrate 9 for flat display devices (hereinafter simply referred to as “substrate 9”). In the present embodiment, in the coating apparatus 1, a substrate 9 for an organic EL (Electro Luminescence) display device of an active matrix driving system is applied onto the substrate 9 as a volatile solvent and a light emitting material of one color. A fluid material containing an organic EL material (hereinafter referred to as “organic EL liquid”) is applied.

  As shown in FIG. 2, the coating apparatus 1 includes a substrate holding portion 11 that holds the substrate 9 in contact with one main surface (the main surface on the (−Z) side in FIG. 2) of the substrate 9. As shown in FIGS. 1 and 2, the substrate holding portion 11 is horizontally moved in a predetermined direction parallel to the main surface of the substrate 9 (that is, the Y direction in FIG. 1 and hereinafter referred to as “sub-scanning direction”). And a substrate moving mechanism 12 that rotates about an axis oriented in the vertical direction (that is, the Z direction). The substrate holding unit 11 includes a heater (not shown) that is a substrate heating unit that heats the substrate 9 from below. In the coating region 91 (indicated by a thin line rectangle in FIG. 1) on the (+ Z) side main surface 90 of the substrate 9, a plurality of partition walls each extending in the X direction in FIG. 1 are constant in the Y direction. Are arranged at a pitch (for example, a pitch of 100 to 150 micrometers (μm)). The substrate holding portion holds the substrate 9 by holding the end portion in the Y direction of the substrate 9 in addition to the one that holds the substrate 9 in contact with the main surface of the substrate 9 on the (−Z) side. Etc.

  The coating apparatus 1 also has a coating head 14 that is a discharge mechanism that discharges a flowable material toward the main surface 90 of the substrate 9 held by the substrate holding unit 11, and the coating head 14 is parallel to the main surface 90 of the substrate 9. In addition, the head moving mechanism 15 that moves horizontally in the direction perpendicular to the sub-scanning direction (that is, the X direction in FIG. 1 and hereinafter referred to as “main scanning direction”) and the movement direction of the coating head 14 (that is, the X direction). ), Two liquid receiving parts 16 (see FIG. 2) for receiving the organic EL liquid from the coating head 14 and a fluid material supplying part 18 for supplying a fluid material to the coating head 14. And a control unit 2 for controlling these components.

  In the coating apparatus 1, the head moving mechanism 15 is a main scanning mechanism that moves the coating head 14 in the main scanning direction (that is, main scanning), and the substrate moving mechanism 12 moves the coating head 14 in the main scanning direction. The sub-scanning mechanism moves the substrate 9 in the sub-scanning direction (ie, sub-scans) each time it is completed. During main scanning of the coating head 14, acceleration or deceleration is completed in the vicinity of the liquid receiving unit 16, and the coating head 14 is at a substantially constant speed (for example, 3 to 5 meters (m) per second) above the substrate 9. Move at. The width of the substrate 9 in the main scanning direction is, for example, 1 to 2 m.

  As shown in FIGS. 1 and 2, the coating head 14 includes a plurality (in this embodiment, five) of discharge nozzles 17. On the (−Z) side end face of each discharge nozzle 17, discharge ports (in FIG. 2, only the discharge ports of the two discharge nozzles 17 are denoted by reference numeral 171) are formed. The same type of organic EL liquid is continuously discharged. In the present embodiment, the distance between the main surface 90 of the substrate 9 and the discharge port 171 is about 0.5 millimeter (mm). The five discharge nozzles 17 are arranged substantially linearly in the X direction (that is, the main scanning direction) and are slightly shifted in the Y direction (that is, the sub scanning direction). In the coating apparatus 1, the positions of the plurality of discharge nozzles 17 in the Y direction can be individually adjusted, and the discharge ports 171 of the five discharge nozzles 17 are arranged at equal intervals in the sub-scanning direction and are adjacent to each other. The distance between the centers of the discharge ports 171 of the two discharge nozzles 17 in the sub-scanning direction is made equal to three times the pitch of the partition walls on the substrate 9 in the Y direction.

  As shown in FIG. 2, each of the (+ X) side and the (−X) side of the coating head 14 has an accordion-shaped member 31 (as will be described later, the organic EL liquid in an atmosphere in the vicinity of the main surface 90 of the substrate 9. Since it is a member that diffuses the solvent component, it is hereinafter referred to as “diffusion member 31”). Specifically, one end of each diffusing member 31 is fixed to the coating head 14 and the other end is supported by a support table 311 (the support table in FIG. 1) provided across the substrate holding unit 11 and the coating head 14. 311 is omitted). Each diffusing member 31 can be expanded and contracted in the main scanning direction. As shown in FIG. 1 and FIG. 3 showing the vicinity of the coating head 14 along the main scanning direction, the diffusion member 31 has a rail 312 extending in the main scanning direction. The + Y) side portion is supported so as to be movable in the main scanning direction. In FIG. 3, illustration of the head moving mechanism 15, the (+ X) side diffusion member 31, and the partition on the substrate 9 is omitted. The distance between the end portion of the diffusing member 31 on the substrate 9 side (or the end surface on the substrate 9 side of the coating head 14 excluding the discharge nozzle 17) and the main surface 90 of the substrate 9 is preferably the main surface 90 of the substrate 9. 2 to 30 times the distance between the nozzle and the discharge port 171 and 10 times (5 mm) in this embodiment.

  With such a configuration, when the coating head 14 moves from the (−X) side to the (+ X) direction, the (−X) side diffusion member 31 extends and the (+ X) side diffusion member 31 extends. Is contracted (see FIG. 5 described later), and when moving from the (+ X) side to the (−X) direction, the (+ X) side diffusing member 31 extends and the (−X) side diffusing member 31 is expanded. Will shrink.

  Next, the application of the organic EL liquid by the coating apparatus 1 will be described. When the organic EL liquid is applied to the application region 91 shown in FIG. 1, the region between the partition walls on the main surface 90 from each discharge nozzle 17 (that is, the region extending in the main scanning direction, hereinafter referred to as “linear” The organic EL liquid is discharged and applied to the “region”. As will be described later, in the coating apparatus 1, in a plurality of linear regions arranged at a constant pitch in the sub-scanning direction (a pitch equal to the partition pitch, hereinafter referred to as “region pitch”), the sub-scanning direction is applied. The organic EL liquid is applied to the linear region that exists every two. That is, two linear regions to which other types of organic EL liquids are applied are sandwiched between two linear regions to which the organic EL liquid is applied by the coating apparatus 1. Yes. Hereinafter, a specific coating operation in the coating apparatus 1 will be described.

  FIG. 4 is a diagram illustrating a flow of application of the organic EL liquid in the coating apparatus 1. In the coating apparatus 1, when the substrate 9 is held by the substrate holding unit 11, an alignment mark formed on the substrate 9 is detected by an alignment mark detection unit (not shown) and is output from the alignment mark detection unit. Based on this, the substrate moving mechanism 12 is driven to move and rotate the substrate 9, and it is located at the coating start position indicated by the solid line in FIG. 1 (step S11). As described above, a plurality of partition walls parallel to each other are arranged on the main surface 90 of the substrate 9, and a linear region is defined as a region between the partition walls on the main surface 90. By arranging at the position, in the coating apparatus 1, a plurality of linear regions each extending in the main scanning direction are arranged and set on the main surface 90 at a constant region pitch in the sub-scanning direction perpendicular to the main scanning direction. In this state, the substrate 9 to be processed is prepared. At this time, the coating head 14 is in the vicinity of the end on the (+ Y) side of the substrate 9 in the sub-scanning direction, and in the main scanning direction, a standby position indicated by a solid line in FIG. 1 and FIG. (Above the liquid receiving part 16 on the (−X) side).

  Subsequently, the discharge of the organic EL liquid is started from the plurality of discharge nozzles 17 (step S12), and further, the head moving mechanism 15 is controlled to move the coating head 14 in the main scanning direction (that is, (− in FIG. 1). X) side to (+ X) side main scanning) is started. As a result, the coating head 14 continues in the main scanning direction while discharging the organic EL liquid continuously (without interruption) from each of the plurality of discharge ports 171 toward the main surface 90 of the substrate 9 at a constant flow rate. The organic EL liquid is applied to the five linear regions of the application region 91 of the substrate 9 in stripes (step S13).

  Then, as shown in FIG. 5, the coating head 14 moves to above the (+ X) side liquid receiving part 16 (that is, the standby position indicated by a two-dot chain line in FIGS. A stripe pattern is formed by the EL liquid. In the following description, a line corresponding to one ejection port 171 in the pattern is referred to as a linear element. Note that the (+ X) side and (−X) side non-application regions (and the (+ Y) side and (−Y) side non-application regions) of the application region 91 in FIG. 1 are not shown. Since it is covered with a mask, the organic EL liquid is not applied directly onto the substrate 9.

  FIG. 6 is a view showing a cross section of the substrate 9 perpendicular to the main scanning direction. In the coating apparatus 1, as described above, a plurality of linear regions (that is, regions on the main surface 90 between the two partition walls 92 adjacent to each other as shown in FIG. The organic EL liquid is applied to the linear regions 93 that are present every two in the sub-scanning direction.

  The organic EL liquid applied on the plurality of linear regions 93 by the plurality of ejection nozzles 17 in the main scan of the coating head 14 is finished drying (that is, evaporation of the solvent from the organic EL liquid) in a short time. However, in the coating apparatus 1, when the coating head 14 moves from the (−X) side to the (+ X) direction, as shown in FIG. When the (−X) side diffusing member 31 extends in the (−X) side space) of the coating head 14 that moves automatically, ambient air is fed into the space. At this time, the upper part of the organic EL liquid discharged onto the substrate 9 is covered with the extended diffusion member 31, so that the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9 is actually stirred. Air flow (that is, air flow toward various directions) is generated. Thereby, in the atmosphere around the organic EL liquid discharged from the plurality of discharge ports 171 onto the plurality of linear regions 93, the solvent component of the volatile organic EL liquid is diffused, and the concentration of the solvent component is made uniform. The organic EL liquid applied on the plurality of linear regions 93 is dried under substantially the same atmosphere (that is, the solvent evaporates from the organic EL liquid). Then, as shown in FIG. 6, the organic EL material is left on the substrate 9 in a semi-dried state (that is, applied), and each linear element 94 becomes a film of the organic EL material. In FIG. 6, the concentration of the solvent component of the organic EL liquid is uniform in the atmosphere around the plurality of linear elements 94 by surrounding the entire plurality of linear elements 94 with a two-dot chain line denoted by reference numeral A1. It shows the state that is made abstract.

  When the coating head 14 moves to the standby position, the substrate moving mechanism 12 is driven, and the substrate 9 moves together with the substrate holder 11 in the (+ Y) direction (ie, the sub-scanning direction) by a distance equal to 15 times the area pitch ( Step S14). At this time, in the coating head 14, the organic EL liquid is continuously discharged from the plurality of discharge nozzles 17 toward the liquid receiving unit 16.

  When the movement of the substrate 9 in the sub-scanning direction is completed, it is confirmed by the control unit 2 whether or not the substrate 9 and the substrate holding unit 11 have moved to the application end position indicated by the two-dot chain line in FIG. 1 (step S15). ). If the application head 14 has not moved to the application end position, the process returns to step S13, and the application head 14 discharges the organic EL liquid from the plurality of discharge nozzles 17 while the (+ X) side of the substrate 9 is in the (−X) direction ( That is, the organic EL liquid is applied to the linear region on the substrate 9 by moving in the main scanning direction (step S13). At this time, as shown in FIG. 2, the (+ X) side diffusing member 31 extends, so that the space behind the coating head 14 in the traveling direction (that is, the (+ X) side of the coating head 14 that moves continuously). The surrounding air is sent to the space 9), and an air flow is generated that agitates the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9. Thereafter, it is confirmed whether or not the substrate 9 has moved in the sub-scanning direction and has moved to the coating end position (steps S14 and S15).

  In the coating apparatus 1, the substrate 9 is relatively moved in the sub-scanning direction every time the coating head 14 is moved in the main scanning direction until the substrate holding unit 11 and the substrate 9 are positioned at the coating end position ( That is, the movement of the coating head 14 in the main scanning direction and the step movement of the substrate 9 toward the (+ Y) side are repeated), whereby the organic EL liquid is three times the area pitch in the coating region 91 of the substrate 9. Are applied in stripes arranged at a pitch equal to (step S13 to S15). In the coating apparatus 1, the direction in which the application of the organic EL liquid proceeds on the substrate 9 in the sub-scanning direction (that is, the relative movement direction of the coating head 14 with respect to the substrate 9) is the movement direction of the substrate 9 by the substrate moving mechanism 12. Is in the opposite direction.

  When the substrate 9 moves to the application end position, the discharge of the organic EL liquid from the plurality of discharge nozzles 17 is stopped (Steps S15 and S16), and the application of the organic EL liquid to the substrate 9 by the coating apparatus 1 is completed. The substrate 9 that has been applied by the coating apparatus 1 is transported to another coating apparatus or the like, and two organic EL liquids other than the organic EL liquid applied by the coating apparatus 1 are applied. Then, after a predetermined process is performed on the substrate 9, an organic EL display device is manufactured in combination with other components.

  By the way, if the organic EL liquid is applied on the substrate 9 by the application apparatus of the comparative example in which the diffusion member 31 is omitted from the application apparatus 1 of FIG. 1, among the plurality (five) of discharge nozzles 17. In the vicinity of the linear element of the organic EL liquid applied by the three discharge nozzles 17 in the vicinity of the center, the concentration of the solvent component of the organic EL liquid in the atmosphere becomes high, and the liquid is applied by the (+ Y) side discharge nozzles 17. Even in the vicinity of the linear element of the organic EL liquid, in the atmosphere due to the influence of the linear element of the organic EL liquid applied by the discharge nozzle 17 closest to the (−Y) side in the main scanning of the coating head 14 just before. The concentration of the solvent component of the organic EL liquid becomes higher.

  However, the discharge nozzle 17 on the (−Y) side (that is, the nozzle on the rear side in the relative movement direction of the substrate in the sub-scanning direction, hereinafter referred to as “rear nozzle”. However, when attention is paid to the coating head 14, On the (−Y) side of the linear element of the organic EL liquid applied by the above (hereinafter, the linear element formed by the rear nozzle is referred to as “rear side linear element”). The other organic EL liquid linear elements are not formed, and the organic EL liquid linear elements applied in parallel by the discharge nozzles 17 in the vicinity of the center are arranged only on the (+ Y) side. . For this reason, in the periphery of the rear linear element applied by the (−Y) side rear nozzle, the linear elements applied by the (+ Y) side discharge nozzle 17 and the three discharge nozzles 17 in the vicinity of the center. The concentration of the solvent component of the organic EL liquid is lower than the surroundings. To be exact, the concentration of the solvent component of the organic EL liquid in the atmosphere on the (−Y) side of the rear linear element is lower than the concentration on the (+ Y) side of the rear linear element around the rear linear element. Become.

  Therefore, the (−Y) side portion of the rear linear element dries much faster than the (+ Y) side portion, and FIG. As shown in A, in the (−Y) side rear linear element 94a formed of a semi-dry organic EL material, the (−Y) side portion (a portion including a square protrusion. (+ Y)). The difference D1 (hereinafter referred to as “edge film thickness difference”) between the film thickness of the part on the side and the film thickness on the (+ Y) side is substantially zero. The dispersion state of the organic EL material having a cross-sectional shape perpendicular to the main scanning direction in the plurality of linear elements 94 is not constant. Note that FIG. In A, by enclosing a part of the rear linear element 94a on the (−Y) side and the other linear element 94 with a two-dot chain line denoted by reference numeral A2, on the (−Y) side of the rear linear element 94a. The state in which the concentration of the solvent component of the organic EL liquid in the atmosphere is different from the concentration on the (+ Y) side of the rear linear element 94a is abstractly shown.

  Then, when the rear linear elements 94a of the organic EL material having a deviation in thickness are formed periodically (that is, every five pieces) in the application region, uneven application (also referred to as stitching). In some cases, the display quality of the organic EL display device after the product becomes a product deteriorates. In the rear linear element, the film thickness of the part on the side of the other linear element formed simultaneously is not necessarily smaller than the film thickness of the part on the opposite side of the part. Depending on the type, the film thickness of the part on the side of the other linear element formed at the same time may be larger than the film thickness of the part on the opposite side to the part.

  If only one nozzle is provided in the coating head, FIG. When coating is performed at the same pitch as in the case of A, a plurality of linear elements on the substrate 9 are formed under substantially constant conditions, and FIG. As shown in B, the cross-sectional shape perpendicular to the main scanning direction in the plurality of linear elements 94 is substantially constant. In this case, the coating unevenness is not recognized, but the time (tact time) required for forming the linear element 94 on the entire substrate 9 becomes long.

  In contrast to the coating apparatus of the comparative example, in the coating apparatus 1 of FIG. 1, a diffusion member 31 that is an air flow generation unit is attached to the coating head 14, and the coating head 14 is moved in the main scanning direction by the head moving mechanism 15. The diffusing member 31 sends air into the space behind the coating head 14 in the traveling direction, and generates an air flow around the organic EL liquid immediately after being discharged onto the substrate 9 (that is, the substrate in one main scan). 9) An air flow is generated around the organic EL liquid discharged on the head 9 until the main scanning is completed. Thus, the organic EL liquid discharged from the plurality of discharge ports 171 is not affected in the atmosphere around the plurality of linear elements 94 formed by the organic EL liquid without affecting the discharge of the organic EL liquid from the coating head 14. The concentration of the solvent component of the EL liquid can be made uniform (that is, the atmosphere can be made uniform), and the uniformity of the drying speed of the organic EL liquid discharged from the plurality of discharge ports 171 can be improved. As a result, the non-uniformity of the cross-sectional shape of the linear element 94 of the organic EL material formed on the substrate 9 (variation in edge film thickness difference) is reduced, and the organic EL display manufactured using the substrate 9 is achieved. It is possible to suppress deterioration in display quality due to uneven application in the apparatus.

  In addition, since the airflow generation portion is the bellows-like diffusion member 31, air can be easily fed into the space on the rear side in the traveling direction of the coating head 14. Further, in the coating apparatus 1, the coating head 14 discharges the organic EL liquid onto the substrate 9 in the forward path and the backward path of movement in the main scanning direction, and the two diffusion members 31 move in the forward path and the backward path of the movement of the coating head 14. In both cases, an air flow is generated around the organic EL liquid immediately after being discharged onto the substrate 9. Thereby, the organic EL liquid can be applied over a wide area on the substrate 9 in a short time while reducing the non-uniformity of the cross-sectional shape of the linear element 94 of the organic EL material formed on the substrate 9 ( That is, a plurality of linear elements 94 can be formed over a wide range on the substrate 9 in a short time.)

  FIG. 8 is a plan view showing the vicinity of the coating head 14 according to the second embodiment of the present invention, and FIG. 9 is a cross-sectional view of the blower member 32 at the position of the arrow AA in FIG. In the coating apparatus 1 according to the present embodiment, the diffusing member 31, the support base 311 and the rail 312 are omitted from the coating apparatus 1 shown in FIG. Other configurations are the same as those of the coating apparatus 1 of FIG.

  As shown in FIG. 8, the two air blowing members 32 are provided on the sub-scanning direction side ((+ Y) side) of the coating head 14, and near the (+ X) side and (−X) side ends of the coating head 14. Each is arranged. As shown in FIG. 8 and FIG. 9, each air blowing member 32 has two plate-like side wall plates 322 that have an outer shape of a right triangle and are arranged in parallel with a gap therebetween. Are arranged so that the two sides excluding the hypotenuse are along the X direction or the Z direction while the hypotenuse is located on the center side of the coating head 14. A plate-shaped member 321 (hereinafter referred to as “inclined plate 321”) is attached to the oblique side portion of the two side wall plates 322 facing each other, and the inclined plate 321 moves toward the center of the coating head 14 in the X direction. Inclined so that the distance to 9 decreases.

  When the organic EL liquid is applied by the coating apparatus 1 having the blower member 32 of FIG. 8, the substrate 9 is moved to the application start position (FIG. 4: step S11), and the organic EL liquid from the discharge nozzle 17 is used. (Step S12), the coating head 14 performs main scanning from the (−X) side to the (+ X) direction by the head moving mechanism 15 to apply the organic EL liquid onto the substrate 9 (step S12). S13).

  At this time, the air entering the inside of the (+ X) side blowing member 32 with the main scanning of the coating head 14 (that is, the air on the front side in the traveling direction of the coating head 14) is denoted by reference numeral 81a in FIG. As shown by the attached arrow (however, in FIG. 9, the direction of the X direction is opposite to that of FIG. 8), the surface 321a of the inclined plate 321 facing the substrate 9 side (the traveling direction of the coating head 14). This is the front surface and is hereinafter referred to as “guide surface 321a”). In the coating apparatus 1, as in the case of the diffusing member 31 in the first embodiment, the distance between the coating head 14 and the inclined plate 321 and the main surface 90 of the substrate 9 is very small. The air flowing toward the surface spreads on the main surface 90 and the air is sent between the coating head 14 and the substrate 9, whereby the airflow that agitates the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9 Occurs. Thereby, the concentration of the solvent component of the organic EL liquid is made uniform in the atmosphere around the organic EL liquid discharged from the plurality of discharge ports 171 onto the plurality of linear areas, and the organic EL liquid on the plurality of linear areas is obtained. Dries under almost the same atmosphere.

  Thereafter, the substrate 9 moves in the sub-scanning direction (step S14), and when it is confirmed that the substrate 9 has not moved to the coating end position (step S15), the coating head 14 moves from the (+ X) side to (-X). The organic EL liquid is applied on the substrate 9 by performing main scanning in the direction) (step S13). At this time, the blowing member 32 is attached to the front side in the intermittent relative movement direction of the substrate 9 by the substrate moving mechanism 12 (rear side in the relative movement direction of the coating head 14 when focusing on the coating head 14). Accordingly, air in the vicinity of the organic EL liquid applied on the substrate 9 in the main scanning of the immediately preceding application head 14, that is, air having a relatively high concentration of the solvent component of the organic EL liquid is blown on the (−X) side. The member 32 enters the inside of the member 32 and is guided to the substrate 9 side by the guide surface 321a of the inclined plate 321 as indicated by an arrow denoted by reference numeral 81b in FIG. An air flow is generated to stir the atmosphere around the organic EL liquid.

  In the coating apparatus 1, each time the movement of the coating head 14 in the main scanning direction is completed until the substrate 9 is positioned at the coating end position, the substrate 9 is relatively moved in the sub-scanning direction. In 91, the organic EL liquid is applied in stripes arranged at a pitch equal to three times the area pitch (steps S13 to S15). When the substrate 9 moves to the application end position, the discharge of the organic EL liquid from the plurality of discharge nozzles 17 is stopped (steps S15 and S16), and the application of the organic EL liquid to the substrate 9 by the coating apparatus 1 is completed.

  As described above, in the coating apparatus 1 according to the second embodiment, the air blowing member 32 that is an air flow generation unit is attached to the coating head 14 and moved in the main scanning direction together with the coating head 14 by the head moving mechanism 15. By doing so, an air flow is generated around the organic EL liquid immediately after the blowing member 32 is discharged onto the substrate 9. Thereby, in the atmosphere around the organic EL liquid discharged from the plurality of discharge ports 171, it is possible to realize a uniform concentration of the solvent component of the organic EL liquid with a simple structure. The uniformity of the drying rate of the organic EL liquid discharged from 171 can be improved. As a result, the non-uniformity of the cross-sectional shape of the linear element of the organic EL material formed on the substrate 9 is reduced, and the display quality deteriorates due to coating unevenness in the organic EL display device manufactured using the substrate 9. Can be suppressed.

  Further, in the coating apparatus 1, the coating head 14 discharges the organic EL liquid onto the substrate 9 in the forward path and the backward path of movement in the main scanning direction, and the two blower members 32 move the forward path and the backward path of the movement of the coating head 14. In both cases, an air flow is generated around the organic EL liquid immediately after being discharged onto the substrate 9. Thereby, a large number of linear elements can be formed on the substrate 9 in a short time while reducing the non-uniformity of the cross-sectional shape of the linear elements of the organic EL material formed on the substrate 9.

  FIG. 10 is a perspective view showing another example of the air blowing member. In FIG. 10, the coating head 14 is indicated by a two-dot chain line. In the coating head 14 of FIG. 10, the blower member 32 is attached to the main scanning direction (X direction) side, and actually is attached to both the (+ X) side and the (−X) side of the coating head 14. Accordingly, as indicated by an arrow denoted by reference numeral 82 in FIG. 10, the blower member 32 causes the coating head 14 and the substrate 9 to move between the coating head 14 and the substrate 9 (that is, in FIG. 10). It becomes possible to send air directly into the space on the (−Z) side of the coating head 14. As a result, it is possible to efficiently stir the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9 and improve the uniformity of the drying speed of the organic EL liquid discharged from the plurality of discharge ports 171. Is done. As described above, in the actual coating apparatus 1, since the discharge port 171 of the discharge nozzle 17 is provided close to the main surface 90 of the substrate 9, it is directly between the coating head 14 and the substrate 9. Application of the organic EL liquid is not disturbed by the air that is sent.

  FIG. 11 is a perspective view showing still another example of the blowing member, and FIG. 12 is a plan view showing the coating head 14 and the blowing member 32a. In FIG. 12, the linear elements 94 formed on the substrate 9 are indicated by thin lines while omitting the illustration of the partition walls on the substrate 9 (the same applies to FIGS. 13 and 16 described later).

  The air blowing member 32a in FIG. 11 is a plate-like member, and the normal line of one main surface is parallel to the main surface of the substrate 9 (that is, parallel to the XY plane in FIG. 11) and in the main scanning direction (X direction). It is inclined with respect to the coating head 14 and attached to the sub-scanning direction (Y direction) side. Actually, as shown in FIG. 12, two air blowing members 32a are attached to the vicinity of the (+ X) side and (−X) side ends of the coating head 14, and each air blowing member 32a is in the main scanning direction. With respect to the end of the coating head 14, the substrate 9 tilts away from the coating head 14, and at least a part thereof is closer to the substrate 9 than the lower surface of the coating head 14 (however, the discharge nozzle 17 is not included; the same applies hereinafter). It is fixed to be positioned.

  In the coating apparatus 1 having the air blowing member 32a, when the coating head 14 moves in the (−X) direction from the (+ X) side, as indicated by an arrow denoted by reference numeral 83 in FIGS. The air is guided between the coating head 14 and the substrate 9 (that is, the space on the (−Z) side of the coating head 14 in FIG. 11) by the (−X) side surface of the blowing member 32 a on the −X) side. . As a result, an air flow is generated between the coating head 14 and the substrate 9, the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9 is stirred, and the organic EL discharged from the plurality of discharge ports 171 is stirred. In the atmosphere around the liquid, the concentration of the solvent component of the organic EL liquid is made uniform. When the coating head 14 moves from the (−X) side in the (+ X) direction, air is sent between the coating head 14 and the substrate 9 by the (+ X) side blowing member 32a.

  In the coating apparatus 1, as shown in FIG. 13, each blowing member 32 a may be attached so as to be inclined away from the coating head 14 toward the center of the coating head 14 in the main scanning direction. Even in this case, as indicated by an arrow denoted by reference numeral 84 in FIG. 13, the atmosphere around the organic EL liquid immediately after being discharged onto the substrate 9 by sending air between the coating head 14 and the substrate 9. Can be stirred.

  FIG. 14 is a perspective view showing still another example of the air blowing member. As shown in FIG. 14, the air blowing member 32b is attached to the substrate 9 side of the coating head 14 in the vicinity of each end in the main scanning direction (X direction) of the coating head 14 (however, in FIG. 14), the blower member 32b has a shape in which the width in the sub-scanning direction (Y direction) gradually increases toward the center of the coating head 14 in the main scanning direction. ing. When the coating head 14 moves in the (−X) direction from the (+ X) side in FIG. 14, as shown by the arrow denoted by reference numeral 85 in FIG. 14, from the center of the coating head 14 in the sub-scanning direction. Air is guided by the blowing member 32b so as to leave. As a result, an air vortex is actually generated on the (+ X) side of the air blowing member 32b (the rear side in the traveling direction of the coating head 14), and around the organic EL liquid immediately after being discharged onto the substrate 9 The atmosphere is stirred. As a result, it is possible to improve the uniformity of the drying speed of the organic EL liquid discharged from the plurality of discharge ports 171.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications are possible.

  In the first embodiment, the diffusing member 31 is supported by the rail 312, but the diffusing member 31 may be supported by other methods. For example, as shown in FIG. 15, the support base 311 is raised in the (+ Z) direction, and one end of a plurality of stretchable string members 313 is fixed to the support portion 311 a extending in the X direction of the support base 311, and the other end Is fixed to the diffusing member 31, so that the diffusing member 31 is supported at a plurality of locations. Further, instead of the string-like member 313, a rod-like member is used. One end of the rod-like member is supported by the support portion 311a so as to be movable in the X direction, and the other end is fixed to the diffusion member 31. May be supported at a plurality of locations.

  In the first embodiment, when the coating head 14 moves in the main scanning direction, air is sent into the space on the rear side in the traveling direction of the coating head 14 by the diffusion member 31. For example, FIG. As shown in FIG. 13, a plate-like member 31a similar to the air blowing member 32a in FIG. 13 is disposed at a position away from the application head 14 in the main scanning direction and is fixed to the application head 14 (actually not shown). The support member is fixed to the coating head 14 on the (+ Z) side of the lower surface of the coating head 14.) When the coating head 14 moves in the (−X) direction from the (+ X) side, FIG. As indicated by an arrow denoted by reference numeral 86 in FIG. 16, air may be sent into the space behind the coating head 14 in the traveling direction.

  In the second embodiment, by providing the two blower members 32, 32a, 32b, the coating head 14 is discharged onto the substrate 9 in each of the forward and backward movements of the reciprocating movement in the main scanning direction. For example, as shown in FIG. 17, two guide surfaces equivalent to the two guide surfaces 321a in the two air blowing members 32 in FIG. 9 are realized. One air blowing member 32c having 321c is provided in the sub-scanning direction side of the coating head 14 in the vicinity of the central portion of the coating head 14, so that the coating head 14 is reciprocally moved in the main scanning direction in each of the forward path and the backward path. Alternatively, an air flow may be generated around the organic EL liquid immediately after being discharged onto the substrate 9.

  8 and 9, the guide surface 321a of the inclined plate 321 is surrounded by the side wall plate 322, so that air can be efficiently guided to the substrate 9 side. Depending on the design, the side wall plate 322 may be omitted.

  8, 12, and 13 may be arranged on the (−Y) side of the coating head 14 (that is, on the rear side in the intermittent relative movement direction of the substrate 9 by the substrate moving mechanism 12). . However, in order to further uniform the concentration of the solvent component of the organic EL liquid in the atmosphere around the organic EL liquid immediately after being discharged from the plurality of discharge ports 171, the substrate 9 is intermittently moved relative to the substrate 9 by the substrate moving mechanism 12. It is preferable that the blowing member 32a is attached to the front side in the moving direction, and air having a high concentration of the solvent component is sent between the coating head 14 and the substrate 9.

  In the first and second embodiments, a plurality of linear elements 94 formed of an organic EL liquid containing a luminescent material of the same color are arranged on the main surface 90 at a pitch three times the area pitch. Thus, it is realized that a pattern of a light emitting material is appropriately formed on the substrate 9. However, a material containing a hole transporting material in addition to a volatile solvent (for example, water) is formed on the substrate 9 as a fluid material. It may be applied. Also in this case, in the coating apparatus, it is possible to improve the uniformity of the drying speed of the flowable material discharged from the plurality of discharge ports 171 and to suppress the variation in the cross-sectional shape of the linear element after drying, In the organic EL display device, it is possible to suppress deterioration in display quality depending on variations in the cross-sectional shape of the hole transport layer. The “hole transport material” is a material for forming a hole transport layer of the organic EL display device, and the “hole transport layer” is a hole to the organic EL layer formed of the organic EL material. This includes not only a hole transport layer in a narrow sense that transports, but also includes a hole injection layer that injects holes.

  In the coating apparatus, for example, three discharge nozzles 17 are provided in the coating head 14, and three types of organic EL having different colors from red (R), green (G), and blue (B) from these discharge nozzles 17 are provided. Three types of organic EL liquids each containing a material may be simultaneously ejected and applied to the substrate 9. Further, in the coating head 14, as long as there are two or more discharge nozzles 17 that discharge the fluid material, other numbers may be used.

  In the coating apparatus, instead of moving the substrate 9 and the substrate holding unit 11 by the substrate moving mechanism 12, the coating head 14 moves in the sub-scanning direction, so that the substrate 9 moves relative to the coating head 14 in the sub-scanning direction. May be performed.

  In the substrate 9 to be processed in the above embodiment, the organic EL liquid is applied on the substrate 9 on which the partition wall is formed, but the coating material is applied on the substrate 9 on which the partition wall is not formed. Is also possible.

  The coating device can also be used when a plurality of organic EL display devices are manufactured from a single substrate (so-called multi-surface processing). Further, by applying a fluid material containing a pixel forming material (organic EL material or hole transport material) for an organic EL display device as a material to be applied on the substrate 9 onto the substrate 9 using an application device, Although the deterioration of display quality due to coating unevenness in the EL display device is suppressed, the nozzle printing type coating device is a coloring material for a substrate for other flat display devices such as a liquid crystal display device and a plasma display device, for example. Or a flowable material including other types of pixel forming materials such as fluorescent materials. Also in this case, in the flat display device, it is possible to suppress deterioration in display quality due to coating unevenness.

  Moreover, the coating device may be used for coating various types of fluid materials on various substrates such as a semiconductor substrate in addition to the substrate for a flat display device.

It is a top view which shows the coating device which concerns on 1st Embodiment. It is a front view of a coating device. It is a side view which shows the application head vicinity. It is a figure which shows the flow of application | coating of the organic EL liquid in a coating device. It is a figure which shows the coating device in the middle of application | coating of organic EL liquid. It is a figure which shows the cross section of the linear element on a board | substrate. It is a figure which shows the cross section of the linear element formed with the coating device of a comparative example. It is a figure which shows the cross section of the linear element formed with the coating device of another comparative example. It is a top view which shows the coating head vicinity which concerns on 2nd Embodiment. It is sectional drawing of a ventilation member. It is a perspective view which shows the other example of a ventilation member. It is a perspective view which shows the other example of a ventilation member. It is a top view which shows an application head and a ventilation member. It is a top view which shows the other example of a ventilation member. It is a perspective view which shows the other example of a ventilation member. It is a figure which shows the other example of support of a diffusion member. It is a figure which shows the other example which sends air into the space of the back side of the advancing direction of an application head. It is a figure which shows the further another example of a ventilation member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Application | coating apparatus 9 Substrate 11 Substrate holding | maintenance part 12 Substrate moving mechanism 14 Coating head 15 Head moving mechanism 31 Diffusion member 31a Plate-shaped member 32, 32a-32c Blowing member 94 Linear element 171 Discharge port

Claims (9)

An application device for applying a flowable material to a substrate,
A substrate holder for holding the substrate;
A discharge mechanism for discharging a flowable material including a volatile solvent and a material applied on the substrate toward the substrate from a plurality of discharge ports arranged at equal intervals in a sub-scanning direction parallel to the substrate; ,
A main scanning mechanism that moves the ejection mechanism in a main scanning direction perpendicular to the sub-scanning direction and parallel to the substrate;
A sub-scanning mechanism that moves the substrate relative to the discharge mechanism in the sub-scanning direction each time the movement of the discharge mechanism in the main scanning direction is completed;
An airflow generation unit that is attached to the discharge mechanism and generates an airflow around the flowable material immediately after being discharged onto the substrate by the movement of the discharge mechanism in the main scanning direction by the main scanning mechanism. When,
A coating apparatus comprising: The coating apparatus according to claim 1,
The coating apparatus according to claim 1, wherein the air flow generation unit sends air into a space on the rear side in the traveling direction of the ejection mechanism by the movement of the ejection mechanism in the main scanning direction by the main scanning mechanism. The coating apparatus according to claim 2,
The air flow generation unit is a bellows-like member that extends in a space behind the discharge mechanism in the traveling direction by the movement of the discharge mechanism in the main scanning direction and feeds ambient air into the space. An applicator characterized by. The coating apparatus according to claim 1,
The coating apparatus according to claim 1, wherein the air flow generation unit is a blowing member that sends air between the ejection mechanism and the substrate by moving in the main scanning direction together with the ejection mechanism by the main scanning mechanism. The coating apparatus according to claim 4,
The coating apparatus, wherein the blower member is attached to the sub-scanning direction side of the discharge mechanism. The coating apparatus according to claim 5,
The coating apparatus, wherein the blower member is attached to a front side in an intermittent relative movement direction of the substrate by the sub-scanning mechanism. The coating apparatus according to claim 4,
The coating apparatus, wherein the blowing member is attached to the main scanning direction side of the discharge mechanism. A coating apparatus according to any one of claims 1 to 7,
The discharge mechanism discharges the flowable material onto the substrate in a forward path and a return path of movement in the main scanning direction;
The coating apparatus, wherein the air flow generation unit generates the air flow in both the forward path and the return path of movement of the discharge mechanism. A coating apparatus according to any one of claims 1 to 8,
The fluidizing material includes an organic EL material or a hole transport material for an organic EL display device.

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