JP2011050892A - Coating apparatus and coating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating apparatus and a coating method suppressing the occurrence of abnormal ejection due to the drying of coating liquid attached to an ejection surface of a coating head. <P>SOLUTION: The coating apparatus 1 includes: a stage 2 on which an object to be coated is loaded; a coating head 3 which has an ejection surface M1 in which ejection holes for ejecting droplets are formed and which ejects coating liquid from the ejection holes toward the object to be coated on the stage 2; a moving mechanism 7 which relatively moves the stage 2 and the coating head 3 in the face direction of the stage 2; and an ejection stabilizing device 6 which includes a liquid-absorbing absorption body 11 having a contact surface M2 coming in contact with the ejection surface M1 of the coating head 3 and wets the whole surface of the contact surface M2 of the absorption body 11 and brings the wet contact surface M2 into contact with the ejection surface M1 of the coating head 3 to wet the whole surface of the ejection surface M1 of the coating head 3. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a coating apparatus and a coating method for coating a coating target by discharging droplets.

  The coating device is used when manufacturing a display device or a semiconductor device, and when forming a color filter or when forming a functional thin film such as an alignment film or a resist on a substrate such as a glass substrate or a semiconductor wafer. It is used for etc.

  This coating apparatus includes a coating head that discharges (sprays) a coating liquid as droplets from a plurality of discharge holes (nozzles) toward a coating target such as a substrate. Each ejection hole is formed in a straight line on the ejection surface (orifice surface) of the coating head. In such a coating apparatus, a plurality of droplets are sequentially landed on the coating surface of the coating object by the coating head while relatively moving the coating object on the stage and the coating head (for example, Patent Document 1). reference).

Japanese Patent Laid-Open No. 2003-230858

  However, in the above-described coating apparatus, when the coating liquid adhering to the vicinity of the ejection hole of the coating head is dried and becomes a solidified product, ejection abnormalities such as a discharge bend occur due to the solidified material. Even when the coating liquid adheres to a position away from the ejection holes on the ejection surface of the coating head, if the coating liquid dries and becomes a solidified product, the solidified product is wiped (wiping operation) and the ejection holes of the coating head are removed. Since it may move to the vicinity, discharge abnormalities, such as a discharge bending, will generate | occur | produce due to the solidified substance.

  Therefore, it is important to prevent liquid drying on the discharge surface of the coating head, and the surface of the discharge surface of the coating head is wetted to prevent liquid drying. It is difficult to keep the entire surface uniform. Since the wet state of the surface of the discharge surface has a great influence on the liquid discharge performance, abnormal discharge occurs when the wet state is not uniform and liquid drying occurs.

  The present invention has been made in view of the above, and an object of the present invention is to provide a coating apparatus and a coating method capable of suppressing the occurrence of abnormal discharge due to drying of the coating liquid adhering to the ejection surface of the coating head. That is.

  A first feature according to an embodiment of the present invention is that a coating apparatus includes a stage on which a coating target is placed and a discharge surface on which discharge holes for discharging droplets are formed. A coating head that discharges the coating liquid as droplets from the discharge hole toward the coating object, a moving mechanism that relatively moves the stage and the coating head in the surface direction of the stage, and a contact surface that contacts the discharge surface of the coating head A discharge stabilizer that wets the entire contact surface of the absorber and wets the entire discharge surface of the coating head by contacting the wet contact surface and the discharge surface of the coating head. It is to provide.

  The second feature according to the embodiment of the present invention is that the application target on the stage has a stage on which the application target is placed and a discharge surface on which discharge holes for discharging droplets are formed. The coating liquid is applied to the coating object on the stage using a coating head that discharges the coating liquid as droplets from the discharge hole and a moving mechanism that relatively moves the stage and the coating head in the surface direction of the stage. A coating method, using a liquid absorbent absorber having a contact surface that contacts the ejection surface of the coating head, wets the entire contact surface of the absorber, and the wet contact surface and the ejection surface of the coating head It is to wet the entire discharge surface of the coating head by bringing it into contact.

  According to the present invention, it is possible to suppress the occurrence of ejection abnormality due to the drying of the coating liquid adhering to the ejection surface of the coating head.

It is a schematic diagram which shows schematic structure of the coating device which concerns on the 1st Embodiment of this invention. FIG. 2 is a cross-sectional view taken along line A1-A1 of FIG. FIG. 3 is a cross-sectional view taken along line A2-A2 of FIG. It is explanatory drawing for demonstrating the relative size of the discharge surface of the coating head with which the coating device shown in FIG. 1 is provided, and the absorber of a discharge stabilization apparatus. It is a schematic diagram of the 1st process for demonstrating the flow of the wetting operation | movement which the discharge stabilizer provided in the coating device shown in FIG. 1 performs. It is a schematic diagram of a 2nd process. It is a schematic diagram of a 3rd process. It is a schematic diagram of a 4th process. It is a flowchart which shows the flow of the coating process which the coating device shown in FIG. 1 performs. It is a perspective view which shows the one part schematic structure of the discharge stabilization apparatus with which the coating device which concerns on the 2nd Embodiment of this invention is provided.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 to 3, the coating apparatus 1 according to the first embodiment of the present invention is such that the substrate K as a coating target is in a horizontal state (in FIG. 1, the X axis direction and the Y axis perpendicular thereto) Stage 2 placed in a state along the direction), a coating head 3 that discharges the coating liquid as droplets toward the substrate K on the stage 2, and an X-axis that moves the coating head 3 in the X-axis direction. The moving mechanism 4, the support member 5 that supports the coating head 3 together with the X-axis moving mechanism 4, the discharge stabilizing device 6 that stabilizes the discharge of the coating head 3, and the stage 2 and the discharge stabilizing device 6 are individually provided in the Y-axis direction. A Y-axis moving mechanism 7 to be moved, a support member 5 and a gantry 8 that supports the Y-axis moving mechanism 7, and a control unit 9 that controls each part are provided.

  The stage 2 is a moving table on which a substrate K such as a glass substrate is placed, and is provided on the upper surface of the gantry 8 via the Y-axis moving mechanism 7. The substrate K is placed on the stage 2 by its own weight. However, the present invention is not limited to this. For example, in order to hold the substrate K, a mechanism such as an electrostatic chuck or an adsorption chuck may be provided. .

  The coating head 3 is a discharge head that is disposed on the stage 2 via the X-axis moving mechanism 4 on the support member 5 and discharges a coating liquid such as ink as droplets. In addition, a coating liquid is supplied through piping, such as a tube, from the liquid tank which accommodates the coating liquid. This coating solution is a solution composed of a solute that remains as a residue on the substrate K and a solvent that dissolves (disperses) the solute. For example, when a functional thin film such as an alignment film or a resist is formed on the substrate K, a polyimide (PI) solution is used as the coating solution.

  The coating head 3 has a plurality of ejection holes (orifices) 3a for ejecting droplets (see FIG. 4), and incorporates a plurality of piezoelectric elements respectively corresponding to the ejection holes 3a. The coating head 3 is electrically connected to the control unit 9, and its driving is controlled by the control unit 9, and droplets are ejected from each ejection hole 3 a in response to application of a driving voltage to each piezoelectric element. Each discharge hole 3a is arranged in a line or two lines in a straight line at a predetermined pitch (interval) (two lines in FIG. 4), and is formed on the discharge surface (orifice surface) M1 of the coating head 3. For example, the number of discharge holes 3a is about several tens to several hundreds, the diameter of the discharge holes 3a is about several μm to several tens of μm, and the pitch of the discharge holes 3a is several tens μm to several hundreds of μm. Degree.

  The X-axis movement mechanism 4 is provided on the support member 5 and is a movement mechanism that moves the coating head 3 in the X-axis direction along the coating surface of the substrate K on the stage 2. The X-axis moving mechanism 4 is electrically connected to the control unit 9 and its driving is controlled by the control unit 9. As the X-axis moving mechanism 4, for example, a feed screw mechanism using a servo motor as a driving source, a moving mechanism using a linear motor as a driving source, or the like is used.

  The support member 5 is formed in a gate shape that is long in the X-axis direction, and is provided on the upper surface of the gantry 8 so as to straddle the stage 2 and the Y-axis moving mechanism 7. The beam portion of the support member 5 is parallel to the X-axis direction and is horizontal to the mounting surface of the stage 2, and the leg portion of the support member 5 is fixed to the gantry 8.

  The discharge stabilizing device 6 includes a discharge stabilizing tank 6a and a tank moving mechanism 6b that moves the discharge stabilizing tank 6a in the Z-axis direction. The discharge stabilizing device 6 is provided on the upper surface of the gantry 8 via the Y-axis moving mechanism 7 and is formed to be movable in the Y-axis direction.

  As shown in FIG. 3, the discharge stabilization tank 6 a has a first container H <b> 1 that functions as a receiving tray that receives droplets discharged by a dummy discharge operation (flushing operation) of the application head 3, and has a liquid absorption property for the application liquid. It has the 2nd container H2 which accommodates the absorber 11. FIG. The discharge stabilization tank 6a is long in the X-axis direction, which is the moving direction of the coating head 3 (see FIG. 2), and is formed in a box shape that opens upward, and the discharge stabilization tank 6a extends in the X-axis direction. The first container H1 and the second container H2 are formed by being partitioned by the plate.

  In the second container H2, a holding member 12 that holds the absorber 11 is provided along the X-axis direction so as to be rotatable by the rotary shaft 13. The holding member 12 is formed in a prismatic shape, and a rotating shaft 13 is fixed to the holding member 12. The rotary shaft 13 is connected to a rotary drive unit such as a motor serving as a drive source. The rotation drive unit is electrically connected to the control unit 9, and the drive is controlled by the control unit 9.

  The tank moving mechanism 6b is provided on the Y-axis moving mechanism 7 so as to be movable in the Y-axis direction. The tank moving mechanism 6b is a Z-axis moving mechanism that supports the discharge stabilizing tank 6a so as to be movable in the Z-axis direction and moves the discharge stabilizing tank 6a in and out of the coating head 3 in the Z-axis direction. This is an absorber moving mechanism that makes the absorber 11 in the discharge stabilizing tank 6a contact and separate in the Z-axis direction with respect to the discharge surface M1 of the coating head 3. The tank moving mechanism 6 b is electrically connected to the control unit 9, and its driving is controlled by the control unit 9. As the tank moving mechanism 6b, for example, a feed screw mechanism using a cylinder or a servo motor as a drive source is used.

  The Y-axis moving mechanism 7 is a moving mechanism that guides the stage 2 and the discharge stabilizing device 6 in the Y-axis direction and moves them individually, and is fixed to the upper surface of the gantry 8. The Y-axis moving mechanism 7 is electrically connected to the control unit 9 and its driving is controlled by the control unit 9. As the Y-axis moving mechanism 7, for example, a feed screw mechanism using a servo motor as a driving source, a moving mechanism using a linear motor as a driving source, or the like is used.

  The gantry 8 is a support base that is installed on the floor surface and supports the support member 5, the Y-axis movement mechanism 7, and the like at a predetermined height position from the floor surface. The upper surface of the gantry 8 is formed into a flat surface, and the support member 5 and the Y-axis moving mechanism 7 are placed on the upper surface of the gantry 8. A control unit 9 is provided inside the gantry 8.

  The control unit 9 includes a microcomputer that centrally controls each unit, a storage unit that stores application information and various programs related to application, and an operation unit that receives operations from an operator. The application information includes a predetermined application pattern such as a dot pattern, information on the ejection frequency of the application head 3 and the moving speed of the substrate K, and the like. This application information is stored in advance in the storage unit through an input operation to the operation unit, data communication, or mediation of a portable storage device. Note that a memory, a hard disk drive (HDD), or the like is used as the storage unit.

  The controller 9 controls the coating head 3 and the Y-axis moving mechanism 7 based on the coating information when performing the coating operation, and controls the ejection stabilizing device 6 and the Y-axis moving mechanism 7 when performing the stable discharging operation. Control. Here, the application operation is an operation for applying droplets to the substrate K, and the ejection stabilization operation is a dummy ejection operation (flushing operation), a wiping operation (wiping operation), or the like.

  Next, the aforementioned absorber 11 will be described in detail.

  As shown in FIG. 4, the contact surface M <b> 2 of the absorber 11 is formed to have substantially the same size as the ejection surface M <b> 1 of the coating head 3. The width of the contact surface M2 in the X-axis direction and the width of the discharge surface M1 in the X-axis direction are substantially the same length L1, and the width of the contact surface M2 in the Y-axis direction and the width of the discharge surface M1 in the Y-axis direction are substantially the same. The length is L2. The contact surface M2 is a surface that contacts the ejection surface M1 of the coating head 3 (the surface of the absorber 11) when the absorber 11 is raised by the tank moving mechanism 6b.

  Here, normally, due to the structure of the coating head 3, the width in which the discharge holes 3a are arranged in the X-axis direction or the Y-axis direction, that is, the discharge width in the X-axis direction is a length L1a that is smaller than the width L1 in the X-axis direction of the discharge surface M1. Thus, the discharge width in the Y-axis direction is a length L2a that is smaller than the width L2 in the Y-axis direction of the discharge surface M1. For this reason, there are regions where the ejection holes 3a are not present at both ends in the X-axis direction and the Y-width direction of the coating head 3, and in particular, these regions are at both ends in the X-axis direction compared to both ends in the Y-axis direction. growing.

  The absorbent body 11 is wetted by the coating liquid and is moved in the Z-axis direction by the tank moving mechanism 6b to come into contact with the ejection surface M1 of the coating head 3, and the Y-axis movement mechanism 7 while contacting the ejection surface M1. By moving in the Y-axis direction, the discharge surface M1 of the coating head 3 is appropriately wetted. At this time, the contact surface M2 of the absorber 11 is in a state of absorbing the coating liquid over the entire surface. As the absorbent body 11, liquid absorbability with respect to the coating liquid to be used is considered, and for example, a fiber member or a porous member is used.

  The coating liquid is supplied to the entire contact surface M2 of the absorber 11 by the coating head 3. That is, the coating head 3 is separated from the absorber 11 by a predetermined distance, and in this state, droplets are ejected from the ejection holes 3a toward the contact surface M2 of the absorber 11 and land on the contact surface M2 of the absorber 11. . The coating liquid as the landed droplets is sucked and stored by the absorber 11 from the contact surface M2.

  In the discharge operation (wetting operation) of the coating head 3 with respect to the absorber 11, the relationship between the width L1 of the absorber 11 in the X-axis direction and the discharge width L1a of the coating head 3 in the X-axis direction, From the relationship between the width L2 in the Y-axis direction and the discharge width L2a in the Y-axis direction of the coating head 3, the coating head 3 and the absorber 11 may be relatively moved.

  For example, as shown in FIG. 5, the coating head 3 has a state in which the discharge surface M1 faces the contact surface M2 of the absorber 11 by about a quarter (a state in which about half of the discharge holes 3a face the absorber 11). That is, from the state in which the upper row of discharge holes 3a faces the upper end of the contact surface M2 and the right end of the row of discharge holes 3a is located at the center of the contact surface, the X axis moving mechanism 4 While moving in the right direction of the arrow in the figure, the droplets are sequentially ejected from each ejection hole 3a, and the position of the two-dot chain line in the figure (position where the left end of the row of ejection holes 3a reaches the center of the contact surface) Move up.

Next, as shown in FIG. 6, the absorber 11 has the contact surface M <b> 2 opposed to the ejection surface M <b> 1 of the coating head 3 (about half of the ejection holes 3 a faces the absorber 11). ( I.e., a state where the upper row of discharge holes 3a faces the upper end of the contact surface M2 and the left end of the row of discharge holes 3a is located at the center of the contact surface), As the device 6 moves, it moves upward in the direction of the arrow in the Y-axis direction and moves to the position of the two-dot chain line in the drawing (the position where the lower row of the discharge holes 3a faces the lower end of the contact surface). At this time, the coating head 3 sequentially discharges droplets from the respective discharge holes 3a.

  Next, as shown in FIG. 7, the coating head 3 has the ejection surface M <b> 1 opposed to the contact surface M <b> 2 of the absorber 11 by about a quarter (about half of the ejection holes 3 a opposed to the absorber 11. State, that is, a state in which the lower row of the discharge holes 3a is opposed to the lower end of the contact surface M2 and the left end of the row of the discharge holes 3a is located at the center of the contact surface) While moving to the left of the arrow in the figure, droplets are sequentially ejected from each ejection hole 3a, and the position of the two-dot chain line in the figure (position where the right end of the row of ejection holes 3a reaches the center of the contact surface) Move up.

  Finally, as shown in FIG. 8, the absorber 11 has the contact surface M <b> 2 opposed to the ejection surface M <b> 1 of the coating head 3 (about half of the ejection holes 3 a faces the absorber 11). A state where the discharge holes 3a in the lower row face the lower end portion of the contact surface M2 and the right end portion of the row of the discharge holes 3a is located at the center portion of the contact surface)). 6 moves downward in the direction of the arrow in the Y-axis direction to the position of the two-dot chain line in the drawing (the position where the upper row of discharge holes 3a faces the upper end of the contact surface). At this time, the coating head 3 sequentially discharges droplets from the respective discharge holes 3a.

  In order to obtain a desired wet state on the contact surface M2 of the absorber 11 from each discharge hole 3a of the coating head 3 during the relative movement between the coating head 3 and the absorber 11 in the operation of FIGS. Droplets are ejected at a preset ejection amount per droplet and the number of ejections per unit time. Note that when the relative movement direction of the coating head 3 and the absorber 11 is switched, the relative movement of both of them temporarily stops. Therefore, even if the discharge of the coating liquid from each discharge hole 3a is stopped during this stop period. It is good, and it is good also as discharge amount and discharge frequency smaller than during relative movement.

  In this way, the coating head 3 and the absorber 11 move relative to each other, and the coating head 3 continuously discharges droplets from the respective discharge holes 3a, so that the coating liquid is applied to the entire contact surface M2 of the absorber 11. Supplied. Thereby, the contact surface M2 of the absorber 11 is uniformly wetted by the coating liquid. Thereafter, the ejection surface M1 of the coating head 3 is wiped by the absorbent body 11 in a uniform wet state.

  Next, a coating operation (including a discharge stable operation) performed by the above-described coating apparatus 1 will be described. In addition, the control part 9 of the coating device 1 performs a coating process (including a discharge stabilization process) based on various programs.

  As shown in FIG. 9, first, a prewetting process (step S0) is performed, and the absorber 11 is brought into a uniform wet state by the above-described operation. Next, it is determined whether or not the substrate K has been loaded onto the stage 2 (step S1). If it is determined that the substrate K has not been loaded onto the stage 2 (NO in step S1), a predetermined dummy operation is performed. It is determined whether or not the discharge time has elapsed (step S2). If it is determined that the predetermined dummy operation discharge time has not elapsed (NO in step S2), the process returns to step S1.

  If it is determined that the predetermined dummy operation discharge time has elapsed (YES in step S2), it is determined whether or not an additional prewetting time has elapsed (step S3). When it is determined that the additional prewetting time has elapsed (YES in step S3), an additional prewetting for wetting the absorber 11 is performed (step S4), and it is determined that the additional prewetting time has not elapsed. In this case (NO in step S3), dummy ejection is performed (step S5). Thereafter, wiping to wet the ejection surface M1 of the coating head 3 is performed (step S6), and the process returns to step S1. The dummy operation discharge time and the additional prewetting time are stored in advance in the storage unit. For example, the dummy operation discharge time is about 1 minute and the additional prewetting time is about 10 minutes.

  Here, when performing additional prewetting, first, the discharge stabilizing device 6 is moved to the prewetting position where the absorber 11 in the second container H2 faces the coating head 3 by the Y-axis moving mechanism 7, and then, The coating head 3 ejects droplets from the respective ejection holes 3a toward the absorber 11 existing at the pre-wet position. At this time, as described above (see FIGS. 5 to 8), the coating head 3 and the absorber 11 move relative to each other, and the coating head 3 sequentially discharges the droplets sequentially from the respective discharge holes 3a to apply the coating liquid. It supplies to the whole contact surface M2 of the absorber 11. FIG. Thereby, the contact surface M2 of the absorber 11 is uniformly wetted by the coating liquid. The stage 2 is moved to a retreat position that does not interfere with the additional pre-wet by the Y-axis moving mechanism 7 and is on standby.

  In this additional pre-wetting, the discharge amount per droplet of the droplets discharged from each discharge hole 3a and the number of discharges per unit time may be the same as those in step S0, but the absorber 11 is wet. In view of this, the discharge amount per droplet and the number of discharges per unit time may be set smaller than the pre-wet in step S0.

  On the other hand, when performing the dummy discharge, first, the discharge stabilizing device 6 is moved to the dummy discharge position where the first container H1 faces the coating head 3 by the Y-axis moving mechanism 7, and then the first position existing at the dummy discharge position. The coating head 3 ejects droplets from the respective ejection holes 3a toward one container H1. As a result, the coating liquid that has deteriorated in the discharge hole 3a and the deposits (solidified matter, foreign matter, etc.) adhering to the discharge hole 3a are removed, thereby preventing the occurrence of abnormal discharge. Note that the stage 2 is moved to a retracted position by the Y-axis moving mechanism 7 so as not to disturb the dummy discharge and is on standby.

  When wiping is performed, first, the discharge stabilizing device 6 is moved to the wiping position where the absorber 11 in the second container H2 faces the coating head 3 by the Y-axis moving mechanism 7, and then the tank moving mechanism 6b. As a result, the absorber 11 in the second container H2 moves in the Z-axis direction to a contact position where the absorber 11 contacts the ejection surface M1 of the coating head 3, and the contact surface M2 of the absorber 11 contacts the ejection surface M1 of the coating head 3. At this time, the entire surface of the contact surface M2 of the absorber 11 is satisfactorily wetted by the above-described prewetting or additional prewetting. Thereafter, the discharge stabilizing device 6 moves in the Y-axis direction by the Y-axis moving mechanism 7 while bringing the contact surface M2 of the absorber 11 into contact with the discharge surface M1 of the coating head 3, and discharges the coating head 3 by the absorber 11. Wipe the entire surface M1 and wet it uniformly.

  If it is determined in step S1 that the substrate K has been loaded onto the stage 2 (YES in step S1), wiping similar to that described above is performed to wet the ejection surface M1 of the coating head 3 (step S7). It is determined whether or not there is a discharge confirmation (discharge inspection) for confirming the occurrence of a discharge abnormality or not (whether or not the discharge confirmation is performed) (step S8). When it is determined that there is discharge confirmation (YES in step S8), discharge confirmation is performed (step S9). When it is determined that there is no discharge confirmation (NO in step S8), for example, about 1 minute. Dummy discharge is performed (step S10). The presence / absence of discharge confirmation is set in advance by an operator's input operation to the operation unit.

  Then, application | coating is performed (step S11). It is determined whether or not the application for the predetermined number of substrates has been completed (step S12), and if it is determined that the application for the predetermined number of substrates has not been completed (NO in step S12), the process proceeds to step S12. Returning to S1, if it is determined that the application for the predetermined number of substrates has been completed (YES in step S12), the process ends.

  Here, when performing coating, the control unit 9 controls the X-axis moving mechanism 4 and the Y-axis moving mechanism 7 based on the coating information, and moves the coating head 3 to the coating start position facing the coating surface of the substrate K. Let In addition, the discharge stabilizing device 6 is moved to a retreat position where the application is not hindered by the Y-axis moving mechanism 7 and is on standby. Thereafter, the control unit 9 controls the coating head 3 in addition to the X-axis moving mechanism 4 and the Y-axis moving mechanism 7 based on the coating information, and relatively moves the substrate K on the stage 2 and the coating head 3, A droplet is ejected from each ejection hole 3 a of the coating head 3 to apply the coating liquid to the substrate K on the stage 2.

  As described above, according to the first embodiment of the present invention, the entire contact surface M2 of the absorbent body 11 having liquid absorbency is wetted, and the ejection surface M1 of the coating head 3 is wiped with this absorbent body 11. Therefore, it is possible to remove excess coating liquid adhering to the ejection surface 11 and to wet the entire ejection surface M1 of the coating head 3 by bringing the wet contact surface M2 into contact with the ejection surface M1 of the coating head 3. As a result, the entire ejection surface M1 of the coating head 3 can be easily brought into a uniform wet state. As a result, excess coating liquid is removed from the ejection surface M1 of the coating head 3 and a solvent atmosphere is formed in the entire area, so that the coating liquid adhering to the vicinity of the ejection holes 3a of the coating head 3 is dried. Thus, it is prevented that the solidified product is formed, and the coating liquid or the like adhering to a position away from the discharge hole 3a on the discharge surface M1 of the coating head 3 is dried to be a solidified product. It is possible to suppress occurrence of discharge abnormality such as discharge bending due to drying of the applied coating liquid.

  In particular, while moving the coating head 3 and the absorber 11 relative to each other, the liquid droplets are successively discharged from the discharge holes 3a of the coating head 3 and the coating liquid is supplied to the entire contact surface M2 of the absorber 11, Since the contact surface M2 of the absorber 11 can be uniformly wetted by the coating liquid, the entire surface of the ejection surface M1 of the coating head 3 can be uniformly and reliably wetted using the absorber 11. .

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIG.

  The second embodiment of the present invention is basically the same as the first embodiment. Therefore, in the second embodiment, parts different from the first embodiment will be described, and description of the same parts as those described in the second embodiment will be omitted.

  As shown in FIG. 10, the holding member 12 has a built-in liquid channel 21 for flowing the liquid supplied to the absorber 11. The liquid flow path 21 is connected to a supply unit 23 via a pipe 22 such as a tube or a pipe.

  The liquid channel 21 is branched into four channels inside the holding member 12. The four flow paths divide the contact surface M2 of the absorber 11 into four parts, and are individually connected to the centers of the four regions corresponding to the contact surfaces M2. Thereby, since the liquid is uniformly supplied to the entire absorber 11, the entire contact surface M2 is uniformly wetted. The pipe 22 functions as a connection path that connects the liquid flow path 21 of the holding member 12 and the supply unit 23.

  Here, the liquid flow path 21 is branched into four in the holding member 12, but is not limited to this. For example, the liquid flow path 21 may be branched into six, and the number is not limited. Moreover, although the piping 22 is made into one, it is not restricted to this, For example, you may make it provide four. In this case, four liquid flow paths individually communicating with four regions corresponding to the contact surfaces M2 are provided, and four pipes are connected to the liquid flow paths.

  The supply unit 23 includes a storage unit that stores liquid, a pump, a flow rate adjustment valve, and the like. The storage part is formed so as to be detachable, and the type of liquid can be changed by changing the storage part. The supply unit 23 is electrically connected to the control unit 9, and the driving thereof is controlled by the control unit 9, and supplies the liquid to the absorber 11 through the pipe 22 and the liquid flow path 21. As the liquid, for example, a PI (polyimide) liquid, an NMP (N-methyl-2-pyrrolidone) liquid, or the like is used as the same liquid as the coating liquid used by the coating head 3, or a solvent according to the coating liquid. Is used.

  The control unit 9 controls a pump, a flow rate adjusting valve, and the like so as to supply liquid to the absorber 11 for a predetermined time for the entire contact surface M2 of the absorber 11 to get wet. As other controls, for example, a pump, a flow rate adjusting valve, or the like is controlled so that the entire contact surface M2 of the absorber 11 is kept wet, or the wet state of the contact surface M2 of the absorber 11 is detected. A wetting detection unit is provided, and the pump, the flow rate adjusting valve, and the like are controlled so as to maintain the entire wetted contact surface M2 of the absorber 11 in accordance with the detected wet state.

  Here, as the wetting detection unit, for example, a reflection type laser sensor or the like is used. That is, on the contact surface of the absorber 11, the reflectance of the laser light changes according to the wetness (amount of water absorption) (the greater the amount of water absorption, the greater the amount of reflection of the laser light by the liquid, so the reflectance increases). Thus, the output value of the laser sensor when the absorber 11 is in a good wet state is measured and set in advance, and the pre-wet and the additional pre-wet so that the output value by the laser sensor is within the allowable value of the set output value. Should be executed.

  As described above, according to the second embodiment of the present invention, the same effect as in the first embodiment can be obtained. Further, a supply unit 23 for supplying liquid to the absorber 11 is provided in the discharge stabilizing device 6, and the liquid is supplied to the entire contact surface M 2 of the absorber 11 by the supply unit 23, whereby the contact surface M 2 of the absorber 11. Since the absorbent 11 can be used to uniformly wet the entire surface of the ejection surface M1 of the coating head 3.

  In the second embodiment, the necessity of executing an additional prewet for maintaining the contact surface M2 of the absorber 11 in a wet state has been described as being determined using a laser sensor. Similar to the embodiment, the determination may be made based on the elapsed time. In the first embodiment described above, it may be determined using a laser sensor whether or not the additional pre-wetting is necessary.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, some components may be deleted from all the components shown in the above-described embodiment. Furthermore, you may combine the component covering different embodiment suitably. Moreover, in the above-mentioned embodiment, although various numerical values are mentioned, those numerical values are illustrations and are not limited.

  In the above-described embodiment, the single coating head 3 is provided. However, the present invention is not limited to this. For example, the entire width of the substrate K is covered in the X-axis direction orthogonal to the moving direction of the substrate K. A plurality of coating heads 3 may be provided side by side, or a plurality of coating heads 3 may be provided side by side shorter than the entire width of the substrate K in the X-axis direction. When a plurality of coating heads 3 are provided, absorbers 11 corresponding to the number of coating heads 3 may be arranged on the rotation shaft 13 in the X-axis direction, or the coating head 3 and the absorber 11 may be provided on the X-axis. One absorber 11 may be shared by a plurality of coating heads 3 by relative movement in the direction.

  In the above-described embodiment, one Y-axis moving mechanism 7 for individually moving the stage 2 and the discharge stabilizing device 6 in the Y-axis direction is provided. However, the present invention is not limited to this. A moving mechanism may be provided so that the stage 2 and the discharge stabilizing device 6 are individually moved in the Y-axis direction.

  In the above-described embodiment, the absorbent body 11 is provided on one surface of the holding member 12. However, the present invention is not limited to this. For example, the absorbent body is disposed on the entire surface of the holding member 12 aligned with the rotation direction of the rotation shaft 13. 11 may be provided, or the holding member 12 may be formed of an absorbent material and used as the absorbent body 11. In these cases, the new absorber 11 can be used by rotating the rotating shaft 13 such as when the absorber 11 on one surface is soiled or damaged.

DESCRIPTION OF SYMBOLS 1 Application | coating apparatus 2 Stage 3 Application | coating head 3a Ejection hole 6 Ejection stabilization apparatus 7 Moving mechanism 11 Absorber 23 Supply part K Application | coating target object (board | substrate)
M1 discharge surface M2 contact surface

Claims (8)

A stage on which the application object is placed;
An application head that has an ejection surface in which ejection holes for ejecting liquid droplets are formed, and ejects the coating liquid as droplets from the ejection holes toward the application object on the stage;
A moving mechanism for relatively moving the stage and the coating head in the surface direction of the stage;
A liquid-absorbing absorber having a contact surface in contact with the ejection surface of the coating head; wets the entire contact surface of the absorber; and the wet contact surface and the ejection surface of the coating head A discharge stabilizer for bringing the entire surface of the discharge surface of the coating head into contact with the discharge stabilizer,
A coating apparatus comprising:   The coating apparatus according to claim 1, wherein the discharge stabilizing device supplies the coating liquid to the entire contact surface of the absorber by the coating head.   The coating according to claim 1, wherein the discharge stabilizing device includes a supply unit that supplies a liquid to the absorber, and the liquid is supplied to the entire contact surface of the absorber by the supply unit. apparatus.   The ejection stabilization device supplies the coating liquid to the entire contact surface of the absorber by the coating head while relatively moving the coating head and the absorber in the surface direction of the ejection surface. The coating apparatus according to claim 2. A stage on which a coating object is placed and a discharge surface in which a discharge hole for discharging a droplet is formed, and the coating liquid is formed as a droplet from the discharge hole toward the coating object on the stage. An application method for applying the application liquid onto the application object on the stage by using an application head for discharging, and a moving mechanism for relatively moving the stage and the application head in the surface direction of the stage. ,
Using a liquid absorbent absorber having a contact surface in contact with the ejection surface of the coating head, the entire surface of the contact surface of the absorber is wetted, and the wet contact surface and the ejection surface of the coating head A coating method, wherein the entire surface of the ejection surface of the coating head is wetted by contacting the surface.   6. The coating method according to claim 5, wherein the coating liquid is supplied to the entire contact surface of the absorber by the coating head.   The coating method according to claim 5, wherein the liquid is supplied to the entire contact surface of the absorber by a supply unit that supplies the liquid to the absorber.   The said coating liquid is supplied to the whole surface of the said contact surface of the said absorber by the said coating head, moving the said coating head and the said absorber relatively in the surface direction of the said discharge surface. Application method.

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