JP2015134349A - Film formation device, and film formation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately avoid a situation of forming nonuniform thickness of a film, by finding out a situation that a film thickness becomes nonuniform on a substrate just after discharging due to changing of the number of nozzles, by taking into consideration of usefulness of changing of the number of nozzles, when discharging a film liquid on the substrate by using an inkjet head.SOLUTION: A film formation surface 2A of a substrate 2 is partitioned into: rectangular areas 20 of which corners contact an outer peripheral end of the film formation surface 2A, and which is formed of two sides parallel to a relative movement direction between an inkjet head 3 and the substrate 2 and two sides orthogonal to the former two sides; and non-rectangular areas 21 and 22 protruding from the rectangular areas 20. Control is executed in the non-rectangular areas 21 and 22, for changing the number of nozzles 4 for discharging the film liquid with respect to the relative movement direction, and increasing a discharge quantity of the film liquid from the nozzles 4 in response to the increase of the number of nozzles 4 for discharging the film liquid.

Description

  The present invention relates to a technique for forming a film on a semiconductor wafer, a glass substrate, a resin substrate, or the like.

  As well known, as a typical technique for forming a film on a disk-shaped substrate such as a semiconductor wafer, as shown in FIG. 17, a film liquid L is dropped on the center of a substrate (wafer) W, A spin coating method is used in which the wafer W is rotated in the direction of the arrow A0 and the film liquid L is spread by centrifugal force.

  In this spin coating method, since a large amount of the film liquid L is scattered in the direction indicated by the arrow A1 in FIG. 17, 70% to 90% of the film liquid L is discarded on the outer peripheral side of the wafer W. Therefore, in the operation for obtaining a predetermined film thickness on the surface of the wafer W, a large protrusion region B1 for the film liquid L is formed, and the use efficiency (residual film liquid) becomes 10% to 30%, which is large. Waste occurs.

  Further, in this spin coating method, as shown in FIGS. 18A and 18B, an air flow as shown by an arrow A2 is generated as the wafer W rotates in the direction of the arrow A0. It becomes non-uniform and causes uneven coating of the film. Further, as shown in FIG. 19A, in the case where there are convex portions M such as electrodes and parts on the surface of the wafer W, not only uneven coating N1 of the film starting from the convex portions M occurs, As shown in FIG. 19B, there may be a problem that bubbles N2 are generated on the outer peripheral side of the convex portion M.

  Moreover, in this spin coating method, as shown in FIG. 20, the film liquid L spread toward the outer peripheral side of the wafer W by the centrifugal force reaches the back surface Wc side from the outer peripheral end Wb of the wafer W. Invite the situation. Therefore, as shown in FIG. 21, it becomes necessary to wash away the film liquid L adhering to the outer peripheral end Wb and the back surface Wc of the wafer W by using the cleaning liquid by the technique of the back rinse BL and the edge rinse EL. This is not only complicated and troublesome, but also disadvantageous in terms of cost.

  In order to deal with such a problem, in paragraph [0007] of Patent Document 1, as a technique not based on the spin coating method, the nozzle is set while supplying a resist solution from a nozzle discharge hole provided above the wafer. The document describes reciprocating in the X direction and intermittently feeding the wafer in the Y direction. Further, it is also described that a portion other than the circuit formation region of the wafer is covered with a mask in order to prevent the resist solution from adhering to the outer peripheral edge (periphery) and the back surface of the wafer.

  Further, paragraph [0027] of Patent Document 2 is provided with a pair of liquid receiving members that receive the coating liquid falling from the nozzle and prevent the supply of the coating liquid to the outer edge region of the wafer. The distance between the liquid receiving members is variable in the X direction, and the tip portions of the pair of liquid receiving members can be adjusted so as to be positioned slightly inside the outer edge of the wafer regardless of the position in the Y direction of the wafer. Have been described.

  Further, in paragraph [0050] and FIG. 12 of Patent Document 2, a large number of discharge ports are arranged in a line over the length corresponding to the diameter of the wafer in the coating solution nozzle, and the coating solution is discharged from the discharge port. In addition, it is described that the coating solution is scanned and applied by translational movement from one end side to the other end side of the wafer. In this case as well, a pair of liquid receiving members that receive the coating liquid falling from a large number of discharge ports and prevent the supply of the coating liquid to the outer edge region of the wafer should be provided.

JP 2001-237179 A International Publication WO2005 / 034228A1

  By the way, in any of the configurations disclosed in Patent Documents 1 and 2 described above, in order to prevent the film liquid dropped from the nozzle (ejection port) from reaching the back surface from the outer peripheral end of the wafer, a mask or a liquid receiving member is used. Is required, and the structure of the device around the wafer is complicated. Moreover, even if a mask or a liquid receiving member is provided, these members cannot withstand long-term use, so that a problem of durability also arises.

  In addition to the film liquid that falls from the nozzle (discharge port) due to the film liquid dripping from the tip surface (inner peripheral end surface) of the mask or liquid receiving member, there is film liquid that falls around the required position of the wafer. Will do. When such a situation occurs, it becomes difficult to drop the film solution to the exact required position, and not only can the region where the film is actually formed on the wafer be distorted, but also the film thickness obtained on the wafer. The uniformity of the is inhibited.

  In addition, there may be a request to form a film similar to the above on a rectangular or polygonal substrate, but in such a case, how to deal with the problems described above There is a problem of what to do.

  In order to avoid the above problems, it is conceivable to discharge a film liquid onto a substrate using an appropriate number of nozzles from a plurality of nozzles in an inkjet head such as a piezo method. In this case, this type of inkjet head has a phenomenon that the film thickness immediately after ejection on the substrate becomes non-uniform when the number of nozzles ejecting the film liquid changes.

  However, in the past, regarding the point where such a phenomenon occurs disadvantageously, and the point of trying to eliminate the situation when such a phenomenon occurs, It was the actual situation that these two points were left unattended even though they were not even focused on these two points.

  In the present invention, in view of the above circumstances, when a film liquid is discharged onto a substrate using an ink jet head, the film thickness on the substrate immediately after discharge becomes non-uniform due to a change in the number of nozzles. Finding in consideration of the benefits, and to avoid that situation accurately.

  First, prior to the description of the present invention, technical means having the basic configuration of the present invention will be described below. That is, this technical means is such that a discharge surface of an inkjet head in which a plurality of nozzles for discharging a film liquid are arranged in the width direction and a film formation surface of a substrate on which the film liquid is discharged from the nozzles are opposed to each other. The film liquid is discharged from the nozzle onto the film forming surface of the substrate while the ink jet head and the substrate are not rotated, and both are relatively moved in a direction orthogonal to the width direction. In the film forming apparatus, the arrangement width length of the nozzles of the inkjet head is set to be equal to or greater than the maximum length in the width direction of the film forming surface of the substrate when the substrate relatively moves, and the relative movement of the two is performed. In order to prevent the film liquid from adhering from the outer peripheral edge of the substrate toward the back surface side until the completion of the process, the discharged film liquid is attached to the film forming surface and the outer peripheral edge of the substrate. To stop at the boundary between, which is constituted of the number of nozzles for discharging film liquid in the plurality of nozzles so as to variably control.

  According to such a configuration, the number of nozzles for discharging the film liquid is variably controlled while the inkjet head and the substrate are relatively moved, regardless of the shape and posture of the substrate. This prevents the film liquid from adhering to the boundary between the film forming surface and the outer peripheral edge of the substrate from the head portion to the rear edge portion of the substrate, and avoids the problem that the film liquid reaches the outer peripheral edge and the back surface. The Therefore, unlike the prior art, no mask or liquid receiving member is required, the structure of the apparatus around the substrate is simplified, and no dripping of the film liquid from the mask or liquid receiving member is eliminated. Can be accurately discharged, and the accuracy of the film thickness on the substrate can be secured. In this case, in order to variably control the number of nozzles for discharging the film liquid, BMP data determined from the relative movement position of the inkjet head and the substrate and the position of the film formation surface on the substrate is created, and the BMP data The plurality of nozzles of the inkjet head may be controlled based on the above.

  In the above configuration, the aspect in which the substrate moves relative to the inkjet head is a rectangular substrate having two sides parallel to the relative movement direction and two sides orthogonal to the direction. It is advantageous that this is not the case.

  In this way, in the case where the substrate has the above-described rectangular shape, if the number of nozzles for discharging the film liquid is determined in advance, whether or not the film liquid is discharged from all of these nozzles, that is, It is only necessary to perform variable control of whether the number of nozzles for discharging the film liquid is zero or constant. On the other hand, when the substrate is not in the form of a rectangle as described above, it is necessary to precisely change the number of nozzles for discharging the film liquid in the non-rectangular area protruding from the rectangular area. However, according to the above configuration, it is possible to appropriately respond to such a request.

  Examples of such a substrate include a substrate having a disc shape and a substrate having a square plate shape such as a rectangle, a triangle, and other polygons. In the case of a rectangular plate-shaped substrate, it is advantageous when the substrate is inclined with respect to the relative movement direction.

  In the above configuration, it is preferable that the film thickness after drying of the film solution discharged toward the film forming surface of the substrate can be controlled to have a lower limit of 300 nm and an upper limit of 30 μm or more.

  In this way, a very thin film having a thickness of about 300 nm and a very thick film having a thickness of 30 μm or more can be accurately formed on the substrate. In addition, when forming an extremely thick film of 20 μm or more or 30 μm or more, it is performed by overcoating without limitation on the number of times. In this case, the upper limit value is set to 100 μm, for example.

  In the above configuration, the discharge amount of the film liquid discharged toward the film forming surface of the substrate to become a usable film after drying is 95% to 100% (preferably 100%) of the total discharge amount. be able to.

  In this way, an ink jet apparatus such as an ink jet printer, that is, an ink jet head is effectively used, and waste of the film liquid can be reduced as much as possible.

  In the above configuration, relative to a rectangular region having two sides parallel to the relative moving direction and two sides orthogonal to the relative movement direction with a corner portion in contact with the outer peripheral edge of the substrate. Regardless of the difference in the moving position, the relative moving position is applied to a non-rectangular area that discharges the film liquid from a certain number of nozzles and protrudes from the rectangular area on the film forming surface of the substrate. It is preferable to control so that the film liquid is discharged from a different number of nozzles according to the difference.

  This simplifies the nozzle control for the rectangular area of the substrate, and therefore efficiently simplifies the nozzle control for the entire substrate.

  In this case, it is preferable that the non-rectangular region is divided into a plurality of partial regions in the relative movement direction, and the ejection amount of the film liquid from each nozzle is variably controlled according to the plurality of partial regions. .

  In this way, since it is sufficient to perform the control with the partial region as a unit, it is possible to ensure the accuracy of the control while avoiding the complexity of the control.

  In the above configuration, the inkjet head is preferably a parallel inkjet head in which a plurality of individual inkjet heads are arranged in a staggered manner in the width direction.

  In this way, since it is possible to cope with an increase in the size of the substrate, it can be widely used from a small substrate to a large substrate.

  In the above configuration, in the streak region connected to the inner peripheral side of the boundary between the film forming surface of the substrate and the outer peripheral end, the discharge amount of the film liquid gradually increases toward the inner peripheral side, In a region continuous from the region to the inner peripheral side, it is preferable to control the discharge amount to be the same as the increased maximum discharge amount of the film liquid.

  In this way, when the film liquid is formed with a uniform discharge amount on the film forming surface of the substrate, that is, when the liquid surface height of the film liquid is made uniform over the entire film forming surface of the substrate. After the film solution is dried, the film thickness gradually increases as the streak region connected to the inner peripheral side of the boundary moves to the outer peripheral side. Therefore, when the film liquid is discharged, if the line-shaped region is controlled so that the discharge amount of the film liquid gradually increases as it moves to the inner peripheral side, it is uniform on the substrate after drying. A film thickness can be obtained.

  In this case, the streak region is divided into a plurality of partial streak regions from the inner peripheral side to the outer peripheral side, and the discharge amount of the film liquid from each nozzle is variable according to the plurality of partial streak regions. It is preferable to control.

  In this way, since it is only necessary to control the partial streak region as a unit, it is possible to ensure the accuracy of the control while avoiding the complexity of the control.

  In the above configuration, a plurality of closed regions in which a film is formed on the film forming surface by controlling discharge and non-discharge of the film liquid to the plurality of nozzles during the relative movement, and a film A region in which no film is formed can be created, and during the relative movement, a film is not formed on the film formation surface by controlling the discharge and non-discharge of the film liquid to the plurality of nozzles. It is also possible to create a plurality of closed regions and regions where a membrane is formed.

  According to such a configuration, it is possible to create a film formation state that is impossible with the conventional spin coating method or a method using a nozzle, and is particularly effective when the substrate has a disk shape.

  In another technical means, an ejection surface of an inkjet head in which a plurality of nozzles that eject film liquid are arranged in the width direction is opposed to a film formation surface of a substrate from which the film liquid is ejected from the nozzle. The film liquid is discharged from the nozzle onto the film forming surface of the substrate while the inkjet head and the substrate are not rotated, and both of them are relatively moved in a direction perpendicular to the width direction. In the film forming apparatus, the substrate is moved relative to the inkjet head in a rectangular shape including two sides parallel to the relative movement direction and two sides orthogonal to the direction. The arrangement width length of the nozzles of the ink jet head is not an aspect to be a substrate, but is set to be equal to or larger than the maximum length in the width direction of the film forming surface of the substrate when the substrate relatively moves. Until completing a pair movement, the number of nozzles for discharging film liquid in the plurality of nozzles is to variably control.

  According to such a configuration, it is possible to obtain substantially the same operational effects as the above technical means. However, in this case, the relationship between the film formation surface on the substrate and the outer peripheral edge of the substrate is not subject to strict restrictions as in the above technical means.

  Further, another technical means is that an ejection surface of an inkjet head in which a plurality of nozzles that eject film liquid are arranged in the width direction is opposed to a film formation surface of a substrate from which the film liquid is ejected from the nozzle. The film liquid is discharged from the nozzle onto the film forming surface of the substrate while the inkjet head and the substrate are not rotated, and both of them are relatively moved in a direction perpendicular to the width direction. In the film forming apparatus, the discharge amount of the film liquid gradually increases toward the inner peripheral side from the outer peripheral end of the film forming surface of the substrate to the inner peripheral side. In the region connected to the circumferential side, the discharge amount is controlled to be the same as the increased maximum discharge amount of the film liquid.

  According to such a configuration, the following effects can be obtained. That is, when the film liquid is formed with a uniform discharge amount on the film forming surface of the substrate, that is, when the liquid surface height of the film liquid is made uniform over the entire area of the film forming surface of the substrate, After drying, the film thickness gradually increases as the streaky region extending from the outer peripheral edge of the film forming surface to the inner peripheral side moves to the outer peripheral side. Therefore, when the film liquid is discharged, if the line-shaped region is controlled so that the discharge amount of the film liquid gradually increases as it moves to the inner peripheral side, it is uniform on the substrate after drying. A film thickness can be obtained.

  In the above configuration, the substrate may be a semiconductor wafer, a glass substrate, or a resin substrate.

  Based on the technical means as described above, an apparatus according to the present invention, which was created to solve the above-described problems, includes an ejection surface of an inkjet head in which a plurality of nozzles that eject film liquid are arranged in the width direction, While facing the film formation surface of the substrate from which the film liquid is discharged from the nozzle, the inkjet head and the substrate are moved in a non-rotating state, while relatively moving both in the direction perpendicular to the width direction, In the film forming apparatus configured to discharge the film liquid from the nozzle onto the film forming surface of the substrate, the arrangement width length of the nozzles of the ink jet head is set so that the substrate moves when the substrate relatively moves. More than the maximum length in the width direction of the film forming surface, the film forming surface of the substrate is perpendicular to this direction with two sides that are in contact with the peripheral edge of the film forming surface and parallel to the relative moving direction. two And a non-rectangular area protruding from the rectangular area. In the non-rectangular area, the number of nozzles that discharge the film liquid is changed in the relative movement direction. At the same time, it is characterized in that control is performed to increase the discharge amount of the film liquid from the nozzle as the number of nozzles discharging the film liquid increases.

  According to such a configuration, in the non-rectangular region on the film forming surface of the substrate, it is effective to change the number of nozzles for discharging the film liquid with respect to the relative movement direction. In addition, the phenomenon that the film thickness immediately after ejection in the non-rectangular region of the film formation surface when the number of nozzles for ejecting the film liquid is varied is accurately avoided.

  In this case, the non-rectangular region is divided into a plurality of partial regions in the relative movement direction, and the number of nozzles and the discharge amount of the film liquid from the nozzles according to the difference of the partial regions. It is preferable to configure so that different controls are performed.

  In the configuration of the apparatus according to the present invention described above, in the rectangular region, the number of nozzles for discharging the film liquid and the discharge amount of the film liquid from the nozzles are made constant regardless of the relative movement position. It is preferable that the control is performed.

  In the configuration of the apparatus according to the present invention, the rectangular area includes a central rectangular area where four corner portions are in contact with an outer peripheral end of the film forming surface, and the center with respect to a direction orthogonal to the relative moving direction. The rectangular region is divided into a side rectangular region that is disposed on both sides of the rectangular region and has two corner portions in contact with an outer peripheral end of the film forming surface, and the relative moving position in each of the central rectangular region and the side rectangular region. It is preferable that the control is performed so that the number of nozzles for discharging the film liquid and the discharge amount of the film liquid from the nozzles are made constant regardless of the difference.

  Further, the method according to the present invention, which was created to solve the above-described problems, includes a discharge surface of an inkjet head in which a plurality of nozzles for discharging a film liquid are arranged in the width direction, and a film liquid is discharged from the nozzle. With the film formation surface of the substrate facing each other, the ink jet head and the substrate are not rotated, and the two are relatively moved in a direction perpendicular to the width direction from the nozzle to the film formation surface of the substrate. In the film forming method for discharging the film liquid, the nozzle array width length of the inkjet head is set to be equal to or greater than the maximum length in the width direction of the film forming surface of the substrate when the substrate relatively moves, A film forming surface of the substrate, a rectangular region having a corner portion in contact with an outer peripheral edge of the film forming surface and having two sides parallel to the relative movement direction and two sides orthogonal to the direction; and the rectangular region Food In the non-rectangular area, the number of nozzles for discharging the film liquid is changed with respect to the relative movement direction, and the number of nozzles for discharging the film liquid is large. Accordingly, the control is performed to increase the discharge amount of the film liquid from the nozzle.

  According to such a method, substantially the same operational effects as those of the above-described apparatus according to the present invention can be obtained.

  As described above, according to the present invention, when the film liquid is discharged onto the substrate using the ink jet head, the film thickness on the substrate immediately after discharge becomes non-uniform due to the change in the number of nozzles. Is found in consideration of the benefits, and the situation is avoided accurately.

1 is a perspective view showing a schematic configuration of a film forming apparatus according to a first embodiment of the present invention. It is the schematic which shows an example of the arrangement state of the nozzle in the lower surface of the inkjet head which is a component of the film forming apparatus which concerns on 1st Embodiment of this invention. FIG. 3A is a schematic front view showing a first example of a nozzle film liquid discharge method which is a component of the film forming apparatus according to the first embodiment of the present invention, and FIG. It is a schematic front view which shows the 2nd example of the film | membrane liquid discharge system of the nozzle which is a component of the film forming apparatus which concerns on 1st Embodiment of invention, FIG.3 (c) concerns on 1st Embodiment of this invention. It is a schematic front view which shows the 3rd example of the film | membrane liquid discharge system of the nozzle which is a component of a film formation apparatus. It is a schematic plan view for demonstrating the 1st example of the discharge state of the film | membrane liquid with respect to the film formation surface on the board | substrate which concerns on 1st Embodiment of this invention. FIG. 5A is a schematic plan view for explaining the problem of the discharge state of the film liquid on a part of the film formation surface on the substrate according to the first embodiment of the present invention, and FIG. These are FF sectional views of Drawing 5 (a). FIG. 6A is a schematic plan view for explaining a discharge state of the film liquid to a part of the film forming surface on the substrate according to the first embodiment of the present invention, and FIG. It is GG sectional drawing of 6 (a). FIG. 7A is an enlarged longitudinal sectional view showing a problem of the outer peripheral portion immediately after the film is formed on the substrate according to the first embodiment of the present invention, and FIG. It is an enlarged longitudinal cross-sectional view which shows the problem of the outer peripheral side part after drying after the film | membrane was formed on the board | substrate concerning 1st Embodiment of this. FIG. 8A is an enlarged longitudinal sectional view showing an outer peripheral side portion immediately after the film is formed on the substrate according to the first embodiment of the present invention, and FIG. 8B is the first embodiment of the present invention. It is an expanded longitudinal cross-sectional view which shows the outer peripheral side part after drying after the film | membrane was formed on the board | substrate which concerns on embodiment. It is a schematic plan view for demonstrating the 2nd example of the discharge state of the film | membrane liquid with respect to the film formation surface on the board | substrate which concerns on 1st Embodiment of this invention. It is a partial expansion schematic plan view for demonstrating the 2nd example of the discharge state of the film | membrane liquid with respect to the film formation surface on the board | substrate which concerns on 1st Embodiment of this invention. It is a partial expansion schematic plan view for demonstrating the discharge state of the film | membrane liquid with respect to the film formation surface on the board | substrate which concerns on 2nd Embodiment of this invention. It is a partial expansion schematic plan view for demonstrating the discharge state of the film | membrane liquid with respect to the film formation surface on the board | substrate which concerns on 3rd Embodiment of this invention. It is a schematic longitudinal cross-sectional side view which shows the formation state of the film | membrane on the board | substrate concerning 4th Embodiment of this invention. It is a schematic longitudinal cross-sectional side view which shows the formation state of the film | membrane on the board | substrate which concerns on 5th Embodiment of this invention. FIG. 15A is a schematic plan view showing a first example of a film formation state on a substrate according to the sixth embodiment of the present invention, and FIG. 15B is a diagram according to the sixth embodiment of the present invention. It is a schematic plan view which shows the 2nd example of the film formation state on a board | substrate. FIG. 16A is a schematic plan view showing a first example of a film formation state on a substrate according to the seventh embodiment of the present invention, and FIG. 16B according to the seventh embodiment of the present invention. It is a schematic plan view which shows the 2nd example of the film formation state on a board | substrate. It is a schematic perspective view for demonstrating the conventional problem. FIG. 18A is a schematic plan view for explaining conventional problems, and FIG. 18B is a schematic front view for explaining conventional problems. FIG. 19A is a schematic plan view for explaining conventional problems, and FIG. 19B is a schematic front view for explaining conventional problems. It is a schematic longitudinal front view for demonstrating the conventional problem. It is a schematic longitudinal front view for demonstrating the conventional problem.

  Hereinafter, a film forming apparatus and a film forming method according to embodiments of the present invention will be described with reference to the drawings.

  First, a film forming apparatus and a film forming method according to a first embodiment of the present invention will be described. As shown in FIG. 1, in the film forming apparatus 1, a disk-shaped substrate 2 made of a semiconductor wafer is conveyed in the direction of arrow A, and a piezo-type inkjet head 3 is fixed above the conveyance path. is set up. The inkjet head 3 is a side-by-side inkjet head in which a plurality (five in the illustrated example) of individual inkjet heads 3 a are arranged in a staggered manner in the width direction B perpendicular to the transport direction A. A plurality of nozzles 4 are arranged in the width direction B at the same nozzle pitch 4P on the lower surface (ejection surface) of each individual inkjet head 3a in the inkjet head 3. Therefore, in the ink jet head 3 as a whole, a large number of nozzles 4 are arranged in the width direction B at a constant nozzle pitch 4P. Data indicating the positions of all the nozzles 4 is stored in the storage unit 5 of the inkjet head 3.

  Regarding the ejection of the film liquid onto the surface of the substrate 2, BMP data (bitmap data) determined according to the position in the transport direction A of the substrate 2 and the position of the film forming surface 2A on the surface of the substrate 2 is stored in the storage unit. 5 is stored. This BMP data indicates the number of nozzles 4 for discharging the film liquid to each nozzle 4 of the inkjet head 3, the discharge amount of the film liquid from each nozzle 4, and whether or not the film liquid is discharged from each nozzle 4. Can be specified. Therefore, the discharge pitch of the film liquid of each nozzle 4 can be arbitrarily specified. The substrate 2 is transported at a speed of 2 mm / sec to 100 mm / sec, preferably 10 mm / sec to 50 mm / sec. The transport speed of the substrate 2 depends on the amount of film liquid discharged from the nozzle 4 and the discharge speed. The frequency is appropriately set in consideration of the arrangement state of the nozzles 4 and the like.

  As shown enlarged in FIG. 1 by reference C, the coating state of the film liquid on the film forming surface 2A of the substrate 2 per unit area is the case where the film liquid 6 is discharged from all the nozzles 4 of the ink jet head 3 (100 %), In the relationship between the nozzle pitch 4P and the discharge pitch Ap in the transport direction, all the film liquids 6 (lines forming the circle shape shown in the figure) are overlapped without a gap.

  FIG. 2 shows an example of the arrangement state of the nozzles 4 on the lower surface of the inkjet head 3. Two line-type inkjet nozzles 3 b are attached in parallel to the lower surface of each individual inkjet head 3 a in the inkjet head 3. The position of each nozzle 4 of one line-type inkjet nozzle 3b and the position of each nozzle 4 of the other line-type inkjet nozzle 3b are shifted in the width direction B by a half pitch of the nozzle pitch 4P. Accordingly, the substantial nozzle array pitch of the inkjet head 3 as a whole is ½ of the nozzle pitch 4P of the individual line-type inkjet nozzles 3b. Note that the number of line-type inkjet nozzles 3b and the arrangement state of the nozzles 4 are not limited thereto.

  Here, a discharge method of the film liquid discharged from the inkjet head 3 will be described. FIG. 3A shows a film having a predetermined discharge amount when the discharge data corresponding to one nozzle 4 is turned on once on the BMP data of the image data in a method called a binary mode. In this mode, only one drop of the liquid 6 is discharged. FIG. 3B is a method called a multi-drop mode, and a number from 1 to 7 (3 in this example) is added to the ejection data corresponding to one nozzle 4 on the BMP data of the image data. In this case, it is a mode in which three drops of the predetermined amount of film liquid 6 are discharged continuously by turning on once. FIG. 3C shows a method called a DPN mode, in which the discharge amount data is input to the discharge data corresponding to one nozzle 4 on the BMP data of the image data, and is turned on only once. In this mode, the film liquid 6 having the input discharge amount is discharged. Any of these methods can be adopted in the present invention, but in this embodiment, the binary mode method shown in FIG. 3A is adopted. The reason is that the binary mode method does not require complicated electric control compared to the other two methods.

  FIG. 4 illustrates a mode in which the film liquid 6 is ejected from the inkjet head 3 to the film forming surface 2A on the surface of the substrate 2. Since the film forming surface 2A of the substrate 2 is circular, its outline does not coincide with the transport direction A and does not coincide with the width direction B, and the arrangement length of the nozzles of the inkjet head 3 in the width direction is the film of the substrate 2 It is longer than the maximum length in the width direction of the formation surface 2A (the diameter D1 of the film formation surface 2A). Then, the entire circular area as the film forming surface 2A has three rectangular areas 20 that are present in the center in the width direction B and whose corner portions are in contact with the circular outline, two left and right partial circular areas 21, and six upper and lower parts. It is divided into a circular region 22. In this case, the rectangular area 20 is disposed on both sides of the central rectangular area 20 in which the four corner portions are in contact with the circular contour that is the outer peripheral end of the film forming surface 2A and the central rectangular area 2 with respect to the direction orthogonal to the transport direction A. And a side rectangular region 20 in which two corners are in contact with the circular contour of the film forming surface 2A. In the three rectangular regions 20, the number of nozzles 4 that discharge the film liquid in the inkjet head 3 is a fixed number regardless of the movement position in the transport direction A. Specifically, the three individual inkjets The film 3 is discharged from the fixed number of nozzles 4 (all nozzles 4 in this embodiment) by the head 3a. On the other hand, in the eight partial circular regions 21 and 22, the number of nozzles 4 for discharging the film liquid in the inkjet head 3 changes according to the difference in the movement position in the transport direction A. As a result, the discharge state of the film liquid follows a circular outline, and as a result, the film liquid is discharged so as to be an accurate circle over the entire area of the circular film formation surface 2A. The control as described above is performed by the control means 7 (see FIG. 1) based on the BMP data stored in the storage means 5.

  In this case, of the eight partial circular regions 21 and 22, the two left and right partial circular regions 21 are each divided into a plurality (12 in the example) of regions a to l with respect to the transport direction A. Depending on the difference, the discharge amount of the film liquid from each nozzle 4 changes. Further, the upper and lower four partial circular areas 22 excluding the upper and lower areas in the center in the width direction B are each divided into a plurality (6 in the illustrated example) of areas a to f with respect to the transport direction A. Depending on the difference, the discharge amount of the film liquid from each nozzle 4 changes. Each of the upper and lower partial circular regions 22 at the center in the width direction B is also divided into a plurality of regions with respect to the transport direction A, and the film liquid from the individual nozzles 4 is divided according to their difference. The discharge amount may be changed, but such a thing may not be performed. The control as described above is performed by the control means 7 based on the BMP data stored in the storage means 5.

  Here, as a characteristic of the inkjet head 3, it is well known that the film thickness immediately after ejection becomes non-uniform when the number of nozzles 4 ejecting the film liquid changes. Such a phenomenon is called a crosstalk phenomenon. Specifically, when the number of nozzles 4 that discharge the film liquid is small, the discharge amount of the film liquid from each nozzle 4 increases, and when the number of nozzles 4 that discharge the film liquid is large, The amount of film liquid discharged from each nozzle 4 is reduced. Therefore, if only the number of nozzles 4 for discharging the film liquid is changed in the above-described eight (or six) partial circular regions 21 and 22, the film thickness immediately after the discharge becomes non-uniform. Specifically, in the partial circular region 21 shown in FIG. 5A, the number of nozzles 4 that discharge the film liquid gradually decreases as the region moves from the central portion in the vertical direction to both ends. Therefore, the film 8 immediately after being discharged onto the film forming surface 2A on the surface of the substrate 2 has a thin film thickness at the center in the vertical direction as shown in FIG. Gradually, the film thickness increases. Therefore, it is only necessary to gradually reduce the amount of film liquid discharged from the nozzle 4 as it moves from the vertical center to the vertical ends. In this embodiment, as shown in FIG. 6A (that is, as shown in FIG. 4), the partial circular region 21 is divided into a plurality of (for example, 12) regions a to l with respect to the transport direction A, The discharge amount of the film liquid from each nozzle 4 is increased in the regions f and g in the central portion in the vertical direction, and the discharge amount is decreased as the region moves to the regions on both ends. As a result, as shown in FIG. 6B, the film 8 immediately after being discharged onto the film forming surface 2A on the surface of the substrate 2 has a uniform film thickness over the entire area a to l in the vertical direction. In order to make the film thickness uniform in this way, the discharge amount of the film liquid from the individual nozzles 4 for the above-mentioned 12 regions is measured in advance with a weigh scale and stored in the storage means 5. Based on the obtained data, the control means 7 may automatically correct the discharge amount of the film liquid in the partial circular region 21 to be uniform. Then, by performing the same for the other partial circular regions 21 and 22, the film thickness immediately after ejection is uniform over the entire region of the circular film forming surface 2A. The control as described above is performed by the control means 7 based on the BMP data stored in the storage means 5. In the rectangular region 20, since the number of the nozzles 4 that discharge the film liquid is a fixed number regardless of the movement position in the transport direction A as described above, the discharge amount of the film liquid from the nozzles 4 is also large. The amount is constant regardless of the movement position.

  FIG. 7A shows a coating state of the film 8 having a uniform film thickness immediately after ejection on the substrate 2. This application state prevents the film liquid from adhering from the curved outer peripheral end 2b of the substrate 2 toward the back surface 2c, and the boundary 2d between the curved outer peripheral end 2b and the planar film forming surface 2A. The film 8 (film liquid) is prevented from adhering. Therefore, the outer peripheral end 8b of the film 8 is located at or near the boundary 2d between the curved outer peripheral end 2b of the substrate 2 and the planar film forming surface 2A. In addition, when the outer peripheral end of the substrate 2 is curved and does not largely protrude to the outer peripheral side as shown in the drawing, the portion that can be regarded as the outer peripheral end of the substrate 2 and the planar film forming surface 2A The boundary is the position of the outer peripheral end 8 b of the film 8. In other words, the outer peripheral end 8 b of the film 8 does not have to reach the back surface side portion 2 e in the outer peripheral end 2 b of the substrate 2.

  When the film 8 is dried under such a state, as shown in FIG. 7B, a narrow streak region 23 existing on the inner peripheral side from the outer peripheral end 8b of the dried film 8A. Only the bulge is raised, and the central region is relatively thin and uniform. Such a phenomenon is generally called a coffee ring phenomenon. Therefore, in this embodiment, as shown in FIG. 8A, the streak region 23 on the inner peripheral side of the outer peripheral end 8b of the film 8 immediately after ejection is shifted from the inner peripheral side to the outer peripheral side. Thus, the film liquid is discharged from the predetermined nozzle 4 so that the film thickness gradually decreases. In this case, the surface (upper surface) 8c of the film 8 in the streak region 23 immediately after the discharge of the film liquid is inclined downward from the inner peripheral side toward the outer peripheral side and is curved slightly concavely. When the film 8 is dried from such a state, as shown in FIG. 8B, the film thickness becomes uniform over the entire region from the outer peripheral end 8Ab to the center of the film 8A. Specific control for this is performed as follows.

  That is, as shown in FIG. 9, the circular film-forming surface 2A on the substrate 2 is divided into a plurality of (12 in the illustrated example) fan-shaped regions 24 in the circumferential direction at an equal angle, and the outermost streaks are further formed. The region 23 is divided into a plurality (six in the illustrated example) of partial arc-shaped regions a to f in the radial direction. Then, for each of the twelve fan-shaped regions 24, the discharge amount of the film liquid from the nozzle 4 is corrected for each of the six partial arc-shaped regions a to f. As a result, as shown in FIG. In addition, the film thickness of the dried film 8A is made uniform. The reason why the film liquid is divided into 12 parts in the circumferential direction without correcting the discharge amount of the film liquid from the nozzle 4 all over the circumference of the streak region 23 is to ensure easy control and accuracy. The correction data individually corrected for the sector area 24 divided into 12 is stored in the storage means 5. In addition, although the notch part 2B is formed in the upper end of the figure, as shown in FIG. 10, this notch part 2B is divided into a plurality of (6 in the illustrated example) in the radial direction as one partition part. If the discharge amount is corrected in the same manner as described above for the V-type regions a to f, the thickness of the notch portion 2B is uniform after drying. can get. Even when an orientation flat having a shape other than the notch portion 2B is provided, the same thing is performed on the orientation flat. The control as described above is performed by the control means 7 based on the BMP data stored in the storage means 5.

  FIG. 11 is a schematic plan view of the film forming apparatus 1 according to the second embodiment of the present invention, in which the film liquid 6 is discharged from the inkjet head 3 onto the film forming surface 2A on the surface of the substrate 2. Illustrated. The film forming apparatus 1 according to the second embodiment is greatly different from that according to the first embodiment described above, in that the substrate 2 is a rectangular glass substrate or a resin substrate, and is in the transport direction A. It is a point with an inclined posture. Therefore, as shown in FIG. 11, the outline of the substrate 2 does not coincide with the transport direction A and does not coincide with the width direction B, and the arrangement length of the nozzles of the inkjet head 3 in the width direction is the film formation surface of the substrate 2. It is longer than the maximum length L1 in the width direction of 2A. In this case, the entire rectangular area that is the film forming surface 2A is composed of three rectangular areas 25 that are present at the center in the width direction B and whose corners are in contact with the rectangular outline, two non-rectangular areas 26 on the left and right sides, It is divided into a non-rectangular area 27. In the three rectangular regions 25, the number of nozzles 4 that discharge the film liquid in the inkjet head 3 is a fixed number regardless of the movement position in the transport direction A. Specifically, the three individual inkjets The film 3 is discharged from the fixed number of nozzles 4 (all nozzles 4 in this embodiment) by the head 3a. On the other hand, in the eight non-rectangular regions 26 and 27, the number of nozzles 4 that eject the film liquid in the inkjet head 3 changes according to the difference in the movement position in the transport direction A. As a result, the discharge state of the film liquid follows the rectangular outline of the inclined posture, and as a result, the film liquid is discharged to the entire region of the rectangular film forming surface 2A in the inclined posture. The control as described above is performed by the control means 7 based on the BMP data stored in the storage means 5. In this case, each of the two left and right non-rectangular regions 26 is divided into a plurality (four in the illustrated example) of regions a to d with respect to the transport direction A, and individual nozzles are determined according to the difference between these regions. The discharge amount of the film liquid from 4 changes. Each of the upper and lower eight non-rectangular regions 27 is divided into a plurality (six (in some cases, five)) regions a to f (some are a to e) in the transport direction A, The discharge amount of the film liquid from each nozzle 4 changes according to the difference in these regions, and control for making the film thickness non-uniformity of the film 8 immediately after the discharge onto the substrate 2 uniform. Is substantially the same control as described above with reference to FIGS. 6A and 6B, and in order to make the film 8A non-uniform in thickness after drying. 8 is substantially the same as that described with reference to Fig. 8 (a) and Fig. 8 (b), and formation of the outer peripheral end 2b of the substrate 2 and the films 8 and 8A. The relationship with the position is substantially the same as that described with reference to FIGS.

  FIG. 12 is a schematic plan view of the film forming apparatus 1 according to the third embodiment of the present invention, in which the film liquid 6 is discharged from the inkjet head 3 onto the film forming surface 2A on the surface of the substrate 2. Illustrated. The film forming apparatus 1 according to the third embodiment is greatly different from that according to the second embodiment described above in that the substrate 2 made of a rectangular glass substrate or a resin substrate is not inclined with respect to the transport direction A. It is a point that is regarded as a posture. The arrangement length of the nozzles of the inkjet head 3 in the width direction is longer than the maximum length L2 in the width direction of the film formation surface 2A of the substrate 2 (the length of one side of the film formation surface 2A). Therefore, the number of nozzles 4 for discharging the film liquid in the inkjet head 3 changes with respect to the film forming surface 2A on the substrate 2 when the lower side of the rectangular film forming surface 2A passes through. There are a case of changing to a number and a case of changing from a certain number to zero when passing the upper side of the film forming surface 2A. However, in the case of such a change, strict control is necessary for the positional relationship between the outer peripheral end 2b of the substrate 2 and the film forming surface 2A. Further, in this embodiment, the three rectangular regions 28 in the central portion in the width direction B are discharged from the fixed number of nozzles 4 (all nozzles 4 in this embodiment) by the three individual inkjet heads 3. Is discharged. On the other hand, in the left and right two-part rectangular regions 29, the film liquid is discharged from a smaller number of nozzles 4 than the predetermined number. Therefore, in these two partial rectangular areas 29, the discharge amount of the film liquid from each nozzle 4 is reduced as compared with the three rectangular areas 28 in the central portion. Note that the control for making the non-uniformity of the film thickness of the film 8A after drying substantially the same control as that described with reference to FIGS. 8 (a) and 8 (b). Is called. Further, the relationship between the outer peripheral end 2b of the substrate 2 and the positions where the films 8 and 8A are formed is substantially the same as that described with reference to FIGS.

  FIG. 13 illustrates a film forming apparatus 1 according to the fourth embodiment of the present invention. The film forming apparatus 1 according to the fourth embodiment is different from those according to the first, second, and third embodiments described above in that the substrate 2 has a circular or inclined rectangular or non-inclined attitude. When there are a plurality of convex portions 9 such as electrode films and parts on the film forming surface 2A, the film 8A after drying is controlled by electrically variably controlling the discharge amount of the film liquid from the required nozzle 4 of the ink jet head 3. The film thickness is uniform. Further, in this case, bubbles are not generated. Other controls are substantially the same as those in the first, second, and third embodiments described above.

  FIG. 14 illustrates a film forming apparatus 1 according to the fifth embodiment of the present invention. The film forming apparatus 1 according to the fifth embodiment is different from those according to the first, second, and third embodiments described above in that the substrate 2 has a circular or inclined rectangular or non-inclined attitude. When a plurality of convex portions 9 such as electrode films and parts are present on the rectangular film forming surface 2A, the amount of film liquid discharged from the required nozzle 4 of the ink jet head 3 is electrically variably controlled, and after drying The surface (upper surface) of the film 8A in FIG. Further, in this case as well, no bubbles are generated. Other controls are substantially the same as those in the first, second, and third embodiments described above.

  15A and 15B illustrate a film forming apparatus 1 according to the sixth embodiment of the present invention. The film forming apparatus 1 according to the sixth embodiment is different from those according to the first, second, and third embodiments described above in that a circular film forming surface 2A on a circular substrate 2 in plan view, In addition, a plurality of closed regions 10 in which no film is formed and regions 11 in which a film is formed are created on a film forming surface 2A having a rectangular or non-inclined posture in a rectangular shape in plan view. Other controls are substantially the same as those in the first, second, and third embodiments described above. In addition, you may apply the structure shown in above-mentioned FIG.7,8,9 not only to the outer peripheral edge part of 2 A of film formation surfaces but to the peripheral part of each closed region 10. FIG.

  16A and 16B illustrate a film forming apparatus 1 according to the seventh embodiment of the present invention. The film forming apparatus 1 according to the seventh embodiment is different from those according to the first, second, and third embodiments described above in that a circular film forming surface 2A on a circular substrate 2 in plan view, In addition, a plurality of closed regions 11 where a film is formed and regions 10 where a film is not formed are created on a film forming surface 2A having a rectangular or non-inclined posture on a rectangular substrate 2 in plan view. is there. Other controls are substantially the same as those in the first, second, and third embodiments described above. In addition, you may apply the structure shown in the above-mentioned FIG.7,8,9 to the peripheral part of each closed region 11. FIG.

  In the above embodiment, the film 8A after drying formed on the substrate 2 can have a lower limit of 300 nm and an upper limit of 30 μm or more, for example, 50 μm.

  Further, when the film 8A is formed by using the film forming apparatus 1 according to the above embodiment, 95% or more of the total discharge amount of the film liquid actually discharged from the inkjet head 3 is used for forming the film 8A. . Therefore, the waste film solution was less than 5% of the total discharge amount. In this case, the wasted film liquid is a small amount of film liquid coming out of the nozzle 4 when the surface of the nozzle 4 is cleaned before the film 8A is formed, and the nozzle surface after the surface of the nozzle 4 is cleaned. It is the sum total of the film solution that has been standby shot (discarded) by a small amount in order to adjust the thickness. Therefore, when the film 8A is actually formed on the film forming surface 2A of the substrate 2, 100% or almost 100% of the total discharge amount of the film liquid discharged from the inkjet head 3 is used for forming the film 8A. Will be.

  In the above embodiment, the outer peripheral ends 8b and 8Ab of the films 8 and 8A are positioned at the boundary 2d between the outer peripheral end 2b of the substrate 2 and the planar film forming surface 2A as shown in FIG. However, the outer peripheral ends 8b and 8Ab of the films 8 and 8A may be on the inner peripheral side or on the outer peripheral side with respect to the boundary 2d. Therefore, the configuration shown in FIG. 9 may also be on the inner peripheral side or the outer peripheral side with respect to the illustrated state.

  In the above embodiment, five individual inkjet heads 3 are used. However, the number is not limited. For example, only one individual inkjet head 3 may be used.

  Furthermore, in the above embodiment, the present invention is applied to the case where the film liquid 6 is discharged from all the nozzles 4 of the inkjet head 3 (in the case of 100% discharge state), but 70% to 95% or 85%. A discharge state of ˜95% may be used.

  The film solution 6 used in the above embodiment is not particularly limited as long as it forms a functional film such as a photosensitive insulating film, a non-photosensitive insulating film, a resist film, a UV film, or other films. It is not something.

  Furthermore, in the above embodiment, the formation of the film 8A is completed while the substrate 2 is moved once in the transport direction A. However, while the substrate 2 is moved twice or more (including reciprocating motion). The formation of the film 8A may be completed. In that case, the film formation surface 2A of the substrate 2 is divided into a plurality of regions as necessary, and for each region divided by one movement of the substrate 2. The film 8A may be formed.

  In addition, in the above embodiment, the substrate 2 is moved and the inkjet head 3 is fixedly installed. On the contrary, the inkjet head 3 may be moved and the substrate 2 may be fixedly installed. Alternatively, both 2 and 3 may move.

DESCRIPTION OF SYMBOLS 1 Film forming apparatus 2 Substrate 2A Substrate film forming surface 2b Substrate outer peripheral edge 2c Substrate back surface 3 Inkjet head 3a Individual inkjet head 4 Nozzle 5 Storage means 6 Film liquid 7 Control means 8 Film (film immediately after ejection)
8A membrane (membrane after drying)
9 Convex

Claims (5)

The inkjet head and the substrate are made non-contact with an ejection surface of an inkjet head in which a plurality of nozzles that eject film liquid are arranged in the width direction and a film formation surface of a substrate from which the film liquid is ejected from the nozzle. In the film forming apparatus configured to discharge the film liquid from the nozzle to the film forming surface of the substrate while relatively moving the both in a direction perpendicular to the width direction in a rotating state,
The arrangement width length of the nozzles of the inkjet head is set to be equal to or larger than the maximum length in the width direction of the film forming surface of the substrate when the substrate relatively moves,
A rectangular area comprising a film forming surface of the substrate having two sides parallel to the relative movement direction and a two sides perpendicular to the relative direction in which a corner portion is in contact with an outer peripheral end of the film forming surface; Divided into non-rectangular areas protruding from the
In the non-rectangular region, the number of nozzles that discharge the film liquid is changed with respect to the relative movement direction, and the film liquid from the nozzles increases as the number of nozzles that discharge the film liquid increases. A film forming apparatus characterized in that control is performed to increase the amount of ink discharged.   The non-rectangular region is divided into a plurality of partial regions in the relative movement direction, and different control is performed on the number of nozzles and the discharge amount of the film liquid from the nozzles depending on the difference of the partial regions. The film forming apparatus according to claim 1, wherein the film forming apparatus is configured to perform the following.   In the rectangular region, the number of nozzles for discharging the film liquid and the discharge amount of the film liquid from the nozzles are controlled to be constant regardless of the relative movement position. The film forming apparatus according to claim 1 or 2, characterized in that:   The rectangular region is disposed on both sides of the central rectangular region with respect to a direction perpendicular to the relative moving direction and a central rectangular region in which four corner portions are in contact with an outer peripheral end of the film forming surface, and the film formation It is divided into a lateral rectangular area where two corner portions are in contact with the outer peripheral edge of the surface, and the film solution is discharged regardless of the relative movement position in the central rectangular area and the lateral rectangular area. The film forming apparatus according to claim 1, wherein the control is performed so that the number of nozzles to perform and the discharge amount of the film liquid from the nozzles are made constant. The inkjet head and the substrate are made non-contact with an ejection surface of an inkjet head in which a plurality of nozzles that eject film liquid are arranged in the width direction and a film formation surface of a substrate from which the film liquid is ejected from the nozzle. In the film forming method of discharging the film liquid from the nozzle to the film forming surface of the substrate while relatively moving both in the direction perpendicular to the width direction in a rotating state,
The arrangement width length of the nozzles of the inkjet head is set to be equal to or larger than the maximum length in the width direction of the film forming surface of the substrate when the substrate relatively moves,
A rectangular area comprising a film forming surface of the substrate having two sides parallel to the relative movement direction and a two sides perpendicular to the relative direction in which a corner portion is in contact with an outer peripheral end of the film forming surface; Divided into non-rectangular areas protruding from the
In the non-rectangular region, the number of nozzles that discharge the film liquid is changed with respect to the relative movement direction, and the film liquid from the nozzles increases as the number of nozzles that discharge the film liquid increases. The film forming method is characterized in that control is performed to increase the discharge amount.

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