JP2013033879A - Drawing device and drawing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten drawing time per one drawing target sheet.SOLUTION: First and second nozzle units having a plurality of nozzles for discharging droplets face a drawing target retained by a retention mechanism. A shift mechanism shifts the first and second nozzle units relatively to the drawing target in mutually intersected first and second directions. A control device controls the nozzle units and the shift mechanism. Each nozzle of the first and second nozzle units is disposed so as to land the droplets at points of impact arranged at equal intervals in the second direction. The first and second nozzle units are arranged apart from each other in the second direction. Control by the control device causes an interval adjustment mechanism to change the interval between the first and second nozzle units.

Description

  The present invention relates to a drawing apparatus and a drawing method for drawing by discharging droplets from a nozzle.

  A conventional method for forming a solder resist pattern on a printed wiring board will be described. First, a photosensitive solder resist is applied to the entire surface of a printed wiring board having a circuit pattern formed on the surface. A solder resist pattern is formed by exposing the solder resist film using a predetermined mask pattern and then developing the solder resist film.

  Attention has been focused on a technique for forming a solder resist pattern by forming a solder resist into droplets, causing the droplets to adhere only to a desired region of the printed wiring board, and curing the solder resist. By irradiating the droplets attached to the surface of the printed wiring board with ultraviolet rays, the droplets can be cured.

Japanese Patent No. 3544543

  It is desired to shorten the drawing time per drawing object.

According to one aspect of the invention,
A holding mechanism for holding the drawing object;
First and second nozzle units having a plurality of nozzles facing the drawing object held by the holding mechanism and discharging droplets to the drawing object;
A moving mechanism that moves the first and second nozzle units in a first direction and a second direction that intersect with each other relative to the drawing object held by the holding mechanism;
A control device for controlling the first and second nozzle units and the moving mechanism;
The nozzles of each of the first and second nozzle units are arranged to land droplets on landing points arranged at equal intervals in the second direction,
The first and second nozzle units are spaced apart in the second direction;
Furthermore, there is provided a drawing apparatus having an interval adjusting mechanism that changes the interval between the first and second nozzle units under the control of the control device.

According to another aspect of the invention,
Preparing a drawing object in which a drawing pattern including a plurality of repeated patterns having the same outer shape and dimensions and spaced apart in the second direction is defined;
At least two nozzle units are made to face the drawing object, and the relative positional relationship between one repeating pattern and one nozzle unit in the second direction, and the second repeating pattern and the second nozzle unit. And the liquid droplets from the nozzle unit while moving the nozzle unit relative to the drawing object in a first direction perpendicular to the second direction. A drawing method including a step of performing main scanning for discharging the ink.

  By using a plurality of nozzle units, the drawing time can be shortened. By changing the interval between the first nozzle unit and the second nozzle unit, the relative positional relationship between the first nozzle unit and the second nozzle unit can be matched with the repetition cycle of the pattern to be drawn. it can. Thereby, variation in drawing quality can be suppressed.

FIG. 1 is a schematic diagram of a drawing apparatus according to an embodiment. FIG. 2A is a perspective view of the nozzle unit, and FIG. 2B is a bottom view of the nozzle unit. FIG. 3 is a diagram illustrating a positional relationship between the nozzle and the image of the nozzle. FIG. 4A is a view of the nozzle unit and the printed wiring board viewed from a line of sight orthogonal to the scanning direction, and FIG. 4B is a view of the nozzle unit and the printed wiring board viewed from a line of sight parallel to the scanning direction. FIG. 5 is a plan view of a printed wiring board that is a drawing object. 6A is a diagram illustrating a positional relationship between a repeated pattern of the printed wiring board according to the embodiment and a nozzle unit, and FIG. 6B is a cross-sectional view of the printed wiring board after drawing manufactured by the method according to the embodiment. FIG. 7A is a diagram showing a positional relationship between the repeated pattern of the printed wiring board according to the comparative example and the nozzle unit, and FIG. 7B is a cross-sectional view of the printed wiring board after drawing manufactured by the method according to the comparative example. It is a bottom view of the nozzle unit of the drawing apparatus by the modification of an Example.

  FIG. 1 is a schematic diagram of a drawing apparatus according to an embodiment. A holding mechanism 25 is held on the surface plate 20 by a moving mechanism 21. The moving mechanism 21 includes an X stage 22, a Y stage 23, and a θ stage 24. An XYZ orthogonal coordinate system in which the horizontal plane is the XY plane and the vertical direction is the Z axis is defined. The X stage 22 moves the Y stage 23 in the X-axis direction. The Y stage 23 moves the θ stage 24 in the Y direction. The θ stage 24 changes the posture of the holding mechanism 25 in the rotation direction about an axis parallel to the Z axis. The holding mechanism 25 holds the printed wiring board 50 that is a drawing target. For the holding mechanism 25, for example, a vacuum chuck is used.

  A beam 31 is supported by a support 30 above the surface plate 20. A nozzle unit 40 and an imaging device 32 are attached to the beam 31. A plurality of, for example, two nozzle units 40 are arranged in the Y direction. The interval of the nozzle unit 40 can be adjusted by the interval adjusting mechanism 46. The imaging device 32 and the nozzle unit 40 face the printed wiring board 50 held by the holding mechanism 25. The imaging device 32 images a wiring pattern, an alignment mark, and the like formed on the surface of the printed wiring board 50. The imaging result is input to the control device 33. The nozzle unit 40 ejects droplets of an ultraviolet curable resin, for example, a solder resist, from a plurality of nozzles toward the printed wiring board 50. The discharged droplets adhere to the surface of the printed wiring board 50.

  The control device 33 controls the X stage 22, the Y stage 23, the θ stage 24, the holding mechanism 25, and the nozzle unit 40. The storage device 34 stores image data of a pattern to be drawn.

  In FIG. 1, the moving mechanism 21 is arranged so that the nozzle head 40 is fixed to the surface plate 20 and the holding mechanism 25 is moved, but conversely, the holding mechanism 25 is fixed to the surface plate 20, and the nozzle The unit 40 may be moved with respect to the holding mechanism 25.

  FIG. 2A shows a perspective view of each nozzle unit 40. Four nozzle heads 42 </ b> A to 42 </ b> D are attached to the bottom surface of the support member 41 so as to be arranged in the X direction. The nozzle heads 42A to 42D are arranged in this order toward the negative direction of the X axis. A plurality of nozzles 45 are formed in each of the nozzle heads 42A to 42D.

  A light source 43 is disposed between the nozzle heads 42A and 42B, between the nozzle heads 42B and 42C, and between the nozzle heads 42C and 42D. Further, the light source 43 is arranged in a region on the positive side of the X axis from the nozzle head 42A and a region on the negative side of the X axis from the nozzle head 42D. The light source 43 irradiates the printed wiring board 50 (FIG. 1) with ultraviolet rays.

  FIG. 2B shows a bottom view of the nozzle heads 42 </ b> A to 42 </ b> D and the light source 43. Two rows of nozzle rows 46a and 46b are formed on the bottom surface of the nozzle head 42A (the surface facing the printed wiring board 50). Each of the nozzle row 46a and the nozzle row 46b includes a plurality of nozzles 45 arranged at a pitch (period) 8P in the Y-axis direction. The nozzle row 46b is shifted in the negative direction of the X axis with respect to the nozzle row 46a, and is further shifted by the pitch 4P in the negative direction of the Y axis. That is, the nozzles 45 of the nozzle head 42A are distributed at equal intervals with a pitch 4P in the Y direction. The pitch 4P is, for example, a pitch corresponding to a resolution of 300 dpi, that is, about 84.67 μm.

  The structure of the nozzle heads 42B to 42D is the same as the structure of the nozzle head 42A. The nozzle heads 42B, 42C, and 42D are mechanically positioned with respect to the nozzle head 42A so as to be shifted by 2P, P, and 3P in the negative direction of the Y axis, and are attached to the support member 41 (FIG. 2A). ing. A light source 43 is disposed between the nozzle heads 42A to 42D and outside the outermost nozzle heads 42A and 42D.

  As shown in FIG. 3, images 55A to 55D obtained by vertically projecting the nozzles 45 of the nozzle heads 42A to 42D onto a virtual plane 56 perpendicular to the X axis have a pitch P corresponding to a resolution of 1200 dpi in the Y direction, that is, about Arrange at equal intervals with a pitch of 21.17μ. For this reason, it is possible to perform drawing with a resolution of 1200 dpi in the Y-axis direction using the four nozzle heads 42A to 42D.

  FIG. 4A is a schematic diagram when the nozzle unit 40 and the printed wiring board 50 are viewed from a line of sight parallel to the Y axis. Nozzle heads 42 </ b> A to 42 </ b> D and a light source 43 are attached to the bottom surface of the support member 41. The printed wiring board 50 faces the nozzle heads 42A to 42D.

  The light source 43 attached between the nozzle heads 42A and 42B is located on the surface of the printed wiring board 50 between the region 48A facing the nozzle head 42A and the region 48B facing the nozzle head 42B. Irradiate light. Similarly, the region 48B facing the nozzle head 42B, the region 48C facing the nozzle head 42C, and the region 48D facing the nozzle head 42D are also illuminated by the light source 43 attached between the corresponding nozzle heads. Irradiated.

  The light source 43 attached to the outside of the nozzle head 42A (the positive side of the X axis) irradiates light on the region on the positive side of the X axis with respect to the region 48A. The light source 43 attached to the outside of the nozzle head 42D (the negative side of the X axis) irradiates light to the region on the negative side of the X axis from the region 48D.

  A case will be described in which drawing is performed by ejecting liquid droplets from the nozzle heads 42A to 42D while moving the printed wiring board 50 in the negative direction of the X axis. The droplets ejected from the nozzle heads 42A to 42D and adhered to the printed wiring board 50 are cured by being irradiated with light from a light source ahead (in the negative direction of the X axis) from the position of the droplet at the time of landing. To do.

  Since the light source 43 is disposed in front of each of the nozzle heads 42 </ b> A to 42 </ b> D, the droplets can be cured within a short time after the droplets adhere to the printed wiring board 50. Further, since the light source 43 is also arranged on the positive side of the X axis of each of the nozzle heads 42A to 42D, the liquid is also used when drawing while moving the printed wiring board 50 in the positive direction of the X axis. The time from the adhesion of the droplet to the curing can be shortened.

  FIG. 4B is a schematic diagram when the nozzle unit 40 and the printed wiring board 50 are viewed from a line of sight parallel to the X axis.

  The first nozzle unit 40A and the second nozzle unit 40B are arranged at an interval in the Y direction. The interval between the first nozzle unit 40A and the second nozzle unit 40B can be adjusted by the interval adjusting mechanism 46. Specifically, the first nozzle unit 40A and the second nozzle unit 40B can be independently moved in the Y direction. The interval adjusting mechanism 46 is controlled by the control device 33.

  FIG. 5 shows an example of a pattern to be drawn on the printed wiring board 50. A plurality of repetitive patterns 51 are arranged in a matrix in the X direction and the Y direction. Let the repetition period in the Y direction be L. When drawing is completed, the printed wiring board 50 is divided for each product. One repeating pattern 51 corresponds to one product substrate. The external shapes and dimensions of the plurality of repeating patterns 51 are the same. Moreover, all the repeating patterns 51 include the same drawing pattern therein. A solder resist is applied to a region outside the pattern arranged inside each repeating pattern 51.

  A drawing method according to the embodiment will be described with reference to FIG. 6A. The control device 33 (FIG. 1) calculates the repetition period L of the repeated pattern 51 from the image data of the pattern to be drawn stored in the storage device 34. The repetition period L may be obtained in advance from the pattern design data, and the repetition period L may be input to the control device 33.

  By moving the first nozzle unit 40A in the X direction and ejecting liquid droplets from the nozzle, it is possible to perform drawing in a band-like region extending in the X direction. Similarly, even in the second nozzle unit 40B, it is possible to perform drawing in a band-like region extending in the X direction.

  When the distance between the centers of the pixels defining the drawing pattern in the Y direction is equal to the pitch P (FIG. 3) of the nozzle images 55A to 55D, the nozzle unit 40 is moved in one direction parallel to the X axis. Thus, the drawing in the band-shaped area corresponding to the nozzle unit 40 is completed. When the pitch P of the nozzle images 55A to 55D is m times the distance between the centers of the pixels (m is a positive integer), the nozzle unit 40 is shifted by a distance (P / m) in the Y direction. By moving m times in the direction, drawing in the band-like region corresponding to the nozzle unit 40 is completed. For example, when m = 2, the drawing in the band-like region is completed by reciprocating one nozzle unit 40 once. The process of moving the nozzle unit 40 m times in the X direction to complete the drawing in the band-like region corresponding to the nozzle unit 40 is referred to as “one main scan”.

  An area where drawing is performed in one main scan is referred to as a “unit scan area”. Let W be the maximum width of the unit scan area. The maximum width W is equal to the length obtained by adding the pitch P to the interval between the nozzle images at both ends of the nozzle images 55A to 55D in FIG. When the total number of nozzles 45 is N, W = N × P. The maximum width W of the unit scanning area is narrower than the repetition period L of the repeating pattern 51.

  The control device 33 controls the interval adjusting mechanism 46 (FIG. 4B) to match the relative positional relationship in the Y direction between the first nozzle unit 40A and the second nozzle unit 40B with the repetition period L. Specifically, as an example, the amount of deviation of the second nozzle unit 40B in the Y direction with respect to the first nozzle unit 40A is made the same as the repetition period L. At this time, the relative positional relationship in the Y direction between the repetitive pattern 51 in the first row and the first nozzle unit 40A is the relative positional relationship in the Y direction between the repetitive pattern 51 in the second row and the second nozzle unit 40B. Are the same.

  Note that the shift amount in the Y direction of the second nozzle unit 40B relative to the first nozzle unit 40A may be an integral multiple of the repetition period L.

  A plurality of regions in which the first-row repeating pattern 51 is arranged are divided into three unit scanning regions 60A (1) to 60A (3) in FIG. 6A, and the second-row repeating pattern 51 is arranged. The region is divided into three unit scanning regions 60B (1) to 60B (3). When the unit scanning regions 60A (1) to 60A (3) are shifted by the repetition period L in the Y direction, they coincide with the unit scanning regions 60B (1) to 60B (3).

  The repetition period L is not always divisible by the maximum width W of the unit scanning area. If it is not divisible, at least one of the three unit scan areas 60A (1) to 60A (3) dividing the repetitive pattern 51 in the first column is narrower than W. FIG. 6A shows an example in which the width of the unit scanning area 60A (3) is narrower than W. Note that the width of each of the unit scan regions 60A (1) to 60A (3) may be L / 3.

  By performing the first main scan by the first and second nozzle units 40A and 40B, the drawing in the unit scan areas 60A (1) and 60B (1) is completed. The positions of the first and second nozzle units 40A and 40B at the time of the first main scanning are indicated by solid lines. The first and second nozzle units 40A and 40B are shifted by W in the Y direction to perform the second main scan. Thereby, the drawing in the unit scan areas 60A (2) and 60B (2) is completed. Furthermore, by performing the third main scan, the drawing in the unit scan areas 60A (3) and 60B (3) is completed. The positions of the first and second nozzle units 40A and 40B at the second and third main scans are indicated by broken lines.

  An area that can be drawn by the first nozzle unit 40A at the time of the third main scan is partially different from the unit scan area 60B (1) drawn by the second nozzle unit 40B at the first main scan. May overlap. In this case, the overlapping region is not drawn by the first nozzle unit 40A.

  FIG. 6B shows a cross-sectional view of the solder resist film 53 after drawing. The widths of the unit scan areas 60A (3) and 60B (3) are narrower than the widths of the other unit scan areas. For this reason, the number of nozzles that eject droplets in the third main scan is smaller than the number of nozzles that eject droplets in the first and second main scans. When main scanning is performed with a small number of nozzles for discharging the solder resist, the volume of droplets discharged from the nozzles tends to increase. This is presumably because the solder resist has a higher viscosity than general printing ink.

  Since the width of the unit scanning regions 60A (3) and 60B (3) is narrower than the width of the other unit scanning regions, the film thickness of the solder resist film 53 formed in the unit scanning regions 60A (3) and 60B (3). However, it becomes thicker than the film thickness of the solder resist film 53 formed in other unit scanning regions. The distribution of the thickness of the solder resist film 53 for each repeated pattern 51 is the same for all the repeated patterns 51. Since one repetitive pattern 51 corresponds to one product, the variation in the quality of the solder resist film between products is reduced.

  In the embodiment, since drawing is performed using the two nozzle units 40, the drawing time can be shortened.

  FIG. 7A shows the positional relationship between the repetitive pattern 51 and the unit scanning regions 60A (1) to 60A (3) and 60B (1) to 60B (3) when drawing is performed by the method according to the comparative example. In the comparative example, the amount of deviation in the Y direction between the first nozzle unit 40A and the second nozzle unit 40B is fixed to three times the maximum width W of the unit scanning region.

  The unit scan region 60A (3) partially overlaps the repeating pattern 51 of two adjacent columns. The repetitive pattern 51 in the first column and the repetitive pattern 51 in the second column differ in the positional relationship between the boundary line of the unit scanning region and the repetitive pattern 51.

  FIG. 7B shows a cross-sectional view of the solder resist film 53 formed by the method according to the comparative example. When the unit scan region 60A (3) is scanned, no liquid droplet is applied to the blank portion between the repetitive pattern 51 in the first row and the repetitive pattern 51 in the second row. For this reason, the number of nozzles used when scanning the unit scan region 60A (3) is smaller than when scanning other unit scan regions. Therefore, the thickness of the solder resist film 53 in the unit scanning region 60A (3) is thicker than other regions.

  The film thickness distribution in the repeating pattern 51 in the first column is different from the film thickness distribution in the repeating pattern 51 in the second column. For this reason, the quality of the solder resist film varies greatly among products.

  By adopting the drawing apparatus and the drawing method according to the embodiment, the quality of the solder resist film can be suppressed from product to product.

  In the above embodiment, two nozzle units 40 are arranged, but three or more nozzle units 40 may be arranged. At this time, the relative positional relationship in the Y direction between one repetitive pattern 51 and the corresponding nozzle unit 40, and the relative positional relationship in the Y direction between the other one repetitive pattern 51 and the corresponding nozzle unit 40, Are the same. In this state, droplets are ejected from the nozzle unit while moving the nozzle unit 40 in the X direction relative to the drawing object 50. Thereby, the dispersion | variation between products of the quality of a soldering resist film | membrane can be suppressed.

  FIG. 5 shows an example in which the same repetitive pattern 51 is arranged in a matrix in the X direction and the Y direction. However, the same pattern does not necessarily have to be periodically arranged in the X direction. For example, in FIG. 5, the repetitive pattern 51 arranged in the first row and the repetitive pattern 51 arranged in the second row do not have to have the same internal pattern and outer dimensions. However, even if the dimensions of the outer shape are not the same, the repeating pattern 51 on the first line and the repeating pattern 51 on the second line need to be arranged with the same repetition period L in the Y direction.

  FIG. 8 shows a bottom view of a nozzle unit of a drawing apparatus according to a modification of the embodiment. Hereinafter, description will be made by paying attention to differences from the embodiment, and description of the same configuration will be omitted.

  In the above embodiment, two nozzle rows 46a and 46b are formed in each of the nozzle heads 42A to 42D. However, in a modified example, one nozzle row 46 is formed. The nozzle row 46 includes a plurality of nozzles 45 arranged in the Y direction at a pitch of 4P. In the embodiment, the liquid droplets are landed on one straight line by shifting the discharge time from the two nozzle rows 46a and 46b. However, in the modified example, from the nozzle 45 in one nozzle head, What is necessary is just to discharge a droplet simultaneously.

  When the nozzles 45 of one nozzle head 42A, 42B, 42C or 42D are arranged at a pitch corresponding to 300 dpi, even in the modified example, drawing is performed at a resolution of 1200 dpi using the four nozzle heads 42A to 42D. It can be carried out.

  The nozzle unit 40 may be configured by a single nozzle head having a plurality of nozzles 45 arranged in a line at a pitch P.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications, improvements, combinations, and the like can be made.

20 Surface plate 21 Moving mechanism 22 X stage 23 Y stage 24 θ stage 25 Holding mechanism 30 Support column 31 Beam 32 Imaging device 33 Control device 34 Storage device 40 Nozzle unit 40A First nozzle unit 40B Second nozzle unit 41 Support member 42A , 42B, 42C, 42D Nozzle head 43 Light source 45 Nozzle 46 Spacing adjustment mechanism 50 Printed wiring board (drawing object)
51 Repeat Pattern 53 Solder Resist Film 60A Unit Scanning Area 60B of First Nozzle Unit Unit Scanning Area of Second Nozzle Unit

Claims (4)

A holding mechanism for holding the drawing object;
First and second nozzle units having a plurality of nozzles facing the drawing object held by the holding mechanism and discharging droplets to the drawing object;
A moving mechanism that moves the first and second nozzle units in a first direction and a second direction that intersect with each other relative to the drawing object held by the holding mechanism;
A control device for controlling the first and second nozzle units and the moving mechanism;
The nozzles of each of the first and second nozzle units are arranged to land droplets on landing points arranged at equal intervals in the second direction,
The first and second nozzle units are spaced apart in the second direction;
Furthermore, the drawing apparatus which has the space | interval adjustment mechanism which changes the space | interval of the said 1st and 2nd nozzle unit by control from the said control apparatus. The drawing pattern to be drawn on the drawing object includes a plurality of repetitive patterns having the same outer shape and dimensions and arranged at intervals in the second direction,
The control measures are:
Controlling the interval adjusting mechanism so that the relative positions of the first and second nozzle units in the second direction are aligned with a repetition period in which the repetition pattern is aligned in the second direction;
A drawing object in which the first and second nozzle units are held by the holding mechanism in a state where the relative positions of the first and second nozzle units in the second direction are aligned with the repetition period. The drawing apparatus according to claim 1, wherein the drawing is performed while relatively moving in the first direction. Preparing a drawing object in which a drawing pattern including a plurality of repeated patterns having the same outer shape and dimensions and spaced apart in the second direction is defined;
At least two nozzle units are made to face the drawing object, and the relative positional relationship between one repeating pattern and one nozzle unit in the second direction, and the second repeating pattern and the second nozzle unit. And the liquid droplets from the nozzle unit while moving the nozzle unit relative to the drawing object in a first direction perpendicular to the second direction. A drawing method including a step of performing main scanning for discharging the ink. The width in the second direction of the region that can be drawn by relatively moving one nozzle unit in the first direction is larger than the dimension in the second direction of each of the repeated patterns. small,
The drawing method according to claim 3, wherein the main scanning is performed a plurality of times by changing a position of the nozzle unit in the second direction.

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