JP2013237004A - Thin film forming position, and repairing method and adjusting method for thin film forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin film forming device which can swiftly perform recovery processing when a failure occurs in a nozzle hole.SOLUTION: A base is held by a holding face of a stage. A nozzle head is opposed to the base held by the stage. The nozzle head has a plurality of nozzle holes for discharging droplets of thin film materials toward the base. A moving mechanism moves the stage to a direction in parallel with the holding face with respect to the nozzle head. An imaging device is configured to be able to move to the nozzle head, and to move to a position at which the nozzle holes can be imaged.

Description

  The present invention relates to a thin film forming apparatus that forms a thin film pattern by discharging droplets of a thin film material from a plurality of nozzle holes, a repair method for the thin film forming apparatus, and an adjustment method.

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. Solder resist droplets are ejected from a plurality of nozzle holes toward the printed wiring board. By irradiating the droplets attached to the surface of the printed wiring board with ultraviolet rays, the droplets can be cured.

JP 2004-104104 A

A liquid material such as a solder resist may cause defects such as clogging in the nozzle holes. When a defect occurs in the nozzle hole, it is preferable to quickly perform a defect recovery process (repair process) of the nozzle hole in order to shorten the stop time of the thin film forming apparatus.
An object of the present invention is to provide a thin film forming apparatus and a method for repairing the thin film forming apparatus that can quickly perform a recovery process when a defect occurs in a nozzle hole. Another object of the present invention is to provide a method for adjusting the relative positions of a plurality of nozzle heads mounted on a thin film forming apparatus.

According to one aspect of the invention,
A stage for holding the substrate on the holding surface;
A nozzle head formed with a plurality of nozzle holes facing a substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
There is provided a thin film forming apparatus having an imaging device which is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged.

According to another aspect of the invention,
A stage for holding the substrate on the holding surface;
A nozzle head formed with a plurality of nozzle holes facing a substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
A method of repairing a thin film forming apparatus having an imaging device that is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged;
When a defect occurs in the thin film formed on the substrate, it is possible to estimate the position of the suspected area including the defective nozzle hole that caused the defect based on the position where the defect has occurred, and to image the suspected area Moving the imaging device to a position;
Imaging the suspected area with the imaging device;
There is provided a method of repairing a thin film forming apparatus including a step of identifying a defective nozzle hole based on a captured image.

According to yet another aspect of the invention,
A stage for holding the substrate on the holding surface;
A plurality of nozzle heads formed with a plurality of nozzle holes facing the substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
An adjustment method of a thin film forming apparatus having an imaging device that is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged,
Moving the imaging device to a position where the nozzle head can image, and imaging at least two nozzle heads;
And adjusting a relative position of the plurality of nozzle heads based on an image obtained by imaging the nozzle head.

  By imaging a nozzle hole with an imaging device, it is possible to identify a nozzle hole in which a defect has occurred from a plurality of nozzle holes. Thereby, the recovery process of a nozzle hole can be performed rapidly.

FIG. 1 is a schematic view of a thin film forming apparatus according to an embodiment. FIG. 2 is a perspective view of the stage, the imaging device, the repair device, and the nozzle unit of the thin film forming apparatus according to the embodiment. 3A is a perspective view of the nozzle unit, and FIG. 3B is a bottom view of the nozzle unit. 4A is a plan view of the thin film pattern formed on the substrate, and FIG. 4B is a plan view of the thin film pattern including a defective portion formed on the substrate. FIG. 5 is a flowchart of the repair method of the thin film forming apparatus according to the embodiment. FIG. 6 is a cross-sectional view of the nozzle unit and the imaging device. FIG. 7 is a diagram illustrating the positional relationship between the nozzle unit and the imaging range of the imaging device. FIG. 8 is a diagram illustrating a positional relationship between a nozzle unit and an imaging range of an imaging device for explaining a method for adjusting a thin film forming apparatus according to another embodiment. FIG. 9 is a diagram illustrating a positional relationship between a nozzle unit and an imaging range of the imaging apparatus for explaining a method for adjusting a thin film forming apparatus according to a modification of another embodiment.

FIG. 1 is a schematic view of a thin film forming apparatus according to an embodiment. A stage 25 is supported on the surface plate 20 by a moving mechanism 21. A substrate 30 such as a printed wiring board is held on the upper surface (holding surface) of the stage 25. An XYZ orthogonal coordinate system is defined in which the directions parallel to the holding surface of the stage 25 are the X direction and the Y direction, and the normal direction of the holding surface is the Z direction. The moving mechanism 21 moves the stage 25 in the X direction and the Y direction.

  A beam 27 is supported by a column 26 above the surface plate 20. A nozzle unit support mechanism 41 and an imaging device 42 are attached to the beam 27. The nozzle unit 40 is supported by the nozzle unit support mechanism 41. The imaging device 42 and the nozzle unit 40 face the substrate 30 held on the stage 25. The imaging device 42 images a wiring pattern, an alignment mark, a thin film pattern formed on the substrate 30 and the like formed on the surface of the substrate 30. Image data obtained by imaging is input to the control device 33. The nozzle unit 40 discharges droplets of an ultraviolet curable thin film material, for example, droplets of solder resist or the like, from the plurality of nozzle holes toward the substrate 30. The discharged thin film material adheres to the surface of the substrate 30.

  Instead of fixing the nozzle unit 40 to the surface plate 20 and moving the stage 25, the nozzle unit 40 may be moved relative to the stage 25.

  An imaging device 50 is attached to the stage 30. By moving the stage 30 and arranging the imaging device 50 directly below the nozzle unit 40, the imaging device 50 can image some of the nozzle holes of the nozzle unit 40.

  The control device 33 controls the moving mechanism 21, the nozzle unit 40, and the imaging devices 42 and 50. The control device 33 stores image data of a thin film pattern to be formed on the substrate 30. An operator inputs various commands (commands) and numerical data necessary for control to the control device 33 through the input device 35. For the input device 35, for example, a keyboard, a touch panel, a pointing device, or the like is used. The control device 33 outputs various information from the output device 36 to the operator. A liquid crystal display or the like is used for the output device 36.

  FIG. 2 is a perspective view of the stage 25, the nozzle unit 40, and the nozzle unit support mechanism 41 of the thin film forming apparatus according to the embodiment. The substrate 30 is held on the holding surface of the stage 25. A nozzle unit 40 is supported above the substrate 30. The nozzle unit 40 includes a nozzle holder 45 and a plurality of nozzle heads 46 fixed to the nozzle holder 45. A plurality of nozzle holes are provided on the surface of the nozzle head 46 facing the substrate 30.

  The nozzle unit support mechanism 41 includes a goniometer 47 and an elevating mechanism 48. The goniometer 47 can rotate the nozzle unit 40 within a certain angle range around an axis parallel to the Z axis. The lifting mechanism 48 moves the nozzle unit 40 in the Z direction.

  An imaging device 50 is attached to the edge of the stage 25. For the imaging device 50, for example, a CCD camera or the like is used. By moving the stage 25 and disposing the imaging device 50 directly below the nozzle unit 40, it is possible to image some of the nozzle holes. The imaging device 50 is controlled by the control device 33, and the captured image data is input to the control device 33. Note that a license sensor may be used as the imaging device 50. When a line sensor is used, the control device 33 acquires a plurality of one-dimensional images while moving the stage 25. A plurality of acquired one-dimensional images can be combined to generate a two-dimensional image.

  The illumination device 51 illuminates the nozzle holes in the imaging range. As an illumination method, for example, coaxial epi-illumination is adopted. The illumination light includes only a wavelength region that does not cure the liquid thin film material, and does not include an ultraviolet wavelength that cures the thin film material.

  A repair device 53 is further attached to the stage 25. By moving the repair device 53 below the nozzle unit 40, clogging of the nozzle holes and the like are recovered. The repair device 53 is controlled by the control device 33. Examples of methods for recovering nozzle clogging include purge, suction, and wipe.

  The purge is a process of applying a positive pressure to the space in the nozzle head 46 that houses the thin film material. Normally, a negative pressure is applied to the space in which the thin film material is accommodated. When purging, liquid thin film material flows out from the nozzle holes. The repair device 53 is provided with a tray that receives the thin film material that has flowed from the nozzle holes.

  Suction is a process of sucking out foreign matter or the like in the nozzle hole by applying a negative pressure to the space outside the nozzle hole. The repair device 53 houses a suction device that applies a negative pressure to the nozzle holes. Wiping is a process of wiping the surface of the nozzle unit 40 where the nozzle holes are provided with a wiper. The repair device 53 is provided with a wiper.

  FIG. 3A shows a perspective view of the nozzle unit 40. A plurality of, for example, four nozzle heads 46 are attached to the nozzle holder 45. A plurality of nozzle holes 55 are formed in each of the nozzle heads 46. Ultraviolet light sources 56 are arranged on the outer sides of the outermost nozzle heads 46 in the X direction. The ultraviolet light source 56 irradiates the substrate 30 (FIGS. 1 and 2) with ultraviolet rays.

  FIG. 3B shows a bottom view of the nozzle head 46 and the ultraviolet light source 56. Two nozzle rows 57 are arranged on the bottom surface (surface facing the substrate 30) of each nozzle head 46. Each of the nozzle rows 57 includes a plurality of nozzle holes 55 arranged at a pitch (period) 8P in the Y direction. One nozzle row 57 is shifted in the X direction with respect to the other nozzle row 57, and is further shifted by a pitch 4P in the Y direction. That is, when focusing on one nozzle head 46, the nozzle holes 55 are distributed at equal intervals with a pitch 4P in the Y direction. The pitch 4P corresponds to a resolution of 300 dpi, for example.

  The four nozzle heads 46 are arranged in the X direction and are offset from each other in the Y direction and attached to the nozzle holder 45 (FIG. 3A). In FIG. 3B, with the leftmost nozzle head 46 as a reference, the second, third, and fourth nozzle heads 46 are shifted by 2P, P, and 3P, respectively, in the negative direction of the Y-axis. For this reason, when paying attention to the four nozzle heads 46, the nozzle holes 55 are arranged at a pitch P (a pitch corresponding to 1200 dpi) in the Y direction.

  Ultraviolet light sources 56 are arranged on the outer sides of the outermost nozzle heads 46 in the X direction. The ultraviolet light source 56 cures the liquid thin film material attached to the substrate 30 (FIGS. 1 and 2). Further, an ultraviolet light source may be disposed between the nozzle heads 46. If an ultraviolet light source is also disposed between the nozzle heads 46, the time from when the droplet of the thin film material lands on the substrate 30 to curing can be shortened.

  A thin film pattern can be formed with a resolution of 1200 dpi in the Y direction by ejecting droplets of a thin film material from each nozzle hole 55 of the nozzle unit 40 while moving the substrate 30 (FIG. 1) in the Y direction. By performing reciprocal scanning while shifting by P / 2 in the Y direction, the resolution in the Y direction can be doubled to 2400 dpi. The resolution in the X direction is determined by the moving speed of the substrate 30 and the droplet discharge period from the nozzle hole 55.

FIG. 4A shows a plan view of the thin film pattern 31 formed on the substrate 30. For example, the thin film pattern 31 includes a plurality of congruent patterns arranged in a matrix. Image data of the thin film pattern 31 to be formed is stored in the control device 33 (FIG. 1). When a defect such as nozzle clogging occurs in some of the nozzle holes 55 (FIGS. 3A and 3B), a linear defect portion 32 parallel to the X direction appears as shown in FIG. 4B.

  FIG. 5 shows a flowchart of a repair method of the thin film forming apparatus according to the embodiment. As shown in FIG. 4B, when a defective portion 32 appears in the formed thin film pattern 31, the position in the Y direction of the nozzle hole that is considered defective is estimated from the position of the defective portion 32 in step S1. However, the position of the defective nozzle hole can be narrowed down to a certain region only from the position of the defective portion 32, but it is difficult to specify the nozzle hole 55 (defective nozzle hole) where the defect has occurred. . A region where a defective nozzle hole is estimated to be present is referred to as a “suspected region”. The suspicious area includes a plurality of nozzle holes. Further, since it is difficult to specify the nozzle head 46 to which the defective nozzle hole 55 belongs, a suspicious area is defined for each nozzle head 46.

  In step S2, the suspicious area of each nozzle head 46 is imaged by the imaging device 50 (FIGS. 1 and 2). Specifically, the operator inputs position information in the Y direction of the suspected area from the input device 35 (FIG. 1). This position information may be position information based on the nozzle head 46 shown in FIG. 3B or position information based on the substrate 30 shown in FIG. 4B. When position information based on the substrate 30 is input, the control device 33 (FIGS. 1 and 2) converts the position information based on the substrate 30 into position information based on the nozzle head 46. As shown in FIG. 6, the control device 33 moves the stage 25 to move the imaging device 50 to a position immediately below the suspected region of each nozzle head 46.

  It is also possible to adopt a method of automatically detecting the position of the suspicious area instead of the operator inputting the position information of the suspicious area. Next, a method for automatically detecting the position of the suspicious area will be described. First, after the thin film pattern 31 (FIG. 4A) is formed on the substrate 30, the thin film pattern 31 is imaged by the imaging device 42 (FIG. 1). By automatically analyzing the captured image, it is determined whether or not there is a defective portion 32 (FIG. 4B). When the defective part 32 is detected, the position of the suspected area is calculated based on the position of the defective part 32.

  FIG. 7 shows the positional relationship between the nozzle hole 55 and the imaging range 52 of the imaging device 50 (FIG. 6). For example, 3 to 4 nozzle holes 55 belonging to one nozzle head 46 are accommodated in the imaging range 52. By moving the stage 25 (FIG. 6) in the X direction, the suspected areas of the four nozzle heads 46 can be sequentially accommodated in the imaging range 52 and imaged. The control device 33 displays the captured image on the output device 36.

  In step S <b> 3, the operator identifies the defective nozzle hole and the nozzle head 46 in which the defective nozzle hole exists by observing the image displayed on the output device 36. In step S4, the operator determines whether or not the defective nozzle hole 55 can be recovered. For example, when a bubble stays in the defective nozzle hole 55, or when a minute foreign matter remains in the defective nozzle hole 55, it is determined that the defective nozzle hole 55 can be recovered. When the thin film material is solidified in the defective nozzle hole 55, or when the defective nozzle hole 55 is deformed, it is determined that the defective nozzle hole cannot be recovered.

  If it is determined that the defective nozzle hole 55 cannot be recovered, the nozzle head 46 to which the defective nozzle hole 55 belongs is replaced with a new nozzle head in step S9. When it is determined in step S4 that the defect is recoverable, in step S5, the operator inputs information for specifying the defective nozzle hole 55 and an execution command for the repair process from the input device 35. The information for specifying the defective nozzle hole 55 includes information for specifying the nozzle head 46 and information for specifying the nozzle hole 55 in the nozzle head 46.

  In step S <b> 6, the control device 33 (FIGS. 1 and 2) performs a repair process on the defective nozzle hole 55. Specifically, the repair device 53 is moved to just below the defective nozzle hole 55. Thereafter, suction, wipe, purge, etc. are performed. Suction is performed only on the defective nozzle hole 55 or on the nozzle holes in the vicinity thereof. Wiping and purging are performed on the nozzle head 46 to which the defective nozzle hole 55 belongs.

  When the repair process ends, in step S7, the nozzle hole 55 after the repair process is imaged by the imaging device 50 (FIG. 6). The control device 33 displays the acquired image on the output device 36 (FIG. 1). In step S <b> 8, the operator determines whether the defect of the nozzle hole 55 has been recovered by observing the image displayed on the output device 36. If it is determined that the defect has been recovered, the repair process is terminated. If it is determined that the defect has not recovered, the nozzle head 46 including the defective nozzle hole 55 is replaced with a new nozzle head in step S9.

  In the above embodiment, the nozzle hole 55 (FIGS. 3A and 3B) can be observed with the imaging device 50 (FIGS. 1 and 2) without removing the nozzle head 46 from the nozzle holder 45. For this reason, when the defective part 32 (FIG. 4B) appears in the thin film pattern 31, the state and position of a defective nozzle hole can be specified easily. Thereby, the time for the repair process can be shortened.

  In addition, the wiping performed in step S6 (FIG. 5) may be able to recover the defective nozzle hole 55, but conversely may cause clogging of the normal nozzle hole 55. In the embodiment, only the nozzle head 46 to which the defective nozzle hole 55 belongs is wiped, and the normal nozzle head 46 is not wiped. For this reason, generation | occurrence | production of the defect resulting from a wipe can be prevented.

  In the above embodiment, in step S3 (FIG. 5), the operator has identified the nozzle hole 55 in which a defect has occurred by observing the image of the nozzle hole. The control device 33 (FIG. 2) may perform automatic image analysis without an operator to identify the nozzle hole 55 in which a defect has occurred and determine whether or not it can be recovered. . By storing image data of various defective nozzle holes and information on whether or not recovery is possible, automatic analysis of the image can be performed.

  In the above embodiment, the imaging device 50 (FIGS. 1 and 2) is used to identify the nozzle hole 55 in which a defect has occurred. The imaging device 50 may have a lower magnification so that a wider surface of the nozzle head 46 can be observed. Thereby, the state of dirt on the surface of the nozzle head 46 can be observed.

  In the above embodiment, as shown in FIG. 2, the imaging device 50 and the repair device 53 are attached to the stage 25 for the substrate 30, but separately from the stage 25 for the substrate 30, the imaging device 50 and the repair device 53. A stage may be arranged. Thereby, the weight of the stage 25 for the substrate 30 can be reduced. Alternatively, the imaging device 50 and the repair device 53 may be fixed to the surface plate 20 (FIG. 1), and the nozzle unit 40 may be moved to above the imaging device 50 or the repair device 53.

  Next, a method for adjusting a thin film forming apparatus according to another embodiment will be described with reference to FIG. In this adjustment method, after the plurality of nozzle heads 46 are attached to the nozzle holder 45 shown in FIG. 3A, the relative positions of the plurality of nozzle heads 46 are adjusted.

  As shown in FIG. 8, the imaging device 50 is arranged so that a nozzle hole (hereinafter referred to as “reference nozzle hole”) 55 r serving as a reference for one nozzle head 46 is included in the imaging range 52 of the imaging device 50. Move and get the image. Similarly, the reference nozzle hole 55r of another nozzle head 46 is imaged.

  By analyzing the captured image, the relative positional relationship of the reference nozzle holes 55r of the plurality of nozzle heads 46 is obtained. Based on the calculation result, the relative position of the nozzle head 46 is adjusted so that the reference nozzle hole 55r is arranged at the target position. Fine adjustment of the position of the nozzle head 46 can be performed by a fine adjustment screw or the like.

  As shown in FIG. 9, the edges of the two nozzle heads 46 that are adjacent to each other may be arranged within the imageable range 52 to image the edges of the nozzle head 46. By analyzing the captured image, the relative positional relationship of the plurality of nozzle heads 46 can be obtained.

  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 25 Stage 26 Column 27 Beam 31 Substrate 31 Thin film pattern 32 Defect location 33 Control device 35 Input device 36 Output device 40 Nozzle unit 41 Nozzle unit support mechanism 42 Imaging device 45 Nozzle holder 46 Nozzle head 47 Goniometer 48 Mechanism 50 Imaging device 51 Illumination device 52 Imaging range 53 Repair device 55 Nozzle hole 55r Nozzle hole 56 serving as a reference Ultraviolet light source 57 Nozzle array

Claims (10)

A stage for holding the substrate on the holding surface;
A nozzle head formed with a plurality of nozzle holes facing a substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
A thin film forming apparatus comprising: an imaging device which is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged.   The thin film forming apparatus according to claim 1, wherein the imaging device is attached to the stage. And a control device for controlling the movement of the imaging device,
3. The thin film forming apparatus according to claim 1, wherein the control device moves the imaging device to a position where an image of a suspected region where a defective nozzle hole is estimated to be present can be imaged.   The thin film according to claim 3, further comprising an input device operated by an operator, wherein the position information of the suspected area is given to the control device when the operator inputs the position information of the suspected area from the input device. Forming equipment. And an output device for displaying an image captured by the imaging device,
The thin film forming apparatus according to claim 1, wherein the control device displays an image captured by the imaging device on the output device. Furthermore, it has a repair device that performs a recovery process of the nozzle hole under the control of the control device,
The control device includes:
The thin film forming apparatus according to claim 5, wherein when the repair processing execution command and information for specifying a defective nozzle hole are input from the input device, the repair device is controlled to perform recovery processing of the defective nozzle hole. . Furthermore, it has a repair device that performs a recovery process for defective nozzle holes under the control of the control device,
The control device includes:
The imaging device is moved to a position where the suspicious area input from the input device can be imaged, image analysis of the captured image is performed, and a defective nozzle hole is identified based on the image analysis result. The thin film forming apparatus according to claim 4, wherein the repair apparatus is controlled to perform a recovery process for the specified defective nozzle hole. A stage for holding the substrate on the holding surface;
A nozzle head formed with a plurality of nozzle holes facing a substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
A method of repairing a thin film forming apparatus having an imaging device that is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged;
When a defect occurs in the thin film formed on the substrate, it is possible to estimate the position of the suspected area including the defective nozzle hole that caused the defect based on the position where the defect has occurred, and to image the suspected area Moving the imaging device to a position;
Imaging the suspected area with the imaging device;
A method of repairing a thin film forming apparatus, comprising a step of identifying a defective nozzle hole based on a captured image. The method for repairing a thin film forming apparatus according to claim 8, further comprising a step of determining whether to perform recovery processing of the defective nozzle hole or replacement of the nozzle head based on the image. A stage for holding the substrate on the holding surface;
A plurality of nozzle heads formed with a plurality of nozzle holes facing the substrate held on the stage and discharging droplets of a thin film material toward the substrate;
A moving mechanism for moving one of the stage and the nozzle head in a direction parallel to the holding surface with respect to the other;
An adjustment method of a thin film forming apparatus having an imaging device that is movable with respect to the nozzle head and configured to be movable to a position where the nozzle hole can be imaged,
Moving the imaging device to a position where the nozzle head can image, and imaging at least two nozzle heads;
Adjusting a relative position of the plurality of nozzle heads based on an image obtained by imaging the nozzle heads.

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