JPWO2013011775A1 - Thin film forming method and thin film forming apparatus - Google Patents

Abstract

  By repeatedly landing the droplet of the thin film material on the edge of the region where the thin film pattern is formed on the surface of the substrate and curing of the landed thin film material, the thin film material is applied to the edge of the region where the thin film pattern is formed. An edge pattern is formed. A thin film material droplet is landed on an inner region whose edge is defined by an edge pattern. The thin film material that has landed on the inner region is cured. A thin film pattern composed of an edge pattern and a thin film material landed on the inner region is formed.

Description

  The present invention relates to a thin film forming method and a thin film forming apparatus for forming a thin film pattern by discharging droplets of a thin film material toward a substrate.

  A technique for forming a thin film pattern on the surface of a substrate by discharging droplets containing a material for forming a thin film pattern from a nozzle head (inkjet head) is known (for example, Patent Document 1).

  In such a thin film forming technique, for example, a printed wiring board is used as a substrate, and a solder resist is used as a thin film material. The printed wiring board includes a base material and wiring, and an electronic component or the like is soldered to a predetermined position. The solder resist exposes a conductor portion for soldering an electronic component or the like and covers a portion that does not require soldering. A region where a conductor portion is exposed for soldering an electronic component or the like is called a land.

Japanese Patent No. 3544543

As the thin film material, a light curable (for example, ultraviolet curable) liquid material is used. When the thin film material droplets land on the substrate, the thin film material spreads in the in-plane direction. In order to increase the resolution of the thin film pattern formed on the substrate, it is preferable to quickly irradiate the thin film material with light after the droplets have landed. However, in a region where the thin film is applied to the solid, if the thin film material is quickly cured after the droplets have landed, irregularities remain on the surface of the thin film corresponding to each of the droplets.
An object of the present invention is to provide a thin film forming method and a thin film forming apparatus in which unevenness is hardly generated on the surface of the thin film.

According to one aspect of the invention,
The thin film material is formed at the edge of the region where the thin film pattern is formed by repeating the landing of the droplet of the thin film material on the edge of the region where the thin film pattern is formed on the surface of the substrate and the curing of the landed thin film material. Forming an edge pattern comprising:
Landing a droplet of thin film material on an internal region defined by an edge pattern;
There is provided a thin film forming method including a step of curing a thin film material landed on the internal region.

According to another aspect of the invention,
(A) A thin film in the first region of the substrate whose surface is divided into a first region including an edge of a thin film pattern to be formed and a second region where a solid thin film is formed. Attaching a photocurable thin film material to the region to be formed;
(B) after the step a, irradiating the thin film material attached to the first region of the substrate with light to cure the thin film material;
(C) depositing the thin film material in the second region;
(D) after the step c, irradiating the thin film material adhering to the second region substrate with light to cure the thin film material, and after adhering to the second region, There is provided a thin film forming method in which the time until the thin film material is irradiated with light in the step d is longer than the time until the thin film material is irradiated with light in the step b after being attached to the first region.

According to yet another aspect of the invention,
A stage for holding a substrate;
Opposite the substrate held on the stage, the surface of the substrate is irradiated with a plurality of nozzle holes for discharging droplets of a photocurable thin film material, and the thin film material attached to the substrate is irradiated with curing light. A nozzle unit provided with a light source;
A moving mechanism for moving one of the nozzle unit and the stage relative to the other in a direction parallel to the surface of the substrate;
A control device storing image data of a thin film pattern to be formed on the substrate,
The controller is
Based on the image data, after the droplet of the thin film material has landed on the edge of the thin film pattern, the thin film material landed on the edge is irradiated with light from the light source to form an edge pattern, and then the thin film The moving mechanism, so that a droplet of the thin film material has landed inside a region for forming a pattern, and the thin film material landed inside the region for forming the thin film is irradiated with light from the light source, A thin film forming apparatus for controlling the nozzle unit and the light source is provided.

According to yet another aspect of the invention,
A stage for holding a substrate;
A nozzle unit provided with a plurality of nozzle holes for discharging a liquid material having photocurability and insulation toward the substrate held on the stage and attaching the liquid material to the substrate;
A moving mechanism for moving one of the stage and the nozzle unit in the Y direction parallel to the surface of the substrate with respect to the other;
A first light source that is disposed away from the plurality of nozzle holes in the Y direction and cures the liquid material by irradiating the liquid material attached to the substrate with light;
A second light source that is disposed further away from the first light source in the Y direction from the plurality of nozzle holes and that cures the liquid material by irradiating the liquid material attached to the substrate with light;
A controller that stores image data defining a thin film pattern to be formed on the surface of the substrate, and controls the moving mechanism, the nozzle unit, and the first and second light sources based on the image data;
With
In the control device, the first light source cures the liquid material adhering to the first region including the edge of the thin film pattern, and the second light source forms the second region where the thin film pattern is solid. There is provided a thin film forming apparatus for controlling the first and second light sources so as to cure the liquid material adhered to the substrate.

  After the thin film material that has landed on the edge of the thin film pattern is cured, when the droplet of the thin film material is landed on the area corresponding to the inside of the thin film pattern, the already cured thin film material is in the in-plane direction of the thin film material. To block the flow of water. For this reason, it is not necessary to immediately cure the thin film material that has landed on the region corresponding to the inside of the thin film pattern. The thin film material can be cured after spreading in the in-plane direction. Thereby, the surface inside a thin film pattern can be made flat.

1 is a side view of a thin film forming apparatus according to a first embodiment. 2A is a perspective view of a nozzle unit used in the thin film forming apparatus according to Embodiment 1, and FIG. 2B is a bottom view of the nozzle unit. FIG. 3 is a plan view of a substrate having a thin film pattern formed by the thin film forming method according to the first embodiment and a nozzle unit. 4A is a plan view of the substrate and the nozzle unit before and after the first scan of the thin film formation method according to Example 1, FIG. 4B is a cross-sectional view taken along the dashed-dotted line 4B-4B in FIG. 4A, and FIG. FIG. 4D is a plan view of the substrate and the nozzle unit before and after the second scan of the thin film forming method according to the first embodiment, and FIG. 4D is a cross-sectional view taken along one-dot chain line 4D-4D in FIG. 4C. 4E is a plan view of the substrate and the nozzle unit before and after the third scan of the thin film formation method according to Example 1, FIG. 4F is a cross-sectional view taken along one-dot chain line 4F-4F in FIG. 4E, and FIG. FIG. 4 is a plan view of the substrate and the nozzle unit before and after the fourth scan of the thin film forming method according to Example 1, and FIG. 4H is a cross-sectional view taken along one-dot chain line 4H-4H in FIG. 4G. 4I is a plan view of the substrate and the nozzle unit before and after the fifth scan of the thin film formation method according to Example 1, FIG. 4J is a cross-sectional view taken along one-dot chain line 4J-4J in FIG. 4I, and FIG. FIG. 4L is a plan view of the substrate and the nozzle unit before and after the sixth scan of the thin film forming method according to Example 1, and FIG. 4L is a cross-sectional view taken along the alternate long and short dash line 4L-4L in FIG. 4K. 5A, FIG. 5B, and FIG. 5C are cross-sectional views taken along one-dot chain line 5A-5A in FIG. 4A, cross-sectional views along one-dot chain line 5B-5B in FIG. 4E, and cross-sectional views along one-dot chain line 5C-5C in FIG. 6A and 6B are cross-sectional views of thin film patterns formed by the method according to Comparative Example and Example 1, respectively. 7A is a plan view of the substrate and the nozzle unit before and after the second scanning of the thin film forming method according to the second embodiment. FIG. 7B is a plan view of the substrate and the nozzle unit before and after the third scanning of the thin film forming method according to the second embodiment. It is a top view of a nozzle unit. 7C is a plan view of the substrate and the nozzle unit before and after the fourth scan of the thin film forming method according to the second embodiment. FIG. 7D is a plan view of the substrate and the nozzle unit before and after the fifth scan of the thin film forming method according to the second embodiment. It is a top view of a nozzle unit. FIG. 7E is a plan view of the substrate and the nozzle unit before and after the sixth scan of the thin film formation method according to the second embodiment. 8A is a plan view of the substrate and the nozzle unit before and after the first scanning of the thin film forming method according to Example 3, and FIG. 8B is a plan view of the substrate and the nozzle before and after the second scanning of the thin film forming method according to Example 3. It is a top view of a nozzle unit. FIG. 8C is a plan view of the substrate and the nozzle unit before and after the third scan of the thin film formation method according to Example 3, and FIG. 8D shows the substrate and the nozzle unit before and after the fourth scan of the thin film formation method according to Example 3. It is a top view of a nozzle unit. FIG. 9 is a plan view of the nozzle unit of the thin film forming apparatus according to the fourth embodiment. FIG. 10A is a plan view of the substrate and the nozzle unit before and after the first scan of the thin film formation method according to the fourth embodiment. FIG. 10B is a plan view of the substrate and the nozzle unit before and after the second scanning of the thin film forming method according to the fourth embodiment. FIG. 10C is a plan view of the substrate and the nozzle unit before and after the third scan of the thin film forming method according to the fourth embodiment. FIG. 11 is a bottom view of the nozzle unit used in the evaluation experiment of Example 5. FIG. FIG. 12 is a partial side view of the thin film forming apparatus according to the fifth embodiment. 13A is a plan view of a thin film pattern and a nozzle unit formed on a substrate, and FIGS. 13B and 13C are cross-sectional views taken along one-dot chain line 13-13 in FIG. 13A. FIG. 14 is a bottom view of the nozzle unit according to the fifth embodiment. 15A and 15B are side views of the nozzle unit and the substrate when the thin film pattern is formed by the method according to the fifth embodiment. 16A is a plan view of a thin film pattern and a nozzle unit formed on a substrate by the method according to Example 5, and FIG. 16B is a cross-sectional view taken along one-dot chain line 16B-16B in FIG. 16A. 17A and 17B are plan views of a nozzle unit and a substrate according to a modification of the fifth embodiment. 18A and 18B are side views of the nozzle unit and the substrate when a thin film pattern is formed by the method according to Example 6, and FIG. 18C is a thin film pattern formed by the method according to a modification of Example 6. It is a side view of a nozzle unit and a board | substrate when doing. 19A is a plan view of a thin film pattern and a nozzle unit formed on a substrate by the method according to Example 6, and FIG. 19B is a cross-sectional view taken along one-dot chain line 19B-19B in FIG. 19A. FIG. 20 is a plan view of a thin film pattern formed by a method according to a modification of Example 6 and a nozzle unit. 21A to 21D are cross-sectional views of a semiconductor device manufactured by the method according to Example 7 in the middle of manufacturing. 22A and 22B are bottom views showing the arrangement of the nozzle heads of the thin film forming apparatus according to the eighth embodiment and its modification, respectively. FIG. 23 is a bottom view showing the arrangement of the nozzle head of the thin film forming apparatus according to the ninth embodiment. 24A, FIG. 24B, FIG. 24C, and FIG. 24D show edge patterns after the first, second, third, and fourth scans, respectively, when forming a thin edge pattern using the thin film forming apparatus according to Example 9. It is a top view which shows the pixel which thin film material landed.

  [Example 1]

  FIG. 1 shows a schematic view of a thin film forming apparatus according to the first embodiment. A stage 22 is supported on the surface plate 20 by a moving mechanism 21. A substrate 50 such as a printed wiring board is held on the upper surface (holding surface) of the stage 22. An XYZ orthogonal coordinate system is defined in which the directions parallel to the holding surface of the stage 22 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 22 in the X direction and the Y direction.

  A beam 32 is supported by a column 31 above the surface plate 20. A nozzle unit support mechanism 29 and an imaging device 30 are attached to the beam 32. The nozzle unit 23 is supported by the nozzle unit support mechanism 29. The imaging device 30 and the nozzle unit 23 face the substrate 50 held on the stage 22. The imaging device 30 images a wiring pattern, an alignment mark, a thin film pattern formed on the substrate 50, and the like formed on the surface of the substrate 50. Image data obtained by imaging is input to the control device 40. The nozzle unit 23 ejects droplets of a photocurable (for example, ultraviolet curable) thin film material, for example, a droplet of a solder resist or the like, toward the substrate 50 from a plurality of nozzle holes. The discharged thin film material adheres to the surface of the substrate 50.

  Instead of fixing the nozzle unit 23 to the surface plate 20 and moving the stage 22, the nozzle unit 23 may be moved relative to the stage 22 and the surface plate 20.

  The control device 40 controls the moving mechanism 21, the nozzle unit 23, and the imaging device 30. The controller 40 stores raster format image data that defines a thin film pattern to be formed on the substrate 50. An operator inputs various commands (commands) and numerical data necessary for control to the control device 40 through the input device 41. As the input device 41, for example, a keyboard, a touch panel, a pointing device, or the like is used. The control device 40 outputs various information from the output device 42 to the operator. A liquid crystal display or the like is used for the output device 42.

  FIG. 2A shows a perspective view of the nozzle unit 23. A plurality of, for example, four nozzle heads 24 are attached to the nozzle holder 26. A plurality of nozzle holes 24 a are formed in each nozzle head 24. The nozzle holes 24a are arranged in the X direction, and the four nozzle heads 24 are fixed to the nozzle holder 26 side by side in the Y direction.

  Between the nozzle heads 24, ultraviolet light sources 25 are respectively arranged outside the nozzle heads 24 at both ends. The ultraviolet light source 25 irradiates the substrate 50 (FIG. 1) with ultraviolet rays. In addition, when using the material which hardens | cures with the component of light outside the wavelength range of an ultraviolet-ray as a thin film material, it replaces with the ultraviolet light source 25, and the light source which radiates | emits the light containing the wavelength component which can harden a thin film material is used. Used.

  FIG. 2B shows a bottom view of the nozzle head 24 and the ultraviolet light source 25. Two rows of nozzle rows 24 b are arranged on the bottom surface (surface facing the substrate 50) of each nozzle head 24. Each of the nozzle rows 24b includes a plurality of nozzle holes 24a arranged at a pitch (period) 8P in the X direction. One nozzle row 24b is displaced in the Y direction with respect to the other nozzle row 24b, and is further displaced by a pitch 4P in the X direction. That is, paying attention to one nozzle head 24, the nozzle holes 24a are distributed at equal intervals with a pitch of 4P in the X direction. The pitch 4P corresponds to a resolution of 300 dpi, for example.

  The four nozzle heads 24 are arranged in the Y direction and are displaced from each other in the X direction and attached to the nozzle holder 26 (FIG. 2A). In FIG. 2B, with the leftmost nozzle head 24 as a reference, the second, third, and fourth nozzle heads 24 are respectively shifted by 2P, P, and 3P in the negative direction of the X axis. For this reason, when attention is paid to the four nozzle heads 24 (as a whole nozzle head), the nozzle holes 24a are arranged at equal intervals in the X direction at a pitch P (pitch corresponding to 1200 dpi).

  Ultraviolet light sources 25 are arranged between the nozzle heads 24 and further outside the outermost nozzle head 24 in the Y direction. The ultraviolet light source 25 cures the liquid thin film material attached to the substrate 50 (FIG. 1).

  A thin film pattern can be formed with a resolution of 1200 dpi in the X direction by discharging droplets of a thin film material from each nozzle hole 24a of the nozzle unit 23 while moving the substrate 50 (FIG. 1) in the Y direction. By performing the scanning twice while shifting by P / 2 in the X direction, the resolution in the X direction can be doubled to 2400 dpi. The two scans can be realized by a reciprocating scan in which the directions of the first scan and the second scan are reversed. The resolution in the Y direction is determined by the moving speed of the substrate 30 and the discharge period of droplets from the nozzle holes 24a.

  FIG. 3 is a plan view of the substrate 50 on which the thin film pattern is formed and the nozzle unit 23. A thin film pattern 55 is formed on the surface of the substrate 50. The board 50 is a multi-sided board in which a plurality of printed wiring boards are arranged in the plane. As an example, printed wiring boards are arranged in a matrix of 4 rows and 2 columns in the plane of the substrate 50. A thin film pattern 55 is defined corresponding to the printed wiring board. The thin film pattern 55 is formed of, for example, a solder resist.

  The operation of ejecting droplets of the thin film material from the nozzle unit 23 while moving the substrate 50 in the Y direction is referred to as “scanning”. An area where a thin film material droplet can be landed by one scan is referred to as a unit scan area 56. The dimension (width) in the X direction of the unit scanning region 56 is represented by W. As an example, the width W of the unit scanning region 56 is ¼ of the dimension in the X direction of the substrate 50.

  With reference to FIGS. 4A to 4L and FIGS. 5A to 5C, the thin film forming method according to the first embodiment will be described. 4A to 4L, only the region corresponding to one printed wiring board is shown as a representative of the substrate 50 shown in FIG. Further, for convenience of explanation, two squares and four circular openings are arranged in the thin film pattern, but actually, a lot of finer openings are arranged.

  FIG. 4A shows a plan view of the substrate 50 and the nozzle unit 23 before and after the first scan. FIG. 4B is a cross-sectional view taken along one-dot chain line 4B-4B in FIG. 4A. FIG. 5A is a cross-sectional view taken along one-dot chain line 5A-5A in FIG. 4A.

  As shown in FIG. 4A, the substrate 50 is scanned in the negative direction of the Y axis. At this time, droplets of the thin film material are landed from the nozzle head 24 (FIG. 5A) on the outermost peripheral edge of the thin film pattern 55 and the edge of the opening. During scanning, the substrate 50 is irradiated with ultraviolet rays from the ultraviolet light source 25 (FIG. 5A). For this reason, the surface layer portion of the thin film material is cured immediately after the droplet of the thin film material has landed on the substrate 50. Since the ultraviolet light emitted from the ultraviolet light source 25 does not have sufficient light energy density on the substrate surface, the inside of the thin film material is in an uncured state. A reaction in which only the surface layer portion of the thin film material is cured is referred to as “temporary curing”, and a reaction that cures to the inside is referred to as “main curing”. By the first scanning, a linear edge pattern 60 made of a temporarily cured thin film material is formed at the outermost peripheral edge of the thin film pattern and the edge of the opening in one unit scanning region 56 (FIG. 3). The

  FIG. 4C shows a plan view of the substrate 50 and the nozzle unit 23 before and after the second scan. FIG. 4D is a cross-sectional view taken along one-dot chain line 4D-4D in FIG. 4C. As shown in FIG. 4C, the substrate 50 is moved in the negative direction of the X axis by a distance equal to the width W of the unit scanning region 56. Thereafter, the substrate 50 is moved in the positive direction of the Y axis to perform the second scan. Also in the second scan, the droplet of the thin film material is landed from the nozzle unit 23 to the outermost peripheral edge of the thin film pattern 55 and the edge of the opening, and the thin film material is temporarily cured immediately after the landing.

  A pre-cured edge pattern 61 is formed at the outermost peripheral edge of the thin film pattern 55 and the edge of the opening in the unit scanning region 56 adjacent to the unit scanning region 56 where the edge pattern 60 is formed by the first scanning. Is done.

  FIG. 4E shows a plan view of the substrate 50 and the nozzle unit 23 before and after the third scan. 4F shows a cross-sectional view taken along one-dot chain line 4F-4F in FIG. 4E, and FIG. 5B shows a cross-sectional view taken along one-dot chain line 5B-5B in FIG. 4E. After the second scan is completed, the substrate 50 is moved in the negative direction of the Y axis to perform the third scan. In the third scan, a droplet of the thin film material is landed from the nozzle head 24 (FIG. 5B) to the inside (solid region) of the region where the thin film pattern 55 (FIG. 3) is formed. A planar pattern 62 having the edge pattern 61 formed by the second scanning as an edge is formed. In the third scan, the ultraviolet light source 25 (FIG. 5B) is in the extinguished state. For this reason, the planar pattern 62 remains uncured.

  Although the planar pattern 62 is uncured, the edge pattern 61 formed in a region corresponding to the edge of the thin film pattern 55 blocks the spread of the thin film material in the in-plane direction. For this reason, the uncured thin film material does not enter the inside of the opening. At the boundary line 63 of the unit scanning region 56 (FIG. 3), an edge pattern for blocking the uncured thin film material is not formed. For this reason, on the boundary line 63 of the unit scanning region 56, the thin film material spreads until reaching an equilibrium state based on wettability with the substrate.

  FIG. 4G shows a plan view of the substrate 50 and the nozzle unit 23 before and after the fourth scan. FIG. 4H is a cross-sectional view taken along one-dot chain line 4H-4H in FIG. 4G. After the third scan, the substrate 50 is moved in the positive direction of the X axis by a distance equal to the width W of the unit scan region 56 (FIG. 3). In this state, the substrate 50 is moved in the positive direction of the Y axis to perform the fourth scan. In the fourth scan, as in the third scan, droplets of the thin film material are landed inside the region where the thin film pattern 55 (FIG. 3) is formed. A planar pattern 64 having the edge pattern 60 formed by the first scan as an edge is formed. Even in the fourth scan, the ultraviolet light source 25 (FIG. 5B) is in the off state. For this reason, the planar pattern 64 remains uncured.

  Since the planar pattern 62 formed by the third scan and the planar pattern 64 formed by the fourth scan are both uncured, the thin film materials are mixed in the vicinity of the boundary line between them. For this reason, the boundary line 63 of the unit scanning region 56 is hardly visible.

  FIG. 4I shows a plan view of the substrate 50 and the nozzle unit 23 before and after the fifth scan. 4J is a cross-sectional view taken along one-dot chain line 4J-4J in FIG. 4I. FIG. 5C is a cross-sectional view taken along one-dot chain line 5C-5C in FIG. 4I. After the fourth scan, the fifth scan is performed by moving the substrate 50 in the negative direction of the Y-axis. In the fifth scan, only the ultraviolet light source 25 irradiates ultraviolet rays without discharging the thin film material droplets from the nozzle head 24 (FIG. 5C). The uncured planar pattern 64 is temporarily cured by ultraviolet irradiation. In FIG. 4I, the pre-cured region is densely hatched, and the uncured region is sparsely hatched. The same applies to other drawings shown later.

  FIG. 4K shows a plan view of the substrate 50 and the nozzle unit 23 before and after the sixth scan. FIG. 4L is a cross-sectional view taken along one-dot chain line 4L-4L in FIG. 4K. After the fifth scan, the substrate 50 is moved in the negative direction of the X axis by a distance equal to the width W of the unit scan region 56 (FIG. 3). In this state, the substrate 50 is moved in the positive direction of the Y axis to perform the sixth scan. Even in the sixth scan, the thin film material droplets are not ejected from the nozzle head 24 (FIG. 5C), and only the ultraviolet light irradiation by the ultraviolet light source 25 is performed. The uncured planar pattern 62 is temporarily cured by ultraviolet irradiation.

  With reference to FIG. 6A and FIG. 6B, the effect of the thin film formation method by Example 1 is demonstrated. 6A and 6B are sectional views of thin film patterns formed by the method according to the comparative example and Example 1, respectively.

  In the comparative example shown in FIG. 6A, the thin film pattern was formed without distinguishing the edge and the inside of the thin film pattern 55 (FIG. 3). When scanning the substrate 50, the ultraviolet light source 25 (FIGS. 2A and 2B) was turned on, and the thin film material was temporarily cured immediately after the thin film material landed. As shown in FIGS. 2A and 2B, the ultraviolet light source 25 is disposed between the nozzle heads 24. Therefore, after a thin film material droplet discharged from one nozzle head 24 has landed on the substrate 50, before a thin film material droplet discharged from the next nozzle head 24 landed on the substrate 50, first, The landing thin film material is temporarily cured.

  Therefore, the thin film material droplets 55a discharged from the nozzle holes 24a (FIGS. 2A and 2B) overlap each other in a distinguishable state. Concavities and convexities are formed on the surface of the thin film pattern 55 corresponding to each of the droplets 55a. This unevenness is visually recognized as a striped pattern extending in the Y direction.

  As shown in FIG. 6B, in the method according to the first embodiment, edge patterns 60 and 61 are formed on the edge of the thin film pattern 55, and planar patterns 62 and 64 are formed inside the thin film pattern 55. As in the case of FIG. 6A, the thin film materials constituting the edge patterns 60 and 61 overlap in a state where the droplets 55a are distinguishable. That is, other droplets land on the thin film material that has landed on the substrate 50 and is temporarily cured, and are temporarily cured. For this reason, edge patterns 60 and 61 higher than the height of the thin film material formed by temporarily curing one droplet are obtained. However, the planar patterns 62 and 64 are temporarily cured (FIGS. 4I and 4K) after a plurality of droplets of the thin film material spread in the in-plane direction of the substrate to form a film having a substantially uniform thickness (FIG. 4G). Is done. For this reason, the surface of the planar patterns 62 and 64 becomes substantially flat.

  In order to flatten the surfaces of the planar patterns 62 and 64, the thin film material that has landed on the substrate in the step of FIG. 4E spreads in the in-plane direction of the substrate, and the thin film materials that have landed on a plurality of landing points are continuous. After adjacent landing points cannot be distinguished, it is preferable to harden the thin film material of the planar pattern 62 in the process of FIG. 4K.

  In the first embodiment, as shown in FIGS. 4A and 4B, the edge pattern 60 is formed in a region corresponding to the edge of the thin film pattern 55 in one unit scanning region 56 (FIG. 3) by one-way scanning. , 61 was formed. The resolution in the X direction can be doubled by shifting in the X direction by a distance corresponding to ½ of the pitch P (FIG. 2B) and reciprocating scanning.

  In the step of forming the planar pattern 62 shown in FIG. 4E and the step of forming the planar pattern 64 shown in FIG. 4G, all pixels in the solid area of the raster format image data defining the thin film pattern 55 are formed. It is not necessary to land the droplets of the thin film material. As an example, the array pitch of pixels is about 10 μm, and the diameter of a circular pattern formed by droplets that land on one pixel is about 50 μm. For this reason, the landing points may be extracted by thinning out pixels in the solid area. That is, the distribution density of the landing points when the planar patterns 62 and 64 are formed may be lower than the distribution density of the landing points when the edge patterns 60 and 61 are formed. Further, the distribution density of the landing points when the planar patterns 62 and 64 are formed may be lowered, and the volume of droplets per discharge from the nozzle holes 24a (FIG. 2A) may be increased. By increasing the volume of the droplets, the planar patterns 62 and 64 can have a desired thickness even if the distribution density of the landing points is lowered.

[Example 2]
Next, a thin film forming method according to Example 2 will be described with reference to FIGS. Hereinafter, differences from the first embodiment will be described, and description of the same configuration will be omitted. The edge pattern 60 shown in FIG. 4A of the first embodiment is formed by the first scanning.

  FIG. 7A shows a plan view of the substrate 50 and the nozzle unit 23 before and after the second scan. After the first scan, the second scan is performed by moving the substrate 50 in the positive direction of the Y-axis. In the second scanning, an uncured planar pattern 64 is formed in the same unit scanning region 56 as the unit scanning region 56 (FIG. 3) where the edge pattern 60 is formed.

  FIG. 7B shows a plan view of the substrate 50 and the nozzle unit 23 before and after the third scan. After the second scan, the third scan is performed by moving the substrate 50 in the negative direction of the Y axis without shifting in the X direction. In the third scan, only the ultraviolet light from the ultraviolet light source 25 (FIGS. 2A and 2B) is irradiated without discharging a thin film material droplet from the nozzle unit 23. Thereby, the planar pattern 64 is temporarily cured.

  FIG. 7C shows a plan view of the substrate 50 and the nozzle unit 23 before and after the fourth scan. After the third scan, the substrate 50 is shifted in the negative direction of the X axis by a distance equal to the width W of the unit scan region 56 (FIG. 3). Thereafter, the substrate 50 is moved in the positive direction of the Y axis to perform the fourth scan. In the fourth scan, in the unit scan region 56 adjacent to the unit scan region 56 (FIG. 3) in which the edge pattern 60 and the planar pattern 64 are formed in the first to third scans, the edge of the thin film pattern 55 is formed. A corresponding edge pattern 61 is formed. The edge pattern 61 is temporarily cured during the fourth scan.

  As shown in FIG. 7D, an uncured planar pattern 62 is formed by performing the fifth scan. As shown in FIG. 7E, the planar pattern 62 is temporarily cured by performing the sixth scan. 7D and 7E are the same as the process of forming the planar pattern 64 shown in FIGS. 7A and 7B.

  In Example 1, after forming the edge patterns 60 and 61 in the part corresponding to the edge of the thin film pattern 55 (FIG. 3) (FIGS. 4A to 4D), the planar patterns 62 and 64 are formed (FIGS. 4E to 4E). FIG. 4L). In the second embodiment, after the edge pattern and the planar pattern in one unit scanning region 56 (FIG. 3) are formed, the edge pattern and the planar pattern in the adjacent unit scanning region 56 are formed. Also in the second embodiment, the surfaces of the planar patterns 62 and 64 are flat as in the first embodiment.

  In Example 2, after the planar pattern 64 (FIG. 7B) is temporarily cured, the planar pattern 62 (FIG. 7D) in the adjacent unit scanning region 56 is formed. For this reason, the boundary line 63 (FIG. 7E) of the unit scanning region 56 becomes easier to visually recognize than the first embodiment. However, many striped patterns corresponding to the number of nozzle holes 24a are not visually recognized.

[Example 3]
With reference to FIGS. 8A to 8D, a thin film forming method according to Example 3 will be described. Hereinafter, differences from the second embodiment will be described, and description of the same configuration will be omitted. The nozzle unit 23 (FIG. 2A) of the thin film forming apparatus used in Example 2 included four nozzle heads 24. The nozzle unit 23 of the thin film forming apparatus used in the third embodiment includes eight nozzle heads 24.

  FIG. 8A shows a plan view of the substrate 50 before and after the first scan, and the nozzle unit 23. The nozzle unit 23 includes two subunits 23A and 23B. The configuration of each of the subunits 23A and 23B is the same as that of the nozzle unit 23 (FIG. 2A) of the first embodiment. The subunits 23a and 23B are arranged in the Y direction at a certain interval. The subunit 23A is arranged on the positive side of the Y axis with respect to the subunit 23B.

  The first scan is performed by moving the substrate 50 in the negative direction of the Y axis. In the first scan, the edge pattern 60 is formed using the subunit 23A. The ultraviolet light source 25 of the subunit 23A is turned on. For this reason, the formed edge pattern 60 will be in the state of temporary hardening.

  During the first scan, the planar pattern 64 is further formed using the subunit 23B. The ultraviolet light source 25 of the subunit 23B is turned off. For this reason, the formed planar pattern 64 is in an uncured state. After the edge pattern 60 is temporarily cured, a thin film material for forming the planar pattern 64 is discharged from the subunit 23B. Since the edge pattern 60 blocks the thin film material discharged from the subunit 23B, the thin film material does not enter the opening.

  FIG. 8B shows a plan view of the substrate 50 and the nozzle unit 23 before and after the second scan. After the first scan, the second scan is performed by moving the substrate 50 in the positive direction of the Y axis without shifting in the X direction. In the second scan, at least one ultraviolet light source 25 of the subunits 23A and 23B is turned on. Thereby, the planar pattern 64 is temporarily cured.

  As shown in FIG. 8C, after the second scan, the substrate 50 is moved in the negative direction of the X axis by a distance equal to the width W of the unit scan region 56 (FIG. 3). By performing the third scan in this state, a temporarily cured edge pattern 61 and an uncured planar pattern 62 are formed. The third scan is the same as the first scan shown in FIG. 8A.

  As shown in FIG. 8D, the fourth scan is performed in the same manner as the second scan shown in FIG. 8B. The planar pattern 62 is temporarily cured by the fourth scan.

  In Example 2, a thin film pattern was formed in one unit scan region 56 (FIG. 3) by three scans. In Example 3, a thin film pattern can be formed in one unit scanning region 56 (FIG. 3) by performing scanning twice.

[Example 4]
With reference to FIG. 9 and FIGS. 10A to 10C, a thin film forming method according to Example 4 will be described. Hereinafter, differences from the third embodiment will be described, and description of the same configuration will be omitted.

  In FIG. 9, the top view of the nozzle unit 23 of the thin film forming apparatus by Example 4 is shown. The nozzle unit 23 includes two subunits 23A and 23B. Each of the subunits 23A and 23B is attached to the same nozzle holder 23 and has the same configuration as the nozzle unit 23 (FIGS. 2A and 2B) of the first embodiment. That is, each of the subunits 23 </ b> A and 23 </ b> B includes four nozzle heads 24 and five ultraviolet light sources 25. The two subunits 23A and 23B are arranged at the same position in the X direction. The subunit 23A is disposed closer to the positive side of the Y axis than the subunit 23B.

  Further, the nozzle unit 23 of the fourth embodiment includes two solid region ultraviolet light sources 70. Each of the solid region ultraviolet light sources 70 has a shape that is long in the X direction, and is 1 / of the width W of the unit scanning region 56 (FIG. 3) in the negative direction of the X axis with respect to the subunits 23A and 23B. It is fixed at a position shifted by a distance equal to 2. Regarding the Y direction, two solid region ultraviolet light sources 70 are arranged so as to sandwich two subunits 23A and 23B.

  FIG. 10A shows a plan view of the substrate 50 and the nozzle unit 23 before and after the first scan. The subunits 23A and 23B are arranged at positions corresponding to the unit scanning region 56 that is the most negative in the X direction. The first scan is performed by moving the substrate 50 in the negative direction of the Y axis.

  In the first scan, the edge pattern 60 is formed by operating the nozzle head 24 and the ultraviolet light source 25 of the subunit 23A. At the same time, the nozzle head 24 of the subunit 23B is operated to form the planar pattern 64. Further, by turning on the solid region ultraviolet light source 70 arranged on the negative side of the Y-axis, the half region on the negative side in the X direction of the planar pattern 64 is temporarily cured. The thin film material droplets discharged from the nozzle head 24 of the subunit 23B are temporarily cured by the solid region ultraviolet light source 70 until the thin film material droplets adhering to the substrate spread in the in-plane direction. This is longer than the time required for the planar pattern 64 to have a uniform film thickness. For this reason, the surface of the temporarily cured portion of the planar pattern 64 becomes substantially flat. The time from the adhesion of the thin film material to the temporary curing can be controlled by adjusting the interval between the subunit 23B and the solid region ultraviolet light source 70 on the Y direction negative side.

  FIG. 10B shows a plan view of the substrate 50 and the nozzle unit 23 before and after the second scan. After the first scan, the substrate 50 is moved in the negative direction of the X axis by a distance equal to the width W of the unit scan region 56. In this state, the second scan is performed by moving the substrate 50 in the positive direction of the Y axis. In the second scan, the edge pattern 61 is formed by operating the nozzle head 24 and the ultraviolet light source 25 of the subunit 23B. The surface pattern 62 is formed by operating the nozzle head 24 of the subunit 23A. Further, by turning on the solid region ultraviolet light source 70 arranged on the positive side in the Y direction, the uncured portion of the planar pattern 64 and a portion on the negative side in the X direction of the planar pattern 62 are temporarily cured. .

  FIG. 10C shows a plan view of the substrate 50 and the nozzle unit 23 before and after the third scan. After the second scan, the substrate 50 is moved in the negative direction of the X axis by a distance equal to the width W of the unit scan region 56. In this state, a third scan is performed by moving the substrate 50 in the negative direction of the Y axis. The third scan is performed in the same procedure as the first scan. Thereby, the edge pattern 65 and the planar pattern 66 are formed in the unit scanning region 56 adjacent to the X direction positive side with respect to the unit scanning region 56 in which the thin film pattern is formed by the second scanning. At this time, the uncured portion of the planar pattern 62 is temporarily cured by the ultraviolet rays from the solid region ultraviolet light source 70, and the X-direction negative side portion of the planar pattern 66 is temporarily cured. By repeating the same scanning, a thin film pattern can be formed over the entire area of the substrate 50.

  In Example 4, the formation of the edge pattern, the formation of the planar pattern, and the temporary curing of a part of the planar pattern are performed by one scan. Therefore, it is possible to form a thin film pattern with a smaller number of scans than in the third embodiment.

  In Example 4, when attention is paid only to the area (solid area) inside the thin film pattern 55 (FIG. 3), the following steps are executed in order.

  First, while moving the substrate 50 in the Y direction, a droplet of a thin film material is landed in the first unit scanning region 56 having the first width W in the X direction (FIG. 10A). As a result, a planar pattern 64 is formed in the first unit scanning region 56. During this scanning, the thin film material adhering to a part on the negative side in the X direction in the first unit scanning region 56 is temporarily cured.

  Thereafter, while moving the substrate 50 in the Y direction, a droplet of the thin film material is landed in the second unit scanning region 56 adjacent to the first unit scanning region on the positive side in the X direction (FIG. 10B). As a result, a planar pattern 62 is formed in the second unit scanning region 56. During this scanning, the thin film material adhering to the uncured portion on the X direction positive side in the first unit scanning region 56 and the portion on the negative side in the X direction in the second unit scanning region 56 is temporarily cured. .

  As described above, only a part of the planar patterns 64 and 62 is temporarily cured in one scan. Since the thin film material adheres to the temporarily cured region and the region that remains uncured by the same scanning, the boundary line between the two can be made inconspicuous. In FIG. 10B, the region on the positive side in the X direction of the planar pattern 64 is not temporarily cured at the stage where the thin film material for forming the planar pattern 62 is attached to the substrate 50. For this reason, the thin film materials are mixed with each other in the vicinity of the boundary line between the planar pattern 64 and the planar pattern 62. For this reason, the boundary line between the planar pattern 62 and the planar pattern 64 can be made inconspicuous.

[Example 5]
With reference to FIGS. 11-17B, the thin film formation method by Example 5 is demonstrated. Hereinafter, differences from the first embodiment will be described, and description of the same configuration will be omitted. Before describing Example 5, an evaluation experiment will be described.

  FIG. 11 shows a bottom view of the nozzle unit used in the evaluation experiment. The nozzle unit 23R includes a nozzle head 24, a light source 25, and a nozzle holder (support mechanism) 26 that supports them. The nozzle head 24 is provided with a plurality of nozzle holes 24a that are regularly arranged and discharge solder resist. Each of the nozzle holes 24a includes, for example, a piezo element, and discharges a solder resist in response to application of a voltage pulse. The discharge of the solder resist from the nozzle hole 24a is controlled by the control device 40. The light sources 25 are arranged on both sides along the arrangement direction of the nozzle holes 24a. An interval between the light source 25 and the nozzle hole 24a is represented by L. The light source 25 photocures the solder resist discharged from the nozzle holes 24a and attached to the substrate. The light source 25 is provided with an optical system in which the emitted light becomes parallel light. The light source 25 arranged on the positive side of the Y axis with respect to the nozzle head 24 photocures the solder resist attached to the substrate 50 (FIG. 1) when the substrate is scanned in the positive direction of the Y axis. The light source 25 disposed on the negative side of the Y axis with respect to the nozzle head 24 photocures the solder resist attached to the substrate when the substrate 50 is scanned in the negative direction of the Y axis. Therefore, the light source 25 may be arranged only on one side of the array of nozzle holes 24a depending on the substrate scanning method.

  FIG. 12 shows a side view when the substrate 50 is scanned. The control device 40 (FIG. 1) moves the substrate 50 with respect to the nozzle unit 23R at a constant feed rate, for example, in the negative direction of the Y axis. Furthermore, the control device 40 applies a voltage pulse to the nozzle holes 24a at a predetermined cycle based on image data stored in advance, and discharges the solder resist from the nozzle holes 24a. The nozzle hole 24a discharges the solder resist toward the surface of the substrate 50 vertically below the nozzle hole 24a by applying a voltage pulse starting at time T1. The droplets of the solder resist discharged from the nozzle holes 24a gradually spread in the in-plane direction of the substrate 50 after landing on the substrate 50. The solder resist that adheres to the substrate 50 and spreads in the in-plane direction moves in the negative direction of the Y axis as the substrate 50 moves. The solder resist is cured by light irradiation from the light source 25 at a time T2 when the light source 25 moves vertically below the nozzle hole 24a by a distance L. This discharging and curing process is repeated to form a thin film pattern made of a solder resist on the surface of the substrate 50.

  FIG. 13A shows a plan view of a thin film pattern to be formed on the substrate 50. The thin film pattern to be formed on the substrate 50 includes an insulating region 51 where a solder resist is formed, and a land region 52 where a solder resist is not formed. Further, a fine region 50 a where the land regions 52 are densely packed and a solid region 50 b whose entire surface is covered with the insulating region 51 are included. In the drawing, the insulating region 51 is hatched. The control device 40 (FIG. 1) discharges the solder resist from the nozzle holes 24a while moving the substrate 50 with respect to the nozzle unit 23R based on the image data of the thin film pattern. By curing the solder resist attached to the substrate 50 by light irradiation from the light source 25, a thin film pattern made of the solder resist is formed. The droplets of the solder resist discharged from the nozzle holes 24a gradually spread in the in-plane direction of the substrate 50 after landing on the substrate 50. When the solder resist is cured by light irradiation from the light source 25, its shape is maintained.

  13B and 13C are cross-sectional views taken along the arrow line 13-13 in FIG. 13A. When the distance L (FIG. 11) between the nozzle hole 24a of the nozzle unit 23R and the light source 25 is small, the solder resist landed on the substrate 50 is photocured at a relatively early timing. Since the solder resist that has landed on the substrate 50 is hardened before spreading greatly, it can cope with the formation of a fine thin film pattern as shown in the fine region 50a of FIG. 13B. On the other hand, the shape of the droplet remains slightly, and as shown in the solid region 50b in FIG. 13B, the film thickness of the formed thin film pattern becomes non-uniform (unevenness appears on the surface). Further, when the distance L between the nozzle hole 24a and the light source 25 is large, the solder resist that has landed on the substrate 50 is cured at a relatively late timing. Since the solder resist that has landed on the substrate 50 is hardened after spreading widely, the land region 52 is covered with the solder resist as shown in the fine region 50a of FIG. 13C, which corresponds to the formation of a fine thin film pattern. I can't. On the other hand, as shown in the solid region 50b in FIG. 13C, the film thickness of the formed thin film pattern becomes uniform (the surface becomes flat).

  When forming a thin film pattern in the fine region 50a, it is desirable to harden the solder resist landed on the substrate 50 at a relatively early timing to improve the positional accuracy of the thin film pattern. When forming a thin film pattern in the solid region 50b, it is desirable in appearance that the solder resist that has landed on the substrate 50 is cured at a relatively late timing to make the film thickness of the thin film pattern uniform.

  In FIG. 14, the bottom view of the nozzle unit by Example 5 is shown. The nozzle unit 23 according to the fifth embodiment includes a nozzle head 24, light sources 25a and 25b, and a nozzle holder (support mechanism) 26 that supports them. The nozzle head 24 is provided with a plurality of regularly arranged nozzle holes 24a. For example, the opening diameter of the nozzle holes 24a is about 30 μm, and the pitch of each nozzle hole 24a is about 80 μm. The light sources 25a and 25b are arranged on both sides along the arrangement of the nozzle holes 24a. The distance between the light source 25a and the nozzle hole 24a is represented by L1. The distance L2 between the light source 25b and the nozzle hole 24a is larger than the distance L1. For example, the distance L1 between the nozzle hole 24a and the light source 25a is about 0.3 mm, and the distance L2 between the nozzle hole 24a and the light source 25b is about 1.0 mm. The light sources 25a and 25b are provided with an optical system in which emitted light becomes parallel light. The discharge of the solder resist from the nozzle hole 24a and the on / off of the light sources 25a and 25b are controlled by the control device 40. The light sources 25a and 25b arranged on the positive side of the Y axis with respect to the nozzle head 24 are solder resists attached to the substrate 50 when the substrate 50 (FIG. 1) moves in the positive direction of the Y axis. Is cured. The light sources 25a and 25b arranged on the positive side of the Y axis with respect to the nozzle head 24 harden the solder resist attached to the substrate 50 when the substrate 50 moves in the negative direction of the Y axis. Accordingly, the light sources 25a and 25b may be arranged only on one side of the arrangement of the nozzle holes 24a according to the scanning method of the substrate 50.

  15A and 15B are side views of the nozzle unit 23 and the substrate 50 when the thin film pattern is formed by the method according to the fifth embodiment. The control device 40 (FIG. 1) moves the substrate 50 with respect to the nozzle unit 23 at a constant feed speed, for example, in the negative direction of the Y axis. Based on the image data of the thin film pattern, the control device 40 applies a voltage pulse to the nozzle holes 24a at a predetermined cycle, and discharges the solder resist from the nozzle holes 24a. For example, the feeding speed of the substrate 50 is about 300 mm / s, and the frequency at which the nozzle head 24 ejects the solder resist is about 30 kHz. The height from the substrate 50 to the nozzle head 24 is about 0.5 mm to 1 mm, and the height to the light sources 25a and 25b is about 20 mm to 30 mm. When the area where the solder resist has landed is the fine area 50a (FIG. 13A), the control device 40, as shown in FIG. 15A, emits the light from the light source 25a disposed at a position relatively close to the nozzle hole 24a. The solder resist is cured by irradiation. For example, the solder resist that has landed on the fine region 50 a is cured about 0.1 s after landing on the substrate 50. When the area where the solder resist has landed is a solid area 50a (FIG. 13A), as shown in FIG. 15B, the solder resist is irradiated with light from a light source 25b disposed at a position relatively far from the nozzle hole 24a. Is cured. For example, the solder resist that has landed on the solid region 50 b is cured about 0.3 s after landing on the substrate 50.

  FIG. 16A shows a plan view of a thin film pattern formed on the substrate 50, and FIG. 16B shows a cross-sectional view taken along arrow line 16B-16B in FIG. 16A. The thin film pattern to be drawn on the substrate 50 includes a fine region 50 a where the land regions 52 are densely packed and a solid region 50 b where the entire surface is covered with the insulating region 51. In FIG. 16A, the insulating region 51 is hatched. In the fifth embodiment, the control device 40 (FIG. 1) stores in advance the partition information of the fine region 50a and the solid region 50b of the thin film pattern to be formed. For example, the fine region 50a corresponds to a region on which an integrated circuit element (IC, LSI) having a package such as a BGA (Ball Grid Array) is mounted. The solid region 50b corresponds to a region where discrete components are mounted or a region where the entire surface is covered with a thin film pattern of solder resist. The control device 40 (FIG. 1) discharges the solder resist from the nozzle holes 24a while moving the substrate 50 with respect to the nozzle unit 23 based on the image data of the thin film pattern. Furthermore, based on the division information of the fine region 50a and the solid region 50b, the solder resist attached to the fine region 50a is cured by light irradiation from the light source 25a, and the solder resist attached to the solid region 50b is obtained from the light source 25b. Cured by light irradiation. By such a thin film pattern forming operation, as shown in FIG. 16B, the positional accuracy of the edge of the thin film pattern is improved in the fine region 50a of the substrate 50, and the film thickness of the formed thin film pattern is made uniform in the solid region 50b. It becomes possible to do. Note that the control device 40 may automatically set the fine region 50a and the solid region 50b from the image data of the thin film pattern based on the sizes of the insulating region 51 and the land region 52 and their density. .

  17A and 17B are plan views of a nozzle unit and a substrate according to a modification of the fifth embodiment. As shown in FIG. 17A, the number of light sources provided in the nozzle unit 23 is not limited to two, and may be three or more, or may be provided with a mechanism that can change the position of arrangement. Moreover, you may comprise a light source by the several light emitting diode (LED) arranged along the arrangement | sequence of a nozzle hole. The plurality of LEDs can be independently turned on / off by the control device. With such a configuration, the fine region 50a and the solid region 50b can be more finely arranged in the X-axis direction with the region irradiated with one LED as a unit region. The light source may be separated from the nozzle unit 23 and attached to the frame of the thin film forming apparatus, for example. The light source attached to the frame may be provided with a mechanism capable of changing the position where it is arranged.

  Furthermore, the nozzle head 24 provided in the nozzle unit 23 may have a configuration in which the nozzle holes 24a are arranged in a staggered manner (zigzag) as shown in FIG. 17B. The plurality of nozzle holes 24a constitute, for example, two nozzle rows 24I and 24J separated in the Y-axis direction. The nozzle holes 24a constituting each nozzle row 24I, 24J are arranged at a pitch 8P in the X-axis direction. The nozzle holes 24a constituting one nozzle row 24I are arranged so as to be shifted by 4P in the X-axis direction with respect to the nozzle holes 24a constituting the other nozzle row 24J. By configuring the nozzle head 24 in such a configuration, the resolution in the X-axis direction can be easily increased without being restricted by the supply mechanism for supplying the solder resist to the nozzle holes 24a and the dimensions and arrangement of the piezoelectric elements. Is possible.

[Example 6]
With reference to FIG. 18A-FIG. 20B, the thin film formation method by Example 6 is demonstrated. Hereinafter, differences from the fifth embodiment will be described, and description of the same configuration will be omitted.

  18A to 18C are side views of the nozzle unit 23 and the substrate 50 of the thin film forming apparatus according to the sixth embodiment. The nozzle unit 23 of the thin film forming apparatus according to the sixth embodiment includes a nozzle head 24, a light source 25, and a rotation mechanism 27 that can rotate the light source 25 around a rotation axis parallel to the X-axis direction. The rotation mechanism 27 can move the irradiation position of the light emitted from the light source 25 on the surface of the substrate 50 in the Y-axis direction by rotating the light source 25. The rotation of the light source 25 by the rotation mechanism 27 is controlled by the control device 40.

  The control device 40 moves the substrate 50 with respect to the nozzle unit 23 at a constant feed speed, for example, in the negative direction of the Y axis. Based on the stored image data, the control device 40 applies a voltage pulse to the nozzle holes 24a at a predetermined cycle, and discharges the solder resist from the nozzle holes 24a. For example, the feeding speed of the substrate 50 is about 300 mm / s, and the frequency at which the nozzle head 24 ejects the solder resist is about 30 kHz. The height from the substrate 50 to the nozzle head 24 is about 0.5 mm to 1 mm, and the height to the light source 25 is about 20 mm to 30 mm.

  When the area where the solder resist has landed is the fine area 50a (FIG. 16A), the control device 40, for example, at a position closer to the nozzle hole 24a than the vertical lower position of the light source 25, as shown in FIG. The rotation mechanism 27 is controlled so that the solder resist adhering to 50 is photocured. For example, the solder resist that has landed on the fine region 50 a is cured about 0.1 s after landing on the substrate 50. Further, when the area where the solder resist has landed is a solid area 50b (FIG. 16A), as shown in FIG. 18B, for example, at a position farther from the nozzle hole 24a than the vertical lower position of the light source 25, The rotating mechanism 27 is controlled so that the attached solder resist is cured. For example, the solder resist that has landed on the solid region 50 b is cured about 0.3 s after landing on the substrate 50.

  Note that the mechanism for moving the irradiation position of the light beam emitted from the light source 25 onto the substrate is not limited to the rotation mechanism. As shown in FIG. 18C, the irradiation position of the light beam emitted from the light source 25 onto the substrate may be moved by the optical system 28.

  FIG. 19A shows a plan view of the substrate 50 on which a thin film pattern is formed, and the nozzle unit 23. FIG. 19B shows a cross-sectional view taken along arrow line 19B-19B in FIG. 19A. As in the fifth embodiment, the thin film pattern to be formed on the substrate 50 includes a fine region 50 a where the land regions 52 are densely packed and a solid region 50 b whose entire surface is covered with the insulating region 51. In FIG. 19A, the insulating region 51 is hatched.

  The control device 40 (FIGS. 18A to 18C) discharges the solder resist from the nozzle holes 24a while moving the substrate 50 with respect to the nozzle unit 23 based on the image data of the thin film pattern. The control device 40 controls the rotation mechanism 27 based on the partition information of the fine area 50a and the solid area 50b. The solder resist landed on the fine region 50a is cured at a position relatively close to the nozzle hole 24a (FIG. 18A). The solder resist landed on the solid region 50b is cured at a position relatively far from the nozzle hole 24a (FIG. 18B).

  By performing such a thin film forming operation, as shown in FIG. 19B, the positional accuracy of the edge of the thin film pattern is improved in the fine region 50a of the substrate 50, and the thickness of the thin film pattern of the solder resist to be formed is uniform in the solid region 50b. It becomes possible to.

  FIG. 20 shows a nozzle unit according to a modification of the sixth embodiment. As shown in FIG. 20, the light source 25 a to 25 c provided in the nozzle unit and the irradiation position moving mechanism that can move the irradiation position of the light emitted from the light sources 25 a to 25 c to the substrate are not limited to one. You may provide the mechanism which can change the position arrange | positioned which may be two or more. For example, the light sources 25a to 25c are configured by a plurality of light emitting diodes (LEDs) arranged along the arrangement of the nozzle holes 24a. A plurality of irradiation position moving mechanisms that can move the irradiation position of the light beam emitted from each of the LEDs to the substrate may be included. The plurality of irradiation position moving mechanisms can be controlled independently by the control device 40 (FIGS. 18A to 18C). With such a configuration, the fine region 50a and the solid region 50b can be arranged more finely in the X-axis direction with the region irradiated with one LED as a unit region. The light sources 25a to 25c and the irradiation position moving mechanism may be separated from the nozzle unit 23 and attached to the frame of the thin film forming apparatus, for example. Moreover, these light sources 25a-25c and irradiation position moving mechanism may be provided with the mechanism which can change the position where they are arrange | positioned.

[Example 7]
Next, a thin film forming method according to Example 7 will be described with reference to FIGS. Hereinafter, differences from the first embodiment will be described, and description of the same configuration will be omitted.

  In Examples 1 to 6, a thin film pattern of solder resist was formed on the surface of the printed wiring board. In Example 7, an insulating film as an inner layer of the build-up substrate is formed.

  As shown in FIG. 21A, a first wiring pattern 81 made of copper or the like is formed on the surface of the core substrate 80. For example, the first wiring pattern 81 is formed by patterning a conductive film formed by plating.

  As shown in FIG. 21B, an insulating film (thin film pattern) 82 is formed on the core substrate 80 and the first wiring pattern 81. For the formation of the insulating film 82, the thin film forming method according to the first to sixth embodiments can be applied. For the insulating film 82, for example, an epoxy resin is used. An insulating film 82 made of an epoxy resin can be formed by discharging a droplet of the epoxy resin from the nozzle unit 23 (FIG. 1 and the like). The insulating film 83 is provided with a plurality of via holes 83. A part of the first wiring pattern 81 is exposed in the via hole 83. By applying the thin film formation method according to the first to sixth embodiments, the via hole 83 can be formed in the insulating film 82 without performing a process such as lithography or etching.

  As shown in FIG. 21C, a second wiring pattern 84 made of copper or the like is formed on the insulating film 82. For example, a semi-additive method can be applied to form the second wiring pattern 84. The second wiring pattern 84 is connected to the first wiring pattern 81 via the via hole 83. Since the thin film formation method according to the first to sixth embodiments is applied to the formation of the insulating film 82, the surface of the insulating film 82 can be flattened. Since the base surface on which the second wiring pattern 84 is formed is flat, it is possible to apply a semi-additive method similar to the conventional one to the formation of the second wiring pattern 84.

  As shown in FIG. 21D, an insulating film 85 is formed on the insulating film 82 and the second wiring pattern 84. For the formation of the insulating film 85, the thin film forming method according to the first to sixth embodiments can be applied. When the second wiring pattern 84 is the uppermost wiring pattern, a solder resist is used for the insulating film 85. When a wiring pattern is further formed on the insulating film 85, an epoxy resin or the like is used for the insulating film 85.

[Example 8]
FIG. 22A is a bottom view of the nozzle unit 23 of the thin film forming apparatus according to the eighth embodiment. Hereinafter, differences from the first embodiment will be described, and description of the same configuration will be omitted.

  In the first embodiment, the plurality of nozzle heads 24 are arranged in the Y-axis direction, that is, in the scanning direction of the substrate 50 (FIG. 1). In the eighth embodiment, a plurality of (for example, three) nozzle heads 24 are arranged in the X-axis direction, that is, the direction orthogonal to the scanning direction. The arrangement direction of the nozzle holes 24a is parallel to the X axis as in the case of the first embodiment. Ultraviolet light sources 25 are arranged on both sides (positive side and negative side of the Y axis) of each nozzle head 24.

  The interval between the nozzle heads 24 is equal to the width W of the unit scanning region 56 (FIG. 3). By scanning the substrate 50 (FIG. 1) once in the Y-axis direction, droplets of the thin film material are landed in the three unit scanning regions 56 (FIG. 3) arranged at intervals W in the X direction. Can be made. By shifting the distance in the X-axis direction by a distance W and performing scanning in the Y-axis direction, a thin film material droplet can be landed in the six unit scanning regions 56 continuous in the X-axis direction. By increasing the number of scans in the Y-axis direction for one unit scan region 56, the resolution of the thin film pattern in the X-axis direction can be increased.

  As shown in FIG. 22B, the nozzle heads 24 may be arranged in a matrix in the X-axis direction and the Y-axis direction. A plurality (for example, four) of nozzle heads 24 arranged in the Y-axis direction is the same as the arrangement of the nozzle heads 24 according to the first embodiment shown in FIGS. 2A and 2B. By arranging the nozzle heads 24 in a matrix, the number of scans required to form a thin film pattern can be reduced.

[Example 9]
FIG. 23 is a bottom view of the nozzle unit 23 of the thin film forming apparatus according to the ninth embodiment. Hereinafter, differences from the first embodiment will be described, and description of the same configuration will be omitted.

  In the first embodiment, the plurality of nozzle heads 24 are arranged in the Y-axis direction, but in the ninth embodiment, a plurality of (for example, four) nozzle heads 24 are arranged in the X-axis direction. As a whole, the four nozzle heads 24 have nozzle holes 24a arranged at equal intervals in the X-axis direction (pitch 4P shown in FIG. 2B). Even between the nozzle heads 24 adjacent to each other in the X-axis direction, the relative position of the nozzle head 24 in the X direction is adjusted so that the pitch of the nozzle holes becomes equal to the pitch of the nozzle holes in the nozzle head 24. Yes. For this adjustment, the nozzle heads 24 adjacent in the X-axis direction are arranged so as to be shifted from each other in the Y-axis direction. With the four nozzle heads 24, a droplet of a thin film material can be landed on an area having a width of 4 W in one scan.

  A procedure for forming the edge pattern 60 will be described with reference to FIGS. 24A to 24D. The edge pattern 60 is composed of a plurality of pixels arranged at a pitch P, for example. 24A to 24D show edge patterns 60 after the completion of the first to fourth scans, respectively. In FIG. 24A to FIG. 24D, a pixel on which the thin film material has landed is indicated by a black circle symbol, and a pixel on which the thin film material has not landed is indicated by a hollow circle symbol.

  By the first scan, the thin film material lands on every third pixel in the X-axis direction. After completion of the first scan, the substrate 50 (FIG. 1) is shifted from the nozzle unit 23 by a distance equal to the pitch P in the X-axis direction, and the second scan is performed. Similarly, the thin film material can be landed on all the pixels constituting the edge pattern 60 by performing the third and fourth scans. After the edge pattern 60 is formed, planar patterns 62 and 64 (FIGS. 4G to 4L) are formed as in the first embodiment.

  As shown in the ninth embodiment, when a plurality of nozzle heads 24 are arranged in the X-axis direction (direction orthogonal to the scanning direction), the range in the X-axis direction in which the thin film material can be landed by one scan is wide. Become.

  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 Stage 23, 23R Nozzle unit 24 Nozzle head 24a Nozzle holes 24I, 24J Nozzle rows 25, 25a, 25b Ultraviolet light source 26 Nozzle holder 27 Rotating mechanism 28 Optical system 29 Nozzle unit support mechanism 30 Imaging device 31 Post 32 Beam 40 Control device 41 Input device 42 Output device 50 Substrate 50a Fine region 50b Solid region 51 Insulating region 52 Land region 55 Thin film pattern 55a Droplet 56 Unit scanning region 60, 61 Edge pattern 62 Planar pattern 63 Unit scanning region boundary Line 64 Planar pattern 65 Edge pattern 66 Planar pattern 70 Solid region ultraviolet light source 80 Core substrate 81 First wiring pattern 82 Insulating film 83 Via hole 84 Second wiring pattern 85 Insulating film

According to another aspect of the invention,
(A) A thin film in the first region of the substrate whose surface is divided into a first region including an edge of a thin film pattern to be formed and a second region where a solid thin film is formed. Attaching a photocurable thin film material to the region to be formed;
(B) after the step a, irradiating the thin film material attached to the first region of the substrate with light to cure the thin film material;
(C) depositing the thin film material in the second region;
(D) after the step c, irradiating the thin film material adhering to the second region with light to cure the thin film material, and after adhering to the second region, the step There is provided a thin film forming method in which the time until the thin film material is irradiated with light in d is longer than the time until the thin film material is irradiated with light in the step b after being attached to the first region.

A thin film pattern can be formed with a resolution of 1200 dpi in the X direction by discharging droplets of a thin film material from each nozzle hole 24a of the nozzle unit 23 while moving the substrate 50 (FIG. 1) in the Y direction. By performing the scanning twice while shifting by P / 2 in the X direction, the resolution in the X direction can be doubled to 2400 dpi. The two scans can be realized by a reciprocating scan in which the directions of the first scan and the second scan are reversed. The resolution in the Y direction is determined by the moving speed of the substrate 50 and the discharge period of droplets from the nozzle holes 24a.

FIG. 8A shows a plan view of the substrate 50 before and after the first scan, and the nozzle unit 23. The nozzle unit 23 includes two subunits 23A and 23B. The configuration of each of the subunits 23A and 23B is the same as that of the nozzle unit 23 (FIG. 2A) of the first embodiment. The subunits 23A and 23B are arranged at a certain interval in the Y direction. The subunit 23A is arranged on the positive side of the Y axis with respect to the subunit 23B.

In FIG. 9, the top view of the nozzle unit 23 of the thin film forming apparatus by Example 4 is shown. The nozzle unit 23 includes two subunits 23A and 23B. Sub unit 23A, 23B
Are attached to the same nozzle holder 26 and have the same configuration as the nozzle unit 23 (FIGS. 2A and 2B) of the first embodiment. That is, each of the subunits 23 </ b> A and 23 </ b> B includes four nozzle heads 24 and five ultraviolet light sources 25. The two subunits 23A and 23B are arranged at the same position in the X direction. The subunit 23A is disposed closer to the positive side of the Y axis than the subunit 23B.

15A and 15B are side views of the nozzle unit 23 and the substrate 50 when the thin film pattern is formed by the method according to the fifth embodiment. The control device 40 (FIG. 1) moves the substrate 50 with respect to the nozzle unit 23 at a constant feed speed, for example, in the negative direction of the Y axis. Based on the image data of the thin film pattern, the control device 40 applies a voltage pulse to the nozzle holes 24a at a predetermined cycle, and discharges the solder resist from the nozzle holes 24a. For example, the feeding speed of the substrate 50 is about 300 mm / s, and the frequency at which the nozzle head 24 ejects the solder resist is about 30 kHz. The height from the substrate 50 to the nozzle head 24 is about 0.5 mm to 1 mm, and the height to the light sources 25a and 25b is about 20 mm to 30 mm. When the area where the solder resist has landed is the fine area 50a (FIG. 13A), the control device 40, as shown in FIG. 15A, emits the light from the light source 25a disposed at a position relatively close to the nozzle hole 24a. The solder resist is cured by irradiation. For example, the solder resist that has landed on the fine region 50 a is cured about 0.1 s after landing on the substrate 50. When the area where the solder resist has landed is a solid area 50b (FIG. 13A), as shown in FIG. 15B, the solder resist is irradiated by light irradiation from a light source 25b disposed at a position relatively far from the nozzle hole 24a. Is cured. For example, the solder resist that has landed on the solid region 50 b is cured about 0.3 s after landing on the substrate 50.

The control device 40 moves the substrate 50 with respect to the nozzle unit 23 at a constant feed speed, for example, in the negative direction of the Y axis. Based on the stored image data, the control device 40 applies a voltage pulse to the nozzle holes 24a at a predetermined cycle, and discharges the solder resist from the nozzle holes 24a. For example, the feeding speed of the substrate 50 is about 300 mm / s, and the frequency at which the nozzle head 24 ejects the solder resist is about 30 kHz. The height from the substrate 50 to the nozzle head 24 is about 0.5 mm to 1 mm, and the height to the light source 25 is about 20 mm to 30 mm.

As shown in FIG. 21B, an insulating film (thin film pattern) 82 is formed on the core substrate 80 and the first wiring pattern 81. For the formation of the insulating film 82, the thin film forming method according to the first to sixth embodiments can be applied. For the insulating film 82, for example, an epoxy resin is used. An insulating film 82 made of an epoxy resin can be formed by discharging a droplet of the epoxy resin from the nozzle unit 23 (FIG. 1 and the like). A plurality of via holes 83 are provided in the insulating film 82 . A part of the first wiring pattern 81 is exposed in the via hole 83. By applying the thin film formation method according to the first to sixth embodiments, the via hole 83 can be formed in the insulating film 82 without performing a process such as lithography or etching.

Claims (28)

The thin film material is formed at the edge of the region where the thin film pattern is formed by repeating the landing of the droplet of the thin film material on the edge of the region where the thin film pattern is formed on the surface of the substrate and the curing of the landed thin film material. Forming an edge pattern comprising:
Landing a droplet of thin film material on an internal region defined by an edge pattern;
And a step of curing the thin film material landed on the internal region.   In the step of forming the edge pattern, the thin film material is discharged from the nozzle hole while moving one of the nozzle unit having a plurality of nozzle holes for discharging the thin film material and the substrate with respect to the other. The thin film forming method according to claim 1, wherein droplets of a thin film material are landed on an edge of a region where the thin film pattern is formed.   The thin film material is a photo-curing material that is cured by light irradiation, and in the step of forming the edge pattern, one of the light source that emits light for curing the thin film material and the substrate is set against the other. The thin film forming method according to claim 2, wherein the thin film material landed on the substrate is cured by moving the substrate.   In the step of forming the edge pattern in the process of discharging the thin film material from the nozzle hole as one scan while moving one of the nozzle unit and the substrate in one direction with respect to the other, The thin film forming method according to claim 3, wherein one region is scanned a plurality of times.   The thin film forming method according to claim 4, wherein the plurality of scans are realized by reciprocal scanning. In the step of forming the edge pattern, during the scanning, the thin film material landed on the substrate is irradiated with light from the light source,
In the step of landing the thin film material on the internal region, light is not irradiated during scanning,
4. After the scanning of the step of landing the thin film material on the internal region is completed, the thin film material landed on the internal region is irradiated with light while moving one of the light source and the substrate relative to the other. 6. The thin film forming method according to any one of items 1 to 5.   In the step of forming the edge pattern, it is landed on the edge of the region where the thin film pattern is to be formed, and other droplets of the thin film material are landed and cured so as to partially overlap the cured thin film material. The thin film formation method according to any one of claims 1 to 6, wherein the edge pattern is made higher than a height of the thin film material formed by curing one droplet of the thin film material.   8. The edge pattern is formed by curing the surface layer portion of the thin film material that has landed on the substrate and leaving the inside uncured in the step of forming the edge pattern. 9. A method for forming a thin film according to 1.   9. The landing point distribution density when the thin film material is landed on the inner region is set lower than the landing point distribution density when the thin film material is landed when the edge pattern is formed. The thin film forming method according to item.   The thin film formation method according to claim 9, wherein a volume of a droplet when the thin film material is landed on the inner region is larger than a volume of the droplet when the edge pattern is formed. The time until the thin film material is cured after landing the thin film material on the internal region is the time until the thin film material is cured after landing the thin film material on the edge of the region where the thin film pattern is formed. The thin film forming method according to claim 1, which is longer. When the surface of the substrate is divided into at least two regions by a virtual boundary line intersecting an edge of the region forming the thin film pattern,
The step of forming the edge pattern, the step of landing a droplet of a thin film material on the inner region, and the step of curing the thin film material landed on the inner region are performed on a region on one side of the virtual boundary line. The thin film forming method according to claim 1, wherein the thin film forming method is executed for the region on the other side of the virtual boundary line.   The thin film material that has landed on the internal region spreads in the in-plane direction of the substrate, the thin film material that has landed on a plurality of landing points continues, and the landing points adjacent to each other cannot be distinguished from each other. The thin film forming method according to claim 1, wherein the material is cured. The thin film material is a photocurable material,
The step of landing the thin film material droplet on the inner region causes the thin film material droplet to land on one side of the virtual boundary line in the inner region, and then the thin film material liquid on the other side. Land a drop,
The step of curing the thin film material that has landed on the inner region cures the thin film material on both sides of the virtual boundary while moving the region irradiated with light along the virtual boundary line. 14. The thin film forming method according to any one of 1 to 13. A first wiring pattern is formed on the surface of the substrate;
The thin film pattern formed in the step of forming the edge pattern, the step of landing a droplet of a thin film material on the internal region, and the step of curing the thin film material landed on the internal region includes the substrate and the first pattern. A plurality of via holes covering one wiring pattern and exposing a part of the first wiring pattern;
After the step of curing the thin film material that has landed on the internal region,
The thin film formation method according to claim 1, further comprising: forming a second wiring pattern connected to the first wiring pattern through the via hole on the thin film pattern. (A) A thin film in the first region of the substrate whose surface is divided into a first region including an edge of a thin film pattern to be formed and a second region where a solid thin film is formed. Attaching a photocurable thin film material to the region to be formed;
(B) after the step a, irradiating the thin film material attached to the first region of the substrate with light to cure the thin film material;
(C) depositing the thin film material in the second region;
(D) after the step c, irradiating the thin film material adhering to the second region substrate with light to cure the thin film material, and after adhering to the second region, A method for forming a thin film, wherein the time until the thin film material is irradiated with light in the step d is longer than the time until the thin film material is irradiated with light in the step b after adhering to the first region. A stage for holding a substrate;
Opposite the substrate held on the stage, the surface of the substrate is irradiated with a plurality of nozzle holes for discharging droplets of a photocurable thin film material, and the thin film material attached to the substrate is irradiated with curing light. A nozzle unit provided with a light source;
A moving mechanism for moving one of the nozzle unit and the stage relative to the other in a direction parallel to the surface of the substrate;
A control device storing image data of a thin film pattern to be formed on the substrate,
The controller is
Based on the image data, after the droplet of the thin film material has landed on the edge of the thin film pattern, the thin film material landed on the edge is irradiated with light from the light source to form an edge pattern, and then the thin film The moving mechanism, so that a droplet of the thin film material has landed inside a region for forming a pattern, and the thin film material landed inside the region for forming the thin film is irradiated with light from the light source, A thin film forming apparatus for controlling the nozzle unit and the light source. The control device causes one of the nozzle unit and the stage to move in the first direction with respect to the other while discharging a droplet of a thin film material from the nozzle hole,
The thin film forming apparatus according to claim 17, wherein the light source irradiates light at a position shifted in the first direction from a landing point of the thin film material discharged from the nozzle hole.   19. The thin film forming apparatus according to claim 17, wherein the intensity of light applied to the thin film material by the light source is such that at least a surface layer portion of the thin film material landed on the substrate is cured.   The control device performs a process of discharging a thin film material from the nozzle hole as one scan while moving one of the nozzle unit and the substrate in one direction with respect to the other, to one region of the substrate. The thin film forming apparatus according to claim 17, wherein the edge pattern is formed by performing scanning a plurality of times.   21. The thin film forming method according to claim 20, wherein the control device realizes a plurality of scans by reciprocating scans.   The control device is configured so that a distribution density of landing points when the thin film material is landed on the internal region is lower than a distribution density of landing points when the thin film material is landed when forming the edge pattern. The thin film formation apparatus of any one of Claims 17 thru | or 21 which controls a nozzle unit.   23. The control device according to claim 22, wherein the control device controls the nozzle unit so that a volume of a droplet when a thin film material is landed on the internal region is larger than a volume of the droplet when the edge pattern is formed. Thin film forming equipment. The nozzle unit includes a plurality of nozzle heads arranged in the first direction, each nozzle head having a plurality of nozzle holes, and the plurality of nozzle heads as a whole, The nozzle holes are arranged at equal intervals in the orthogonal direction,
The thin film forming apparatus according to claim 18, wherein the light sources are arranged between the nozzle heads and outside the nozzle heads arranged on the outermost side. When an XY orthogonal coordinate system is defined on the surface of the substrate held by the stage,
The nozzle unit includes a nozzle row including a plurality of nozzle holes arranged in the X direction,
The light source includes an edge curing light source and a solid region curing light source,
The edge curing light source is disposed beside the nozzle row, and irradiates light to a region to which droplets discharged from the nozzle row adhere in the X direction,
The thin film forming apparatus according to claim 17, wherein the solid region curing light source irradiates light in a region shifted to the X direction negative side with respect to the X direction with respect to the region irradiated by the edge curing light source. A stage for holding a substrate;
A nozzle unit provided with a plurality of nozzle holes for discharging a liquid material having photocurability and insulation toward the substrate held on the stage and attaching the liquid material to the substrate;
A moving mechanism for moving one of the stage and the nozzle unit in the Y direction parallel to the surface of the substrate with respect to the other;
A first light source that is disposed away from the plurality of nozzle holes in the Y direction and cures the liquid material by irradiating the liquid material attached to the substrate with light;
A second light source that is disposed further away from the first light source in the Y direction from the plurality of nozzle holes and that cures the liquid material by irradiating the liquid material attached to the substrate with light;
A controller that stores image data defining a thin film pattern to be formed on the surface of the substrate, and controls the moving mechanism, the nozzle unit, and the first and second light sources based on the image data;
With
In the control device, the first light source cures the liquid material adhering to the first region including the edge of the thin film pattern, and the second light source forms the second region where the thin film pattern is solid. A thin film forming apparatus for controlling the first and second light sources so as to cure the liquid material adhered to the substrate.   27. The thin film forming apparatus according to claim 26, wherein the control device stores information for partitioning the thin film pattern into the first region and the second region.   27. The first and second light sources are constituted by a plurality of light emitting diodes arranged along an array of the plurality of nozzles, and each of the plurality of light emitting diodes can be independently controlled to be turned on and off. Or the thin film forming apparatus according to 27.

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