JP7054021B2 - Printed circuit boards and light emitting devices and their manufacturing methods - Google Patents

Description

The present invention relates to a printed circuit board, a light emitting device, and a method for manufacturing the same.

In printed circuit boards, resins such as epoxy resins and polyimide resins are often used as insulating base materials, and some printed circuit boards also use reinforcing materials such as glass cloth, such as glass epoxy boards. The printed circuit board including such a resin layer is provided with a plurality of through holes for various purposes. Conventionally, the through hole is formed by machining such as a drill or a router, but as disclosed in Patent Document 1, for example, it may be formed by laser machining in recent years.

Japanese Unexamined Patent Publication No. 2012-61480

Laser machining has the advantage of being able to form through holes with high accuracy, but as disclosed in Patent Document 1, it is necessary to scan the laser beam multiple times so as to orbit along the outer edge of the through holes to be formed. be. Therefore, it has been desired to reduce the number of scans in order to shorten the time required for laser processing.
It is an object of the present embodiment to provide a printed circuit board capable of shortening the time required for laser processing and a method for manufacturing the printed circuit board.

The method for manufacturing a printed substrate according to the embodiment of the present disclosure includes a plate-shaped base material having an insulating property, a first metal layer provided on one surface of the base material, and a first metal layer provided on the other side of the base material. A laser processing step of forming a through hole penetrating in the thickness direction of the original substrate by irradiating the original substrate including the second metal layer with a laser beam from the first metal layer side is included. Prior to the processing step, there is an etching step of removing the second metal layer arranged in the area to be irradiated with the laser beam by etching.

The printed circuit board according to the embodiment of the present disclosure is provided on a plate-shaped base material having an insulating property, a first metal layer provided on one surface of the base material, and the other surface of the base material. The base material has a through hole that penetrates in the thickness direction, and the second metal layer is separated from the through hole by a predetermined distance or more in a bottom view. It is provided.

According to the printed circuit board and the manufacturing method thereof according to the embodiment of the present disclosure, the time required for laser processing can be shortened.

It is a flowchart which shows the procedure of the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is sectional drawing which shows the structure of the original board used in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is a top view which shows the etching process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is sectional drawing which shows the etching process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment, and shows the sectional drawing in line IIIB-IIIB of FIG. 3A. It is sectional drawing which shows the laser processing process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is a block diagram which shows the structure of the laser processing apparatus used in the laser processing process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is sectional drawing which shows the plating process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is a top view which shows the wiring pattern forming process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is a bottom view which shows the wiring pattern formation process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is sectional drawing which shows the wiring pattern formation process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment, and shows the sectional drawing in the VIC-VIC line of FIG. It is sectional drawing which shows the 1st modification of the etching process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is sectional drawing which shows the 2nd modification of the etching process in the manufacturing method of the printed circuit board which concerns on 1st Embodiment. It is a flowchart which shows the procedure of the manufacturing method of the light emitting device which concerns on 2nd Embodiment. It is a top view which shows the light emitting element mounting process in the manufacturing method of the light emitting device which concerns on 2nd Embodiment. It is sectional drawing which shows the light emitting element mounting process in the manufacturing method of the light emitting device which concerns on 2nd Embodiment, and shows the sectional view in the IXB-IXB line of FIG. It is a top view which shows the light-shielding member forming process in the manufacturing method of the light emitting device which concerns on 2nd Embodiment. It is sectional drawing which shows the light-shielding member forming process in the manufacturing method of the light emitting device which concerns on 2nd Embodiment, and shows the sectional drawing in line XB-XB of FIG. It is a top view which shows the translucent member forming process in the manufacturing method of the light emitting device which concerns on 2nd Embodiment. It is sectional drawing which shows the translucent member forming process in the manufacturing method of the light emitting apparatus which concerns on 2nd Embodiment, and shows the sectional view in the XIB-XIB line of FIG. 11A.

Hereinafter, the printed circuit board, the light emitting device, and the manufacturing method thereof according to the embodiment of the present invention will be described.
Since the drawings referred to in the following description schematically show the embodiment of the present invention, the scale, spacing, positional relationship, etc. of each member are exaggerated, or some of the members are not shown. May have been. In addition, the scales and spacing of the members may not match in the plan view, bottom view, and cross-sectional view thereof. Further, in the following description, the same or the same quality members are shown in principle for the same name and reference numeral, and detailed description thereof will be omitted as appropriate.

In the present specification, a substrate at a stage prior to the laser processing step is referred to as a "original substrate", and a substrate on which a through hole is formed by performing the laser processing step is referred to as a "printed circuit board".

As used herein, the broad "through hole" includes a point-like narrow "through hole" that can be formed without scanning the laser beam and an "opening" that can be formed by scanning the laser beam. Further, the "opening" is formed by scanning the laser beam linearly and / or curvedly into a "hole having substantially the same shape as the scanning line", and the pulsed laser beam is scanned so as to surround a predetermined region. It includes a "hole having substantially the same shape as the predetermined region" to be formed.

<First Embodiment>
[Printed circuit board and its manufacturing method]
The printed circuit board and the manufacturing method thereof according to the first embodiment will be described with reference to FIGS. 1 to 6C.
FIG. 1 is a flowchart showing a procedure of a method for manufacturing a printed circuit board according to the first embodiment. FIG. 2 is a cross-sectional view showing the configuration of the original substrate used in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 3A is a plan view showing an etching process in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 3B is a cross-sectional view showing an etching process in the method for manufacturing a printed circuit board according to the first embodiment, and shows a cross-sectional view taken along the line IIIB-IIIB of FIG. 3A. FIG. 4A is a cross-sectional view showing a laser processing step in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 4B is a block diagram showing a configuration of a laser processing apparatus used in a laser processing step in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 5 is a cross-sectional view showing a plating process in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 6A is a plan view showing a wiring pattern forming step in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 6B is a bottom view showing a wiring pattern forming step in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 6C is a cross-sectional view showing a wiring pattern forming step in the method for manufacturing a printed circuit board according to the first embodiment, and shows a cross section in the VIC-VIC line of FIG. 6A.

Although FIG. 3A is a bottom view, it is shown by hatching the area to be irradiated with the laser beam for convenience. Further, in each cross-sectional view shown in FIGS. 3B and after, the description of the detailed configuration of the base material is omitted. Further, in the plan view shown in FIG. 6A and the bottom view shown in FIG. 6B, the region where the first metal layer, the second metal layer, and the third metal layer are left as the wiring pattern is hatched for convenience. ..

[Printed circuit board configuration]
The printed circuit board 1 manufactured by the manufacturing method according to the first embodiment is formed on the upper surface of a plate-shaped base material 11 having an insulating property, as shown in FIGS. 6A to 6C showing the wiring pattern forming step which is the final step. A first metal layer 12 is provided on the lower surface thereof, and a second metal layer 13 is provided on the lower surface thereof, and an opening 15 penetrating the printed circuit board 1 in the thickness direction is provided at a predetermined position. The printed circuit board 1 is further provided with a third metal layer 14 that continuously covers the inner side surfaces of the first metal layer 12, the second metal layer 13, and the opening 15, and the first metal layer 12 and the second metal layer. It is electrically connected to 13. Further, the first metal layer 12, the second metal layer 13, and the third metal layer 14 constitute a wiring pattern of the printed circuit board 1. Further, the corner portion of the printed circuit board 1 of the present embodiment is provided with a hole portion 18 for positioning and handling of the printed circuit board 1.
The detailed configuration of the printed circuit board 1 will be described together with the manufacturing method thereof.

[Manufacturing method of printed circuit board]
The method for manufacturing a printed circuit board according to the first embodiment includes a raw circuit board preparation step S11, an etching step S12, a laser processing step S13, a plating step S14, and a wiring pattern forming step S15.

The original substrate preparation step S11 is a step of preparing the original substrate 10 which is the raw material of the printed circuit board 1. The original substrate 10 of the printed circuit board 1 is provided with an insulating plate-shaped base material 11 and a first metal layer 12 on the upper surface side, which is one surface of the base material 11, and on the lower surface side, which is the other surface. A second metal layer 13 is provided.

The original substrate 10 can be manufactured by attaching metal foils to both sides of the base material 11 or forming a metal film on both sides of the base material 11 by plating, sputtering, vapor deposition, or the like. The original substrate 10 may be manufactured by itself or may be purchased on the market. The original substrate 10 is, for example, a rigid substrate, but may be a flexible substrate.
Further, the original substrate 10 may be provided with a hole portion 18 for positioning and handling of the original substrate 10 to the printed circuit board 1 in addition to the opening portion 15 formed by laser processing. Such a hole 18 can be formed by, for example, a drill or a router.

The base material 11 is configured by alternately laminating a plurality of layers of a resin layer 111 and a glass cloth 112 woven by warp threads 112a and weft threads 112b. As the glass cloth 112, for example, E glass made of SiO ₂ -Al ₂ O ₃ -CaO-B ₂ O ₃ or the like, S glass made of SiO ₂ -Al ₂ O ₃ -MgO or the like, or the like is used. The glass cloth 112 is impregnated with the resin constituting the resin layer 111, and the resin layer 111 and the glass cloth 112 integrally form a strong base material 11. The base material 11 preferably has at least three or more layers of glass cloth 112. By laminating a plurality of glass cloths, the uneven distribution of the glass cloths of the warp threads 112a and the weft threads 112b is improved and the uniformity is increased, so that the processed surface can be uniformly finished when processed by a laser.

The type of resin constituting the resin layer 111 is not particularly limited. Examples of the resin constituting the resin layer 111 include epoxy resin, polyimide resin, polyethylene terephthalate resin, polyethylene naphthalate resin, bismaleimide triazine resin, phenol resin, silicone resin, modified silicone resin, epoxy-modified silicone resin, polyphenylene ether resin, and liquid crystal. Examples include polymer resins and combinations thereof.

Further, the base material 11 may or may not contain a reinforcing material for improving the strength, as in the glass cloth 112 of the present embodiment. Examples of the material of the reinforcing material include glass fiber, ceramic fiber, carbon fiber, aramid fiber, and a combination thereof. Examples of the shape of the reinforcing material include woven cloth, non-woven fabric, paper, and felt. Further, the reinforcing material may be dispersed in the resin layer 111 as a filler.

Specific examples of the base material 11 include a glass epoxy substrate and a polycarbonate substrate. The thickness of the base material 11 is not particularly limited, but can be, for example, about 200 to 500 μm.

In the original substrate 10, the first metal layer 12 is provided so as to cover the upper surface which is one surface of the plate-shaped base material 11, and the second metal layer 13 is the lower surface which is the other surface of the base material 11. It is provided to cover the. The first metal layer 12 and the second metal layer 13 are metal layers for forming the wiring pattern of the printed circuit board 1, respectively.
Further, since the first metal layer 12 and the second metal layer 13 have higher thermal conductivity than the base material 11, the excess heat energy accumulated in the vicinity of the surface of the original substrate 10 during laser processing is effectively used. It has the function of dissipating. Further, the first metal layer 12 and the second metal layer 13 also have a function of blocking the permeation of oxygen from the outside to the base material 11, particularly the resin layer 111. Due to the synergistic effect of these functions, the first metal layer 12 and the second metal layer 13 suppress the occurrence of undesired thermal damage such as charring and scooping during laser processing. From such a viewpoint, it is preferable that the first metal layer 12 and the second metal layer 13 cover substantially the entire surface of the base material 11 on which the first metal layer 12 and the second metal layer 13 are provided.

The type of metal constituting the first metal layer 12 and the second metal layer 13 is not particularly limited, but it is preferable that the electric resistance is low from the viewpoint of being used as a wiring pattern of an electric circuit. Further, the type of metal constituting the first metal layer 12 and the second metal layer 13 is preferably one having a high thermal conductivity from the viewpoint of suppressing the occurrence of undesired thermal damage in the laser processing step S13. Examples of the metals constituting the first metal layer 12 and the second metal layer 13 are one or more metals selected from the group consisting of Cu, Ag, Au, Ni and Al, or these metals as main components. Can be mentioned as an alloy contained as.
The thicknesses of the first metal layer 12 and the second metal layer 13 are not particularly limited, but may be as long as they have a thickness that functions as wiring, and are preferably 1 μm or more, and are accompanied by the time required for laser processing and laser processing. It is preferably 18 μm or less so that the amount of debris generated does not become too large. Further, when the first metal layer 12 and / and the second metal layer 13 are removed by etching before laser processing, the upper limit of the thickness of the first metal layer 12 and the second metal layer 13 is not particularly limited. It is preferable that the thickness is 105 μm or less so as not to use an excessive amount of material.

Further, depending on the metal material used for the first metal layer 12 and the second metal layer 13, the adhesive strength is improved and the metal material is migrated between the first metal layer 12 and the second metal layer 13 and the base material 11. Other metal layers for the purpose of prevention and the like may be arranged. Examples of such a metal layer include a Ni layer, a Cr layer, and a NiCr alloy layer having a thickness of about several hundred nm.

In the etching step S12, before performing the laser processing step S13, the second metal layer 13 arranged in the laser light irradiation scheduled region 21 and its vicinity, which is the region to be irradiated with the laser light 20, is etched. It is a process of removing with. This eliminates the need to remove the second metal layer 13 by laser processing, so that the number of times the laser beam 20 is scanned can be reduced accordingly.

In order to reduce the number of scans of the laser beam 20, in addition to removing the second metal layer 13, the first metal layer 12 in the laser beam irradiation planned region 21 and its vicinity may be removed, but at least. , It is preferable to remove the second metal layer 13. Compared with the first metal layer 12 provided on the upper surface side which is the incident surface of the laser beam 20, the second metal layer 13 provided on the lower surface side requires more scanning times of the laser beam 20 for laser processing. In many cases, processing abnormalities are likely to occur on the cut surface due to the influence of heat. Therefore, it is preferable to remove the second metal layer 13 in order to reduce the processing time and improve the processing quality. Further, by removing the first metal layer 12 provided on the upper surface side, it is possible to reduce the number of scans during laser processing and also reduce the occurrence of debris.

The etching of the second metal layer 13 can be performed by the same method as the etching for forming a wiring pattern in the conventional method for manufacturing a printed circuit board.
First, the first metal layer 12 and the second metal layer 13 in other regions are masked so that the second metal layer removal region 23, which is a region to be removed by etching, is exposed. Next, the second metal layer 13 exposed from the mask is removed by using an appropriate etching solution according to the type of metal used in the second metal layer 13.

In the present embodiment, in the bottom view, the second metal layer removing region 23 from which the second metal layer 13 is removed by etching is long according to the shape of the opening formation planned region 24 which is a region forming the opening 15. It is defined to include the laser beam irradiation scheduled area 21 set in a ring shape such as a circle, a circle, an ellipse, and a polygon. When forming a through hole in a narrow sense, the second metal layer removing region 23 is defined as a region including the through hole. That is, the second metal layer removing region 23 is formed wider than the region 24 where the opening is planned to be formed. More specifically, the outer edge of the second metal layer removing region 23 is removed so as to be separated from the laser light irradiation scheduled region 21 which is the outer edge of the opening planned opening region 24 by a predetermined distance or more.

Here, the predetermined separation distance d that is separated from the laser light irradiation scheduled region 21 forms the second metal layer removal region 23 by the positional accuracy in which the laser light 20 which is the laser light irradiation scheduled region 21 is irradiated and by etching. It is determined to be larger than the relative positional accuracy determined from the positional accuracy of the case. Specifically, the separation distance d is preferably 10 μm or more, and more preferably 20 μm or more. Thereby, even if the region irradiated with the laser beam 20 is displaced within the positional accuracy, the laser beam 20 can be prevented from being irradiated to the second metal layer 13. Therefore, even if the number of scans of the laser beam 20 is reduced by the amount of removing the second metal layer 13, the annular through groove 25 can be surely formed on the outer edge of the region 24 where the opening is planned to be formed. Further, as a result, the opening 15 can be formed with high reliability.
In order to efficiently dissipate the heat accumulated in the base material 11 during laser processing, and in the plating step S14, sufficient film strength is obtained for the third metal layer 14 formed on the inner side surface of the opening 13. Therefore, the shorter the separation distance d is, the more preferable it is, and for example, it is preferably 500 μm or less.

The laser processing step S13 is a step of forming a through hole in a broad sense by irradiating the original substrate 10 on which the second metal layer removing region 23 is formed with a laser beam 20. When the opening 15 is formed as a through hole in a broad sense, the first metal layer 12 side is formed on the original substrate 10 on which the second metal layer removing region 23 is formed, along the laser light irradiation scheduled region 21 set in an annular shape. Is irradiated with laser light 20. By the irradiation of the laser beam 20, an annular through groove 25 penetrating the original substrate 10 in the thickness direction is formed, and the portion 19 separated by the through groove 25 is naturally dropped or air blown from the upper surface side or the lower surface side. By being extruded and removed, an opening 15 is formed in the original substrate 10. Thereby, the printed circuit board 1 can be manufactured.
When the through hole in a broad sense formed by laser processing is not accompanied by scanning of the laser beam 20, a point-shaped through hole is formed instead of the annular through groove 25 in a plan view.

More specifically, the irradiation of the laser beam 20 is performed by scanning a plurality of times so as to orbit along the laser beam scheduled irradiation region 21 defined in a ring shape on the outer edge of the opening planned opening region 24. The number of scans of the laser beam 20 depends on various conditions such as the type, power, and fluence of the laser beam 20, the material and thickness of the first metal layer 12 used for the original substrate 10, and the material and thickness of the base material 11. Is determined. In the present embodiment, since the second metal layer 13 in the laser light irradiation scheduled region 21 and its vicinity is removed in advance in the etching step S12, the second metal layer 13 is not the target of the laser processing in this step. That is, the number of scans of the laser beam 20 can be reduced by the amount that the second metal layer 13 is not laser-processed.

For example, the original substrate 10 is a glass epoxy substrate in which the first metal layer 12 and the second metal layer 13 each have a copper foil having a thickness of about several μm, and the base material 11 has a thickness of about several hundred μm. The case will be described. In this case, in order to form the through groove 25 by laser processing without removing the second metal layer 13, the second metal layer 13 is removed in advance when laser light scanning is required about 60 times. The number of scans can be reduced to about 40 to 45. By reducing the number of scans, the laser processing time, which requires about 90 minutes, for example, can be reduced to about 60 to 70 minutes. On the other hand, the time required for etching the first metal layer and the second metal layer 13 can be finished at a time interval of, for example, about 1 minute per sheet by continuous processing. Therefore, the total productivity can be increased by performing the laser processing step S13 after performing the etching step S12.

When scanning the laser beam 20 in an annular shape, the scanning direction may be either clockwise or counterclockwise. Further, the depth of the condensing point of the laser beam 20 in the thickness direction of the original substrate 10 may be constant regardless of the progress of the laser processing, or may be constant depending on the progress of the laser processing. It may be changed. For example, when the thickness of the original substrate 10 is non-uniform, the depth of the condensing point of the laser beam 20 may be changed according to the thickness at the processing position of the original substrate 10.

Further, when scanning the laser beam 20 a plurality of times, it is preferable to scan the laser beam 20 so that the irradiation interval between the laps at each point where the laser beam 20 is irradiated is 5 milliseconds or more. By doing so, it becomes possible to effectively dissipate the excess heat energy accumulated in the base material 11 during the circuit time to the first metal layer 12 and the second metal layer 13, and the base material 11 can be dissipated. It is possible to suppress the occurrence of thermal damage in the laser-processed portion of the above.

The type of the laser beam 20 is not particularly limited as long as it can appropriately form the through groove 25 in the original substrate 10, but the laser light 20 shown below is preferable.
The laser light 20 is preferably a pulse laser that can instantaneously obtain high power in order to suppress the influence of heat on the original substrate 10. This makes it easier to handle raw substrates 10 of various materials and thicknesses.

When a pulse laser is used as the laser beam 20, the following conditions are preferable.
The emission wavelength of the laser beam 20 is preferably in the range of 250 to 2000 nm, preferably in the range of 250 to 1500 nm, from the viewpoint of suppressing the occurrence of undesired thermal damage in the laser-processed portion of the base material 11. Is more preferable. For example, the wavelength of the laser beam 20 is 355 nm.

The power of the laser beam 20 is preferably 10 W or more from the viewpoint of increasing the laser processing speed. Further, the upper limit of the power of the laser beam 20 is not particularly limited as long as the total irradiation energy determined when combined with the pulse frequency and the scanning speed is suitable for the original substrate 10 to be processed. not. Therefore, as the laser beam 20, for example, a laser beam having a power of about 60 W can be used.
The pulse width of the laser beam 20 is preferably in the range of 10 picoseconds to 100 nanoseconds from the viewpoint of improving the laser processing quality.
The pulse frequency of the laser beam 20 is preferably 100 kHz to 3 MHz, more preferably 1 MHz to 3 MHz, from the viewpoint of improving the laser processing quality.

For example, when the wavelength of the laser light 20 is 355 nm, the pulse energy of the laser light 20 is preferably 3 μJ or more from the viewpoint of increasing the laser processing speed. Further, when the wavelength of the laser light 20 is 355 nm, the fluence of the laser light 20 on the upper surface of the original substrate 10 of the laser light 20 is 3 J / cm ² or more from the viewpoint of increasing the laser processing speed. The fluence of the laser beam 20 at the light spot is preferably 10 J / cm ² or more.
The beam diameter, which is the width of the laser beam 20, is preferably 10 to 30 μm from the viewpoint of narrowing the pitch of laser processing.
The scanning speed of the laser beam 20 is preferably 1000 to 3000 mm / sec from the viewpoint of increasing the laser processing speed.

A dry film may be provided on the upper surface or the lower surface of the printed circuit board 1 during laser processing. This makes it possible to prevent debris generated during laser processing from directly adhering to the upper surface or the lower surface of the original substrate 10. Debris can be easily removed by removing the dry film after laser processing.

(Laser processing equipment)
Next, an example of the laser processing apparatus used in the laser processing step S13 will be described. The laser processing apparatus 200 irradiates the original substrate 10 provided with the first metal layer 12 and the second metal layer 13 on the upper surface and the lower surface of the base material 11 of the printed circuit board 1 with laser light 20 to penetrate in a broad sense. It is a device that forms a hole. Further, the original substrate 10 is provided with a second metal layer removing region 23 in a region where the laser beam 20 is to be irradiated.

The laser processing apparatus 200 includes at least a laser light source 210 that emits laser light 20, a stage 250, and an optical system that guides the laser light 20 emitted from the laser light source 210 to the original substrate 10 mounted on the stage 250. It has a scanning unit that relatively moves the original substrate 10 placed on the stage 250 and the condensing point of the laser beam 20, and a control unit that controls the operation of the scanning unit. Hereinafter, each component will be described.

The laser light source 210 emits a laser beam 20 for irradiating the original substrate 10. The type of laser used as the laser light source 210 is not particularly limited, but is appropriately selected depending on the type of the original substrate 10 and the like. Examples of lasers include fiber lasers and the like.

In this example, the telescope optical system 220 and the fθ lens 240 are provided as the optical system, and a mirror or the like is appropriately used. As a scanning unit, a stage 250 and a galvano scanner 230 are provided, and an XY stage controller 270 and a Z controller 280 for driving these are also included. A computer 290 is provided as a control unit.
In addition, the laser processing apparatus 200 may further include an AF camera 260 or the like so as to have an automatic aiming system for locating the condensing point of the laser beam 20 at a desired position in the original substrate 10. good.

The laser light source 210 emits a laser beam 20 having a predetermined wavelength. As described above, the type of laser used as the laser light source 210 is appropriately selected according to the type of the original substrate 10 to be processed and the like.

The telescope optical system 220 optimizes the beam diameter of the laser beam 20 emitted from the laser light source 210 in order to obtain a preferable processed shape.

The galvano scanner 230 changes the traveling direction of the laser beam 20 optimized by the telescope optical system 220 based on the instruction of the computer 290. The laser beam 20 whose traveling direction is controlled by the galvano scanner 230 is condensed in the original substrate 10 by the fθ lens 240 which is a condenser lens. By combining the galvano scanner 230 and the fθ lens 240 in this way, it is possible to scan the condensing point of the laser beam 20 at a constant speed along the outer edge of the planned opening region 24.

The stage 250 has a mounting table on which the original substrate 10 is mounted, and a drive mechanism capable of moving the mounting table. The drive mechanism can move the mounting table in the X-axis or Y-axis direction, or rotate the mounting table around the X-axis or the Y-axis. The original substrate 10 on the stage 250 can be moved in the XY axis direction by this drive mechanism.

The AF camera 260 is a camera with an AF (autofocus) function for acquiring the surface profile of the laser-processed portion of the original substrate 10. The acquired profile is output to the computer 290.

Based on the instructions of the computer 290, the XY stage controller 270 moves the stage 250 in the XY axis direction so that the condensing point of the laser beam 20 is located at the outer edge of the opening formation planned region 24 of the original substrate 10.

The Z controller 280 moves the fθ lens 240 in the Z-axis direction so that the focusing point of the laser beam 20 is located in the original substrate 10 based on the instruction of the computer 290.

The computer 290 is connected to a laser light source 210, a galvano scanner 230, an AF camera 260, an XY stage controller 270 and a Z controller 280, and controls each of these parts comprehensively. For example, the computer 290 controls the AF camera 260 and the XY stage controller 270 to acquire the surface profile of the original substrate 10. Further, the computer 290 controls the galvano scanner 230 and the Z controller 280 to scan the laser beam 20 so as to make a plurality of orbits along the outer edge of the region for forming the opening. Further, the computer 290 controls the XY stage controller 270 to move the stage 250 so that the outer edge of the planned opening region 24 can be irradiated with the laser beam 20.

Next, as the laser processing step S13, a procedure for forming the opening 15 in the original substrate 10 by using the laser processing apparatus 200 will be described.
First, the original substrate 10 is placed on the mounting table of the stage 250, and the surface profile of the original substrate 10 is acquired by the AF camera 260 and the XY stage controller 270.

Next, after the original substrate 10 is moved to a predetermined position by the XY stage controller 270, the laser light 20 is emitted from the laser light source 210 to irradiate the original substrate 10 with the laser light 20. At this time, by changing the traveling direction of the laser beam 20 by the galvano scanner 230, the laser beam 20 is scanned so as to orbit a plurality of times along the outer edge of the region 24 where the opening is to be formed. Further, the laser beam 20 is scanned so that the irradiation interval between the laps at each point on the outer edge of the region 24 where the opening is to be formed is preferably 5 milliseconds or more. For example, the scanning of the laser beam 20 is stopped for a predetermined time for each round so that the irradiation interval between the rounds at each point on the outer edge of the region 24 where the opening is to be formed is 5 milliseconds or more. By irradiating the laser beam 20 in this way, the outer edge of the region 24 where the opening is planned to be formed is formed in the through groove 25 reaching the back surface of the original substrate 10 while suppressing the occurrence of undesired thermal damage such as charring and scooping. Can be formed along. When forming a plurality of openings 15 in the original substrate 10, the original substrate 10 may be moved by the XY stage controller 270, and then the above steps may be repeated.

In the plating step S14, the printed circuit board 1 after forming the opening 15 is plated to continuously cover the inner side surfaces of the first metal layer 12, the second metal layer 13, and the opening 15. This is a step of forming the third metal layer 14. By forming the third metal layer 14, the first metal layer 12 which is the wiring pattern on the upper surface side of the printed circuit board 1 and the second metal layer 13 which is the wiring pattern on the lower surface side are connected to each other through the opening 15. Can be electrically connected.

The third metal layer 14 may use a metal different from that of the first metal layer 12 and the second metal layer 13, but it is preferable to use the same kind of metal. For example, when Cu or a Cu alloy is used as the first metal layer 12 and the second metal layer 13, it is preferable to perform a Cu plating treatment to form the third metal layer 14. By using the same kind of metal as the first metal layer 12 and the second metal layer 13 as the third metal layer 14, the bondability between these metal layers can be improved.

The wiring pattern forming step S15 is a step of forming a predetermined wiring pattern by etching the first metal layer 12, the second metal layer 13, and the third metal layer 14. A mask is applied to the area to be left as a wiring electrode, and the first metal layer exposed from the mask is an etching solution according to the type of metal used as the first metal layer 12, the second metal layer 13, and the third metal layer 14. 12, The wiring pattern can be formed by removing the second metal layer 13 and the third metal layer 14.

In the present embodiment, in FIGS. 6A to 6C, in each region sandwiched by the vertically long slit-shaped openings 15, the wiring electrodes 16 are laterally separated into two regions on the upper surface side and the lower surface side. And the wiring electrode 17 is formed. On the upper surface side, the wiring electrode 16 has an element mounting portion 16a for joining with one electrode of the light emitting element to be mounted, and the wiring electrode 17 is for joining with the other electrode of the light emitting element to be mounted. It has an element mounting portion 17a. Further, on the lower surface side which is the mounting surface when mounting on another circuit board, the wiring electrode 16 and the wiring electrode 17 are provided with a larger separation distance than the upper surface side.

Further, in the printed circuit board 1 in the present embodiment, each region partitioned by the boundary line 61 partitioned in the vertical direction and the boundary line 62 partitioned in the horizontal direction is a mounting substrate for mounting one light emitting element. Used as. That is, the printed circuit board 1 is manufactured in the form of an aggregate substrate in which a plurality of mounting substrates for a light emitting device are assembled. Although details will be described later, a light emitting device can be manufactured by mounting a light emitting element on the element mounting portions 16a and 17a of each region and dividing the light emitting element along the boundary lines 61 and 62.

The wiring pattern is not limited to this, and can be formed according to the purpose. For example, in addition to the light emitting element, a wiring pattern may be formed so that a circuit can be configured in consideration of mounting a protective element. Further, the printed circuit board 1 is not limited to a collective circuit board in which mounting boards for manufacturing a plurality of light emitting devices are assembled, and may be used for manufacturing one light emitting device or the like as a whole.

By performing the above steps, the printed circuit board 1 can be manufactured.

<Modification example>
Next, a modified example of the method for manufacturing a printed circuit board will be described with reference to FIGS. 7A and 7B.
FIG. 7A is a cross-sectional view showing a first modification of the etching process in the method for manufacturing a printed circuit board according to the first embodiment. FIG. 7B is a cross-sectional view showing a second modification of the etching process in the method for manufacturing a printed circuit board according to the first embodiment.

(First modification)
In the method for manufacturing a printed circuit board according to the first modification, in the etching step S12 described above, the second metal layer removing region 23 is formed on the second metal layer 13 with respect to the laser light irradiation scheduled region 21 and the region in the vicinity thereof in plan view. In addition to the above, the first metal layer removing region 22 is formed on the first metal layer 12 on the upper surface side. Other steps are performed in the same manner as the method for manufacturing a printed circuit board according to the first embodiment described above.

The number of scans of the laser beam 20 in the laser processing step S16 can be further reduced by removing the first metal layer 12 in advance in addition to the second metal layer 13 in the laser beam irradiation planned region 21 and the region in the vicinity thereof. can.

In this modification, the first metal layer removing region 22 is formed so as to overlap the second metal layer removing region 23 in a plan view, but the present invention is not limited to this. If the same conditions as those of the second metal layer removing region 23 are satisfied, it is not necessary to form the first metal layer removing region 22 and the second metal layer removing region 23 so as to completely overlap each other in a plan view.

(Second modification)
In the method for manufacturing a printed circuit board according to the second modification, in the etching step S12 described above, the second metal layer removing region 23 is formed in the planned laser beam irradiation region 21 and the vicinity region within a predetermined separation distance d in a plan view. It is something to do. That is, the second metal layer 13 is left unremoved in the region inside the region 24 in which the opening is to be formed. Other steps are performed in the same manner as the method for manufacturing a printed circuit board according to the first embodiment described above.

Also in the second modification, the number of scans of the laser beam 20 is the same as that of the first embodiment shown in FIGS. 3A and 3B in order to remove the second metal layer 13 in the region 21 scheduled to be irradiated with the laser beam and the region in the vicinity thereof in advance. It can be reduced as well. Further, since the second metal layer 13 is left in the region inside the region 24 where the opening is planned to be formed, the excess heat energy accumulated in the base material 11 during the laser processing is left behind in the second metal layer 13. It becomes possible to dissipate effectively through the base material 11, and it is possible to suppress the occurrence of thermal damage in the laser-processed portion of the base material 11.

Further, in the first modification, even when the first metal layer 12 on the upper surface side is removed, only the laser light irradiation scheduled region 21 and the vicinity region within a predetermined separation distance d are the first as in the second modification. 1 The metal layer removal region 22 may be used.

<Second Embodiment>
[Light emitting device and its manufacturing method]
Next, the light emitting device and the manufacturing method thereof according to the second embodiment will be described with reference to FIGS. 8 to 11B.
FIG. 8 is a flowchart showing a procedure of a method for manufacturing a light emitting device according to a second embodiment. FIG. 9A is a plan view showing a light emitting element mounting process in the method for manufacturing a light emitting device according to a second embodiment. FIG. 9B is a cross-sectional view showing a light emitting element mounting process in the method for manufacturing a light emitting device according to a second embodiment, and shows a cross section taken along the line IXB-IXB of FIG. 9A. FIG. 10A is a plan view showing a light-shielding member forming step in the method for manufacturing a light emitting device according to a second embodiment. FIG. 10B is a cross-sectional view showing a light-shielding member forming step in the method for manufacturing a light emitting device according to a second embodiment, and shows a cross-sectional view taken along the line XB-XB of FIG. 10A. FIG. 11A is a plan view showing a translucent member forming step in the method for manufacturing a light emitting device according to a second embodiment. FIG. 11B is a cross-sectional view showing a translucent member forming step in the method for manufacturing a light emitting device according to a second embodiment, and shows a cross section taken along the line XIB-XIB of FIG. 11A.

[Configuration of light emitting device]
The light emitting device 100 according to the second embodiment is configured by using the printed circuit board 1 according to the first embodiment as a mounting board and mounting the light emitting element 3 on the printed circuit board 1. Further, the light emitting device 100 is sealed with a sealing member 5 including a light shielding member 51 that covers the side surface of the light emitting element 3 and a translucent member 52 that covers the upper surface of the light emitting element 3.
The detailed configuration of the light emitting device 100 will be described together with the manufacturing method thereof.

[Manufacturing method of light emitting device]
The method for manufacturing a light emitting device according to the second embodiment includes a printed circuit board preparation step S21, a light emitting element mounting step S22, a sealing step S23, and an individualization step S24. Further, the sealing step S23 includes a light-shielding member forming step S231 and a translucent member forming step S232.

The printed circuit board preparation step S21 is a step of preparing the printed circuit board 1 by the method for manufacturing a printed circuit board according to the first embodiment or a modification thereof.
As described above, the printed circuit board 1 prepared in the present embodiment has the first metal layer 12 and / and the second metal arranged in the laser light irradiation planned region before the opening 15 is formed by laser processing. The layer 13 is removed by etching. Therefore, even if the first metal layer 12 and the second metal layer 13 are formed to have a thick film thickness, it is possible to suppress an increase in the time required for laser processing. Further, by using the thick first metal layer 12 and the second metal layer 13, the thermal resistance of the wiring pattern can be lowered, and the heat from the light emitting element 3 mounted on the wiring pattern can be efficiently transferred. It is possible to dissipate heat and suppress the temperature rise of the light emitting element 3. As a result, the luminous efficiency of the light emitting element 3 can be increased and the light flux of the light emitting device 100 can be improved.

The light emitting element mounting step S22 is a step of mounting the light emitting element 3 on the printed circuit board 1 which is the mounting board of the light emitting device 100. The light emitting element 3 is not particularly limited, but for example, a semiconductor light emitting device such as an LED (light emitting diode) using a nitride semiconductor can be used. In the present embodiment, the light emitting element 3 is provided with an n-side electrode 31 and a p-side electrode 32 as a pair of electrodes on one surface side thereof, and the n-side electrode 31 and the p-side electrode 32 are soldered or anisotropic. A bonding member 4 having conductivity such as a conductive adhesive is used to bond to the element mounting portions 16a and 17a of each element region of the printed circuit board 1.

The mounting form of the light emitting element 3 is not particularly limited, and in addition to the flip chip mounting as in the present embodiment, the light emitting element 3 is mounted face-up using a die bond resin, and a conductive wire is mounted. It may be used to electrically connect to the wiring electrodes 16 and 17.

The sealing step S23 is a step of sealing the light emitting element 3 by using the sealing member 5. As described above, the light-shielding member forming step S231 and the translucent member forming step S232 are included.

The light-shielding member forming step S231 is a step of forming the light-shielding member 51 so as to cover the side surface of the light emitting element 3. The light-shielding member 51 may be a light-reflecting member made of a light-reflecting material or a light-absorbing member made of a light-absorbing material. When a light-reflecting member is used as the light-shielding member 51, the light emitted from the light-emitting element 3 can be efficiently emitted from the upper surface side of the light-emitting device 100, so that the light extraction efficiency can be improved. Further, when the light absorbing member is used as the light blocking member 51, the luminance contrast between the light emitting surface and the non-light emitting surface of the light emitting device 100 can be increased.

As the light-reflecting material, for example, a white resin in which a white pigment such as TiO ₂ is contained in a translucent resin such as a silicone resin or an epoxy resin can be used. Further, as the light-absorbing material, a black resin containing a black pigment such as carbon black in the above-mentioned translucent resin can be used.
The light-shielding member 51 can be formed of these materials by a molding method using a mold, various coating methods such as a screen printing method, and the like.

The translucent member forming step S232 is a step of forming the translucent member 52 so as to cover the upper surface of the light emitting element 3 and the upper surface of the light-shielding member 51. The light emitting element 3 mounted on the printed circuit board 1 is sealed by a sealing member 5 including a light-shielding member 51 that covers the side surface and a translucent member 52 that covers the upper surface.

As the translucent member 52, a resin having the same translucency as that used for the light-shielding member 51 can be used. Further, the translucent member 52 may contain particles of a phosphor that absorbs a part or all of the light from the light emitting element 3 and converts it into light having a different wavelength.
The translucent member 52 can be formed by a molding method using a mold, various coating methods, or the like. Further, the plate-shaped translucent member 52 may be attached to the upper surface of the light emitting element 3 and the upper surface of the light-shielding member 51.

In the present embodiment, the sealing member 5 is configured by the light-shielding member 51 and the translucent member 52, but the configuration and manufacturing method of the sealing member 5 are not limited to this. For example, the material used for the translucent member 52 may be supplied so as to cover the entire light emitting element 3 by a potting method or the like to form the sealing member 5.
Further, the sealing member 5 may not be provided, or a member covering a part of the light emitting element 3 may be provided instead of the sealing member 5.

The individualization step S24 is a step of individualizing the light emitting device 100 by dividing the printed circuit board 1 which is an assembly substrate into each element region.
In the present embodiment, the light emitting device 100 can be individualized by cutting the printed circuit board 1 and the sealing member 5 along the boundary line 61 by a dicing method or the like. In the printed circuit board 1, since the element regions adjacent to each other in the lateral direction are originally separated by the opening 15 provided along the boundary line 62, the cutting work along the boundary line 62 is unnecessary.

By performing the above steps, the light emitting device 100 according to the second embodiment can be manufactured.

The printed circuit board, the light emitting device, and the method for manufacturing the same according to the present invention have been specifically described above in terms of the mode for carrying out the invention, but the gist of the present invention is not limited to these descriptions, and the patent. It must be broadly interpreted based on the statement of claims. Needless to say, various changes and modifications based on these descriptions are also included in the gist of the present invention.

The light emitting device according to the embodiment of the present disclosure can be used for a lighting device, an in-vehicle light emitting device, and the like.

1 Printed circuit board 10 Original board 11 Base material 111 Resin layer 112 Reinforcing material 112a Warp 112b Weft 12 First metal layer 13 Second metal layer 14 Third metal layer 15 Opening (through hole)
16,17 Wiring electrode (wiring pattern)
16a, 17a Element mounting part 18 Hole part 19 Separated part 20 Laser light 21 Laser light irradiation area 22 First metal layer removal area 23 Second metal layer removal area 24 Opening planned area 25 Through groove 3 Light source 31 n Side electrode 32 p Side electrode 4 Joining member 5 Sealing member 51 Light-shielding member 52 Translucent member 61, 62 Boundary line 100 Light emitting device 200 Laser processing device 210 Laser light source 220 Telescope optical system 230 Galvano scanner 240 fθ lens 250 XY Stage 260 AF Camera 270 XY Stage Controller 280 Z Controller 290 Computer

Claims (17)

The original substrate comprising a plate-shaped base material having an insulating property, a first metal layer provided on one surface of the base material, and a second metal layer provided on the other surface of the base material, said. A laser processing step of forming a through hole penetrating in the thickness direction in the original substrate by irradiating a laser beam from the first metal layer side is included.
Prior to the laser processing step, there is an etching step of removing the second metal layer arranged in the area to be irradiated with the laser beam by etching.
A method for manufacturing a printed circuit board, which leaves the second metal layer inside the region where an opening is planned to be formed in the etching step. The original substrate comprising a plate-shaped base material having an insulating property, a first metal layer provided on one surface of the base material, and a second metal layer provided on the other surface of the base material, said. A laser processing step of forming a through hole penetrating in the thickness direction in the original substrate by irradiating a laser beam from the first metal layer side is included.
In the laser processing step, the irradiation interval between the laps at each point to be irradiated with the laser beam is set to 5 milliseconds or more, and the scanning is performed a plurality of times so as to circulate, and the through hole is formed in a slit shape by the annular through groove. ,
Prior to the laser processing step, there is an etching step of removing the second metal layer arranged in the area to be irradiated with the laser beam by etching.
A method for manufacturing a printed circuit board, comprising a step of providing a dry film on a first metal layer and a second metal layer after the etching step and before the laser processing step . The method for manufacturing a printed circuit board according to claim 1 or 2, wherein in the etching step, the second metal layer is removed so as to be separated from the planned irradiation region of the laser beam by a predetermined distance or more. The method for manufacturing a printed circuit board according to claim 3, wherein the predetermined distance away from the planned irradiation area of the laser beam is 10 μm or more and 500 μm or less. The method for manufacturing a printed circuit board according to any one of claims 1 to 4, further removing the first metal layer arranged in the area to be irradiated with the laser beam in the etching step. The method for manufacturing a printed circuit board according to claim 5, wherein in the etching step, the first metal layer is removed so as to be separated from the planned irradiation region of the laser beam by a predetermined distance or more. The method for manufacturing a printed circuit board according to any one of claims 1 to 6, wherein in the laser processing step, the laser light is irradiated along the outer edge of the region where the through hole is to be formed. The material constituting the base material is selected from the group consisting of epoxy resin, polyimide resin, polyethylene terephthalate resin, polyethylene naphthalate resin, bismaleimide triazine resin, phenol resin, silicone resin, modified silicone resin and epoxy-modified silicone resin. The method for manufacturing a printed substrate according to any one of claims 1 to 7, which is one or more resins. The method for producing a printed circuit board according to claim 8, wherein the substrate contains one or more reinforcing materials selected from the group consisting of glass fiber, ceramic fiber, carbon fiber and aramid fiber. The metal constituting the first metal layer and the second metal layer is one or more metals selected from the group consisting of Cu, Ag, Au, Ni and Al, respectively, or these metals as main components. The method for manufacturing a printed substrate according to any one of claims 1 to 9, which is an alloy containing the mixture. The method for manufacturing a printed circuit board according to any one of claims 1 to 10, wherein the thickness of the first metal layer is 1 μm or more and 18 μm or less. The method for manufacturing a printed circuit board according to any one of claims 1 to 11, wherein the thickness of the base material is 200 μm or more and 500 μm or less. In the laser processing process
The laser light has an oscillation wavelength of 250 nm or more and 2000 nm or less, a power of 10 W or more and 60 W or less, a frequency of 100 kHz or more and 3000 kHz or less, and a pulse width of 10 picoseconds or more and 100 nanoseconds or less. When the pulse energy is 3 μJ or more, the fluence on the surface of the original substrate is 3 J / cm2 or more, the fluence at the condensing point is 10 J / cm2 or more, and the same position in the plan view of the original substrate is repeatedly irradiated. The method for manufacturing a printed substrate according to any one of claims 1 to 12, wherein the irradiation interval is 5 msec or more and the scanning speed is 1000 mm / sec or more and 3000 mm / sec or less. In the laser processing process
The method for manufacturing a printed circuit board according to any one of claims 1 to 13, wherein the width of the laser beam is 10 μm or more and 30 μm or less. A claim comprising a plating step of forming a third metal layer that continuously covers the first metal layer, the second metal layer, and the inner side surface of the through hole by plating after the laser processing step. The method for manufacturing a printed circuit board according to any one of 1 to 14. The method for manufacturing a printed circuit board according to claim 15, further comprising a step of forming a wiring pattern by etching the first metal layer, the second metal layer, and the third metal layer after the plating step. A step of preparing a printed circuit board according to the method for manufacturing a printed circuit board according to claim 16.
A method for manufacturing a light emitting device, comprising a step of mounting a light emitting element on the printed circuit board so as to be electrically connected to the wiring pattern.

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