Method for manufacturing a wiring board, and wiring board
By forming non-overlapping grooves on the laminate surfaces using blades or laser beams, the method addresses the issue of laminate peeling and cracking in wiring boards, enhancing their reliability through deformation absorption.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DISCO CORP
- Filing Date
- 2024-12-09
- Publication Date
- 2026-06-19
AI Technical Summary
The conventional dicing method for manufacturing wiring boards results in a high defective rate due to laminate peeling off or cracking from the core board during temperature cycle tests.
A method involving forming grooves on the laminate surfaces and using blades or laser beams to create non-overlapping grooves and division lines that do not reach the core substrate, ensuring the laminate remains intact during division.
This approach effectively prevents laminate deformation and peeling, reducing the defect rate of the wiring boards by absorbing deformation and preventing cracking.
Smart Images
Figure 2026100759000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a method for manufacturing a wiring board formed by disposing a laminate on a core board.
Background Art
[0002] Conventionally, as disclosed in Patent Document 1, for example, as one of a printed board or a package substrate, a core board (glass board) made of an inorganic material and an insulating layer (resin layer) disposed on the core board and having at least one wiring layer formed therein are laminated to form a wiring board (laminate). This type of wiring board is used, for example, as a 'core board for package' (relay board) for mounting different types of semiconductor chips on both sides and connecting both chips. Generally, a wiring board is manufactured by dicing a single material board into required dimensions with a known dicing device (cutting device) and separating it into individual pieces.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, when a temperature cycle test (TCT: Temperature Cycling Test) is performed on a wiring board diced into required dimensions and separated into individual pieces by a normal dicing method, there is a problem that the defective rate of the wiring board increases because the laminate peels off from the core board or the laminate cracks (back cracks), and this has been an issue.
[0005] In view of the above problems, the present invention proposes a new technology for reducing the defective rate of a wiring board in which a laminate is formed on a core board.
Means for Solving the Problems
[0006] The problems that this invention aims to solve are as described above, and the means for solving these problems will now be explained.
[0007] According to one aspect of the present invention, a method for manufacturing a wiring board in which a laminate is formed on a first surface side and / or a second surface side of a core substrate, comprising at least a groove forming step of forming two grooves having a predetermined interval along the division line with a first blade having a first thickness from the first surface side and / or the second surface side, and a division step of forming division grooves in the core substrate along the division line between the two grooves to form individual wiring boards.
[0008] Furthermore, according to one aspect of the present invention, in the groove formation step, the two grooves do not reach the core substrate.
[0009] Furthermore, according to one aspect of the present invention, the two machined grooves and the divided grooves are formed so as not to overlap.
[0010] Furthermore, according to one aspect of the present invention, the division step includes at least a division step of forming a division groove between the two processing grooves with a second blade having a width smaller than a predetermined interval between the two processing grooves, which divides the core substrate along the planned division line.
[0011] Furthermore, according to one aspect of the present invention, the division step comprises at least a division step of irradiating a laser beam along the planned division line between the two processing grooves to form a division groove for dividing the core substrate.
[0012] Furthermore, according to one aspect of the present invention, a method for manufacturing a wiring board in which a laminate is formed on the first surface side and / or the second surface side of a core substrate, comprising at least a groove forming step of irradiating a first laser beam from the first surface side and / or the second surface side along the planned division line to form two processing grooves having a predetermined interval, and a division step of forming a division groove between the two processing grooves to divide the wiring board along the planned division line.
[0013] Furthermore, according to one aspect of the present invention, in the groove formation step, the two grooves form grooves that expose the core substrate.
[0014] Furthermore, according to one aspect of the present invention, the two machined grooves and the divided grooves are formed so as not to overlap.
[0015] Furthermore, according to one aspect of the present invention, the division step includes at least a division step of forming a division groove between the two processing grooves with a second blade that is narrower than a predetermined interval between the two processing grooves, thereby dividing the core substrate along the planned division line.
[0016] Furthermore, according to one aspect of the present invention, the division step comprises at least a division step of irradiating a second laser beam along the planned division line between the two processing grooves to form a division groove that divides the core substrate.
[0017] Furthermore, according to one aspect of the present invention, there is a wiring board in which a laminate is formed on the first surface side and / or the second surface side of a core substrate, wherein a processing groove that does not reach the core substrate is formed on the outer peripheral edge of the laminate, and a wall portion made of the laminate is formed outside the processing groove.
[0018] Furthermore, according to one aspect of the present invention, the laminate includes a wiring layer and / or an insulating layer. [Effects of the Invention]
[0019] The present invention has the following effects. That is, according to one aspect of the present invention, it is possible to effectively prevent defects such as deformation of the laminate progressing and peeling from the core substrate, or the laminate cracking (back cracking), and reduce the defect rate of the wiring board.
Brief Description of the Drawings
[0020] [Figure 1] (A) is a perspective view showing an example of a material substrate. (B) is an enlarged cross-sectional view of a part of the material substrate. [Figure 2] It is a flowchart showing the steps included in the manufacturing method. [Figure 3] (A) is a diagram for explaining the step of forming two processing grooves on the first surface side. (B) is a diagram for explaining the step of forming two processing grooves on the second surface side. [Figure 4] (A) is a diagram for explaining the dividing step. (B) is a diagram showing the state where the dividing groove is formed. [Figure 5] (A) is a diagram showing the schematic of the individual wiring boards. (B) is a diagram showing the cross-section of the individual wiring boards. [Figure 6] (A) is a diagram for explaining the step of forming two processing grooves on the first surface side by laser ablation processing. (B) is a diagram for explaining the step of forming two processing grooves on the second surface side by laser ablation processing. [Figure 7] It is a diagram for explaining an example of performing the dividing step by laser ablation processing.
Embodiments for Carrying Out the Invention
[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1(A) is a perspective view schematically showing a configuration example of a material substrate 1 before being divided into control boards, and FIG. 1(B) is an enlarged cross-sectional view of a part of the material substrate 1.
[0022] As shown in Figure 1(A), the material substrate 1 is formed by forming laminates 15a and 15b on both sides of a plate-shaped glass substrate 11, and is configured as a rectangular plate-shaped substrate overall. The size of the material substrate 1 is, for example, 500 mm x 500 mm, but the size is not particularly limited, and the material substrate 1 may also be disc-shaped.
[0023] The glass substrate 11 is, for example, alkali-free glass and functions as a so-called core substrate.
[0024] As shown in Figure 1(B), a laminate 15a, 15b is formed on the first surface (front) 11a and the second surface (back) 11b opposite to the first surface 11a of the glass substrate 11, each consisting of multiple layers (films) stacked on top of each other. These laminates 15a, 15b include, for example, a wiring layer 17 made of a conductor such as metal and an insulating layer 19 made of an insulator such as resin, with the insulating layer 19 insulating the spaces between adjacent wiring layers 17.
[0025] A through-hole 11c is formed in the glass substrate 11, penetrating from the first surface 11a to the second surface 11b. An electrode 21 made of a conductor such as metal is embedded in the through-hole 11c, and the wiring layer 17 on the first surface 11a side and the wiring layer 17 on the second surface 11b side are connected via the electrode 21.
[0026] In this embodiment, a material substrate 1 having laminates 15a and 15b on both the first surface 11a and the second surface 11b of the glass substrate 11 is illustrated, but the laminates 15a and 15b may be provided on only one of the first surface 11a and the second surface 11b. In that case, through holes 11c and electrodes 21, etc., can be omitted. Furthermore, there are no particular restrictions on the configuration and formation methods of the laminates 15a and 15b (wiring layer 17, insulating layer 19), through holes 11c, electrodes 21, etc. In addition to using the glass substrate 11 as the core substrate, a substrate made of a semiconductor material such as silicon, or an organic substrate formed by impregnating glass material fibers with a resin such as epoxy may also be used as the core substrate.
[0027] As shown in Figure 1(A), multiple wiring boards 3 (core boards for packages) are manufactured by dividing the material substrate 1, which is configured as described above, along the division lines 13. The division lines 13 (streets) are, for example, set up in a grid pattern on the material substrate 1, and are divided along the division lines 13 through the steps described later, forming individual rectangular wiring boards 3. The size of the wiring board 3 is, for example, 50mm x 50mm, but the size is not particularly limited.
[0028] Next, we will explain a method for manufacturing a wiring board 3 by dividing the material substrate 1 shown in Figure 1(A). Figure 2 is a flowchart showing the steps included in the manufacturing method.
[0029] <Processing groove formation step> As shown in Figures 3(A) and 3(B), the step involves forming two processing grooves with a predetermined interval K along the division line 13 using first blades B1, B1 having a first thickness from the first surface side and / or the second surface side of the glass substrate 11.
[0030] Specifically, as shown in Figure 3(A), first, the material substrate 1 is fixed to the tape 41 by attaching the other side 1b to the tape 41 so that one side 1a of the material substrate 1 is exposed upwards. Next, the first blades B1, B1 are used to cut into the laminate 15a on the first side 11a of the glass substrate 11, forming two processing grooves M1, M1 in the laminate 15a.
[0031] Here, the first blades B1, B1 are disc-shaped cutting blades made of abrasive grains such as artificial diamond and a binder, and they cut the surface of one side 1a of the material substrate 1 by rotating at a predetermined rotational speed.
[0032] The first blades B1, B1 are mounted on a spindle (not shown) at a predetermined distance K apart, forming a so-called multi-blade system, and are configured to simultaneously form two machining grooves M1, M1.
[0033] Alternatively, instead of using a multi-blade system, it may be possible to use only one first blade B1 and process one line at a time to sequentially form two processing grooves M1, M1.
[0034] Furthermore, the two processing grooves M1, M1 are not to reach the glass substrate 11 (core substrate). This prevents the first blades B1, B1 from reaching the surface of the glass substrate 11 (first surface 11a, second surface 11b) and forming cutting marks on the surface, thereby preventing damage to the surface and, consequently, preventing a decrease in the strength of the glass substrate 11. In addition, the laminate 15a remains between the bottom surface of the two processing grooves M1, M1 and the glass substrate 11, and as will be described in more detail later, when the wall portion 16 (Figure 5(B)) is formed later, this prevents the wall portion 16 (Figure 5(B)) from separating from the glass substrate 11 and falling off, becoming foreign matter.
[0035] Furthermore, the two machining grooves M1, M1 are formed so as not to overlap with the dividing groove M3 (Figure 4(A)) formed in a later dividing step.
[0036] Specifically, the predetermined distance K between the two machined grooves M1, M1 is formed to be wider than the divided groove M3 shown in Figure 4(A), which is machined later. In other words, the divided groove M3 (Figure 4(B)) is formed between the two machined grooves M1, M1.
[0037] As shown in Figure 1(A), two processing grooves M1, M1 are formed on one side 1a of the material substrate 1 for all planned division lines 13, as shown in Figure 3(A). Then, the material substrate 1 is peeled off the tape 41, and as shown in Figure 3(B), the material substrate 1 is inverted and one side 1a is attached to another tape 42, fixing the material substrate 1 to the tape 42. Next, similar to Figure 3(A), the first blades B1, B1 are used to cut into the laminate 15b on the second side 11b of the glass substrate 11, as shown in Figure 3(B), forming two processing grooves M2, M2 in the laminate 15b.
[0038] The two processed grooves M2, M2 in this laminate 15b are formed with a predetermined interval K, similar to the already formed processed grooves M1, M1, and do not reach the glass substrate 11 (core substrate). Furthermore, they are made so as not to overlap with the dividing groove M3 (Figure 4(A)) formed in a later dividing step.
[0039] <Splitting Steps> As shown in Figures 4(A) and 4(B), the step involves forming a dividing groove M3 in the glass substrate 11 (core substrate) along the planned dividing line 13 between two processing grooves, thereby forming individual wiring boards 3.
[0040] Specifically, as shown in Figure 3(B), after processing two processing grooves M2, M2 in the laminate 15b on the second surface 11b side of the glass substrate 11, as shown in Figure 4(A), the glass substrate 11 is divided along the planned division line 13 between the two processing grooves M2, M2 using a second blade B2 that is narrower than the predetermined interval K (Figure 3(B)) between the two processing grooves M2, M2.
[0041] The second blade B2 is mounted on a spindle (not shown) and rotates, and is a disc-shaped cutting blade made of abrasive grains such as artificial diamond and a binder, and rotates at a predetermined rotational speed.
[0042] As shown in Figure 4(A), the second blade B2 cuts into the material substrate 1 so as to penetrate the laminate 15b on the second surface 11b side, the glass substrate 11, and the laminate 15a on the first surface 11a side, forming a dividing groove M3 that divides the material substrate 1.
[0043] As described above, as shown in Figure 3(B), a dividing groove M3 is formed along the planned dividing line 13 on the material substrate 1, thereby forming individual wiring boards 3 as shown in Figures 5(A) and 5(B).
[0044] Furthermore, although the above explanation describes performing the groove formation step using the first blades B1, B1 (Figure 3(A)), as shown in Figure 6(A), the first laser beam L1 may be irradiated along the planned division line 13 to form two grooves M4, M4 with a predetermined interval K.
[0045] Specifically, on the laminate 15a on the first surface 11a side of the glass substrate 11, a laser beam L1 is irradiated from the laser beam irradiation unit 61 of the laser processing apparatus at a position half a predetermined distance K away from the planned division line 13 to perform laser ablation processing, thereby forming one processing groove M4 parallel to the planned division line 13. Next, the laser beam irradiation unit 61 is moved by the predetermined distance K to form another processing groove M4 parallel to the planned division line 13, thereby forming processing grooves M4, M4 on both sides of the planned division line 13. Alternatively, two laser beam irradiation units may be used to simultaneously form two processing grooves, or one laser beam may be split into two laser beams to simultaneously form two processing grooves.
[0046] After forming the processed grooves M4, M4 on the laminate 15a on the first surface 11a side, the front and back sides of the material substrate 1 are reversed, and as shown in Figure 6(B), processed grooves M5, M5 are similarly formed on the laminate 15b on the second surface 11b side.
[0047] The processed grooves M4 and M5 shown in Figures 6(A) and 6(B) are formed in such a way that the first surface 11a and the second surface 11b of the glass substrate 11 are exposed, and a portion of the laminate 15a and 15b may also be left intact. Leaving a portion of the laminate 15a and 15b intact prevents the wall portion 16 (Figure 5(B)) from separating from the glass substrate 11 and falling off, becoming foreign matter, as will be described in more detail later.
[0048] Furthermore, by exposing the first surface 11a and the second surface 11b of the glass substrate 11 in the processed grooves M4 and M5, it is possible to prevent delamination and cracking (back cracking) of the surrounding laminates 15a and 15b, starting from the laminates 15a and 15b remaining at the bottom of the processed grooves M4 and M5. Whether to expose the first surface 11a and the second surface 11b of the glass substrate 11 in the processed grooves M4 and M5, or not to expose them (leaving a portion of the laminates 15a and 15b), may be appropriately selected depending on the composition and thickness of the laminates 15a and 15b.
[0049] Furthermore, in the above embodiment, the division step was performed using a second blade B2 (Figure 4(A)), but as shown in Figure 7, a second laser beam L2 may be irradiated along the division line 13 to form division grooves M6 in the glass substrate 11 (core substrate) and form individual wiring boards 3.
[0050] Specifically, as shown in Figures 3(B) and 6(B), after processing two grooves M2 (Figure 3(B)) and M4 (Figure 6(B)) on the laminate 15b on the second surface 11b side of the glass substrate 11, a laser beam L2 is irradiated between the two grooves along the planned division line 13 to perform laser ablation processing, thereby forming a division groove M6 (Figure 7) and dividing the glass substrate 11. In addition to dividing the glass substrate 11 by the division groove M6 (Figure 7), a modified layer may be formed by irradiating the inside of the glass substrate 11 with a laser beam, and the substrate may be divided starting from the modified layer (stealth dicing®).
[0051] The present invention can be implemented in the manner described above. As shown in Figures 5(A) and 5(B), the processing grooves M1 and M2 are formed on the outer edges of the laminates 15a and 15b of the wiring board 3. These processing grooves M1 and M2 act as gaps that buffer the progression of deformation of the laminates 15a and 15b. In other words, on the outer edge of the rectangular wiring board 3, a wall portion 16 consisting of the laminates 15a and 15b is formed outside the processing grooves M2. Even if the wall portion 16 deforms during a temperature cycling test (TCT), the deformation is absorbed by the gaps in the processing grooves M1 and M2, preventing the progression of deformation of the laminates 15a and 15b at the processing grooves M1 and M2. This effectively prevents defects such as delamination from the glass substrate 11 (core substrate) or cracking (back cracking) of the laminates 15a and 15b, thereby reducing the defect rate of the wiring board 3. [Explanation of symbols]
[0052] 1. Substrate material 3 Wiring board 11 Glass substrate 11a 1st page 11b Side 2 11c through hole 13 planned division lines 15a Laminate 15b Laminate 17 Wiring layer 19. Insulating layer 21 electrodes 41 Tapes 42 tapes 61 Laser beam irradiation unit B1 First Blade B2 Second Blade K predetermined interval L1 laser beam L2 laser beam M1 Machining groove M2 machining groove M3 split groove M4 processing groove M5 processing groove M6 split groove
Claims
1. A method for manufacturing a wiring board in which a laminate is formed on the first surface and / or the second surface of a core substrate, A groove forming step in which a first blade having a first thickness forms two grooves at a predetermined interval along the planned division line from the first surface side and / or the second surface side, A division step in which a division groove is formed in the core substrate along the planned division line between the two processing grooves to form individual wiring boards, A method for manufacturing a wiring board having at least the following.
2. In the groove formation step, the two grooves do not reach the core substrate. The method for manufacturing a wiring board according to claim 1.
3. The two machined grooves and the divided grooves are formed so as not to overlap. The method for manufacturing a wiring board according to claim 1.
4. The division step involves forming a dividing groove between the two machining grooves with a second blade that is narrower than the predetermined spacing between the two machining grooves, to divide the core substrate along the planned division line. Having at least, A method for manufacturing a wiring board according to any one of claims 1 to 3.
5. The division step includes a division step in which a laser beam is irradiated between the two processing grooves along the planned division line to form a division groove that divides the core substrate, Having at least, A method for manufacturing a wiring board according to any one of claims 1 to 3.
6. A method for manufacturing a wiring board in which a laminate is formed on the first surface and / or the second surface of a core substrate, A groove forming step in which a first laser beam is irradiated from the first surface side and / or the second surface side along the planned division line to form two grooves having a predetermined interval between them, A division step in which a division groove is formed between the two processing grooves to divide the wiring board along the planned division line, A method for manufacturing a wiring board having at least the following.
7. In the groove formation step, the two grooves form grooves that expose the core substrate. The method for manufacturing a wiring board according to claim 6.
8. The two machined grooves and the divided grooves are formed so as not to overlap. The method for manufacturing a wiring board according to claim 6.
9. The division step involves forming a dividing groove between the two machining grooves with a second blade that is narrower than the predetermined spacing between the two machining grooves, to divide the core substrate along the planned division line. Having at least, A method for manufacturing a wiring board according to any one of claims 6 to 8.
10. The division step includes a division step in which a second laser beam is irradiated between the two processing grooves along the planned division line to form a division groove that divides the core substrate, Having at least, A method for manufacturing a wiring board according to any one of claims 6 to 8.
11. A wiring substrate in which a laminate is formed on the first surface side and / or the second surface side of a core substrate, A processing groove is formed on the outer edge of the laminate that does not reach the core substrate. A wiring board in which a wall portion made of the laminate is formed on the outside of the processed groove.
12. The laminate includes a wiring layer and / or an insulating layer. The wiring board according to feature 11.