Glass wiring board and method for manufacturing glass wiring board

Abstract

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a glass wiring board and a method of manufacturing the glass wiring board, and particularly relates to a glass wiring board in which a crack occurring in the glass wiring board is avoided and a method of manufacturing the glass wiring board.SOLUTION: The glass substrate (10) is provided with a through-hole section (13) formed in the thickness direction from a first surface section (11) to a second surface section (12) of the glass substrate (10), a conductive material (14) embedded in the through-hole section (13), and a resin film section (20) affixed to the first surface section (11) and the second surface section (12) of the glass substrate (10), respectively, and also with a glass cutout section (30) composed of a groove section (31) having a predetermined width formed in the first surface section (11) and the second surface section (12) of the glass substrate (10) and a concave section (32) joined to the groove section (31) and cut out in the width direction of the glass substrate (10) from the side end section of the glass substrate (10).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a glass wiring substrate and a method for manufacturing the same, and more particularly to a glass wiring substrate that avoids cracks occurring in the glass wiring substrate and a method for manufacturing the same. [Background technology]

[0002] Semiconductor elements, such as various types of memory, CPUs, and GPUs, mounted on circuit boards have terminals for electrical connection. The pitch of these connection terminals is typically several to several tens of times different from the pitch of the connection portions of the circuit board that are electrically connected to the semiconductor elements. Therefore, a relay substrate called an interposer is used to electrically connect the semiconductor elements and the circuit board. The semiconductor elements are mounted on one side of the interposer, and the circuit board is connected to the other side.

[0003] Organic resin materials have been used as materials for interposers. However, to improve the processing power of semiconductor elements and respond to higher integration, there is a demand for fine wiring formation in interposers. However, with interposers using conventional organic resin materials, the resin absorbs moisture and expands and contracts significantly due to temperature, making it difficult to accommodate fine wiring.

[0004] Therefore, to address the issues with organic resin materials, interposers (glass wiring substrates) that use glass as the base material are currently being developed. Glass wiring substrates are less susceptible to moisture absorption, and their coefficient of thermal expansion is similar to that of semiconductor elements, reducing the effects of expansion and contraction due to temperature.

[0005] However, when a wiring board is constructed using a glass plate, the glass plate is subjected to the action of stress and the like from the resin films attached to both sides of the glass plate to form the circuit board. When a glass plate with a resin film attached thereto is cut (cut out) to a predetermined size and shape, it has been reported that the action of the resin film causes the glass plate itself to split into layers within itself (layer separation phenomenon). This layer separation of a glass plate is called seware or the like.

[0006] To address the above-mentioned phenomenon of spine cracking in glass plates, a method has been proposed in which holes are formed through the front and back of the glass plate and filled with resin (see Patent Document 1), and a method has been proposed in which a mixture of resin and inorganic filler is applied to the glass plate (see Patent Document 2).

[0007] The adoption of techniques such as those described in Patent Documents 1 and 2 has been shown to be effective in preventing spine cracking during processing of glass sheets. However, these techniques require additional steps during the manufacturing process, such as drilling holes in the glass sheet, filling with resin, and applying various materials, and are not necessarily simple. Furthermore, further improvements in production efficiency are desired due to the risk of breakage during the manufacturing of glass wiring substrates. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-157982 [Patent Document 2] Japanese Patent Publication No. 2020-182006 Summary of the Invention [Problem to be solved by the invention]

[0009] The inventors have reviewed the manufacturing process and other aspects of glass wiring substrates and made extensive improvements, thereby developing effective measures to prevent the inevitable back cracking that occurs when processing glass plates, and have thus developed a glass wiring substrate and a method for manufacturing a glass wiring substrate.

[0010] The present invention has been made in consideration of the above points, and provides a glass wiring substrate and a method for manufacturing a glass wiring substrate that can eliminate the phenomenon (spine cracking) in which the glass plate itself splits into layers inside due to the action of the resin film when the glass plate to which the resin film is attached is cut to manufacture the glass wiring substrate, thereby eliminating defects during manufacturing and increasing productivity. [Means for solving the problem]

[0011] That is, the glass wiring substrate of the embodiment is characterized by comprising a through-hole portion formed in the thickness direction from the first surface portion to the second surface portion of the glass substrate, a conductive material embedded in the through-hole portion, and a resin film portion attached to each of the first surface portion and the second surface portion of the glass substrate, and comprising a glass cut-out portion consisting of a groove portion of a predetermined width formed on the first surface portion and the second surface portion of the glass substrate, and a recess portion joined to the groove portion and cut out from the side edge portion of the glass substrate in the width direction of the glass substrate.

[0012] Furthermore, in the glass wiring substrate, the grooves may be formed at the same positions on the first surface and the second surface in the thickness direction of the glass substrate.

[0013] Furthermore, in the glass wiring substrate, the glass substrate may be rectangular, and the glass cutout portions may be provided on each of the four sides of the first surface portion and the four sides of the second surface portion of the glass substrate.

[0014] Furthermore, in the glass wiring substrate, the depth of the groove may be 1 / 3 to 1 / 10 of the thickness of the glass substrate.

[0015] Furthermore, the glass wiring substrate may be provided with an embedded resin portion that is embedded in the cut-out portion of the glass.

[0016] In addition, the manufacturing method of the glass wiring substrate of the embodiment is characterized by comprising a through hole forming process for forming a through hole in the thickness direction from the first surface portion to the second surface portion of the glass substrate, a conductive material filling process for filling a conductive material in the through hole, a groove forming process for forming grooves of a predetermined width and a predetermined depth on the first surface portion and the second surface portion of the glass substrate, a bonding process for bonding a resin film portion to each of the first surface portion and the second surface portion of the glass substrate, and a cutting process for cutting the glass substrate in the thickness direction together with the resin film portion directly above the groove portion.

[0017] Furthermore, in the method for manufacturing a glass wiring substrate, the grooves may be formed by cutting or etching in the groove forming step.

[0018] Furthermore, in the method for manufacturing a glass wiring substrate, the grooves may be formed at the same positions on the first surface and the second surface in the thickness direction of the glass substrate.

[0019] Furthermore, in the method for manufacturing a glass wiring substrate, the depth of the groove may be 1 / 3 to 1 / 10 of the thickness of the glass substrate.

[0020] Furthermore, the manufacturing method of the glass wiring substrate may include a resin filling step between the groove forming step and the adhering step, in which a resin member is injected into the groove to form a filled resin portion. [Effects of the Invention]

[0021] The glass wiring substrate of the present invention comprises a through-hole portion formed in the thickness direction from the first surface portion to the second surface portion of the glass substrate, a conductive material filled in the through-hole portion, and a resin film portion attached to each of the first surface portion and the second surface portion of the glass substrate, and a glass cut-out portion consisting of a groove portion of a predetermined width formed on the first surface portion and the second surface portion of the glass substrate, and a recess portion joined to the groove portion and cut out from the side edge portion of the glass substrate in the width direction of the glass substrate.Therefore, it is possible to eliminate the phenomenon (spine cracking) in which the glass plate itself cracks into layers inside itself due to the action of the resin film when a glass plate with a resin film attached is cut to manufacture a glass wiring substrate.

[0022] Furthermore, the method for manufacturing a glass wiring substrate of the present invention includes a through-hole forming step for forming a through-hole in the thickness direction from the first surface to the second surface of the glass substrate, a conductive material filling step for filling a conductive material in the through-hole, a groove forming step for forming grooves of a predetermined width and a predetermined depth on the first surface and the second surface of the glass substrate, a bonding step for bonding a resin film to each of the first surface and the second surface of the glass substrate, and a cutting step for cutting the glass substrate in the thickness direction together with the resin film directly above the groove.Therefore, when a glass plate with a resin film bonded thereto is cut to manufacture a glass wiring substrate, the action of the resin film on the glass plate causes the glass plate itself to crack in layers within itself (spine cracking), which can be eliminated, thereby eliminating manufacturing defects and increasing productivity. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a cross-sectional view of a glass wiring substrate according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic cross-sectional view of only a glass substrate. [Figure 3] 1 is a schematic cross-sectional view of a glass wiring substrate provided with an embedded resin portion; [Figure 4] 1A to 1C are (A) a first cross-sectional view, (B) a second cross-sectional view, and (C) a third cross-sectional view showing a manufacturing process of a glass wiring substrate. [Figure 5] FIG. 10 is a fourth schematic cross-sectional view showing a manufacturing process of the method for manufacturing a glass wiring substrate. [Figure 6] FIG. 5 is a fifth cross-sectional view schematically illustrating a manufacturing process of the method for manufacturing a glass wiring substrate. [Figure 7] FIG. 6 is a sixth cross-sectional view showing a manufacturing process of the manufacturing method for a glass wiring substrate. [Figure 8] 1A to 1C are (A) a first cross-sectional view, (B) a second cross-sectional view, and (C) a third cross-sectional view showing a manufacturing process of a method for manufacturing a glass wiring substrate provided with an embedded resin portion. DETAILED DESCRIPTION OF THE INVENTION

[0024] The glass wiring substrate of the embodiment is a glass substrate having through-holes penetrating the front and back surfaces of the glass substrate, with a conductive metal material disposed in the through-holes, and is primarily used as an interposer. The glass interposer referred to here is a member that serves as a relay substrate for electrically connecting semiconductor elements, such as various memories, CPUs, and GPUs, mounted on a circuit board to the circuit board via wiring. In particular, since the glass interposer itself is formed only from glass and a conductive material for wiring, it does not include materials with different thermal expansion coefficients, such as resin, and thus reduces deformation due to heat exposure during use. Of course, the glass wiring substrate of the embodiment can be used for various applications other than interposers.

[0025] First, the structure of a glass wiring substrate 1 according to an embodiment will be described with reference to the cross-sectional schematic diagrams of FIGS. 1 to 3. The glass wiring substrate 1 includes a glass substrate 10 that constitutes the main structure of the substrate. The glass substrate 10 is made of a material such as alkali-free glass or borosilicate glass. A through-hole 13 is formed in the thickness direction of the glass substrate 10 from the first surface 11 to the second surface 12. Resin film portions 20, 20 are attached to each of the first surface 11 and the second surface 12 of the glass substrate 10. In the illustration, multiple resin film portions 20, 20 (four resin film portions 21, 22, 23, and 24) are attached to each of the first surface 11 and the second surface 12. The resin film portions are made of a material with good stretchability and insulating properties, and a film such as an epoxy resin is used.

[0026] The through-holes 13 are formed in the glass substrate 10 by known methods such as laser light irradiation or etching with an acid or alkaline chemical solution. A conductive material 14 is embedded inside the through-holes 13. The conductive material 14 is a conductive resin paste containing fine particles of metal such as copper, silver, gold, platinum, nickel, or lead. This ensures the conductivity of the through-holes 13 from the first surface 11 to the second surface 12. Alternatively, the inside of the through-holes 13 can be plated with copper or silver to make them conductive.

[0027] The resin film portions 20, 20 (resin film portions 21, 22, 23, 24, respectively) have wiring portions 15 formed thereon, which provide electrical conductivity on both the first surface portion 11 side and the second surface portion 12 side of the glass substrate 10. The structure and position of the wiring portion 15 may be determined appropriately depending on the design of the glass wiring substrate 1, and the illustration is merely a schematic example.

[0028] A structural feature of the glass wiring substrate 1 of the embodiment is that grooves 31 of a predetermined width are formed on the first surface 11 and the second surface 12 of the glass substrate 10. In Fig. 1, grooves 31 are formed in the depth direction of the glass substrate 10. Then, a glass cutout portion 30 is provided, which is joined to grooves 31 and includes a recess 32 cut out from a side edge 10e of the glass substrate 10 in the width direction of the glass substrate 10. Recess 32 is formed in the width direction of the glass substrate 10.

[0029] The groove portions 31 are formed at the same positions on the first surface portion 11 and the second surface portion 12 in the thickness direction of the glass substrate 10. As will be described later in the manufacturing method, the glass substrate 10 is cut together with the resin film portions 20, 20. Therefore, in one cutting operation, the positions of the groove portions 31 need to be aligned in order to separate the glass substrate 10 at the center of the groove portions 31, and the formation positions of the groove portions 31 are aligned on the front and back of the glass substrate 10.

[0030] The glass wiring substrate 1 of the embodiment is square or rectangular to match the shape of the semiconductor element mounted on the circuit board. Therefore, the glass substrate 10 is rectangular (square or rectangular). The glass cutout portions 30 are provided around the periphery of the rectangular glass substrate 10, on each of the four sides of the first surface 11 and the second surface 12. FIG. 2 is a schematic cross-sectional view of only the glass substrate 10. As can be seen from the illustration, the glass cutout portions 30 are provided at each of the four corners on the first surface 11 side and the four corners on the second surface 12 side of the glass substrate 10 (the illustration only partially shows the cross section). The glass cutout portions 30 are shaped like stepped notches. In other words, recessed portions are formed in the shape of elongated rectangular parallelepipeds at each of the four corners on the first surface 11 side and the four corners on the second surface 12 side of the glass substrate 10, where the glass cutout portions 30 have been removed.

[0031] Here, the depth (Tc) of the groove 31 is within the range of 1 / 3 to 1 / 10 of the thickness (Ta) of the glass substrate 10. The preferred thickness of the glass substrate 10 is 0.2 to 1.2 mm. The depth of the groove 31 is determined taking into account the thickness of the glass substrate 10. If the depth of the groove 31 is too deep relative to the glass substrate 10, the thin glass substrate 10 protrudes around the periphery (four corners) of the glass substrate 10, which tends to reduce the structural strength. If the depth of the groove 31 is too shallow relative to the glass substrate 10, it becomes difficult for the groove 31 to function properly and, as explained in the manufacturing method described below, it becomes difficult for the groove 31 to contribute to stress relief when the glass substrate 10 is cut together with the resin film portions 20, 20. For this reason, the depth of the groove 31 described above is a preferred example.

[0032] FIG. 3 is a cross-sectional schematic diagram of an embodiment in which an embedded resin portion 40 is provided in a glass wiring substrate 1. Details are the same as in FIG. 1, so a repeated explanation will be omitted. According to the embodiment of FIG. 3, an embedded resin portion 40 is provided in a glass cutout portion 30 consisting of a groove portion 31 and a depression portion 32. The embedded resin portion 40 is made of various resins such as epoxy resin, thermosetting resin, and UV-curable (ultraviolet-curable) resin. The embedded resin portion 40 is applied to the glass cutout portion 30. The role of the embedded resin portion 40 is to absorb stress generated in the resin film portions 20, 20 on the embedded resin portion 40 side when the glass substrate 10 is cut together with the resin film portions 20, 20, thereby mitigating the propagation of the stress.

[0033] Next, a method for manufacturing a glass wiring substrate according to an embodiment will be described with reference to the schematic diagrams of Figures 4 to 8. In Figure 4(A), a glass substrate 10 constituting a glass wiring substrate 1 according to an embodiment is prepared. In Figure 4(B), through-holes 13 are formed in the glass substrate 10 in the thickness direction from the first surface 11 to the second surface 12 ("through-hole forming step"). The through-holes 13 in the glass substrate 10 are formed by perforation by immersion (etching) in an acidic chemical such as hydrofluoric acid or an alkaline chemical such as caustic soda, or by perforation by laser light irradiation, or a combination of both.

[0034] In FIG. 4(C), after the through-holes 13 are formed, a conductive material is filled into the through-holes 13 (the "conductive material filling step"). The conductive material 14 is a conductive resin paste containing fine particles of metal such as copper, silver, gold, platinum, nickel, or lead. Thus, the conductivity of the through-holes 13 from the first surface 11 to the second surface 12 is ensured by the conductive material 14. Alternatively, copper or silver plating is formed inside the through-holes 13 to make the through-holes 13 conductive.

[0035] In FIG. 5, grooves 31 of a predetermined width and depth are formed on the first surface 11 and the second surface 12 of the glass substrate 10 ("groove forming step"). In this embodiment, when forming the grooves 31 on both surfaces of the glass substrate 10, a cutting wheel 50 (rotary blade) containing diamond powder is brought into contact with the glass substrate 10. The surface of the glass substrate 10 is cut (ground) to form the grooves 31 of a predetermined width and depth. Instead of using the cutting wheel 50, immersion (etching) in an acidic chemical solution such as hydrofluoric acid or an alkaline chemical solution such as caustic soda is employed. In the case of etching, the grooves 31 may be formed simultaneously with the formation of the through-holes 13.

[0036] When forming the grooves 31, the grooves 31 are formed at the same positions on the first surface 11 and the second surface 12 in the thickness direction of the glass substrate 10. This is to align the positions when cutting as described below.

[0037] The depth (Tc) of groove 31 is 1 / 3 to 1 / 10 of the thickness (Ta) of glass substrate 10, as explained in Fig. 1. The depth of groove 31 is adjusted by the amount of cutting of glass substrate 10 by cutting wheel 50 (rotary blade), the thickness of cutting wheel 50 itself, or the etching time, chemical concentration, number of times, etc. The size of depression 32 (see Fig. 1) formed together with groove 31 is also adjusted by the amount of cutting of glass substrate 10 by cutting wheel 50, the thickness of cutting wheel 50 itself, or the etching time, chemical concentration, number of times, etc.

[0038] 6, resin film portions 20 are attached to the first surface 11 and the second surface 12 of the glass substrate 10 ("attaching step"). Similar to the example in FIG. 1, wiring portions 15 are formed on the resin film portions 20, 20 (resin film portions 21, 22, 23, 24, respectively), and electrical conductivity is achieved on both the first surface 11 side and the second surface 12 side of the glass substrate 10.

[0039] 7, the glass substrate 10 is cut in the thickness direction together with the resin film portions 20, 20 (resin film portions 21, 22, 23, 24, respectively) directly above the groove portions 31, 31 on each of the first surface 11 side and the second surface 12 side of the glass substrate 10 ("cutting step"). That is, the glass substrate 10 is cut together with the resin film portions 20, 20 by a cutting wheel 50. After cutting, the cross-sectional shape of the glass cut-off portion 30 in FIG. 1 (groove portion 31 and recess portion 32) appears.

[0040] As can be seen from the figure, grooves 31, 31 are formed on both the first surface 11 side and the second surface 12 side of the glass substrate 10. In other words, the glass substrate 10 around the grooves 31, 31 is not in contact with the resin film portions 20, 20. Therefore, when the cutting wheel 50 (rotary blade) comes into contact with the resin film portions 20, 20, the stress generated in the resin film portions 20, 20 is limited to the resin film portions 20, 20, and therefore transmission of the stress from the resin film portions 20, 20 to the glass substrate 10 is suppressed. Therefore, the effect of excess stress generated from the resin film portions 20, 20 on the glass substrate 10 is mitigated, and deformation of the glass substrate 10 is avoided. As a result, this is an effective measure against the phenomenon (spine cracking) in which the glass plate itself splits into layers internally.

[0041] 8A and 8B show a method for manufacturing a glass wiring substrate according to another embodiment. In the illustrated example, a "resin embedding step" is provided between the groove forming step and the bonding step, in which a resin material is injected into the groove 31 to form an embedded resin portion 40. In FIG. 8A, as shown in FIG. 5 above, grooves 31, 31 are formed on each of the first surface 11 side and the second surface 12 side of the substrate. Then, as shown in FIG. 8B, a resin material is injected into each of the grooves 31, 31 to form an embedded resin portion 40. The embedded resin portion 40 is made of various resins such as epoxy resin, thermosetting resin, and UV-curable (ultraviolet-curable) resin.

[0042] Next, as shown in FIG. 8(C), resin film portions 20, 20 (resin film portions 21, 22, 23, and 24, respectively) are laminated while the embedded resin portion 40 is still present, thereby forming the wiring portion 15. Thereafter, as shown in the figure, the resin film portions 20, 20 are cut at the positions of the grooves 31, 31 using a cutting wheel 50 (rotary blade). The embedded resin portion 40 is made of a material that is more elastic than the glass substrate 10. When the cutting wheel 50 (rotary blade) comes into contact with the resin film portions 20, 20, the stress generated in the resin film portions 20, 20 is limited to the resin film portions 20, 20, and therefore the transmission of the stress from the resin film portions 20, 20 to the glass substrate 10 is suppressed by the embedded resin portion 40. Therefore, the effect of excess stress generated by the resin film portions 20, 20 on the glass substrate 10 is alleviated by the embedded resin portion 40, which prevents deformation of the glass substrate 10. As a result, this is an effective measure against the phenomenon (spine cracking) in which the glass plate itself splits into layers inside. [Explanation of symbols]

[0043] 1 Glass wiring board 10 Glass substrate 10e side edge 11 First side 12 Second side part 13 Through-hole section 14 Conductive Materials 15 Wiring section 20(21,22,23,24) Resin film part 30 Glass cutting section 31 Groove 32 depression 40 Buried resin part 50 Cutting wheel (rotary blade)

Claims

1. a through-hole formed in a thickness direction from the first surface portion to the second surface portion of the glass substrate; A conductive material filled in the through hole; a resin film portion attached to each of the first surface portion and the second surface portion of the glass substrate, grooves of a predetermined width formed on the first surface and the second surface of the glass substrate; a recessed portion joined to the groove portion and cut out from the side edge of the glass substrate in the width direction of the glass substrate; A glass wiring substrate characterized by:

2. The glass wiring substrate according to claim 1 , wherein the grooves are formed at the same positions on the first surface and the second surface in the thickness direction of the glass substrate.

3. The glass substrate is rectangular, The glass wiring substrate according to claim 2 , wherein the glass cutout portions are provided on four sides of the first surface portion and four sides of the second surface portion of the glass substrate.

4. 2. The glass wiring substrate according to claim 1, wherein the depth of the groove is 1 / 3 to 1 / 10 of the thickness of the glass substrate.

5. The glass wiring substrate according to claim 1 , further comprising an embedded resin portion embedded in the cut-out glass portion.

6. a through-hole forming step of forming a through-hole in a thickness direction from the first surface portion to the second surface portion of the glass substrate; a conductive material filling step of filling the through-hole portion with a conductive material; a groove forming step of forming grooves having a predetermined width and a predetermined depth on the first surface and the second surface of the glass substrate; a bonding step of bonding a resin film portion to each of the first surface portion and the second surface portion of the glass substrate; a cutting step of cutting the glass substrate together with the resin film portion directly above the groove portion in a thickness direction. A method for manufacturing a glass wiring substrate, comprising:

7. 7. The method for manufacturing a glass wiring substrate according to claim 6, wherein the grooves are formed by cutting or etching in the groove forming step.

8. The method for manufacturing a glass wiring substrate according to claim 6 , wherein the grooves are formed at the same positions on the first surface and the second surface in the thickness direction of the glass substrate.

9. 7. The method for manufacturing a glass wiring substrate according to claim 6, wherein the depth of the groove is 1 / 3 to 1 / 10 of the thickness of the glass substrate.

10. 7. The glass wiring substrate according to claim 6, further comprising a resin filling step between the groove forming step and the adhering step, for forming a resin filling portion by injecting a resin material into the groove.

Images