Glass wiring substrate and method for manufacturing the same

Abstract

To provide a technique capable of suppressing the occurrence of a glass crack on an end of a conductor layer formed on a glass plate on a glass wiring board.SOLUTION: A glass wiring board comprises: a glass plate; and a conductor layer formed on the glass plate. The conductor layer includes a structure in which a first metal layer, a second metal layer, a third metal layer and a fourth metal layer are sequentially laminated from the glass plate side. In the cross-sectional view, the width of the fourth metal layer is narrower than the width of the first metal layer, the width of the second metal layer and the width of the third metal layer. The etching rate in the acid solution of the fourth metal layer is faster than the etching rate in the acid solution of the third metal layer. The first metal layer is a titanium sputter film, the second metal layer is a copper sputter film, the third metal layer is an electroless nickel plating film and the fourth metal layer is an electrolytic copper plating film.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a glass wiring board and a method for manufacturing the same.

Background Art

[0002] In recent years, the functionality and miniaturization of electronic devices have been advancing. Along with this, higher density of semiconductor modules mounted on electronic devices has been required. In order to meet such requirements, increasing the wiring density of wiring boards for mounting semiconductor chips has been considered.

[0003] As the core material included in the wiring board, glass epoxy resin is generally used (Patent Document 1). In recent years, glass wiring boards using a glass plate as the core material have attracted attention.

[0004] A glass plate can achieve higher smoothness compared to a core material made of glass epoxy resin. Therefore, in a glass wiring board, formation of ultra-fine wiring is possible. Therefore, using a glass wiring board enables high-density mounting.

[0005] Also, the coefficient of thermal expansion (CTE) of a glass plate in the temperature range of 20°C to 260°C is almost the same as that of a semiconductor chip using a silicon substrate in the temperature range of 20°C to 260°C. Therefore, using a glass wiring board enables mounting with small residual stress.

[0006] Furthermore, a glass wiring board has a lower dielectric loss tangent (tanδ) than a silicon interposer and is excellent in high-speed transmission.

[0007] From the above, glass wiring boards have attracted attention as one of the wiring boards for semiconductor modules mounted on high-performance electronic devices.

Prior Art Documents

Patent Documents

[0008] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2000-252630 Summary of the Invention Problems to be Solved by the Invention

[0009] A glass wiring board has a conductor layer formed on a glass plate. As a glass wiring board, a glass wiring board 1 in which a capacitor is formed on a glass plate 10 as shown in FIG. 1 has been proposed.

[0010] The glass wiring board 1 shown in FIG. 1 includes a conductor layer M100 composed of a titanium sputtering layer M101, a copper sputtering layer M102, and an electrolytic copper plating layer M103, a conductor layer M200 composed of a titanium sputtering layer M201, a copper sputtering layer M202, and an electrolytic copper plating layer M203, a dielectric layer DE, a conductor layer M300 composed of a titanium sputtering layer M301, a copper sputtering layer M302, and an electrolytic copper plating layer M303, and a resin layer IL. The conductor layer M100 functions as a wiring or a pad. The conductor layer M200, the dielectric layer DE, and the conductor layer M300 form a capacitor. The conductor layer M200 functions as a lower electrode, and the conductor layer M300 functions as an upper electrode. Note that the purpose of titanium sputtering is to ensure the adhesion between layers, and copper sputtering is used as a seed layer when forming the electrolytic copper plating layer.

[0011] Here, the total thickness t of the conductor layer M100, the conductor layer M200, the dielectric layer DE, and the conductor layer M300 is approximately 30 μm. In this case, due to the difference in the linear expansion coefficients between the dominant copper in the conductor layer M100, the conductor layer M200, the dielectric layer DE, and the conductor layer M300 and the glass plate 10 (copper: 17 ppm / K, glass: 3 ppm / K), cracks may occur in the glass at the end portion P1 of the portion where the conductor layer is in contact with the glass plate as shown in FIG. 1. Cracks occur in the glass at the end portion P1 because the stress of the conductor layer M100, the conductor layer M200, the dielectric layer DE, and the conductor layer M300 acts on the glass plate.

[0012] Therefore, an object of the present invention is to provide a technique capable of suppressing the occurrence of glass cracks at the end of a conductor layer formed on a glass plate in a glass wiring board. **Means for Solving the Problems**

[0013] To solve the above problems, one of the typical glass wiring boards of the present invention includes a glass plate and a conductor layer formed on the glass plate. The conductor layer has a structure in which a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer are sequentially laminated from the glass plate side. In a cross-sectional view, the width of the fourth metal layer is narrower than the widths of the first metal layer, the second metal layer, and the third metal layer. **Effects of the Invention**

[0014] According to the present invention, in a glass wiring board, the occurrence of glass cracks at the end of a conductor layer formed on a glass plate can be suppressed.

[0015] Problems, configurations, and effects other than those described above will be clarified by the description in the following embodiments for carrying out the invention. **Brief Description of the Drawings**

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6A

Figure 6B

Figure 6C

Figure 6D

Figure 6E

Figure 6F

Figure 7

Figure 8

Figure 9

DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited by this embodiment. In the following description, the same reference numerals are used for parts having the same element or the same function, and redundant descriptions are omitted. In the present disclosure, the "width of the metal layer" means the length from one end to the other end of the metal layer in a cross-section perpendicular to the main surface of the glass plate. For example, the width of the first metal layer M11 of the conductor layer M10 that functions as a pad on which the capacitor shown in FIG. 3 is stacked is the length from one end a to the other end b, and the width of the first metal layer M11 of the conductor layer that functions as a pad formed around the through hole TH is the length from one end c to the other end d. The width of the metal layer constituting the conductor layer that functions as a wiring connecting the two pads shown in FIG. 2 is the length in a direction perpendicular to the longitudinal direction.

[0018] FIG. 2 is a plan view schematically showing a part of a glass wiring board according to an embodiment of the present invention. As shown in FIG. 2, the glass wiring board 2 includes a glass plate 10 having a through hole TH, a conductor layer ML1, and a conductor layer ML2. The conductor layer ML1 may form a desired circuit together with a conductor layer or an interlayer via not shown in FIG. 2.

[0019] FIG. 3 is a cross-sectional view taken along line F2-F2 of the glass wiring board 2 shown in FIG. 2. FIG. 3 is a cross-sectional view when the present invention is applied to a conductor layer M10 that functions as a pad on which a capacitor is laminated among the conductor layers ML1 and a portion that functions as a pad formed around the through hole TH among the conductor layers ML2. The conductor layer to which the present invention is applied includes a first metal layer M11 (hereinafter, metal layer M11), a second metal layer M12 (hereinafter, metal layer M12), a third metal layer M13 (hereinafter, metal layer M13), and a fourth metal layer M14 (hereinafter, metal layer M14). The present invention is also applied to a portion that functions as a wiring connecting two pads among the conductor layers ML2 shown in FIG. 2.

[0020] Similar to the conductor layer M200, the dielectric layer DE, and the conductor layer M300 shown in FIG. 1, the conductor layer M20, the dielectric layer DE, and the conductor layer M30 shown in FIG. 3 form a capacitor. The conductor layer M20 includes a metal layer M21, a metal layer M22, and a metal layer M23. The conductor layer M30 includes a metal layer M31, a metal layer M32, and a metal layer M33. The inside of the through hole TH of the glass wiring board 2 is filled with a resin layer IL.

[0021] Also, as shown in FIG. 4, the inside of the through hole TH of the glass wiring board 2 may be filled with a metal layer M14. The glass wiring board 2 may include a catalyst layer not shown in FIGS. 3 and 4.

[0022] The glass plate 10 typically has light transmissibility. The components of the glass material constituting the glass plate 10 and their blending ratios are not particularly limited. As the glass plate 10, for example, glass mainly composed of silicate such as non-alkali glass, alkali glass, borosilicate glass, quartz glass, sapphire glass, photosensitive glass, etc. can be used. From the perspective of being used in semiconductor packages and semiconductor modules, it is desirable to use non-alkali glass. The content rate of the alkali component contained in the non-alkali glass is preferably 0.1 mass% or less.

[0023] Considering the ease of forming the through hole TH and the handling property during manufacturing, the thickness of the glass plate 10 is preferably in the range of 0.1 mm or more and 0.8 mm or less. However, when the formation of the through hole TH is not required, the thickness is not particularly limited.

[0024] Examples of the manufacturing method of the glass plate 10 include the float method, the down-draw method, the fusion method, the up-draw method, the roll-out method, etc. The glass plate 10 may be made by any method.

[0025] The linear expansion coefficient of the glass plate 10 is 0.5×10 -6 / K or more and 15.0×10 -6 / K or less in the temperature range of 20°C to 260°C, preferably 1×10 -6 / K or more and 8.0×10 -6 / K or less, more preferably 1×10 -6 / K or more and 4.0×10 -6 / K or less. When the linear expansion coefficient of the glass plate 10 is within this range, the difference from the linear expansion coefficient of the semiconductor chip using the silicon substrate surface-mounted on the glass wiring substrate 2 tends to be small. Note that the linear expansion coefficient means the ratio at which the length changes corresponding to the rise in temperature.

[0026] At least one main surface of the glass plate 10 may be provided with a functional layer. Examples of the functional layer include an antireflection layer containing fine particles, an infrared shielding layer containing an infrared absorber, a strength-imparting layer containing a hard coat material, an antistatic layer containing an antistatic agent, a colored layer containing a colorant, an optical filter layer containing an optical thin film, a texture control layer containing a light-scattering film, an antiglare layer, and the like. Such a functional layer can be formed by surface treatment techniques such as vapor deposition, sputtering, and wet methods.

[0027] The glass plate 10 may be provided with a through hole TH. The shape of a cross section parallel to the length direction of the through hole may be rectangular, an X shape, that is, a shape in which the diameter at the center is smaller than the top diameter and the bottom diameter of the through hole, a tapered shape, that is, a shape in which the bottom diameter is smaller than the top diameter of the through hole, an O shape, that is, a shape in which the diameter at the center is larger than the top diameter and the bottom diameter of the through hole, or other shapes. The shape of a cross section perpendicular to the length direction of the through hole may be circular, elliptical, or polygonal.

[0028] FIG. 5 is an enlarged view of the conductor layer ML1 shown in FIGS. 3 and 4. As shown in FIG. 5, by making the conductor layer M10 have a stepped shape, the stresses of the conductor layer M20, the conductor layer M30, and the metal layer M14 are dispersed and act on the glass plate 10 and the resin layer IL, and glass cracks at the end portion P2 of the portion where the conductor layer is in contact with the glass plate can be suppressed.

[0029] To form such a shape, the etching rate relationship of the metal layers M11, M12, M13, and M14 in the acidic etchant should be M14 > M12 > M13 >> M11. Due to such differences in etching rates, when etching and removing the metal layer M12 in the manufacturing process, the step shape shown in FIG. 5 according to this embodiment can be obtained. Specifically, this step shape means that the width L-M14 of the metal layer M14 is narrower than the widths L-M11, L-M12, and L-M13 of the metal layer M11, the metal layer M12, and the metal layer M13 (L-M14 < L-M11, L-M12, L-M13).

[0030] For the metal layers M11, M12, M13, and M14, any metal can be selected as long as the etching rate relationship in the acidic etchant is M14 > M12 > M13 >> M11. However, for the metal layer M11, titanium, which ensures adhesion to glass and shows low solubility in the acidic etchant, is desirable. Considering the adhesion between the metal layer M11 made of titanium and the metal layer M13, it is desirable to select copper for the metal layer M12. The metal layers M11 and M12 are preferably formed by sputtering considering ease of manufacturing and manufacturing cost. Also, considering wiring resistance, ease of manufacturing, and manufacturing cost, the metal layer M14, which is the thickest among the metal layers M11, M12, M13, and M14, is preferably copper formed by electroplating.

[0031] For the metal layer M13, nickel, which has the slowest etching rate in the acidic etchant compared to the metal layers M14 and M12, is desirable. Nickel may be formed in a vacuum or may be an electroless nickel plating film. However, when the glass plate 10 is provided with a through hole TH, it is desirable to use an electroless nickel plating film for the metal layer M13.

[0032] When an electroless nickel film is formed, phosphorus derived from a hypophosphite-based compound, which is a reducing agent contained in the electroless nickel plating solution, is eutectic in the film.

[0033] When the metal layer M13 is an electroless nickel plating film, the phosphorus concentration contained in the film is not particularly limited, and for example, it can be selected within the range from 0.1 wt% to 12 wt%.

[0034] When the thickness of the metal layer M13 made of electroless nickel plating is more than 1 μm, the adhesion with the glass inside the through hole TH decreases. Therefore, the film thickness is preferably 1 μm or less, more preferably 0.3 μm or less, and still more preferably 0.1 μm or less. By reducing the film thickness, the time required for forming the electroless nickel plating film can be shortened.

[0035] In addition to phosphorus, which is a eutectic substance derived from the reducing agent, the electroless nickel plating film may also contain sulfur, lead, bismuth, etc. contained in the electroless nickel plating solution. Alternatively, by using a chemical agent containing boron as the reducing agent, boron may be contained in the electroless nickel plating film.

[0036] When the metal layer M13 is an electroless nickel plating film (phosphorus content rate is 5 wt% or less), for the purpose of removing the metal layer M12, when immersed in an acidic etching agent, due to the etching rate relationship of M14 > M12 > M13 >> M11, a stepped shape is formed.

[0037] Also, when the metal layer M13 is an electroless nickel plating film (phosphorus content rate is higher than 5 wt%), for the purpose of removing the metal layer M12, when immersed in an acidic etching agent, due to the etching rate relationship of M14 > M12 >> M13, M11, a stepped shape is formed.

[0038] That is, regardless of the phosphorus content rate in the electroless nickel plating film, a stepped shape can be obtained, and the intended glass crack suppression effect can be obtained.

[0039] When the metal layer M13 is electroless nickel plating and the metal layer M12 is copper, palladium, which is a catalyst applied to the copper surface during the formation of the electroless nickel plating film, is interposed at the interface between the metal layer M13 and the metal layer M12. The treatment amount of palladium on the copper is not limited.

[0040] As the acidic etchant, a mixture of sulfuric acid and hydrogen peroxide solution, or sodium persulfate, etc. can be used.

[0041] For the metal layers M21 and M22, and the metal layers M31 and M32, for example, those formed by sputtering or CVD methods can be applied, such as Cu, Al, Ti, Cr, Mo, W, Ta, Au, Ir, Ru, Pd, Pt, AlSi, AlSiCu, AlCu, NiFe, ITO, IZO, AZO, ZnO, PZT, TiN, Cu3N4, a single Cu alloy or a combination of a plurality thereof. In this embodiment, considering electrical characteristics, ease of manufacturing, and cost, it is preferable to use a titanium sputtered film for the metal layers M21 and M31, and a copper sputtered film for the metal layers M22 and M32. By configuring such a titanium / copper sputtered film, good adhesion can be ensured between each layer of glass and the conductor layer, between conductor layers, and between the dielectric layer and the conductor layer. Note that, for shortening the tact time of the sputtering process, it is desirable that the total film thickness of titanium and copper be 1 μm or less.

[0042] The metal layers M23 and M33 are formed by an electrolytic plating method. Considering manufacturing cost, ease of manufacturing, and wiring resistance, it is preferable to form copper by an electrolytic plating method for the metal layers M23 and M33.

[0043] The dielectric layer DE is formed by a vacuum process such as sputtering or CVD methods, and can be selected from nitrides and oxides of aluminum, titanium, tantalum, chromium, lanthanum, samarium, ytterbium, yttrium, gadolinium, zirconium, niobium, hafnium, gallium, cerium, silicon, etc. It is desirable to use silicon nitride or aluminum oxide with a low dielectric constant and excellent insulation for the dielectric layer DE.

[0044] The step shape can achieve the effects according to the present invention even when the relationship between the width L-M14 of the metal layer M14, the width L-M11 of the metal layer M11, the width L-M12 of the metal layer M12, and the width L-M13 of the metal layer M13 is L-M14 < L-M13 < L-M12 < L-M11, or even when L-M14 < L-M13 and L-M12 < L-M11.

[0045] Next, a method for manufacturing the conductor layer M10 on the glass plate 10 provided with the through hole TH will be described with reference to FIGS. 6A to 6F.

[0046] As shown in FIG. 6A, the metal layer M11 and the metal layer M12 are formed on both surfaces of the glass plate 10 by sputtering. Specifically, a titanium sputter film is formed as the metal layer M11, and a copper sputter film is formed as the metal layer M12. Further, a catalyst layer CA is formed on the metal layer M12 and inside the TH of the glass plate 10.

[0047] Next, as shown in FIG. 6B, a resist layer RE is formed on the catalyst layer CA, and an opening REO is formed in the resist layer RE. If the catalyst layer CA is not formed before the formation of the resist layer RE and the catalyst layer CA is formed after the formation of the resist layer RE, the catalyst is also adsorbed on the resist layer RE. In this case, an electroless nickel plating film formed in the next step is also deposited on the resist layer RE, and the desired structure cannot be obtained, which is not desirable.

[0048] Next, as shown in FIG. 6C, the metal layer M13 is formed in the opening REO of the resist layer RE. The metal layer M13 is an electroless nickel plating film. Electroless nickel plating is formed by immersing in a solution containing hypophosphorous acid. At this time, phosphorus is eutectic as an impurity in the electroless nickel plating film.

[0049] When forming the metal layer M13 by electroless plating, the metal layer M13 can be selectively formed on the portion where the catalyst layer CA is exposed. However, when the glass substrate 10 does not have the through hole TH, the metal layer M13 is not limited to an electroless nickel plating film, nor is it limited to nickel. That is, if the etching rate in an acidic solution is M14 > M12 > M13 >> M11, the metal species is not limited.

[0050] Next, as shown in FIG. 6D, a metal layer M14 is formed on the metal layer M13 by electrolytic plating. Specifically, an electrolytic copper plating film is formed as the metal layer M14.

[0051] Next, as shown in FIG. 6E, the resist layer RE is peeled off, and the catalyst layer CA and the metal layer M12 are removed. The catalyst layer CA and the metal layer M12 are removed in an acidic solution. In a method of forming the metal layer M13 before forming the resist layer RE without forming the metal layer M13 after forming the resist layer RE, when the metal layer M13 is an electroless nickel plating film with a high phosphorus content, to remove the metal layer M13, it is necessary to immerse it in a high-temperature and high-concentration alkaline solution. At this time, there is a concern that the glass substrate 10 may be embrittled. However, in the method of this embodiment, etching of the electroless nickel plating film itself is unnecessary. That is, since the catalyst layer CA and the metal layer M12 made of copper may be etched in an acidic solution, embrittlement of the glass substrate 10 can be suppressed.

[0052] As the acidic solution, for example, an etching agent containing sulfuric acid or hydrogen peroxide, or a solution containing sodium persulfate or the like can be used. When the phosphorus content contained in the electroless nickel plating film of the metal layer M13 is high, the metal layer M13 is not etched. Therefore, when etching the catalyst layer CA and the metal layer M12, a part of the metal layer M14 is etched, so that the cross section of the conductor layer M10 has a stepped shape.

[0053] On the one hand, when the phosphorus content in the electroless nickel plating film of the metal layer M13 is low, when removing the catalyst layer CA and the metal layer M12, the metal layer M13 and the metal layer M14 are also etched, but due to the difference in etching rate, the width of the metal layer M14 becomes narrower than the width of the metal layer M12 and the width of the metal layer M13. That is, similar to the case where the phosphorus content is high, the cross-section of the conductor layer M10 has a stepped shape.

[0054] Next, as shown in FIG. 6F, by immersing the metal layer M11 made of titanium in a weak alkaline solution, it can be etched and removed, and the glass wiring substrate 2 can be obtained. At this time, in order to maintain the stepped shape, the metal layer M12, the metal layer M13, and the metal layer M14 need to be hardly etched by the alkaline etchant. Since the titanium etchant is weakly alkaline, the glass is not embrittled.

[0055] As the weakly alkaline etchant, a mixture of hydrogen peroxide water and phosphate can be used.

[0056] As described above, by using the manufacturing method of this embodiment, the conductor layer can be formed into a stepped shape, thereby suppressing the occurrence of glass cracks at the portion where the conductor layer and the glass plate are in contact due to the difference in linear expansion coefficient.

Example

[0057] Next, the operational effects when using the configuration and manufacturing method of the glass wiring substrate 2 as described above will be described with reference to FIG. 7 showing examples and FIG. 8 showing comparative examples.

[0058] <Examples 1 to 4> Examples 1 to 4 will be described with reference to FIG. 7. FIG. 7 is a cross-sectional view showing a part of the glass wiring substrate according to the example. The layer configuration is shown in FIG. 9. The layer configurations in Examples 1 to 4 differ only in the phosphorus content of the electroless nickel plating film (metal layer M13) and the thickness of the electrolytic copper plating film (metal layer M14). That is, the phosphorus content of the electroless nickel plating film (metal layer M13) is 1 wt% in Examples 1 and 2, and 7 wt% in Examples 3 and 4, and the thickness of the electrolytic copper plating film (metal layer M14) is 10 μm in Examples 1 and 3, and 15 μm in Examples 2 and 4.

[0059] The pattern size of the conductor layer M10 was 500 μm□, the pattern sizes of the conductor layer M20 and the dielectric layer DE were 300 μm□, and the pattern size of the conductor layer M30 was 250 μm□. For the glass plate 10, a low-expansion type glass with a thickness of 0.5 mm was used. As the acidic etching agent, a mixture of sulfuric acid and hydrogen peroxide water was used, and as the weak alkaline etching agent, a mixture of hydrogen peroxide water and phosphate was used.

[0060] The width L-M14 of the metal layer M14 is narrower than the widths L-M11, L-M12, and L-M13 of the metal layers M11, M12, and M13, forming a stepped shape.

[0061] <Comparative Example 1> Comparative Example 1 will be described with reference to FIG. 8. FIG. 8 is a cross-sectional view showing a part of the glass wiring substrate according to the comparative example. The layer configuration is shown in FIG. 9. The layer configurations in Example 1, Example 3, and Comparative Example 1 differ only in the presence or absence of the electroless nickel plating film (metal layer M13). That is, the electroless nickel plating film (metal layer M13) is present in Examples 1 and 3, and absent in Comparative Example 1.

[0062] The pattern size of the conductor layer M10 was 500 μm□, the pattern sizes of the conductor layer M20 and the dielectric layer DE were 300 μm□, and the pattern size of the conductor layer M30 was 250 μm□. For the glass plate 10, a low-expansion type glass with a thickness of 0.5 mm was used. As the acidic etching agent, a mixture of sulfuric acid and hydrogen peroxide water was used, and as the weakly alkaline etching agent, a mixture of hydrogen peroxide water and phosphate was used.

[0063] The width L-M14 of the metal layer M14 is not narrower than the widths L-M11, L-M12, and L-M13 of the metal layers M11, M12, and M13, and does not form a stepped shape.

[0064] <Confirmation of the effects> As a confirmation of the effects of this embodiment, the following evaluations were performed on the glass wiring boards fabricated in Examples 1 to 4 and Comparative Example 1.

[0065] <Evaluation methods and conditions> The glass wiring boards according to Examples 1 to 4 and Comparative Example 1 having the specifications described in FIG. 9 were evaluated for glass crack resistance by a temperature cycle test (TCT). Test conditions: -55°C / 15 minutes ⇔ 125°C / 15 minutes, 1000 cycles

[0066] <Evaluation results> In Examples 1 to 4 in which the conductor layer M10 exhibited a stepped shape, no glass crack occurred at the end portion P2 shown in FIG. 7, but in the conductor layer M10 without a stepped shape in Comparative Example 1, a crack occurred at the end portion P2 shown in FIG. 8. Thereby, the stress relaxation effect of the conductor layer on the glass plate by forming the conductor layer M10 into a stepped shape was confirmed. Further, in Examples 1 to 4, no crack occurred in the glass regardless of the phosphorus content of the electroless nickel plating film (metal layer M13) and the thickness of the electrolytic copper plating film (metal layer M14).

[0067] The above-described embodiment is an example, and of course, other specific detailed structures and the like can be appropriately changed.

[0068] In addition, although the embodiments in which the present invention is applied to a conductor layer functioning as a pad on which capacitors are stacked and a conductor layer functioning as a pad formed around a through hole have been described, the present invention is generally applicable to a glass wiring substrate including a glass plate and a conductor layer formed on the glass plate.

[0069] The present invention can also be used for a main substrate and a wiring substrate functioning as an interposer interposed between the main substrate and an IC chip.

Explanation of Reference Numerals

[0070] CA catalyst layer TH through hole DE dielectric layer IL resin layer RE resist layer REO opening of resist layer RE 1, 2 glass wiring substrate 10 glass plate M11, M12, M13, M14, M21, M22, M23, M31, M32, M33 metal layer ML1, ML2 conductor layer M10, M20, M30 conductor layer M100, M200, M300 conductor layer M101, M201, M301 titanium sputter layer M102, M202, M302 copper sputter layer M103, M203, M303 electrolytic copper plating layer L-M11 width of the first metal layer M11 L-M12 width of the second metal layer M12 L-M13 width of the third metal layer M13 L-M14 width of the fourth metal layer M14

Claims

1. A glass substrate, a conductor layer formed on the glass substrate, and a glass wiring substrate comprising: the conductor layer has, a structure in which a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer are sequentially laminated from the glass substrate side, in a cross-sectional view, the width of the fourth metal layer laminated directly above the third metal layer is narrower than the width of the first metal layer, the width of the second metal layer, and the width of the third metal layer, and the etching rate of the fourth metal layer in an acidic solution is faster than the etching rate of the third metal layer in the acidic solution. A glass wiring substrate.

2. The glass wiring substrate according to claim 1, wherein the first metal layer is a titanium sputter film, the second metal layer is a copper sputter film, the third metal layer is an electroless nickel plating film, and the fourth metal layer is an electrolytic copper plating film. A glass wiring substrate.

3. The glass wiring substrate according to claim 1 or claim 2, wherein the glass substrate has a through hole, and the third metal layer and the fourth metal layer are sequentially formed on the side wall of the through hole from the glass substrate side. A glass wiring substrate.

4. A glass substrate, a conductor layer formed on the glass substrate, having a structure in which a first metal layer, a second metal layer, a third metal layer, and a fourth metal layer are sequentially laminated from the glass substrate side, and the etching rate of the fourth metal layer in an acidic solution is faster than the etching rate of the third metal layer in the acidic solution, and a method for manufacturing a glass wiring substrate comprising: a step of providing the first metal layer on the glass substrate; a step of providing the second metal layer on the first metal layer; a step of providing a catalyst layer on the second metal layer; a step of providing a resist on the catalyst layer; a step of providing an opening in the resist; a step of providing the third metal layer in the opening of the resist; a step of providing the fourth metal layer on the third metal layer; a step of removing the resist; a step of removing the catalyst layer and the second metal layer; and a step of removing the first metal layer. A method for manufacturing a glass wiring substrate.

5. The method for manufacturing a glass wiring substrate according to claim 4, wherein the glass substrate has a through hole, and the step of providing a catalyst layer on the second metal layer is a step of providing a catalyst layer on the second metal layer and on the side wall of the through hole. A method for manufacturing a glass wiring substrate.

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