Wiring board and method for manufacturing a wiring board

Abstract

Improved adhesion between the glass substrate and the wiring pattern. [Solution] The wiring board 1 of the embodiment includes a glass substrate 10 having a through hole 4 that penetrates between a first surface 10F and a second surface 10S, a conductor 41 that fills the through hole 4, a wiring pattern 211 exposed on the first surface 10F, and an insulating layer 31 laminated on the first surface 10F and covering the wiring pattern 211. The glass substrate 10 has a recessed pattern 10g that extends linearly on the first surface 10F, and the recessed pattern 10g is filled with the wiring pattern 211.

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a wiring board. The disclosed wiring board has a glass substrate and a core substrate including through-hole conductors penetrating the substrate. A build-up layer is formed on both surfaces of the core substrate by alternately laminating resin insulating layers and conductor layers.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the structure of the wiring board shown in Patent Document 1, since the conductor layer is formed only within the build-up layer, it may not be possible to realize a desired electric circuit within a predetermined thickness range. When a conductor layer is provided on the surface of the core substrate mainly composed of a glass substrate in order to add a conductor layer, due to the inherent compatibility regarding the bonding between the glass material and the metal material, the adhesion strength between the glass substrate and the conductor layer may be insufficient, and there may be a concern about the peeling of the conductor layer.

Means for Solving the Problems

[0005] 1] The wiring board of the present invention includes a glass substrate having a first surface and a second surface opposite to the first surface, and a through hole penetrating between the first surface and the second surface; a conductor filling the through hole; a wiring pattern exposed on the first surface; and an insulating layer laminated on the first surface and covering the wiring pattern. The glass substrate has a linear recess pattern extending on the first surface, and the recess pattern is filled with the wiring pattern.

[0006] The present invention relates to a method for manufacturing a wiring board, which includes preparing a glass substrate having a first surface and a second surface opposite to the first surface, forming a wiring pattern so as to be exposed on the first surface of the glass substrate, and forming an insulating layer on the first surface to cover the wiring pattern. The formation of the wiring pattern includes filling linear recessed patterns provided on the first surface with a conductor.

[0007] According to embodiments of the present invention, peeling of the conductive layer from the glass substrate is suppressed, and thus the quality of the wiring board is expected to improve. [Brief explanation of the drawing]

[0008] [Figure 1] A cross-sectional view showing an example of a wiring board according to an embodiment of the present invention. [Figure 2] Enlarged view of section II of the wiring board in Figure 1. [Figure 3] A plan view showing an example of the first surface of a glass substrate in a wiring board of an embodiment. [Figure 4A] A schematic diagram showing a first modified example of a conductive material and wiring pattern filling through holes in a wiring board of an embodiment. [Figure 4B] A schematic diagram showing a second modified example of a conductive material filling through holes and a wiring pattern in a wiring board according to the embodiment. [Figure 4C] A schematic diagram showing a third modified example of a conductive material filling through holes and a wiring pattern in a wiring board of an embodiment. [Figure 5A] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5B] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5C] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5D] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5E] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5F] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 5G] A cross-sectional view showing an example of a process in an example of a manufacturing method for a wiring board according to an embodiment. [Figure 6A] A cross-sectional view showing an example of the steps of a first modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 6B] A cross-sectional view showing an example of the steps of a first modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 6C] A cross-sectional view showing an example of the steps of a first modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 6D] A cross-sectional view showing an example of the steps of a first modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 7A] A cross-sectional view showing an example of a step in a second modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 7B] A cross-sectional view showing an example of a step in a second modified example of the method for manufacturing a wiring board according to the embodiment. [Figure 7C] A cross-sectional view showing an example of a step in a second modified example of the method for manufacturing a wiring board according to the embodiment. [Modes for carrying out the invention]

[0009] <Structure of the wiring board in the embodiment> The wiring board of the embodiment will be described while referring to the drawings. FIG. 1 shows a cross-sectional view of a wiring board 1 which is an example of the wiring board of the embodiment, and FIG. 2 shows an enlarged view of part II in FIG. 1. Note that the wiring boards illustrated in each of the following drawings are merely examples of the wiring board of the embodiment. The laminated structure of the wiring board of the embodiment is not limited to the laminated structure of the wiring boards shown in each drawing, and the number of conductor layers and insulating layers included in the wiring board of the embodiment is not limited to the number of conductor layers and insulating layers included in the wiring boards shown in each drawing. The wiring board of the embodiment may include any number of insulating layers and conductor layers in addition to the insulating layers and conductor layers that the wiring boards shown in each drawing have, and may not include all of the insulating layers and conductor layers that the wiring boards shown in each drawing have. Also, in each of the drawings referred to in the following description, specific portions may be enlarged to facilitate understanding of the disclosed embodiment. Therefore, the components of the wiring board of the embodiment may not be drawn in exact proportions to each other with respect to size and length.

[0010] As shown in FIG. 1, the wiring board 1 includes a glass substrate 10 having a first surface 10F and a second surface 10S which is the opposite surface of the first surface 10F, wiring patterns 211 and 212 exposed on the first surface 10F, and an insulating layer 31 laminated on the first surface 10F and covering the wiring patterns 211 and 212. The glass substrate 10 further includes a through hole 4 penetrating between the first surface 10F and the second surface 10S, and a conductor 41 filling the through hole 4. Also, the wiring board 1 in the example of FIG. 1 includes conductor pads 21p and 22p. The conductor pad 21p is provided between the conductor 41 and the insulating layer 31, and the conductor pad 22p is provided between the conductor 4 and the insulating layer 33.

[0011] In the description of the wiring board of the embodiment, the side far from the glass substrate 10 is also referred to as "upper", "upper side", "above", "outer side", or "outside", and the side close to the glass substrate 10 is also referred to as "lower", "lower side", "below", "inner side", or "inside". Also, in each element constituting the wiring board of the embodiment, the surface facing away from the glass substrate 10 is also referred to as the "upper surface", and the surface facing the glass substrate 10 side is also referred to as the "lower surface".

[0012] A conductor layer 21 is formed on the first surface 10F of the glass substrate 10, and a conductor layer 22 is formed on the second surface 10S. The wiring patterns 211 and 212 are included in the conductor layer 21. The glass substrate 10, together with the conductor layer 21 and the conductor layer 22, constitutes the core substrate 1C of the wiring board 1. A first build-up portion 1F is laminated on the first surface 10F of the glass substrate 10, and a second build-up portion 1S is laminated on the second surface 10S. The first build-up portion 1F is composed of an insulating layer 31 laminated on the first surface 10F and three conductor layers 23 and two insulating layers 32 alternately formed on the insulating layer 31. The second build-up portion 1S is composed of three sets of insulating layers 33 and conductor layers 24 alternately formed on the first surface 10F. In the insulating layers 31 to 33, via conductors 3a are formed to connect conductors formed on both sides in the thickness direction of each insulating layer.

[0013] The conductor layers 21 to 24 may each include an arbitrary conductor pattern. For example, as described above, the conductor layer 21 includes the wiring patterns 211 and 212. In the example of FIG. 1, the conductor layer 21 further includes a conductor pad 21p. The conductor layer 22 includes a conductor pad 22p and further includes wiring patterns 221 and 222. Also, the outermost conductor layer 23 in the first build-up portion 1F includes a conductor pad 23p, and the outermost conductor layer 24 in the second build-up portion 1S includes a conductor pad 24p. The conductor pads 23p and 24p may be used for connection to an external electronic component, mechanical component, such as a semiconductor integrated circuit device, or an arbitrary external substrate such as a motherboard.

[0014] A solder resist layer SR1 is formed on the first build-up section 1F. A solder resist layer SR2 is formed on the second build-up section 1S. The solder resist layer SR1 has an opening to expose the conductor pad 23p, and the solder resist layer SR2 has an opening to expose the conductor pad 24p. The solder resist layers SR1 and SR2 are formed using, for example, a photosensitive epoxy resin or polyimide resin.

[0015] In the wiring board 1, the conductor 41 filling the through-hole 4 in the glass substrate 10 connects the conductor layer 21 and the conductor layer 22. That is, the conductor 41 constitutes a through-hole conductor that connects the conductor layers arranged on both sides of the core substrate 1C. The conductor 41 will also be referred to as the "through-hole conductor 41" below. The conductor pad 21p of the conductor layer 21 and the conductor pad 22p of the conductor layer 22 are connected by the through-hole conductor 41. The conductor pads 21p and 22p function as through-hole pads for the through-hole conductor 41.

[0016] The glass substrate 10 is formed of a glass selected from, for example, soda-lime glass, aluminosilicate glass, borosilicate glass, fluoroglass, chalcogen glass, alkali-free glass, and quartz glass. The glass substrate 10 may also contain additives such as magnesium, calcium, manganese, aluminum, lead, iron, chromium, potassium, sulfur, antimony, and boron.

[0017] The insulating layers 31 to 33 are each formed using an insulating resin such as epoxy resin, bismaleimide triazine resin (BT resin), phenolic resin, or polyimide resin. The insulating layers 31 to 33 may also contain reinforcing materials (core materials) such as glass fibers and / or inorganic fillers such as silica and alumina.

[0018] The conductor layers 21-24, via conductor 3a, and through-hole conductor 41 may be formed from any metal having suitable conductivity. Examples of materials for forming these conductors include copper, nickel, palladium, titanium, tungsten, gold, and silver. For example, the conductor layers 21-24, via conductor 3a, and through-hole conductor 41 may be formed from a metal film created by plating or sputtering.

[0019] Furthermore, although the conductor layers 21-24, via conductors 3a, and through-hole conductors 41 are shown as a simplified single-layer structure in Figure 1 for clarity, they may have a multilayer structure, as shown in the enlarged view of conductor layer 21 in Figure 2. In Figure 2, the wiring pattern 211, i.e., conductor layer 21 and through-hole conductor 41, has a two-layer structure composed of a first metal film 20a (e.g., a copper sputtering film) and a second metal film 20b (e.g., a copper electroplating film). Each conductor layer other than conductor layer 21, and via conductor 3a, may also have a multilayer structure similar to conductor layer 21 illustrated in Figure 2.

[0020] <Wiring pattern structure> Figure 3 shows a plan view of an example of the first surface 10F of the glass substrate 10 in the wiring board 1 of Figure 1. Figure 1 may be a cross-sectional view along line II shown in Figure 3. The wiring patterns 211 and 212 of the wiring board 1 will be further described with reference to Figure 3 in addition to Figures 1 and 2. As shown in Figures 1 to 3, the glass substrate 10 included in the wiring board of the embodiment further has a recess pattern 10g on the first surface 10F. The recess pattern 10g is a groove that extends linearly on the surface of the glass substrate 10 and has a predetermined path in plan view. The recess pattern 10g may also be a groove-like depression or recess. In the wiring board of the embodiment, the recess pattern 10g is filled with the wiring pattern 211.

[0021] In other words, in the wiring substrate of this embodiment, at least a portion of the wiring pattern, such as the wiring pattern 211, that is formed on the surface of the glass substrate is embedded in grooves formed on the surface of the glass substrate. That is, the wiring pattern is in contact not only with the surface of the glass substrate but also with the inner wall surface of the glass substrate that is exposed to the grooves formed on the surface of the glass substrate. Therefore, compared to the wiring pattern of the conventional technology which is formed only on the surface of the glass substrate, the contact area between the wiring pattern and the glass substrate is increased in the wiring substrate of this embodiment. As a result, the adhesion strength between the wiring pattern and the glass substrate is greater than that between the wiring pattern and the glass substrate of the conventional technology. Therefore, peeling of the wiring pattern from the glass substrate, that is, peeling of the conductive layer in contact with the glass substrate from the glass substrate is suppressed.

[0022] In the wiring board 1 illustrated in Figure 1, recessed patterns 10g are also formed on the second surface 10S of the glass substrate 10. These recessed patterns 10g on the second surface 10S are filled with wiring patterns 221 and 222. Consequently, the adhesion strength between the wiring patterns 221 and 222 and the glass substrate 10 is increased compared to conventional wiring patterns. Therefore, delamination between the wiring patterns 221 and 222 and the glass substrate 10, i.e., delamination between the conductor layer 22 and the glass substrate 10, is suppressed.

[0023] In this embodiment, the wiring pattern 211 fills a recessed pattern in part. Therefore, the wiring pattern 211 includes a first portion 21a that fills the recessed pattern 10g and a second portion 21b that protrudes from the first surface 10F of the glass substrate 10. In the example in Figure 2, the first portion 21a of the wiring pattern 211 is composed of a first metal film 20a that is in contact with the inner wall surface of the glass substrate 10 exposed to the recessed pattern 10g and the bottom surface of the recessed pattern 10g, and a second metal film 20b that is surrounded by the first metal film 20a and fills the inner portion of the recessed pattern 10g. On the other hand, the second portion 21b of the wiring pattern 211 is composed almost entirely of the second metal film 20b and does not include the first metal film 20a. The first metal film 20a may be, for example, a sputtering film or an electroless plating film. Furthermore, the second metal film 20b may be, for example, an electroplated film formed by electroplating using the first metal film 20a as a power supply layer.

[0024] In the example shown in Figure 2, the width Wa of the first portion 21a and the width Wb of the second portion 21b of the wiring pattern 211 are approximately the same. The widths Wa of the first portion 21a and Wb of the second portion 21b of the wiring pattern 211 may be, for example, 0.5 μm or more and 20 μm or less. When a wiring pattern 211 that has high adhesion to the glass substrate 10 has widths Wa and Wb within this range, complex circuits can be realized in a small occupied area by high-density wiring with little peeling from the glass substrate.

[0025] The thickness Ta of the first portion 21a and the thickness Tb of the second portion 21b of the wiring pattern 211 may be approximately the same, as shown in the example in Figure 2. Furthermore, the thickness Tp of the conductor pad 21p may be approximately the same as the thickness Tb of the second portion 21b of the wiring pattern 211. The thickness Ta of the first portion 21a, the thickness Tb of the second portion 21b, and the thickness Tp of the conductor pad 21p may be, for example, 0.5 μm or more and 20 μm or less.

[0026] In the wiring board of this embodiment, the "wiring pattern" is a conductor pattern that extends between predetermined pads and connects them to each other, as shown in the wiring patterns 211 and 212 in Figure 3. Furthermore, in terms of function, the "wiring pattern" is a conductor pattern that transmits signals, supplies voltage or power, or through which current flows. Therefore, the "wiring pattern" is distinguished from conductor pads used for connecting to external components or other boards, or to via conductors or through-hole conductors, or so-called solid patterns. The width of the wiring pattern, such as width Wa and width Wb, is the length of the wiring pattern in a direction substantially perpendicular to the direction in which the wiring pattern extends. The wiring board of this embodiment may include, on the surface of the glass substrate, wiring patterns that are not embedded in the glass substrate, in addition to wiring patterns that are partially embedded in the glass substrate, such as wiring pattern 211.

[0027] In the wiring board of the embodiment, the wiring pattern partially embedded in the glass substrate may connect a conductor pad 21p that functions as a through-hole pad to other conductor pads 21pp, as shown in the wiring pattern 211 in Figure 3. In the example in Figure 3, the conductor pad 21pp may be a so-called via conductor receiving pad. That is, the conductor pad 21pp may be a conductor pad that connects to a via conductor that connects to a conductor layer above the wiring pattern partially embedded in the glass substrate. Furthermore, the wiring pattern partially embedded in the glass substrate may connect conductor pads 21p that function as through-hole pads to each other, or conductor pads 21pp that are via conductor receiving pads to each other. In addition, the wiring pattern partially embedded in the glass substrate may connect other conductor pads via a conductor receiving pad 21pp, as shown in the wiring pattern 212 in Figure 3, or it may connect other conductor pads via a conductor pad 21p that functions as a through-hole conductor.

[0028] <Variation> Figures 4A to 4C schematically show the first to third modified versions of the conductor 41 filling the through-hole 4 and the wiring pattern 211 filling the recessed pattern 10g. The modified versions shown in Figures 4A to 4C are described below. In Figures 4A to 4C, components similar to those shown in Figure 2 are either denoted by the same reference numerals as in Figure 2 or omitted as appropriate, and repetitive explanations of those components are omitted.

[0029] In the first modified example shown in Figure 4A, the width Wa of the first portion 21a and the width Wb of the second portion 21b of the wiring pattern 211 are different. The width Wb of the second portion 21b is greater than the width Wa of the first portion 21a. Therefore, the second portion 21b is composed of a first metal film 20a that covers the area around the recessed pattern 10g on the first surface 10F of the glass substrate 10, and a second metal film 20b formed on the first metal film 20a. It is believed that the adhesion strength between the wiring pattern 211 and the glass substrate 10 is further improved. Although not shown, in the wiring substrate of the embodiment, in a wiring pattern that is partially embedded in the glass substrate, the width of the portion that protrudes from the surface of the glass substrate (for example, the width Wb in Figure 4A) may be smaller than the width of the portion that is embedded in the glass substrate (for example, the width Wa in Figure 4A).

[0030] Furthermore, in the example in Figure 4A, the thickness Ta of the first portion 21a of the wiring pattern 211 and the thickness Tb of the second portion 21b are different. In the example in Figure 4A, the thickness Tb of the second portion 21b is smaller than the thickness Ta of the first portion 21a. The thickness Tp of the conductor pad 21p is also smaller than the thickness Ta of the first portion 21a. Therefore, a thinner wiring board may be obtained. Note that, unlike the example in Figure 4A, the thickness Tb of the second portion 21b may be larger than the thickness Ta of the first portion 21a.

[0031] In the second modified example shown in Figure 4B, the conductor pad 21p in contact with the conductor (through-hole conductor) 41 in the conductor layer 21 includes a first metal film 20a in contact with the first surface 10F of the glass substrate 10 and the conductor 41, and a second metal film 20b formed on the first metal film 20a. The first metal film 20a included in the conductor pad 21p is formed on the first surface 10F of the glass substrate 10 and the conductor 41 substantially parallel to the first surface 10F. The first metal film 20a may be, for example, a sputtering film or an electroless plating film. The second metal film 20b may be, for example, an electroplating film, and may be formed by electroplating using the first metal film 20a as a power supply layer.

[0032] On the other hand, the conductor 41 filling the through-hole 4 includes a third metal film 20c that is in contact with the inner wall surface of the glass substrate 10 exposed to the through-hole 4, and a fourth metal film 20d that is in contact with the third metal film 20c and fills the portion of the through-hole 4 inside the third metal film 20c. The third metal film 20c may be, for example, a sputtering film or an electroless plating film, similar to the first metal film 20a. The fourth metal film 20d may be, for example, an electroplated film, similar to the second metal film 20b, and may be formed by electroplating using the third metal film 20c as a power supply layer.

[0033] The materials of the third metal film 20c and the fourth metal film 20d may be the same as or different from the materials of the first metal film 20a and the second metal film 20b. That is, since the conductive pad 21p has a structure in which the first metal film 20a, which is formed separately from the third metal film 20c, is provided between the conductive material 41 that fills the through hole 4, different materials can be used for the first metal film 20a and the third metal film 20c. For example, the third metal film 20c may be formed of a material that can have high adhesion to the inner wall surface of the glass substrate 10 exposed in the through hole 4, and the first metal film 20a may be formed of a material suitable for patterning the conductive layer 21.

[0034] In the example shown in Figure 4B, in the thickness direction of the glass substrate 10 (direction Z indicated by arrow Z in Figure 4B), the distance between the surface 4a of the conductor (through-hole conductor) 41 on the first surface 10F side of the glass substrate 10 and the first surface 10F is smaller than the distance between the surface 21c of the wiring pattern 211 and the first surface 10F (i.e., thickness Tb). Surface 21c is the surface of the wiring pattern 211 on the opposite side of the glass substrate 10 from the second surface 10S side (see Figure 1). In particular, in Figure 4B, the distance between the surface 4a of the conductor 41 and the first surface 10F is approximately zero. That is, the surface 4a of the through-hole conductor 41 is exposed to the first surface 10F and is approximately flush with the first surface 10F.

[0035] In the third modified example shown in Figure 4C, the wiring pattern 211 is composed of a first metal film 20a that is in contact with the inner wall surface of the glass substrate 10 exposed in the recess pattern 10g, and a second metal film 20b surrounded by the first metal film 20a. In the example in Figure 4C, the first metal film 20a extends further upward from the first surface 10F of the glass substrate 10. That is, in the example in Figure 4C, a part of the first metal film 20a protrudes from the first surface 10F. The part of the first metal film 20a that protrudes from the first surface 10F constitutes the side surface of the second part 21b of the wiring pattern 211. That is, in the second part 21b as well, the side surface of the second metal film 20b is covered by a part of the first metal film 20a.

[0036] Furthermore, in the example in Figure 4C, the conductor 41 filling the through-hole 4 is composed of a third metal film 20c formed separately from the first metal film 20a constituting the conductor pad 21p, and a fourth metal film 20d surrounded by the third metal film 20c, similar to the conductor 41 in the example in Figure 4B. In the example in Figure 4C, the first metal film 20a constituting the conductor pad 21p extends upward from the first surface 10F in its outer peripheral portion and constitutes the side surface of the conductor pad 21p. That is, in the conductor pad 21p, a part of the first metal film 20a covers the side surface of the second metal film 20b. In the third modified example in which the wiring pattern 211 and the conductor pad 21p have the structure shown in Figure 4C, etching is not used in the formation of the conductor layer 21, as will be described later, so there may be multiple wiring patterns 211 arranged at a fine pitch.

[0037] <Method for manufacturing a wiring board according to an embodiment> Next, with reference to Figures 5A to 5G, an example of a manufacturing method for the wiring board of the embodiment will be described, using the case where the wiring board 1 illustrated in Figure 1 is manufactured as an example. Unless otherwise stated, any of the materials previously described for each component of the wiring board 1 can be used to form each component.

[0038] As shown in Figure 5A, the method for manufacturing a wiring board of the embodiment includes preparing a glass substrate 10 having a first surface 10F and a second surface 10S opposite to the first surface 10F. As the glass substrate 10, a plate material made of glass selected from, for example, soda-lime glass, aluminosilicate glass, borosilicate glass, fluoroglass, chalcogen glass, alkali-free glass, and quartz glass may be prepared.

[0039] As shown in Figure 5B, a through hole 4 is formed in the glass substrate 10, penetrating the glass substrate 10 in the thickness direction. In addition, a recess pattern 10g is formed on the first surface 10F and the second surface 10S. The recess pattern 10g is a groove that extends linearly on the surface of the glass substrate 10 and has a predetermined path when viewed from above (see Figure 3). The recess pattern 10g may be a groove-like depression or recess. In the manufacturing method of the wiring board of this embodiment, the recess pattern 10g is formed on at least one of the two main surfaces (first surface 10F and second surface 10S) of the glass substrate 10 that are opposite each other in the thickness direction.

[0040] Thus, in the manufacturing method of the wiring board of this embodiment, preparing the glass substrate 10 may include forming a through hole 4 that penetrates between the first surface 10F and the second surface 10S of the glass substrate 10. Furthermore, preparing the glass substrate 10 may include forming a linearly extending recess pattern 10g on at least one of the two main surfaces of the glass substrate 10 (for example, the first surface 10F).

[0041] The through-holes 4 and recessed patterns 10g may be formed by any method. For example, as shown in Figure 5B, an etching mask EM with openings EMO corresponding to the locations on the surface of the glass substrate 10 where the through-holes 4 and recessed patterns 10g are intended to be formed is formed on the first surface 10F and the second surface 10S. Then, the portion of the glass substrate 10 exposed to the openings EMO is removed by dry etching using, for example, carbon tetrafluoride (CF4), sulfur hexafluoride (SF6), or trifluoromethane (CHF3) as the etching gas. As a result, the through-holes 4 and recessed patterns 10g may be formed. After the formation of the through-holes 4 and recessed patterns 10g, the etching mask EM may be removed using a suitable release agent.

[0042] The through-holes 4 and recessed patterns 10g may be formed by wet etching. For example, the through-holes 4 and recessed patterns 10g may be formed by irradiating the glass substrate 10 with laser light (not shown), such as a helium-neon laser, to form modified areas at predetermined locations, and then removing the modified areas by immersion in an etching solution containing hydrogen fluoride, for example. Furthermore, the through-holes 4 and recessed patterns 10g may be formed by the laser light irradiation itself or by drilling, or by a combination of these methods.

[0043] After the formation of the through-holes 4 and recess patterns 10g, preferably, a metal oxide film (not shown), such as tin oxide or zinc oxide, is formed on the entire surface of the glass substrate 10 and the entire inner wall surface exposed to the through-holes 4 and recess patterns 10g, for example, by chemical vapor deposition. Forming a metal oxide film can improve the adhesion between the glass and the metal.

[0044] As shown in Figures 5C to 5E, a conductive layer 21 is formed on the first surface 10F of the glass substrate 10, and a conductive layer 22 is formed on the second surface 10S. At least the conductive layer 21 includes a wiring pattern such as the wiring pattern 211 shown in Figure 5E. That is, the manufacturing method of the wiring substrate of the embodiment includes forming a wiring pattern such as the wiring pattern 211 so as to be exposed on the surface of the glass substrate (e.g., the first surface 10F).

[0045] Conductor layers 21 and 22 may be formed by any method for forming conductor layers. As an example, Figures 5C to 5E show a formation method using a semi-additive method. Specifically, as shown in Figure 5C, first, a first metal film 20a made of a suitable metal such as copper or nickel is formed on the entire surface of the glass substrate 10 and on the entire inner wall surface of the glass substrate 10 exposed to the through-holes 4 or recessed patterns 10g, for example, by sputtering or electroless plating.

[0046] Then, a plating resist PR for wiring formation is formed on the first metal film 20a on the first surface 10F, having openings PRO corresponding to predetermined conductor patterns such as wiring patterns 211, 212 and conductor pads 21p (see Figure 5E). In the example of Figure 5C, a plating resist PR having openings PRO corresponding to predetermined conductor patterns such as wiring patterns 221, 222 and conductor pads 22p (see Figure 5E) is formed on the first metal film 20a on the second surface 10S. The openings PRO are provided such that through holes 4 and recessed patterns 10g are exposed within each opening PRO. Preferably, the openings PRO are provided such that the through holes 4 and recessed patterns 10g are exposed entirely within each opening PRO.

[0047] As shown in Figure 5D, a second metal film 20b made of a suitable metal such as copper or nickel is formed within the opening PRO of the plating resist PR. Figure 5D is an enlarged view of the state after the formation of the second metal film 20b in the VD section shown in Figure 5C. The second metal film 20b is formed, for example, by electroplating using the first metal film 20a as a power supply layer. The second metal film 20b fills the portion of the recess pattern 10g inside the first metal film 20a, and the entire recess pattern 10g is filled with the conductor 20 including the first metal film 20a and the second metal film 20b within the recess pattern 10g. The second metal film 20b is also formed within the opening PRO that overlaps the recess pattern 10g, and the opening PRO overlapping the recess pattern 10g is partially filled with the second metal film 20b. A second metal film 20b that fills the entire opening PRO overlapping the recess pattern 10g may also be formed.

[0048] As a result, the wiring pattern 211 is formed by the conductive material 20 filling the recessed pattern 10g and the opening PRO. That is, forming the wiring pattern in the manufacturing method of the wiring substrate of the embodiment may include filling the recessed pattern, which is provided on the first surface of the glass substrate and extends linearly, with a conductive material. Furthermore, forming the wiring pattern in the manufacturing method of the wiring substrate of the embodiment may include forming a plating resist for wiring formation on the first surface of the glass substrate, which has an opening that overlaps the recessed pattern in a plan view. Moreover, forming the wiring pattern in the manufacturing method of the wiring substrate of the embodiment may include at least partially filling the opening of the plating resist for wiring formation with the conductive material that fills the recessed pattern.

[0049] On the other hand, the second metal film 20b fills the portion of the through-hole 4 that is inside the first metal film 20a, so that the entire through-hole 4 is filled with the conductor 41, which includes the first metal film 20a and the second metal film 20b within the through-hole 4. Thus, the method for manufacturing the wiring board of this embodiment may further include filling the through-hole 4 with the conductor 41, along with filling the recessed pattern 10g with the conductor 20. The second metal film 20b is also formed in the opening PRO that overlaps the through-hole 4, so that the opening PRO that overlaps the through-hole 4 is at least partially filled with the second metal film 20b.

[0050] Although not shown in Figure 5D, a second metal film is also formed within the opening PRO of the plating resist PR on the second surface 10S side of the glass substrate 10 (see Figure 5C). As a result, the through-holes 4 and recessed patterns 10g are filled with a conductor containing the first metal film 20a and the second metal film.

[0051] After the formation of the second metal film 20b, the plating resist PR is removed using an appropriate stripping agent. Subsequently, the portion of the first metal film 20a not covered by the second metal film 20b is removed, for example, by quick etching.

[0052] As a result of the partial removal of the first metal film 20a, a conductor layer 21 is obtained on the first surface 10F of the glass substrate 10, as shown in Figure 5E, which includes a conductor layer 21 containing a set of predetermined conductor patterns that are separated from each other, such as wiring patterns 211, 212, and conductor pads 21p. Similarly, a conductor layer 22 is obtained on the second surface 10S of the glass substrate 10, which includes a set of predetermined conductor patterns that are separated from each other, such as wiring patterns 221, 222, and conductor pads 22p.

[0053] The wiring patterns 211 and 212 protrude upward from the first surface 10F of the glass substrate 10. On the other hand, the wiring patterns 221 and 222 formed on the second surface 10S of the glass substrate 10 protrude upward (outside the glass substrate 10) from the second surface 10S of the glass substrate 10. In Figure 5D, the second metal film 20b that filled the opening PRO overlapping the recessed pattern 10g constitutes the protruding portions (second portions) of the wiring patterns 211 and 212 from the first surface 10F. Also, in Figure 5D, the second metal film 20b that filled the opening PRO overlapping the through hole 4 constitutes the conductor pad 21p.

[0054] As shown in Figure 5F, the manufacturing method of the wiring board of the embodiment includes forming an insulating layer 31 on the first surface 10F of the glass substrate 10 that covers wiring patterns such as wiring patterns 211 and 212. In the example of Figure 5F, an insulating layer 33 covering wiring patterns 221 and 222 is formed on the second surface 10S of the glass substrate 10. The insulating layers 31 and 33 are formed by laminating a resin film, for example, made of epoxy resin, onto both sides of the glass substrate 10 and then thermocompressing them. Through holes are formed in the insulating layers 31 and 33 at the locations where via conductors 3a are to be formed, for example by irradiation with carbon dioxide laser light. Then, for example, a conductor layer 23 is formed on the insulating layer 31 and a conductor layer 24 is formed on the insulating layer 33 by a semi-additive method. Via conductors 3a are formed in the through holes of the insulating layers 31 and 33, respectively.

[0055] As shown in Figure 5G, two more sets of insulating layers 32 and conductive layers 23 are formed on the first surface 10F side of the glass substrate 10. The insulating layers 32 may be formed using the same method as for forming the insulating layer 31. The conductive layers 23 that are further formed are formed using the same method as for forming the conductive layer 23 on the insulating layer 31. Via conductors 3a are formed on each insulating layer 32. Similarly, two more sets of insulating layers 33 and conductive layers 24 are formed on the second surface 10S side of the glass substrate 10. Via conductors 3a are formed on each insulating layer 33 that are formed.

[0056] Furthermore, a solder resist layer SR1 is formed on the outermost surface of the first surface 10F of the glass substrate 10, and a solder resist layer SR2 is formed on the outermost surface of the second surface 10S. Solder resist layers SR1 and SR2 are formed by spraying or laminating a resin film, such as a photosensitive epoxy resin or polyimide resin, respectively. Conductor pads 23p or 24p are exposed or openings are formed in each formed solder resist layer, for example, by photolithography. A surface protective film (not shown) made of any metal or heat-resistant preflux may be formed on the surface of the exposed conductor pads 23p and 24p by electroless plating, solder leveling, or spray coating. By going through the above steps, the wiring board 1 shown in the example of Figure 1 is completed.

[0057] <First modified example of the method for manufacturing a wiring board according to the embodiment> Referring to Figures 6A to 6D, a first modified example of the method for manufacturing a wiring board of the embodiment will be described, using as an example the case in which a wiring board including the modified wiring pattern 211 shown in Figure 4B is manufactured. In the following description of the first modified example, the descriptions of steps similar to those already described with reference to Figures 5A to 5G will be simplified or omitted as appropriate.

[0058] As shown in Figure 6A, in the first modified example of the wiring board manufacturing method, a glass substrate 10 having a first surface 10F and a second surface 10S is also prepared. The glass substrate 10 prepared in this modified example already includes a conductor (through conductor) 41 that penetrates between the first surface 10F and the second surface 10S. The conductor 41 fills the through hole 4 that penetrates the glass substrate 10. The conductor 41 may consist of an electroless plating film or a sputtering film and an electroplating film made of a suitable metal such as copper or nickel. The conductor 41 may include, for example, a third metal film 20c that is in contact with the inner wall surface of the glass substrate 10 exposed to the through hole 4, and a fourth metal film 20d that fills the portion of the through hole 4 inside the third metal film 20c, as shown in Figure 6D, which will be referenced later.

[0059] As shown in Figure 6B, recess patterns 10g similar to those formed by the method described with reference to Figures 5A to 5G are formed on the first surface 10F and the second surface 10S. In this modified example as well, the recess patterns 10g are formed on at least one of the first surface 10F and the second surface 10S that are opposite each other in the thickness direction of the glass substrate 10. Thus, in this modified example, preparing the glass substrate may include forming the recess patterns on the surface of the glass substrate (for example, the first surface 10F).

[0060] In the example of the method for forming the recessed pattern 10g shown in Figure 6B, an etching mask DM for recess formation is used. Specifically, a mask DM having an opening DMO corresponding to the area on the surface of the glass substrate 10 where the recessed pattern 10g is intended to be formed is formed on the first surface 10F and the second surface 10S. Both end faces of the conductor 41 that penetrates the glass substrate 10 are covered with the etching mask DM. Then, by dry etching using, for example, CF4, SF6, or CHF3 as the etching gas, a portion of the glass substrate 10 near the surface exposed to the opening DMO is removed.

[0061] As a result of removing a portion of the surface near the opening DMO, a recessed pattern 10g is formed. The etching mask DM may be removed using an appropriate release agent after the formation of the recessed pattern 10g. The method for forming the recessed pattern 10g is not limited to dry etching; the recessed pattern 10g may also be formed by wet etching or other methods as described above.

[0062] Thus, forming the recessed pattern in this modified example may include forming a mask on the surface of the glass substrate (e.g., the first surface 10F) that covers the end face of a through-conductor that penetrates the glass substrate and is exposed on the surface of the glass substrate (e.g., the first surface 10F). In this case, a mask having an opening is formed at the location where the recessed pattern is formed. Furthermore, forming the recessed pattern in this modified example may also include removing a portion of the glass substrate near the surface exposed to the opening of the mask, thereby recessing the portion of the glass substrate's surface (e.g., the first surface 10F) that is exposed to the opening of the mask.

[0063] After the recess pattern 10g is formed, a wiring pattern such as the wiring pattern 211 (see Figure 6D) is formed on the surface of the glass substrate 10. First, as shown in Figure 6C, a first metal film 20a is formed on the entire surface of the glass substrate 10, on the surface of the conductor 41 that is exposed to the surface of the glass substrate 10, and on the inner wall surface of the glass substrate 10 that is exposed to the recess pattern 10g. That is, in this modified example, forming the wiring pattern may include forming the first metal film inside the recess pattern, on the surface of the glass substrate (e.g., the first surface 10F), and on the surface of the conductor penetrating the glass substrate that is exposed to the surface of the glass substrate (e.g., the first surface 10F).

[0064] Then, a plating resist PR for wiring formation, having openings PRO corresponding to predetermined conductor patterns such as wiring patterns 211 and conductor pads 21p (see Figure 6D), is formed on the first metal film 20a on the first surface 10F. In the example of Figure 6C, a plating resist PR with openings PRO is also formed on the first metal film 20a on the second surface 10S. The openings PRO are provided such that, in a plan view, each opening PRO overlaps with the recessed pattern 10g, exposing the recessed pattern 10g within the opening PRO. In the example of Figure 6C, each opening PRO is provided to have a width greater than the width of the recessed pattern 10g exposed within each opening PRO. Thus, in the manufacturing method of the wiring substrate of this modified example, forming a wiring pattern may include forming a plating resist having openings that overlap the recessed pattern in a plan view on a metal film formed on the surface of a glass substrate.

[0065] As shown in Figure 6D, a second metal film 20b made of a suitable metal such as copper or nickel is formed within the opening PRO of the plating resist PR. Figure 6D is an enlarged view of the state after the formation of the second metal film 20b in the VID portion shown in Figure 6C. The second metal film 20b is formed, for example, by electroplating using the first metal film 20a as a power supply layer. The second metal film 20b fills the portion of the recess pattern 10g inside the first metal film 20a, and the entire recess pattern 10g is filled with a conductor 20 including the first metal film 20a and the second metal film 20b within the recess pattern 10g. The second metal film 20b is also formed within the opening PRO that overlaps the recess pattern 10g. The opening PRO that overlaps the recess pattern 10g is partially filled with the conductor 20 (specifically the second metal film 20b). A second metal film 20b that fills the entire opening PRO that overlaps the recess pattern 10g may also be formed.

[0066] As a result of the formation of the second metal film 20b, a wiring pattern 211 is formed that fills the recessed pattern 10g and the opening PRO. In the example shown in Figure 6D, an opening PRO having a width greater than the width of the recessed pattern 10g is formed on the recessed pattern 10g. Therefore, a wiring pattern 211 is formed that has a wider width in the portion protruding from the first surface 10F of the glass substrate 10 than in the portion within the recessed pattern 10g. Thus, forming the wiring pattern in this modified example may include filling the openings in the plating resist for wiring formation with a conductor that fills the recessed pattern, at least partially.

[0067] In this modified example of the wiring board manufacturing method, as shown in Figure 6D, a second metal film 20b is formed inside the opening PRO that overlaps with the conductor 41 filling the through hole 4 in a plan view, on top of the portion of the first metal film 20a that covers the conductor 41. The opening PRO that overlaps with the conductor 41 is filled at least partially with the second metal film 20b. A conductor pad 21p is formed, consisting of the first metal film 20a covering the conductor 41 and the second metal film 20b on the first metal film 20a.

[0068] Although not shown in Figure 6D, a second metal film may also be formed on the second surface 10S (see Figure 6C) of the glass substrate 10, within the opening PRO of the plating resist PR, and a wiring pattern that fills the recessed pattern 10g may be formed.

[0069] After the formation of the second metal film 20b, the plating resist PR is removed using a suitable stripping agent. Subsequently, the portion of the first metal film 20a not covered by the second metal film 20b is removed, for example, by quick etching. As a result, conductive layers containing individually separated desired conductive patterns, such as wiring patterns 211 and conductive pads 21p, are obtained on both sides of the glass substrate 10. After the formation of conductive layers on both sides of the glass substrate 10, if necessary, a predetermined number of conductive layers and insulating layers may be formed in the manner described with reference to Figures 5F and 5G, and each solder resist layer may be formed.

[0070] <Second Modification of the Method for Manufacturing a Wiring Board of an Embodiment> Referring to Figures 7A to 7C, a second modified example of the method for manufacturing a wiring board of the embodiment will be described, using as an example the case in which a wiring board including the modified wiring pattern 211 shown in Figure 4C is manufactured. In the following description of the second modified example, the explanation of steps similar to those already described with reference to Figures 5A to 5G or Figures 6A to 6D will be simplified or omitted as appropriate.

[0071] In the second modified method for manufacturing a wiring board, as shown in Figure 7A, a glass substrate 10 having a first surface 10F and a second surface 10S is prepared, and a recessed pattern 10g is formed on the glass substrate 10. Similar to the first modified method for manufacturing a wiring board, a glass substrate 10 including a conductor (through-conductor) 41 that penetrates between the first surface 10F and the second surface 10S may be prepared. The recessed pattern 10g is formed on at least the first surface 10F, for example, by the method described with reference to Figure 6B.

[0072] After the formation of the recess pattern 10g, a wiring pattern such as the wiring pattern 211 (see Figure 7C) is formed on the surface of the glass substrate 10. First, a plating resist PR for wiring formation, having an opening PRO corresponding to a predetermined conductor pattern such as the wiring pattern 211, is formed on the first surface 10F. In the example of Figure 7A, a plating resist PR with an opening PRO is also formed on the second surface 10S. The openings PRO are arranged so that the recess pattern 10g is exposed within the opening PRO, with each opening PRO overlapping the recess pattern 10g in a plan view. Thus, forming the wiring pattern in this modified example may include forming a plating resist on the surface of the glass substrate (e.g., the first surface 10F) that has an opening that overlaps the recess pattern formed on the surface of the glass substrate in a plan view.

[0073] After the formation of the plating resist PR, a first metal film 20a is formed on the area of ​​the glass substrate 10 surface not covered by the plating resist PR, the exposed surface of the conductor 41 to the surface of the glass substrate 10, the inner wall surface of the glass substrate 10 exposed to the recess pattern 10g, and the surface of the plating resist PR. The first metal film 20a is made of a suitable metal such as copper or nickel, and may be formed by sputtering or electroless plating, for example. As shown in Figure 7A, the inner wall surface of the opening PRO of the plating resist PR is covered by the first metal film 20a, and the upper surface PRa of the plating resist PR may also be covered. Thus, in this modified example, forming the wiring pattern may include forming a metal film inside the recess pattern, on the surface of the plating resist formed on the surface of the glass substrate, and on the exposed surface of the conductor penetrating the glass substrate to the surface of the glass substrate (e.g., the first surface 10F).

[0074] As shown in Figure 7B, a second metal film 20b made of a suitable metal such as copper or nickel is formed within the opening PRO of the plating resist PR. Figure 7B is an enlarged view of the state after the formation of the second metal film 20b in the VIIB section shown in Figure 7A. The second metal film 20b is formed, for example, by electroplating using the first metal film 20a as a power supply layer. With the formation of the second metal film 20b, the entire recess pattern 10g is filled with the conductor 20, which includes the first metal film 20a and the second metal film 20b within the recess pattern 10g. The second metal film 20b is also formed within the opening PRO that overlaps the recess pattern 10g. The second metal film 20b is formed surrounded by the first metal film 20a that covers the inner wall surface of the opening PRO. The opening PRO that overlaps the recess pattern 10g in a plan view is filled with the first metal film 20a and the second metal film 20b.

[0075] In the example shown in Figure 7B, since the first metal film 20a is also formed on the upper surface PRa of the plating resist PR, the second plating film 20b is formed throughout the entire interior of the opening PRO and also on the upper surface PRa of the plating resist PR. That is, the first plating film 20a and the second plating film 20b completely fill the opening PRO and further cover the upper surface PRa of the plating resist PR. Alternatively, the second metal film 20b may be formed to partially fill the opening PRO that overlaps the recess pattern 10g.

[0076] In this modified method for manufacturing the wiring board, as shown in Figure 7B, a second metal film 20b is formed on top of a first metal film 20a inside the opening PRO that overlaps with the conductor 41 filling the through hole 4 in a plan view. The second metal film 20b is formed surrounded by the first metal film 20a that covers the inner wall surface of the opening PRO. The opening PRO that overlaps with the conductor 41 in a plan view is filled with the first metal film 20a and the second metal film 20b.

[0077] After the formation of the second metal film 20b, the first metal film 20a and the second metal film 20b covering the upper surface PRa of the plating resist PR are removed, for example, by chemical mechanical polishing. The portion near the upper surface PRa of the plating resist PR may also be removed along with the removed portions of the first plating film 20a and the second plating film 20b.

[0078] As shown in Figure 7C, a wiring pattern 211 is obtained, which consists of a conductor composed of a recessed pattern 10g and a first metal film 20a and a second metal film 20b that fill the openings PRO on the recessed pattern 10g. A conductive pad 21p is also obtained, which consists of the first metal film 20a and the second metal film 20b that fill the openings PRO on the conductor 41. Both the portion of the wiring pattern 211 within the recessed pattern 10g and the portion protruding from the first surface 10F of the glass substrate 10 are composed of the first metal film 20a and the second metal film 20b. Thus, in the manufacturing method of the wiring substrate of this modified example, forming the wiring pattern may include at least partially filling the openings of the plating resist with the conductor that fills the recessed pattern.

[0079] After removing the first metal film 20a and the second metal film 20b on the plating resist PR, the remaining plating resist PR is removed using an appropriate stripping agent. In the second modified method for manufacturing a wiring substrate, the wiring pattern on the surface of the glass substrate 10 is formed without etching, which makes it easier to form fine wiring patterns.

[0080] Although not shown in Figures 7B and 7C, a second metal film may also be formed within the opening PRO of the plating resist PR on the second surface 10S (see Figure 7A) of the glass substrate 10. Furthermore, the first metal film 20a and the second metal film covering the upper surface PRa of the plating resist PR may be removed, and any remaining plating resist PR may also be removed.

[0081] By removing the first metal film 20a and the second metal film 20b on the plating resist PR, a conductor layer containing a desired conductor pattern, such as electrically isolated wiring patterns 211 and conductor pads 21p, is obtained. After the formation of conductor layers on both sides of the glass substrate 10, a predetermined number of conductor layers and insulating layers may be formed as needed, in the manner described with reference to Figures 5F and 5G, and each solder resist layer may be formed.

[0082] The wiring boards of the embodiments are not limited to the structures illustrated in each drawing, nor to the structures, shapes, and materials illustrated herein. As stated above, the wiring boards of the embodiments may have any laminated structure. The wiring boards of the embodiments may have any number of conductor layers and insulating layers. A solder resist layer may not be provided. Each conductor layer may include any conductor pattern. Wiring patterns that are partially embedded in the glass substrate may be formed on only one side of the glass substrate. Furthermore, there may be one or more wiring patterns that are partially embedded in the glass substrate.

[0083] The manufacturing method of the wiring board of the embodiment is not limited to the method described with reference to the drawings. For example, the method for forming each insulating layer and the conductive layer formed on each insulating layer is not limited to the method described with reference to Figures 5A to 5G. Each conductive layer may be formed by a method other than the semi-additive method, such as the fully additive method, or by a method similar to the method for forming a conductive layer formed on the surface of a glass substrate. The manufacturing method of the wiring board of the embodiment may include any additional steps other than those described above, and some of the described steps may be omitted. [Explanation of Symbols]

[0084] 1 Wiring board 10 Glass substrate 10F 1st page 10S 2nd page 10g recessed pattern 20 Conductors filling the recessed patterns 20a First metal film 20b Second metal film 21-24 Conductor layer 21p, 21pp, 22p, 23p, 24p Conductor Pads Wiring patterns 211, 212, 221, 222 21a Part 1 of the wiring pattern 21b Part 2 of the wiring pattern 21c The second side and the opposite side of the glass substrate in the wiring pattern 31-33 Insulating layer 4 through holes 41. Conductor filling through-holes (through-hole conductor) 4a The first surface of the glass substrate in the conductive material Etching mask for forming DM recesses Etching mask opening for DMO recess formation PR Plating Resist PRO Plating Resist Aperture Thickness of the first part of the wiring pattern Ta Thickness of the second part of the Tb wiring pattern Width of the first part of the wiring pattern Width of the second part of the Wb wiring pattern

Claims

1. A glass substrate having a first surface and a second surface which is the opposite surface of the first surface, and a through hole that penetrates between the first surface and the second surface, A conductor filling the aforementioned through hole, The wiring pattern exposed on the first surface, An insulating layer laminated on the first surface and covering the wiring pattern, A wiring board including, The glass substrate has a linear recess pattern extending from the first surface, The recessed pattern is filled with the wiring pattern.

2. A wiring board according to claim 1, further comprising a conductor pad provided between the conductor and the insulating layer.

3. The wiring board according to claim 2, wherein the conductor pad includes a metal film formed substantially parallel to the first surface on the conductor.

4. A wiring board according to claim 1, wherein the wiring pattern includes a first portion that fills the recessed pattern and a second portion that protrudes from the first surface.

5. The wiring board according to claim 4, wherein the width of the first portion and the width of the second portion are substantially the same.

6. The wiring board according to claim 4, wherein the width of the second portion is greater than the width of the first portion.

7. The wiring board according to claim 4, wherein the thickness of the first portion and the thickness of the second portion are different.

8. The wiring board according to claim 4, wherein the thickness of the first portion and the thickness of the second portion are substantially the same.

9. A wiring board according to claim 4, The wiring pattern is composed of a first metal film in contact with the inner wall surface of the glass substrate exposed in the recess pattern, and a second metal film surrounded by the first metal film. A portion of the first metal film protrudes from the first surface and constitutes the side surface of the second portion.

10. The wiring board according to claim 4, wherein, in the thickness direction of the glass substrate, the distance between the surface on the first side of the conductor and the first surface is smaller than the distance between the surface on the opposite side of the wiring pattern and the first surface.

11. A glass substrate is prepared having a first surface and a second surface opposite to the first surface, A wiring pattern is formed so as to be exposed on the first surface of the glass substrate, An insulating layer is formed on the first surface to cover the wiring pattern, A method for manufacturing a wiring board, including, Forming the aforementioned wiring pattern is This includes filling the linearly extending recessed patterns provided on the first surface with a conductor.

12. A method for manufacturing a wiring board according to claim 11, wherein the wiring pattern is formed by A plating resist having an opening that overlaps the recess pattern in a plan view is formed on the first surface, This includes filling the opening at least partially with the conductor that fills the recess pattern.

13. A method for manufacturing a wiring board according to claim 11, wherein the glass substrate is prepared To form a through hole that penetrates between the first surface and the second surface, This includes forming the recess pattern on the first surface.

14. A method for manufacturing a wiring board according to claim 13, further comprising filling the recessed pattern with the conductor and filling the through-holes with the conductor.

15. A method for manufacturing a wiring board according to claim 11, The glass substrate includes a through-conductor that penetrates between the first surface and the second surface. Preparing the glass substrate includes forming the recess pattern on the first surface of the glass substrate. Forming the aforementioned recessed pattern means A mask is formed on the first surface, having an opening at the location where the recess pattern is formed, and covering the through-conductor. The portion of the first surface that is exposed to the opening is recessed, It includes.

16. A method for manufacturing a wiring board according to claim 15, wherein the wiring pattern is formed by A metal film is formed inside the recess pattern, on the first surface, and on the surface of the through-conductor that is exposed to the first surface. A plating resist having an opening that overlaps the recess pattern in a plan view is formed on the metal film, This includes filling the openings in the plating resist with the conductor that fills the recess pattern.

17. A method for manufacturing a wiring board according to claim 15, wherein the wiring pattern is formed by A plating resist having an opening that overlaps the recess pattern in a plan view is formed on the first surface, A metal film is formed inside the recess pattern, on the surface of the plating resist, and on the surface of the through-conductor that is exposed to the first surface. This includes filling the openings in the plating resist with the conductor that fills the recess pattern.

Images