JP7147197B2 - Wiring board and method for manufacturing wiring board - Google Patents

Description

The present disclosure relates to a wiring board and a method for manufacturing the wiring board.

2. Description of the Related Art As semiconductor devices such as light-emitting devices and light-receiving devices are miniaturized and have higher quality and higher precision, wiring substrates are being developed. A wiring substrate having through electrodes is used as a relay substrate (interposer). An organic resin material is used for the insulating layer in the wiring board. The organic resin material can be embedded between wirings without gaps, and has excellent insulating properties. Patent Documents 1 and 2 disclose a semiconductor device including a wiring substrate using an organic resin material.

Retable 2010-074038 JP 2017-139489 A

However, in the case of conventional wiring boards, an insulating layer using an organic resin material may absorb light in the visible region (for example, a wavelength region of 350 nm or more and 500 nm or less) from the outside or from the ultraviolet region emitted by the light emitting element. As a result, the insulating layer may deteriorate and the film thickness of the insulating layer may decrease. As a result, the connection between the semiconductor element and the wiring board may become unstable. This affects long-term reliability when semiconductor devices and wiring boards are used as electronic components.

In view of such problems, one object of the embodiments of the present disclosure is to provide a highly reliable wiring board having light resistance.

According to one embodiment of the present disclosure, a substrate having a first side and a second side opposite the first side, an insulating layer provided on the first side of the substrate, and a light emitting layer provided on the insulating layer and a semiconductor element that receives or receives light, and that the insulating layer has a transmittance of 80% or more at a wavelength of 365 nm and a visible light transmittance of 90% or more in a wavelength region of 380 nm or more and 780 nm or less. A wiring substrate is provided.

In the above wiring board, the insulating layer may be an organic insulating layer.

In the above wiring board, the insulating layer may contain a compound having an oxime ester structure.

In the above wiring board, the insulating layer may contain a compound having a carbazole group or a phenylsulfide group.

The wiring substrate may further include a plurality of first wirings provided on the same plane on the first surface side of the substrate, and the insulating layer may be provided between the plurality of first wirings.

The above-described wiring substrate includes a plurality of second wirings provided on the same plane on the second surface side of the substrate, through holes penetrating the substrate, and through electrodes provided in the through holes. One of the one wiring and one of the plurality of second wirings may be electrically connected by a through electrode.

In the above wiring board, the difference between the refractive index of the substrate and the refractive index of the insulating layer may be 0.2 or less.

In the above wiring board, the substrate may be glass.

According to one embodiment of the present disclosure, wiring is formed on a substrate, an organic insulating layer composition containing a compound having an oxime ester structure is applied on the substrate and the wiring, and the organic insulating layer composition is photocured. A method for manufacturing a wiring substrate is provided, which comprises forming an insulating layer using a method of forming an insulating layer, forming an opening on a wiring in the insulating layer, and connecting the wiring and a semiconductor element that emits light or receives light through the opening.

In the method for producing a wiring board described above, the content of the compound having an oxime ester structure in the composition for an organic insulating layer may be 5% by mass or less.

According to an embodiment of the present disclosure, it is possible to provide a highly reliable wiring board having light resistance.

1 is a top view illustrating a wiring board according to an embodiment of the present disclosure; FIG. 1 is a cross-sectional view illustrating a wiring board according to an embodiment of the present disclosure; FIG. FIG. 4A is a cross-sectional view illustrating a method for manufacturing a wiring board according to an embodiment of the present disclosure; FIG. 4A is a cross-sectional view illustrating a method for manufacturing a wiring board according to an embodiment of the present disclosure; FIG. 4A is a cross-sectional view illustrating a method for manufacturing a wiring board according to an embodiment of the present disclosure; FIG. 4A is a cross-sectional view illustrating a method for manufacturing a wiring board according to an embodiment of the present disclosure; FIG. 4A is a cross-sectional view illustrating a method for manufacturing a wiring board according to an embodiment of the present disclosure; 1 is a perspective view illustrating an electronic device including a wiring board according to an embodiment of the present disclosure; FIG. 1 is a transmittance spectrum of Example 1. FIG. 1 is a cross-sectional view illustrating a wiring board according to an embodiment of the present disclosure; FIG. 1 is a cross-sectional view illustrating a wiring board according to an embodiment of the present disclosure; FIG.

Hereinafter, wiring boards and the like according to respective embodiments of the present disclosure will be described in detail with reference to the drawings. Each embodiment shown below is an example of the embodiments of the present disclosure, and the present disclosure should not be construed as being limited to these embodiments. In the drawings referred to in this embodiment, the same reference numerals or similar reference numerals may be assigned to the same parts or parts having similar functions, and repeated description thereof may be omitted. Also, the dimensional ratios in the drawings may differ from the actual ratios for the convenience of explanation, and a part of the configuration may be omitted from the drawings.

<First embodiment>
(1-1. Configuration of Wiring Board 100)
Details of the wiring board 100 will be described below. FIG. 1 shows a top view of the wiring substrate 100. As shown in FIG. FIG. 2 shows a cross-sectional view of the wiring board 100 along A1-A2. As shown in FIGS. 1 and 2, the wiring substrate 100 includes a substrate 110, a through electrode 120, a wiring 130, an insulating layer 140, a wiring 150, a bump electrode 160, and a wiring 130 on the first surface 110-1 side of the substrate 110. A semiconductor device 200 is included. Wiring substrate 100 also includes wiring 230 , insulating layer 240 , wiring 250 , and bump electrode 260 on the second surface 110 - 2 side of substrate 110 opposite to first surface 110 - 1 .

The type of the substrate 110 is not particularly limited, but it is preferable that the difference between the refractive index of the substrate 110 and the insulating layer 140 described later is 0.2 or less. For example, a material that transmits light is used for the substrate 110 . Specifically, as the substrate 110, a glass substrate such as a soda glass substrate, an alkali-free glass substrate, or a quartz glass substrate is used. For example, the quartz glass substrate is configured to have a transmittance of 90% for light in the wavelength range of 380 nm to 780 nm in the visible region.

Further, the substrate 110 is provided with a through hole 115 penetrating from the first surface 110-1 to the second surface 110-2. The through hole 115 when viewed from above may have a circular shape. Moreover, the width of the through hole 115 may be appropriately set within a range of 10 μm or more and less than 250 μm.

The through electrode 120 is provided in the through hole 115 . A low resistance material is used for the through electrode 120 . For example, copper (Cu) is used for the through electrode 120 . Note that the through electrode 120 is not limited to copper, and a material containing gold (Au), silver (Ag), nickel (Ni), or tin (Sn) may be used. Wiring 130 (wiring 130-1) and wiring 230 (wiring 230-1) are electrically connected by using through electrode 120. FIG.

The wiring 130 is provided in contact with the first surface 110 - 1 of the substrate 110 and the through electrode 120 . A plurality of wirings 130 are provided on the same plane, such as wirings 130 - 1 and 130 - 2 , and are electrically connected to through electrodes 120 . For example, copper (Cu) is used for the wiring 130 . Note that the wiring 130 is not limited to copper (Cu), and may be gold (Au), silver (Ag), platinum (Pt), tungsten (W), aluminum (Al), nickel (Ni), or the like. good. Note that the wiring 130 does not necessarily have to be in contact with the first surface 110-1 of the substrate 110. FIG. At this time, an insulating layer different from the insulating layer 140 may be provided between the substrate 110 and the wiring 130 . At this time, an inorganic insulating material such as silicon oxide or silicon nitride may be used for the insulating layer.

The insulating layer 140 is provided on the first surface 110 - 1 of the substrate 110 and the through electrodes 120 . The insulating layer 140 is also provided between a plurality of wirings 130 (the wirings 130-1 and 130-2 shown in FIG. 2). An organic insulating layer containing an organic resin material is used for the insulating layer 140 . For example, acrylic resin is used for the insulating layer 140 .

Insulating layer 140 preferably contains a compound having a carbazole group or a phenylsulfide group together with the acrylic resin. For example, a compound having a carbazole group has a structure represented by chemical formula (1).

The content of the compound having a carbazole group or a phenylsulfide group in insulating layer 140 is preferably 0.1% by mass or more and 5% by mass or less. A compound having a carbazole group or a phenyl sulfide group has the property of absorbing light in the vicinity of a wavelength of 400 nm (wavelength of 350 nm to 500 nm), and has a complementary color (specifically, yellow or orange). , in the case of the present embodiment, the content of the above compounds can be reduced. As a result, the insulating layer 140 has a transmittance of 80% or more at a wavelength of 365 nm and a transmittance of 90% or more in the wavelength range of 380 nm or more and 780 nm or less. As a result, the insulating layer 140 has a high transmittance for light in the visible region and a part of the ultraviolet region, so deterioration due to light can be prevented. By preventing deterioration due to light, it is possible to prevent the film thickness of the insulating layer 140 from decreasing.

In the above description, the thickness of the insulating layer 140 is preferably 0.5 μm to 50 μm, preferably 1 μm to 10 μm, more preferably 3 μm to 6 μm. At this time, the transmittance at a wavelength of 365 nm per 1 μm thickness of the insulating layer 140 is 96% or more, and the transmittance in the wavelength range of 380 nm or more and 780 nm or less is 98% or more.

The wiring 150 is provided in the opening 145 of the insulating layer 140 . The wiring 150 is electrically connected to the wiring 130 . A material similar to that of the through electrode 120 is used for the wiring 150 .

Bump electrode 160 is provided on insulating layer 140 and wiring 150 . Tin (Sn), silver (Ag), copper (Cu), or the like is used for bump electrode 160 .

A semiconductor element 200 is provided on the insulating layer 140 . Semiconductor element 200 is electrically connected to bump electrode 160 . At this time, the wiring 130 and the semiconductor element 200 can be electrically connected via the wiring 150 and the bump electrode 160 . The semiconductor element 200 has a function of emitting light or a function of receiving light. For example, when the semiconductor element 200 is used as a light-emitting element, a light-emitting diode (LED) may be used. Alternatively, when the semiconductor element 200 is used as a light receiving element, it may be an optical sensor or a solid-state imaging element. In addition, the semiconductor element 200 may include an element that controls a light emitting element or a light receiving element. The semiconductor element 200 may also include an element (memory) for storing information for controlling the light emitting element or the light receiving element, information obtained by the light receiving element, or the like.

The wiring 230 is provided on the second surface 110 - 2 of the substrate 110 and the through electrodes 120 . A plurality of wirings 230 are provided on the same plane like wirings 230 - 1 and 230 - 2 and are electrically connected to through electrodes 120 . A material similar to that of the wiring 130 may be used for the wiring 230 .

The insulating layer 240 is provided on the second surface 110 - 2 of the substrate 110 and the wiring 230 . The insulating layer 240 is also provided between a plurality of wirings 230 (the wirings 230-1 and 230-2 shown in FIG. 2). The insulating layer 240 uses the same organic insulating material as the insulating layer 140 .

The wiring 250 is provided in the opening 245 of the insulating layer 240 . The wiring 250 is electrically connected to the wiring 230 . A material similar to that of the wiring 150 is used for the wiring 250 .

Bump electrode 260 is provided on insulating layer 240 and wiring 250 . A material similar to that of the bump electrode 160 is used for the bump electrode 260 . Incidentally, the bump electrodes 260 are appropriately connected to other wiring substrates, semiconductor elements, or the like. For example, the bump electrodes 260 may be connected to the printed circuit board 300 .

(1-2. Manufacturing Method of Wiring Board 100)
Next, a method of manufacturing the wiring substrate 100 shown in FIGS. 1 and 2 will be described with reference to FIGS. 3 to 7. FIG.

First, as shown in FIG. 3A, a substrate 110 having a first surface 110-1 and a second surface 110-2 opposite to the first surface 110-1 is used. For example, quartz glass is used for the substrate 110 . In the following description, it is assumed that quartz glass is used for the substrate 110 .

Next, as shown in FIG. 3B, through holes 115 are formed in the substrate 110 . The through-hole 115 is formed, for example, by applying a laser irradiation method (which can be called a laser ablation method) to the substrate 110 . Examples of lasers include excimer lasers, neodymium:YAG lasers (Nd:YAG) lasers, and femtosecond lasers. When an excimer laser is used, light in the ultraviolet region is irradiated. For example, when using xenon chloride in an excimer laser, light with a wavelength of 308 nm is irradiated. Note that the laser irradiation diameter may be 10 μm or more and less than 250 μm. The hole diameter of the through hole 115 can be appropriately set within a range of 10 μm or more and less than 250 μm.

The formation of the through holes 115 is not limited to the laser irradiation method, and dry etching methods such as reactive ion etching and deep reactive ion etching, wet etching, or laser irradiation may be used. and a wet etching method may be used in combination. For example, when wet etching quartz glass, a hydrofluoric acid aqueous solution is used.

Next, as shown in FIG. 4A, through electrodes 120 are formed in the through holes 115 . Copper (Cu), nickel (Ni), gold (Au), silver (Ag), tin (Sn), or the like is used for the through electrode 120 . The through electrodes 120 are formed by plating. For example, the through electrode 120 is made of copper (Cu) formed by plating. An example of a method for forming the through electrode 120 is shown below. First, a copper (Cu) thin film is formed on the sidewall of the through hole 115 by electroless plating. Next, a copper (Cu) film is formed by electroplating using a copper (Cu) thin film as a seed layer. Finally, the through electrode 120 is formed by planarizing the copper (Cu) film by a chemical mechanical polishing (CMP) method.

Next, as shown in FIG. 4B, wirings 130 are formed on the first surface 110-1 of the substrate 110 and the through electrodes 120. Next, as shown in FIG. The wiring 130 is formed by a plating method, a sputtering method, a CVD method, a coating method, a printing method, or the like. For example, the wiring 130 is made of copper (Cu) formed by plating. Also, the wiring 130 is processed into an appropriate shape using a photolithography method and an etching method as appropriate. Note that although the wiring 230 is not shown in FIG. 4B, the wiring 230 may be formed using a material and a method similar to those of the wiring 130 .

Next, an insulating layer 140 is formed on the first surface 110-1 of the substrate 110 and the wiring 130. As shown in FIG. First, as shown in FIG. 5A, an organic insulating layer composition 135, which is a material for forming an insulating layer 140, is formed by a coating method. Specific examples of coating methods include spin coating, spray coating, slit coating, and dip coating. An acrylic resin or the like is used for the organic insulating layer composition 135 .

Next, as shown in FIG. 5B, the organic insulating layer composition 135 is irradiated with light 137 including a wide wavelength range of 300 nm or more and 450 nm or less. As a result, the organic insulating layer composition 135 is cured to form the insulating layer 140 . At this time, the organic insulating layer composition 135 preferably contains a compound having an oxime ester structure as a photopolymerization initiator. Compounds having an oxime ester structure include the following carbazole-type oxime ester initiator (2) and phenylsulfide-type oxime ester initiator (3).

Formula (4) shows the reaction mechanism when the carbazole-type oxime ester initiator (2) among the above compounds is irradiated with light.

As shown in the above formula (4), a methyl radical is generated by irradiating the carbazole-type oxime ester initiator (2) with light. This methyl radical accelerates the polymerization of the organic insulating layer composition 135 .

A photopolymerization initiator having an oxime ester structure has a short-wavelength near-ultraviolet region (specifically, (near 300 nm) is characterized by high sensitivity. Specifically, the content of the photopolymerization initiator containing the compound having an oxime ester structure can be 5% by mass or less relative to the composition for the organic insulating layer.

Here, a functional group such as a carbazole group or a phenylsulfide group contained in the photopolymerization initiator has a property of absorbing light belonging to the near-ultraviolet region to the visible region (for example, a wavelength region of 350 nm to 500 nm). Therefore, when the organic insulating layer composition 135 contains a large amount of a photopolymerization initiator, it has a color (specifically, yellow or orange) corresponding to the complementary color of the wavelength region. On the other hand, by using the photopolymerization initiator of this embodiment, the content of the photopolymerization initiator in the organic insulating layer composition 135 can be suppressed to 5% by mass or less. As a result, the formed insulating layer 140 can have a transmittance of 80% or more at a wavelength of 365 nm and a transmittance of 90% or more in a wavelength range of 380 nm or more and 780 nm or less. That is, by using the insulating layer of the present embodiment, light in the wavelength range of 350 nm to 500 nm is transmitted, so that deterioration of the insulating layer can be prevented. Degradation of the insulating layer may cause a reduction in the thickness of the insulating layer (film thickness reduction), but the problem can be solved by using the insulating layer of this embodiment.

Although the insulating layer 240 is not described above, it is formed using the same material and method as the insulating layer 140 .

Next, as shown in FIG. 6A, an opening 145 is formed in a portion of the insulating layer 140 which overlaps with the wiring 130 . The opening 145 is formed using, for example, photolithography and etching. In FIG. 5B, the entire organic insulating layer composition 135 is irradiated with light 137. However, by irradiating light with a mask provided in a portion corresponding to the opening 145, the opening 145 can be removed. may be formed. Thereby, the number of manufacturing steps of the wiring board can be reduced.

Next, as shown in FIG. 6B, a wiring 150 is formed in the opening 145. Next, as shown in FIG. The wiring 150 is formed by a plating method, a CVD method, a sputtering method, a printing method, or the like. Copper (Cu), nickel (Ni), gold (Au), silver (Ag), tin (Sn), palladium (Pd), or the like is used for the wiring 150 . For example, the wiring 150 uses a copper (Cu) film formed by a plating method. Although the wiring 250 is not described above, the wiring 250 is formed using the same material and method as the wiring 150 .

Next, as shown in FIG. 7, bump electrodes 160 are formed on the wirings 150 . The bump electrode 160 contains tin (Sn), silver (Ag), copper (Cu), lead (Pb), gold (Au), nickel (Ni), palladium (Pd), germanium (Ge), and the like. . The bump electrode 160 is formed by a plating method, a printing method, or the like. Next, the semiconductor element 200 is overlaid on the insulating layer 140 and brought into contact with the bump electrodes 160 . Then, the semiconductor element 200 is mounted on the insulating layer 140 by performing reflow heat treatment.

Although the bump electrode 260 is not described above, the bump electrode 260 is formed using the same material and method as the bump electrode 160 . As described above, the wiring board 100 is manufactured.

(1-3. Application example of wiring board)
Next, an example in which the wiring board of the present embodiment is applied to an electric device will be described.

FIGS. 8A to 8C are diagrams for explaining electrical equipment. The wiring board 100 described above can be used, for example, in portable terminals (mobile phones, smartphones, notebook personal computers, game machines, etc.), information processing devices (desktop personal computers, servers, car navigation systems, etc.), household electric appliances (microwave ovens, Air conditioners, washing machines, refrigerators), automobiles, and various other electrical equipment. FIG. 8A shows a smartphone 4000. FIG. FIG. 8B shows a portable game machine 5000. FIG. FIG. 8C shows a notebook personal computer 6000 . 8A to 8C, the semiconductor element 200 of the wiring board 100 is used as, for example, an image sensor, and the wiring board 100 is provided together with the semiconductor element 200. FIG.

By using the wiring board 100 of the present embodiment, the wiring board 100-1, or the wiring board 100-2 described later in these electric devices, the insulating layer used for the wiring board is prevented from being degraded by light. . Thereby, good electrical connection between elements can be maintained for a long period of time. Therefore, it is possible to provide a highly reliable electrical device having light resistance.

Hereinafter, the properties of the insulating layer of the embodiment of the present disclosure will be described in more detail based on examples, but the present disclosure is not limited to these examples.

(3-1. Conditions for forming insulating layer in Example 1)
A composition for an organic insulating layer containing an acrylic resin and a carbazole-type oxime ester photopolymerization initiator was applied onto a smooth glass substrate. Next, the composition for an organic insulating layer was irradiated with light including a wide wavelength range of 300 nm or more and 450 nm or less to cure the composition, thereby forming an organic insulating layer having a thickness of 6 μm.

(3-2. Transmittance evaluation)
Transmittance evaluation is the method described in Japanese Industrial Standards (JIS) "Calculation of visible light transmittance and visible light reflectance" (http://kikakurui.com/r3/R3106-1998-02.html) Based on this, a UV-visible spectrophotometer was used for a measurement sample having an insulating layer formed under the conditions described above. At this time, the transmittance was measured at each point at intervals of 1 nm in the wavelength range of 200 nm or more and 800 nm or less. FIG. 9 is a transmittance spectrum in a wavelength range of 200 nm or more and 800 nm or less.

As shown in FIG. 9, in the case of Example 1, the transmittance at a wavelength of 365 nm is 80% or more, and the transmittance at a wavelength range of 380 nm or more and 780 nm or less is 90%. That is, by using the insulating layer of this embodiment, it is possible to provide a wiring substrate having light resistance and high reliability.

(Modification 1)
In the present embodiment, an example in which the through-electrode 120 is filled in the through-hole 115 is shown, but the present invention is not limited to this. FIG. 10 is a cross-sectional view of the wiring board 100-1. Wiring substrate 100 - 1 includes substrate 110 , through electrode 121 , insulating layer 140 , wiring 150 , bump electrode 160 , semiconductor element 200 , insulating layer 240 , wiring 250 and bump electrode 260 . As shown in FIG. 10 , the through electrode 121 may be formed only on the side wall portion of the through hole 115 without filling the through hole 115 . In this case, the through electrode 121 can be formed collectively in the wiring portions corresponding to the wiring 130 and the wiring 230 . The through electrode 121 can be formed by a semi-additive method. Also, a filler 122 may be provided inside the through electrode 121 . At this time, a material similar to that of the insulating layer 140 may be provided. As a result, the difference in thermal expansion coefficient between the insulating layer 140 and the filling material 122 can be reduced, so that the stress between the insulating layer 140 and the filling material 122 is relieved, and the electrical connection between the element and the wiring board is prevented. can be stabilized. Therefore, a highly reliable wiring board can be provided.

(Modification 2)
In this embodiment, an example in which one layer of the insulating layer 140 is provided on the substrate 110 is shown, but the present invention is not limited to this. FIG. 11 is a cross-sectional view of the wiring board 100-2. The wiring board 100-2 includes a substrate 110, a through electrode 120, a wiring 130, an insulating layer 140, a wiring 150, a bump electrode 160, a semiconductor element 200, a wiring 230, an insulating layer 240, a wiring 250, and a bump electrode 260, as well as wiring. 170 , insulating layer 180 and wiring 190 . An insulating layer 180 is provided on the insulating layer 140 . Insulating layer 180 preferably contains a material similar to that of insulating layer 140, specifically, a compound having an oxime ester structure, a carbazole group, or a phenylsulfide group together with an acrylic resin. At this time, the insulating layer 180 has the same light transmittance as the insulating layer 140. Specifically, the insulating layer 180 also has a transmittance of 80% or more at a wavelength of 365 nm and a light transmittance of 80% or more at a wavelength of 380 nm or more and 780 nm or less. Transmittance becomes 90% or more. As a result, deterioration of the insulating layers can be suppressed even when a plurality of insulating layers are provided. Thereby, it is possible to provide a wiring board having light resistance and high reliability.

In this embodiment, an example in which a glass substrate is used as the substrate is shown, but the present invention is not limited to this. The substrate 110 may be a semiconductor material such as silicon (Si), germanium (Ge), silicon germanium (SiGe), silicon carbide (SiC), gallium arsenide (GaAs), a glass substrate such as a sapphire substrate, or a silicon nitride (SiN) substrate. ) substrate, an aluminum nitride (AlN) substrate, a zirconia (ZrO ₂ ) substrate, an aluminum oxide (Al ₂ O ₃ ) substrate, or the like.

DESCRIPTION OF SYMBOLS 100... Wiring board, 110... Substrate, 115... Through hole, 120... Through electrode, 130... Wiring, 137... Light, 140... Insulating layer, 145... Opening 150 Wiring 160 Bump electrode 170 Wiring 180 Insulating layer 190 Wiring 200 Semiconductor element 230 Wiring 240 Insulating layer 250 Wiring 260 Bump electrode 4000 Smart phone 5000 Portable game machine 6000 Notebook personal computer

Claims (10)

a substrate having a first side and a second side opposite the first side;
an insulating layer provided on the first surface of the substrate;
a light-emitting or light-receiving semiconductor device provided on the insulating layer;
The insulating layer has an internal transmittance of 80% or more at a wavelength of 365 nm per 1 μm of thickness , and an internal transmittance of 90% or more in a wavelength region of 380 nm or more and 780 nm or less per 1 μm of thickness. A wiring board characterized by: 2. The wiring board according to claim 1, wherein the insulating layer is an organic insulating layer. The insulating layer contains a compound having an oxime ester structure,
The wiring board according to claim 2. The insulating layer contains a compound having a carbazole group or a phenylsulfide group,
The wiring board according to claim 2 or 3. further comprising a plurality of first wirings provided on the same plane on the first surface side of the substrate;
The insulating layer is provided between the plurality of first wirings,
5. The wiring board according to claim 1. a plurality of second wirings provided on the same plane on the second surface side of the substrate;
a through hole penetrating through the substrate;
a through electrode provided in the through hole,
One of the plurality of first wirings and one of the plurality of second wirings are electrically connected by the through electrodes,
The wiring board according to claim 5. 7. The wiring board according to claim 1, wherein the difference between the refractive index of said substrate and the refractive index of said insulating layer is 0.2 or less. 8. The wiring substrate according to claim 7, wherein said substrate is made of glass. forming wiring on the substrate,
applying a composition for an organic insulating layer containing a compound having an oxime ester structure on the substrate and the wiring;
Photocuring the composition for an organic insulating layer to form an insulating layer,
forming an opening on the wiring in the insulating layer;
connecting the wiring and a semiconductor element that emits light or receives light through the opening ;
The insulating layer has an internal transmittance of 80% or more at a wavelength of 365 nm per 1 μm of thickness, and an internal transmittance of 90% or more in a wavelength region of 380 nm or more and 780 nm or less per 1 μm of thickness.
A method for manufacturing a wiring board. The content of the compound having an oxime ester structure in the composition for an organic insulating layer is 5% by mass or less.
A method of manufacturing a wiring board according to claim 9 .

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