JP7741789B2 - Wiring board and method for manufacturing the same - Google Patents

Description

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

A wiring board is known in which electrode pads and conductor layers are arranged on both sides of a ceramic layer that functions as an insulating layer (see, for example, Patent Document 1). In the wiring board described in Patent Document 1, electrode pads are arranged on one side of the ceramic layer, and a conductor layer is arranged on the other side of the ceramic layer. The electrode pads and conductor layer are electrically connected via via conductors that penetrate the ceramic layer.

Japanese Patent Application Laid-Open No. 2020-113722

In the wiring board described in Patent Document 1, heat generated by the device is transferred to the conductor layer via the semi-lacquered layer and via conductors. Because the ceramic layer has a larger volume than the via conductors, the heat is primarily dissipated through the ceramic layer, which has lower thermal conductivity than the metal that forms the via conductors. Because the ceramic layer has low thermal conductivity, it is not possible to completely dissipate the heat generated by the device mounted on the electrode pad, and in some cases it is not possible to increase the output of the device to prevent it from being destroyed by heat.

The present invention has been made to solve at least some of the above-mentioned problems, and aims to improve the dissipation of heat transmitted through electrode pads.

The present invention has been made to solve at least part of the above-mentioned problems, and can be realized in the following form: A wiring board comprising: a first insulating substrate formed of a flat insulating material and having a first through hole penetrating in a thickness direction; and a second insulating substrate directly laminated on the first insulating substrate, the second insulating substrate also formed of a flat insulating material and having a second through hole penetrating in a thickness direction, wherein a flip-chip pad made of metal is provided inside the first through hole, and a solder mounting pad made of metal is provided inside the second through hole, at least a portion of the solder mounting pad is in contact with the flip-chip pad. The present invention can also be realized in the following form.

(1) According to one aspect of the present invention, a wiring board is provided. This wiring board comprises a first insulating substrate formed from a flat insulating material and having a first through-hole penetrating in the thickness direction; and a second insulating substrate laminated directly on the first insulating substrate, the second insulating substrate also formed from a flat insulating material and having a second through-hole penetrating in the thickness direction. A first metal pattern made of metal is provided inside the first through-hole, and a second metal pattern made of metal is provided inside the second through-hole, with at least a portion of the second metal pattern in contact with the first metal pattern.

With this configuration, the first metal pattern formed in the first through-hole of the first insulating substrate is in direct contact with the second metal pattern formed in the second through-hole of the second insulating substrate. As a result, heat generated in the first metal pattern is transferred directly to the second metal pattern, which has higher thermal conductivity than the insulating material. This improves the heat dissipation performance of the wiring board. As a result, the output of the device mounted on the first metal pattern or the second metal pattern can be increased.

(2) In the wiring board of the above embodiment, the first through hole may penetrate the first and second main surfaces of the first insulating substrate, and the second through hole may penetrate the third and fourth main surfaces of the second insulating substrate. The wiring board may have either a first extension portion formed in the first metal pattern, protruding from the first through hole in a planar view, and extending to the first and second main surfaces of the first insulating substrate, or a second extension portion formed in the second metal pattern, protruding from the second through hole in a planar view, and extending to the third and fourth main surfaces of the second insulating substrate.
According to this configuration, either a first extension portion formed on the first metal pattern or a second extension portion formed on the second metal pattern is formed. The first metal pattern, made of metal, protrudes from the first and second main surfaces, which are both surfaces of the first insulating substrate, and the area of the protruding portion is larger than the first through hole. Therefore, the protruding portion is caught in the first through hole, making it difficult for the first metal pattern to come off the first through hole. Similarly, the second metal pattern protrudes from the third and fourth main surfaces of the second insulating substrate, making it difficult for the second metal pattern to come off the second insulating substrate. In other words, by forming at least one of the first extension portion and the second extension portion, at least one of the first metal pattern and the second metal pattern does not come off the respective insulating substrate, thereby improving the strength of the wiring board.

The present invention can be realized in various forms, such as wiring boards, packages, electronic components, and systems including these, as well as methods for manufacturing wiring boards and systems including these.

1 is a schematic perspective view of a wiring board according to an embodiment of the present invention; FIG. FIG. 2 is an enlarged cross-sectional view of a flip chip pad. FIG. 2 is an enlarged cross-sectional view of a solder mounting pad. 3 is a flowchart of a method for manufacturing a wiring board according to the present embodiment. FIG. 2 is a schematic cross-sectional view of an alumina sheet during punching treatment. FIG. 2 is a schematic cross-sectional view of an alumina sheet before embedding flip chip pads. FIG. 2 is a schematic cross-sectional view of an alumina sheet after embedding flip chip pads. FIG. 1 is a schematic cross-sectional view of a tungsten sheet that has been pressed from both sides. 10 is a flowchart of a method for manufacturing a wiring board according to a comparative example.

1 and 2 are explanatory diagrams of a wiring board 100 according to an embodiment of the present invention. In the wiring board 100 of this embodiment, a flip-chip pad (first metal pattern) 30 embedded in the first ceramic substrate 10 is in direct contact with a solder mounting pad (second metal pattern) 40 embedded in the second ceramic substrate 20. As a result, heat generated from a device mounted on the flip-chip pad 30 is transferred directly to the highly thermally conductive solder mounting pad 40 without passing through the first ceramic substrate 10 and the second ceramic substrate 20. As a result, the heat dissipation performance of the wiring board 100 is improved, enabling the output of the device mounted on the flip-chip pad 30 to be increased.

Figure 1 shows a schematic perspective view of the wiring substrate 100. In Figure 1, the outer frames of the first ceramic substrate 10 and the second ceramic substrate 20 are shown with dashed lines, and the shapes of the embedded flip chip pads 30 and solder mounting pads 40 are visible. Figure 2 shows an exploded perspective view of the wiring substrate 100.

As shown in FIGS. 1 and 2 , a wiring board 100 of this embodiment includes a first ceramic substrate 10 and a second ceramic substrate 20. The first ceramic substrate 10 has a flat plate shape and is made of a ceramic material, alumina (Al ₂ O ₃ ). The first ceramic substrate 10 has through holes (first through holes) 11 and 12 formed therein, penetrating a front surface (first main surface) 13 and a back surface (second main surface) 14 opposite the front surface 13. The Cartesian coordinate system CS shown in FIGS. 1 and 2 is composed of an X-axis and a Y-axis parallel to two sides of the rectangular front surface 13 and back surface 14, and a Z-axis parallel to a direction perpendicular to the front surface 13 and back surface 14. The Cartesian coordinate system CS shown in FIGS. 1 and 2 corresponds to the Cartesian coordinate system CS shown in FIGS. 3 and subsequent figures.

As shown in FIG. 2, through hole 11 and through hole 12 each have a predetermined shape that penetrates in the Z-axis direction (thickness direction) with a constant cross-sectional area from front surface 13 to back surface 14. In this embodiment, through hole 11 and through hole 12 are formed as separate holes that are not connected to each other.

The flip chip pad 30 is formed from a metal such as W, Mo, Ag, or Cu. As shown in FIG. 1, the flip chip pad 30 is disposed inside the through holes 11 and 12 of the first ceramic substrate 10. As shown in FIG. 2, the flip chip pad 30 has a first pad 31 and a second pad 32 that are separate and unconnected. The first pad 31 is located within the through hole 11 of the first ceramic substrate 10 and has the same shape as the through hole 11. However, a portion of the first pad 31 protrudes from the through hole 11 in the thickness direction.

Figure 3 is an explanatory diagram of a first pad 31 protruding from a through hole 11. Figure 3 shows an enlarged schematic cross-section of a portion of the first ceramic substrate 10 and the first pad 31 in the ZX plane. As shown in Figure 3, the first pad 31 includes a filling portion 31A located within the through hole 11 and extension portions (first extension portions) 31B and 31C that extend from the through hole 11 in the thickness direction. The extension portion 31B extends from the through hole 11 to the front surface 13 of the first ceramic substrate 10 along the XY plane in a plan view from the thickness direction. Similarly, the extension portion 31C protrudes from the through hole 11 to the rear surface 14 of the first ceramic substrate 10 along the XY plane in a plan view. In other words, the first pad 31 protrudes from the through hole 11 to the front surface 13 and rear surface 14 of the first ceramic substrate 10. In this embodiment, a plan view refers to a view of the flat ceramic substrates 10 and 20 along the thickness direction; if the view direction is different, expressions such as a side view are used.

As shown in Figures 1 and 2, the second pad 32 has the same shape as the through hole 12 within the through hole 12 of the first ceramic substrate 10. However, like the first pad 31 shown in Figure 3, a portion of the second pad 32 protrudes from the through hole 12 and extends to both the front surface 13 and the back surface 14 of the first ceramic substrate 10.

The second ceramic substrate 20 has a flat plate shape and is made of alumina, a ceramic material. Furthermore, as shown in FIG. 2, the second ceramic substrate 20 has through holes (second through holes) 21, 22 formed therein, penetrating a front surface (third main surface) 23 and a back surface (fourth main surface) 24 opposite the front surface 23. As shown in FIG. 2, each of the through holes 21 and 22 has a predetermined shape that penetrates from the front surface 23 to the back surface 24 in the Z-axis direction (thickness direction) with a constant cross-sectional area. In this embodiment, the through holes 21 and 22 are formed so as not to be connected.

The solder mounting pad 40 is formed from a metal such as W, Mo, Ag, or Cu. As shown in FIG. 1, the solder mounting pad 40 is disposed inside the through holes 21 and 22 of the second ceramic substrate 20. As shown in FIG. 2, the solder mounting pad 40 has a first pad 41 and a second pad 42 that are separate and unconnected. The first pad 41 has the same shape as the through hole 21 within the through hole 21 of the second ceramic substrate 20.

Figure 4 is an explanatory diagram of a first pad 41 protruding from a through hole 21. Similar to Figure 3, Figure 4 shows an enlarged schematic cross-sectional view of a portion of the second ceramic substrate 20 and first pad 41 in the ZX plane. As shown in Figure 4, the first pad 41 includes a filling portion 41A located within the through hole 21 and extension portions (second extension portions) 41B and 41C that extend from the through hole 21 in the thickness direction. The extension portion 41B extends from the through hole 21 to the outside along the XY plane in a plan view, and onto the front surface 23 of the first ceramic substrate 20. Similarly, the extension portion 41C protrudes from the through hole 21 to the rear surface 24 of the second ceramic substrate 20 along the XY plane in a plan view. In other words, the first pad 41 protrudes from the through hole 21 to the outside and extends onto both the front surface 23 and the rear surface 24 of the first ceramic substrate 20.

An insulating layer 50, shown as the hatched area in Figure 2, is formed on part of the surface 43 of the first pad 41 of the solder mounting pad 40. The insulating layer 50 is made of an insulator.

The second pad 42 of the solder mounting pad 40 is located within the through hole 22 of the second ceramic substrate 20 and has the same shape as the through hole 22. However, a portion of the second pad 42 protrudes from the through hole 22 and extends to both the front surface 23 and the back surface 24 of the second ceramic substrate 20, similar to the first pad 41 of the second ceramic substrate 20 shown in FIG. 4 .

When a first ceramic substrate 10 having flip chip pads 30 provided in through holes 11 and 12 and a second ceramic substrate 20 having solder mounting pads 40 provided in through holes 21 and 22 are stacked as shown in FIG. 1, the back surfaces 33 and 34 of the flip chip pads 30 come into contact with the majority of the surfaces 43 and 44 of the solder mounting pads 40. Note that in the portion of the surface 43 of the first pad 41 of the solder mounting pad 40 where the insulating layer 50 is formed, the flip chip pads 30 and the solder mounting pad 40 do not come into direct contact due to the insulating layer 50 interposed therebetween.

As described above, in the wiring board 100 of this embodiment, the first ceramic substrate 10 has a flat, ceramic-plate shape. As shown in FIG. 1, the flip-chip pads 30 are disposed inside the through-holes 11 and 12 of the first ceramic substrate 10. The second ceramic substrate 20 has a flat, ceramic-plate shape. As shown in FIG. 1, the solder mounting pads 40 are disposed inside the through-holes 21 and 22 of the second ceramic substrate 20. In the wiring board 100 of this embodiment, the flip-chip pads 30 disposed inside the through-holes 11 and 12 of the first ceramic substrate 10 are in direct contact with the solder mounting pads 40 disposed inside the through-holes 21 and 22 of the second ceramic substrate 20. Therefore, heat generated in the flip-chip pads 30 is directly transferred to the solder mounting pads 40, which have higher thermal conductivity than the ceramic substrates 10 and 20. This improves the heat dissipation of the wiring board 100. As a result, the output of the device mounted on the flip-chip pads 30 can be increased. In particular, LEDs (light-emitting diodes), which generate a lot of heat as their output increases, can be used as devices to increase the output of the LEDs.

Furthermore, as shown in FIG. 3, in the first pad 31 of the flip chip pad 30 of this embodiment, the extensions 31B and 31C protrude outward from the through hole 11 and extend onto the front surface 13 and back surface 14 of the first ceramic substrate 10, respectively. Similarly, the extensions 41B and 41C (FIG. 4) of the first pad 41 of the solder mounting pad 40 protrude outward from the through hole 22 and extend onto the front surface 23 and back surface 24 of the second ceramic substrate 20, respectively. That is, in this embodiment, the first pad 31 and the second pad 32 of the flip chip pad 30 protrude outward from the front surface 13 and back surface 14, which are both surfaces of the first ceramic substrate 10, and the area of each of the protruding portions is larger than the through holes 11 and 12. Therefore, the protruding portions are caught in the through holes 11 and 12, making it difficult for the flip chip pad 30 to come off the through holes 11 and 12. Similarly, the solder mounting pads 40 protrude from the front surface 23 and back surface 24 of the second ceramic substrate 20, and therefore are less likely to come off the second ceramic substrate 20. In other words, the flip chip pads 30 and the solder mounting pads 40 do not come off their respective ceramic substrates 10, 20, improving the strength of the wiring substrate 100.

Figure 5 is a flowchart of a method for manufacturing the wiring board 100 of this embodiment. In the manufacturing flow for the wiring board 100 shown in Figure 5, an alumina sheet that serves as the base of the first ceramic substrate 10 is attached to a predetermined sheet frame (Step S1). The thickness of the alumina sheet in this embodiment is approximately 200 nm. Through holes 11, 12 and through holes (TH) of predetermined shapes are formed in the alumina sheet attached to the sheet frame by punching (Step S2). Flip chip pads 30 are embedded in the formed through holes 11, 12 (Step S3). Note that the term "through hole" used in this specification refers to a through hole for an electronic component.

Figures 6 through 9 are explanatory diagrams illustrating the formation of through holes 11 and 12 and the embedding of flip chip pads 30. Figures 6 through 9 show schematic cross-sectional views of the wiring substrate 100 during its manufacture. Figure 6 shows a cross-section during the punching process of step S2 in Figure 5. As shown in Figure 6, the alumina sheet SA attached to the sheet frame FR is fixed directly or indirectly to the middle die F2 and lower die F3. The alumina sheet SA has through holes 11 and 12 and through-holes punched into a predetermined shape by the upper die F1, which is a punch.

As shown in Figures 7 and 8, once the through holes 11 and 12 and through-holes are formed in the alumina sheet SA, the upper die F1 punches out a reel-shaped tungsten sheet SC into the same shape as the through holes 11 and 12. In this embodiment, the thickness of the tungsten sheet SC is approximately 0.1 mm thicker than the thickness of the alumina sheet SA. As shown in Figure 8, the punched tungsten sheet SC1 is embedded in the through holes 11 and 12 of the alumina sheet SA. In this embodiment, the tungsten sheet SC1 is embedded to about half the depth of the through holes 11 and 12, and then, as shown in Figure 9, is pressed from both sides in the thickness direction by pressing plates F4 and F5. Because the thickness of the tungsten sheet SC is greater than the thickness of the alumina sheet SA, portions of the tungsten sheet SC1 protrude from the through holes 11 and 12 and extend to both sides of the alumina sheet SA in a rivet-like manner.

After step S3 in FIG. 5 is completed, the remaining through-holes in the alumina sheet SA that are not filled with the tungsten sheet SC1 are screen-printed (thread-hole printing) (step S4). Next, an insulating paste is printed on the surface of a portion of the filled tungsten sheet SC1 to form an insulating layer 50 (step S5). In this embodiment, the insulating paste is not printed on the flip-chip pads 30, but is printed on portions of the solder mounting pads 40. The punching process (step S2) described above corresponds to the first through-hole formation process and the second through-hole formation process. The pad filling process (step S3) corresponds to the first filling process and the second filling process.

The above steps S1 to S5 are the same as those used to manufacture the second ceramic substrate 20 and solder mounting pad 40. This is followed by a lamination process in which the pre-fired first ceramic substrate 10 and the pre-fired second ceramic substrate 20 are stacked together (step S6). In this lamination process, two tungsten sheets are stacked so that the tungsten sheet SC1 embedded in the alumina sheet SA that forms the first ceramic substrate 10 comes into contact with the tungsten sheet embedded in the alumina sheet that forms the second ceramic substrate 20.

After lamination, the laminate is cut to the shape of the completed wiring board 100 (step S7). Next, the laminate is baked at a predetermined temperature for a predetermined time (step S8). Baking removes the resin components from the laminate, completing the wiring board 100.

Figure 10 is a flowchart of a method for manufacturing a wiring board according to a comparative example. In the manufacturing flow for a wiring board according to the comparative example shown in Figure 10, step S5 is not included in the manufacturing flow for the above embodiment shown in Figure 5, and steps S2x, S3x, and S4 are replaced by steps S2x, S3x, and S4. Therefore, in the manufacturing flow for the comparative example, only the processes that differ from those in the manufacturing flow for the above embodiment will be described, and the same processes will not be described again.

As shown in FIG. 10, after attaching an alumina sheet to a sheet frame (step S1), vias and through-holes of a predetermined shape are formed by punching (step S2x). In the comparative example, vias that penetrate the ceramic substrate are formed instead of the through holes 11 and 12 of the embodiment. The formed vias are then filled with metal paste (step S3x). In the metal paste filling process, the metal sheet used for filling is placed on the alumina sheet with zero gap and pressurized. After filling, the metal sheet is peeled off from the alumina sheet. Note that the fired metal paste functions as a via conductor in the wiring board.

Next, pattern printing and through-hole printing are performed. In the comparative example, pattern printing, which prints a predetermined conductor pattern, is performed simultaneously with the through-hole printing of the embodiment (step S4 in Figure 5). In the comparative example, the conductor pattern is formed by printing or plating only on the necessary parts of the surface layer of the alumina sheet, so the printing of insulating paste of the embodiment (step S5 in Figure 5) is not performed.

As described above, the manufacturing method for the wiring board 100 of this embodiment, compared to the manufacturing method of the comparative example, provides direct contact between the metal flip-chip pads 30 and the metal solder mounting pads 40 of the manufactured wiring board 100, thereby improving the heat dissipation of the wiring board 100. Furthermore, in this embodiment, the flip-chip pads 30 are embedded in the first ceramic substrate 10, eliminating surface irregularities on the flip-chip pads 30 and improving flatness. This allows for stable mounting to the flip-chip pads 30, even in electronic device assemblies with a narrow window (bonding area) for mounting conditions on the flip-chip pads 30, such as Au-Au bonding. Furthermore, unlike the comparative example, the manufacturing method of this embodiment does not require vias, thereby reducing the multiple sheet scraps generated by punching for via formation (step S2x in Figure 10). Furthermore, the alumina sheet deformation caused by pressure application and metal sheet peeling during the metal paste filling process (step S3x in Figure 10) performed in the comparative example does not occur in the wiring board 100 of this embodiment.

<Modification of this embodiment>
The present invention is not limited to the above-described embodiment, and can be embodied in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

<Modification 1>
The example of wiring substrate 100 and the manufacturing method of wiring substrate 100 in the above embodiment are merely examples and can be modified. The shapes of through holes 11, 12 formed in first ceramic substrate 10 and through holes 21, 22 formed in second ceramic substrate 20 may be determined according to the design of wiring substrate 100 or an electronic component including wiring substrate 100. The area where insulating layer 50 is formed may also be determined appropriately according to the design.

The first ceramic substrate 10 and the second ceramic substrate 20 may be formed from an insulating material other than alumina. The flip chip pad 30 and the solder mounting pad 40 may be any metal pattern formed from a metal, such as a heat sink. The flip chip pad 30 and the solder mounting pad 40 may be formed from metals such as Al, Au, Pt, Ti, Cu, Pd, Rh, Ni, W, Mo, Cr, Ag, etc., or alloys of these metals.

While the wiring board 100 of this embodiment includes two stacked substrates, the first ceramic substrate 10 and the second ceramic substrate 20, three or more stacked substrates may be used. While the flip chip pad 30 and the solder mounting pad 40 each consist of two unconnected pads, they may instead consist of a single electrode pad or three or more electrode pads. For example, multiple electrode pads or metal patterns may be embedded in a single through-hole 11 formed in the first ceramic substrate 10. At least one of the flip chip pad 30 and the solder mounting pad 40 may not have a rivet-like shape that protrudes from the surface of the ceramic substrate, but may instead be completely contained within the through-hole. That is, the flip chip pad 30 may not have extensions 31B and 31C (Figure 3), and the solder mounting pad 40 may not have extensions 41B and 41C (Figure 4). In this case, the thickness of the tungsten sheet SC before firing may be the same as the thickness of the alumina sheet SA. Unlike the above embodiment, the thickness of the alumina sheet SA and tungsten sheet SC may be less than 200 nm or greater than 200 nm.

The manufacturing method for the wiring substrate 100 shown in FIG. 5 is one example and can be modified as long as it includes the punching process (step S2), the pad embedding process (step S3), and the lamination process (step S6). For example, the insulating paste printing process (step S5) may not be performed, and the insulating layer 50 may not be formed on the wiring substrate 100.

This aspect has been described above based on embodiments and variations, but the above-described embodiments are intended to facilitate understanding of this aspect and are not intended to limit this aspect. This aspect may be modified or improved without departing from its spirit or the scope of the claims, and equivalents are included in this aspect. Furthermore, if a technical feature is not described as essential in this specification, it may be deleted as appropriate.

The present invention can also be realized in the following forms.
[Application Example 1]
A wiring board,
a first insulating substrate formed of a flat insulating material and having a first through-hole penetrating in a thickness direction;
a second insulating substrate directly laminated on the first insulating substrate, the second insulating substrate being made of a flat insulating material and having a second through-hole penetrating in a thickness direction;
Equipped with
a first metal pattern formed of a metal is provided inside the first through hole;
a second metal pattern formed of a metal is provided inside the second through hole;
A wiring board, wherein at least a portion of the second metal pattern is in contact with the first metal pattern.
[Application Example 2]
The wiring board according to Application Example 1,
the first through-hole penetrates through a first main surface and a second main surface of the first insulating substrate;
the second through hole penetrates through a third main surface and a fourth main surface of the second insulating substrate,
a first extension portion formed on the first metal pattern, protruding from the first through hole in a plan view and extending to each of the first main surface and the second main surface of the first insulating substrate; or
A wiring board characterized by having either a second extension portion formed on the second metal pattern, protruding out of the second through hole in a planar view, and extending to each of the third main surface and the fourth main surface of the second insulating substrate.
[Application Example 3]
A method for manufacturing a wiring substrate,
a first through-hole forming step of forming a first through-hole penetrating a first insulating substrate formed of a flat insulating material in a thickness direction;
a first embedding step of embedding a first metal pattern made of metal into the first through hole;
a second through-hole forming step of forming a second through-hole penetrating a second insulating substrate formed of a flat insulating material in a thickness direction;
a second embedding step of embedding a second metal pattern made of metal into the second through hole;
a lamination step of laminating the first insulating substrate and the second insulating substrate so that at least a portion of the second metal pattern is in contact with the first metal pattern;
A method for manufacturing a wiring board, comprising:

10...First ceramic substrate (first insulating substrate)
11, 12...through holes (first through holes)
13... Surface (first main surface) of first ceramic substrate
14... Back surface (second main surface) of first ceramic substrate
20...Second ceramic substrate (second insulating substrate)
21, 22...through holes (second through holes)
23: Surface of second ceramic substrate (third main surface)
24: Back surface (fourth main surface) of second ceramic substrate
30...flip chip pad (first metal pattern)
31...first pad of flip chip pad 31A...filled portion 31B...extension portion (first extension portion)
31C...extension portion (first extension portion)
32... Second pad of flip chip pad 33... Back surface of flip chip pad 40... Solder mounting pad (second metal pattern)
41...first pad of solder mounting pad 41A...filled portion 41B...extension portion (second extension portion)
41C...extension portion (second extension portion)
42... Second pad of solder mounting pad 43... Surface of solder mounting pad 50... Insulating layer 100... Wiring board CS... Cartesian coordinate system F1... Upper mold F2... Middle mold F3... Lower mold F4, F5... Surface pressing plate FR... Sheet frame SA... Alumina sheet SC, SC1... Tungsten sheet

Claims (4)

A wiring board,
a first insulating substrate formed of a flat insulating material and having a first through-hole penetrating in a thickness direction;
a second insulating substrate directly laminated on the first insulating substrate, the second insulating substrate being made of a flat insulating material and having a second through-hole penetrating in a thickness direction;
Equipped with
a flip chip pad made of metal is provided inside the first through hole;
a solder mounting pad made of metal is provided inside the second through hole,
A wiring board, characterized in that at least a portion of the solder mounting pad is in contact with the flip chip pad . 2. The wiring board according to claim 1,
the first through-hole penetrates through a first main surface and a second main surface of the first insulating substrate;
the second through hole penetrates through a third main surface and a fourth main surface of the second insulating substrate,
a first extension portion formed on the flip chip pad , protruding from the first through hole in a plan view and extending to the first main surface and the second main surface of the first insulating substrate;
or
A wiring board characterized by having a second extension portion formed on the solder mounting pad , protruding out of the second through hole in a planar view, and extending to each of the third main surface and the fourth main surface of the second insulating substrate. 2. The wiring board according to claim 1,
the flip chip pad has a constant cross-sectional area along a lamination direction of the first insulating substrate and the second insulating substrate,
The wiring board is characterized in that the solder mounting pad has a constant cross-sectional area along the stacking direction. A method for manufacturing a wiring substrate,
a first through-hole forming step of forming a first through-hole penetrating a first insulating substrate formed of a flat insulating material in a thickness direction;
a first embedding step of embedding a flip chip pad made of metal inside the first through hole;
a second through-hole forming step of forming a second through-hole penetrating a second insulating substrate formed of a flat insulating material in a thickness direction;
a second embedding step of embedding a solder mounting pad made of metal inside the second through hole;
a lamination step of laminating the first insulating substrate and the second insulating substrate so that at least a portion of the solder mounting pad contacts the flip chip pad ;
A method for manufacturing a wiring board, comprising: