JP3953900B2 - Multilayer resin wiring board and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a laminated resin wiring board and a method for manufacturing the same, and more particularly to a laminated resin wiring board characterized by the structure of a metal plate used as a core material or a base material and a method for manufacturing the same.
[0002]
[Prior art]
In recent years, with the miniaturization of electrical equipment, electronic equipment, etc., miniaturization and high density are also required for wiring boards mounted on these equipments. In order to meet such market demand, multilayer circuit board technology has been studied. As a multilayering method, a so-called build-up method in which insulating layers and wiring layers are alternately laminated and integrated with a core material or a base material is generally employed. As this type of conventional wiring board, a metal core board or a metal base board using a metal plate is known for improving heat dissipation and reducing the thermal expansion coefficient of the whole board (Japanese Patent Laid-Open No. 2000-133913). reference).
[0003]
By the way, among the wiring layers of the metal core substrate and the metal base substrate, particularly those that are closest to the metal plate need to ensure a predetermined insulation reliability with the metal plate. And the insulation reliability about this part will depend on the physical characteristic, thickness, etc. of resin used as an insulating layer fundamentally.
[0004]
[Problems to be solved by the invention]
In recent metal core substrates and metal base substrates, there is a strong demand for lightness and reduction in size. Therefore, it is required to reduce the thickness of the insulating layer as much as possible in order to suppress the dimension in the substrate thickness direction. Such a thinning of the insulating layer is also required from the viewpoint of improving the hole workability when a via hole is formed in the insulating layer.
[0005]
However, when the resin insulation layer is further thinned, it is very difficult to ensure the insulation reliability between the wiring layer and the metal plate. In particular, a conductor pattern that is required to have higher insulation reliability than a normal conductor pattern (referred to as “first conductor pattern” for convenience) between the metal plate and the metal plate (referred to as “second conductor pattern” for convenience). ), This problem becomes more prominent.
[0006]
That is, if the thickness of the insulating layer is set to the insulating thickness required for the first conductor pattern, the insulating thickness is insufficient for the second conductor pattern that requires higher insulation reliability than that. End up. Therefore, at present, in order to ensure the insulation reliability of both, the thickness of the insulating layer has to be set to the insulation thickness required for the second conductor pattern. Therefore, the insulating layer becomes thick to some extent, and the dimension in the substrate thickness direction cannot be sufficiently suppressed.
[0007]
SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a laminated resin wiring board excellent in insulation reliability between the wiring layer and the metal plate while suppressing the dimension in the substrate thickness direction, and its It is to provide a manufacturing method.
[0008]
[Means, actions and effects for solving the problems]
Solution means for solving the above-described problems include a metal plate having a first main surface and a second main surface, and a wiring located on at least one of the first main surface and the second main surface. And a resin insulating layer interposed between the metal plate and the wiring layer, and the wiring layer includes a first conductor pattern required to have a predetermined insulation reliability between the metal plate and the metal layer. And a second conductor pattern that is required to have a higher insulation reliability than the first conductor pattern between the metal plate and a portion facing the second conductor pattern on the metal plate. The gist of the present invention is a laminated resin wiring board provided with holes.
[0009]
Therefore, according to the above invention, even if there is a second conductor pattern that requires higher insulation reliability than the first conductor pattern, the metal plate is provided with a hole at a location facing it. . And about the location in which the hole part was provided, the distance from the 2nd conductor pattern to the surface of a metal plate becomes large. Therefore, even when the thickness of the insulating layer is set to the insulating thickness required for the first conductor pattern, not only the insulation reliability between the first conductor pattern and the metal plate but also the second conductor Insulation reliability between the pattern and the metal plate is also ensured. In addition, according to the present invention, the thickness of the insulating layer may be set to an insulating thickness required for the first conductor pattern, so that the dimension in the substrate thickness direction can be sufficiently suppressed.
[0010]
The metal plate is appropriately selected in consideration of conductivity, cost, and ease of drilling when drilling. Examples of suitable metal plates include copper plates, copper alloy plates, and plate materials made of simple metals or alloys other than copper. Examples of the copper alloy include aluminum bronze (Cu—Al series), phosphor bronze (Cu—P series), brass (Cu—Zn series), cupronickel (Cu—Ni series), and the like. Examples of simple metals other than copper include aluminum, iron, chromium, nickel, molybdenum and the like. Examples of alloys other than copper include stainless steel (iron alloy such as Fe—Cr and Fe—Cr—Ni), amber (Fe—Ni alloy, 36% Ni), so-called 42 alloy (Fe—Ni alloy, 42 % Ni), so-called 50 alloy (Fe—Ni alloy, 50% Ni), nickel alloy (Ni—P, Ni—B, Ni—Cu—P), cobalt alloy (Co—P, Co—) B series, Co-Ni-P series), tin alloys (Sn-Pb series, Sn-Pb-Pd series) and the like.
[0011]
Among these, in particular, a plate material made of an Fe—Ni alloy such as amber, 42 alloy, or 50 alloy is preferably used as the metal plate. That is, since the Fe—Ni-based alloy has a property that its thermal expansion coefficient is smaller than that of copper, the thermal expansion of the entire substrate can be reduced by using it as a metal plate for a laminated resin wiring board. Because. In addition, Fe-Ni alloy is suitable for high added value because it is suitable for high added value because it is suitable for high added value though it is inferior to copper and has suitable conductivity. That's why. Furthermore, although Fe—Ni-based alloys are suitable for copper, although they are inferior to copper, high heat dissipation can be achieved by using them as metal plates for laminated resin wiring boards. .
[0012]
In addition, the thickness of the metal plate is not particularly limited, but to be strong, it is preferably 150 μm or more, more preferably 150 μm to 500 μm, and particularly preferably 150 μm to 300 μm. The reason for this is that if the thickness of the metal plate is less than 150 μm, the rigidity of the metal plate itself is reduced, so that wrinkles and scratches are likely to occur during the manufacturing process, resulting in a decrease in handleability and a decrease in yield. Because it leads to. On the other hand, if the thickness of the metal plate is 500 μm, there is no problem with respect to rigidity, but the laminated resin wiring board is not only thickened, but hole processing becomes difficult. In addition, when thickness is 150 micrometers or more as mentioned above, it is good to use a rolled metal material from viewpoints, such as cost property and productivity.
[0013]
The wiring layer may be located on both sides of the first main surface and the second main surface of the metal plate, and may be located only on the first main surface side or only on the second main surface side. Such a metal material for forming the wiring layer and a method for forming the wiring layer can be appropriately selected in consideration of conductivity, adhesion to the resin insulating layer, and the like. Examples of the metal material for forming the wiring layer include copper, copper alloy, nickel, nickel alloy, tin, tin alloy and the like. Such a wiring layer can be formed by a known method such as a subtractive method, a semi-additive method, or a full additive method. Specifically, for example, techniques such as etching of copper foil, electroless copper plating or electrolytic copper plating, electroless nickel plating or electrolytic nickel plating can be used. It is also possible to form a wiring layer by etching after forming a metal layer by a technique such as sputtering or CVD, or to form a wiring layer by printing a conductive paste or the like.
[0014]
The resin insulating layer interposed between the metal plate and the wiring layer can be appropriately selected in consideration of insulation, heat resistance, moisture resistance, and the like. Preferable examples of the resin material forming the resin insulating layer include EP resin (epoxy resin), PI resin (polyimide resin), BT resin (bismaleimide-triazine resin), PPE resin (polyphenylene ether resin) and the like. In addition, composite materials of these resins and organic fibers such as glass fibers (glass woven fabrics and glass nonwoven fabrics) and polyamide fibers, or three-dimensional network fluorine-based resin base materials such as continuous porous PTFE, epoxy resins, etc. A resin-resin composite material impregnated with a thermosetting resin may be used.
[0015]
Further, one or more resin insulation layers may be formed on the surface of the resin insulation layer formed on the main surface of the metal plate, and a wiring layer is formed on each resin insulation layer. It may be. In other words, the above laminated resin wiring board may be provided with only a resin insulating layer interposed between the metal plate and the wiring layer, or between the metal plate and the wiring layer and between different wiring layers. It may be provided with a plurality of resin insulation layers intervening.
[0016]
The laminated resin wiring board may be provided with a via-hole conductor (that is, a first via-hole conductor) that is formed in a resin insulating layer and connects and conducts between the wiring layer and the metal plate. This is because the presence of such a via-hole conductor allows the metal plate to function as a ground layer or a power supply layer. The first via-hole conductor is not limited to the one that conducts connection between the wiring layer located on the innermost layer and the metal plate, but connects between the wiring layer located on the outer layer side and the metal plate. It may be conductive.
[0017]
When the wiring layer and the resin insulating layer are present on both sides of the first main surface and the second main surface of the metal plate, the metal plate is formed with a metal plate through hole that communicates the first main surface and the second main surface. In addition, it is preferable that the inside be filled with a resin filler.
[0018]
Here, the resin filler can be appropriately selected in consideration of insulation, heat resistance, moisture resistance, and the like. Preferable examples of the resin material forming the resin filler include EP resin, PI resin, BT resin, PPE resin, and the like. That is, as long as it can be used as the resin material for forming the resin insulating layer, it can be used without any problem as the resin material for forming the resin filler. In addition, it is preferable from a viewpoint of cost efficiency or productivity to use what was used as the resin material for resin insulation layer as it is as a resin material for resin filler formation.
[0019]
Further, the laminated resin wiring board has a second via-hole conductor (that is, a metal that connects and connects the wiring layer on the first main surface side and the wiring layer on the second main surface side while maintaining insulation with the metal plate. (Plate insulating via-hole conductor), which may be formed by forming a via conductor in a via-hole forming hole penetrating the resin filler. In this case, the via hole forming hole can be formed by, for example, photoetching or drilling.
[0020]
The above-mentioned laminated resin wiring board connects and continually connects the wiring layers on both main surfaces while maintaining a connection conduction state with another via hole conductor different from the first and second via hole conductors, for example, a metal plate. A via hole conductor (that is, a metal plate conduction via hole conductor) or the like may be provided.
[0021]
Here, the method for forming the metal plate through-hole in the metal plate is not particularly limited, and various conventionally known hole-piercing methods can be employed. Examples of such methods include etching, laser processing, punching, and the like, but it is desirable to employ etching (especially double-sided simultaneous etching) when the metal plate is thick. Furthermore, it is desirable to employ photo-etching. In this case, it is possible to increase the positional accuracy of the metal plate through-hole formed, and to improve the yield.
[0022]
The “hole” provided in the metal plate refers to a concave structure that can substantially increase the distance from the second conductor pattern to the surface of the metal plate. The hole may or may not penetrate, but is preferably a non-through hole.
[0023]
The reason for this is that the configuration in which the non-penetrating hole is provided is less likely to be accompanied by a decrease in strength of the metal plate and less likely to be accompanied by a decrease in heat dissipation due to a decrease in volume of the metal plate. Further, since the non-through hole portion has a high degree of freedom in layout, it is advantageous in designing when the second conductor pattern is present on both main surface sides.
[0024]
The non-penetrating hole is preferably a groove formed substantially in parallel along the direction in which the second conductor pattern extends.
[0025]
This is because the distance from the surface of the metal plate can be increased over the entire extending direction of the second conductor pattern, and sufficient insulation reliability can be ensured between the metal plate and the second conductor pattern.
[0026]
When the hole is a groove, it is desirable that the width of the groove is set to be larger than the line width of the second conductor pattern. It is preferable to set 5 times to 10 times, particularly 1.5 times to 3 times. The reason is that if the width of the groove is the same as or smaller than the line width of the second conductor pattern, the distance from the metal plate is reduced at both edges of the second conductor pattern, and sufficient insulation reliability is achieved. This is because it is difficult to ensure the sex. Further, if the width of the groove is less than 1.5 times the line width of the second conductor pattern, it may be difficult to ensure sufficient insulation reliability depending on the dimensional tolerance of the second conductor pattern. . Conversely, the formation of a groove having a width exceeding 10 times the line width of the second conductor pattern may be difficult due to the space in the metal plate.
[0027]
The depth of the non-penetrating hole is preferably less than half of the thickness of the metal plate, specifically 1/100 to 1/3, particularly 1/10 to the thickness of the metal plate. It is good to set to 1/3. The reason is that if the hole is too shallow, the distance from the second conductor pattern to the surface of the metal plate cannot be made sufficiently large. On the other hand, if the hole is too deep, the strength and heat dissipation of the metal plate may be lowered in some cases. When forming non-through holes on both main surfaces of the metal plate, the depth may be set the same on the first main surface side and the second main surface side, or set differently. May be. However, it is generally more advantageous in terms of the process to form holes having the same depth on both sides.
[0028]
When forming non-penetrating holes on both main surfaces of the metal plate, non-penetrating holes (grooves) provided on the first main surface side and non-penetrating holes provided on the second main surface side It is desirable to dispose these in a state of being shifted in the substrate surface direction so that they do not overlap with the (groove portion) when viewed from the first main surface side. The reason is to prevent a reduction in the strength of the metal plate due to the occurrence of overlapping and thin portions.
[0029]
The hole is preferably filled with an insulating material, and more specifically, a resin for forming an insulating layer is preferably buried. The reason is that if a hole is provided in the metal plate and nothing is buried there (that is, there is a void), the adhesion between the metal plate and the resin insulating layer is likely to decrease, and reliability is improved. This is because the achievement of the objective is hindered.
[0030]
Another solution includes a step of forming a non-penetrating hole by a half-etching method at a predetermined location in a metal plate having a first main surface and a second main surface, and the metal in which the hole is formed. A predetermined insulation reliability is required between the step of forming a resin insulating layer on at least one of the first main surface and the second main surface of the plate and the metal plate. And forming a wiring layer on the resin insulating layer having a second conductive pattern that requires higher insulation reliability than the first conductive pattern between the conductive pattern and the metal plate, In that case, the gist is a method for manufacturing a laminated resin wiring board, including a step of arranging the second conductor pattern corresponding to the hole.
[0031]
Therefore, according to the said invention, a non-through-hole is comparatively easily formed by partially eroding a metal plate by a half etching method. Thereafter, by forming a resin insulating layer on the metal plate in which the hole is formed, the hole is filled with the resin material for forming the insulating layer. If the second conductor pattern is formed as described above, the second conductor pattern is in a position just corresponding to the hole, and the distance from the second conductor pattern to the surface of the metal plate is increased. Therefore, according to this manufacturing method, the above excellent laminated resin wiring substrate can be obtained relatively easily. Here, the half-etching method refers to a method of stopping the etching hole halfway without completely penetrating the etching hole when the substrate is eroded from one side surface by the etchant. When such a half-etching method is used, for example, the formation of a metal plate through hole and the formation of a non-through hole can be performed simultaneously, and a reduction in productivity and cost can be avoided.
[0032]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a laminated resin wiring board (so-called metal core board) according to an embodiment of the present invention will be described in detail with reference to FIGS.
[0033]
FIG. 1 schematically shows the laminated resin wiring board 11 of the present embodiment. The laminated resin wiring board 11 includes a metal plate (hereinafter referred to as “rolled amber plate 12”) made of amber, which is a kind of Fe—Ni-based rolled alloy, as a core material. In FIG. 1, buildup layers are formed on the upper surface (that is, the first main surface) 13 and the lower surface (that is, the second main surface) 14 of the rolled amber plate 12.
[0034]
The thickness of the rolled amber plate 12 is set to 0.25 mm, and a large number of 0.30 mmφ metal plate through holes 15 that allow the upper surface 13 and the lower surface 14 to communicate with each other are pierced at predetermined positions.
[0035]
The buildup layer on the upper surface 13 side has a structure in which the resin insulating layers 21 and 41 and the wiring layers 31 are alternately stacked. The buildup layer on the lower surface 14 side has a structure in which the resin insulating layers 22 and 42 and the wiring layers 32 are alternately stacked. That is, in this embodiment, the number of wiring layers 31 and 32 is equal on both sides of the laminated resin wiring board 11. The wiring layers 31 and 32 have a first insulation pattern 37 that requires a predetermined insulation reliability between the rolled amber plate 12 and the first conductive pattern 37 between the rolled amber plate 12. The second conductor pattern 38 is required to have higher insulation reliability. In the present embodiment, the second conductor pattern 38 is present on each of the upper surface 13 side and the lower surface 14 side of the rolled amber plate 12.
[0036]
On the upper surface 13 of the rolled amber plate 12, a groove portion 18, which is one mode of a non-through hole, is provided at a location facing the second conductor pattern 38. On the other hand, in the lower surface 14 of the rolled amber plate 12, a groove portion 19 that is one mode of a non-penetrating hole is provided at a location facing the second conductor pattern 38. The groove portions 18 and 19 in the present embodiment are formed substantially in parallel along the direction in which the second conductor pattern 38 extends (see FIG. 7). The width of the grooves 18 and 19 is set to be about 1.5 to 3 times larger than the line width of the second conductor pattern 38. The depths of the grooves 18 and 19 are both equal and set to about 1/4 of the thickness of the rolled amber plate 12.
[0037]
The rolled amber plate 12 is 13 side When viewed from above, the groove portion 18 provided on the upper surface 13 side and the groove portion 19 provided on the lower surface 14 side are arranged in a state shifted in the substrate surface direction so as not to overlap.
[0038]
The first resin insulation layers 21 and 22 have a thickness of 25 μm and are made of a resin-resin composite material in which continuous porous PTFE is impregnated with an epoxy resin. The first resin insulation layers 21 and 22 are formed on the upper surface 13 and the lower surface 14 of the rolled amber plate 12. The metal plate through-hole 15 is filled with an epoxy resin derived from the resin-resin composite material, thereby forming a resin filler 23.
[0039]
Each of the wiring layers 31 and 32 is made of copper having a thickness of about 15 μm (15 to 40 μm), and is formed on the first resin insulating layers 21 and 22, respectively. A via hole forming hole 33 having a diameter of 70 μm is formed in the first resin insulating layers 21 and 22. A via conductor 35 is formed in the via hole forming hole 33 by electroless copper plating, thereby forming a blind via hole conductor 34 (first via hole conductor). Via the blind via hole conductor 34, the connection between the rolled amber plate 12 and the wiring layer 31 and the connection between the rolled amber plate 12 and the wiring layer 32 are established.
[0040]
The second resin insulation layers 41 and 42 have a thickness of 20 μm and are formed on the second resin insulation layers 21 and 22 using a photosensitive epoxy resin. Via hole forming holes 63 and 64 are formed through the second resin insulating layers 41 and 42. In the via hole forming holes 63 and 64, mortar-shaped pads 71 and 72 made of three layers of conductors, ie, a copper plating layer, a nickel plating layer, and a gold flash plating layer (all not shown) are formed. The bottom of the pad 71 is connected and connected to the wiring layer 31, and the bottom of the pad 72 is connected and connected to the wiring layer 32. These pads 71 and 72 are connected to connection terminals such as an IC chip and a mother board (not shown) by soldering or the like. The second resin insulation layers 41 and 42 also serve as solder resist layers.
[0041]
The first resin insulation layers 21 and 22 and the resin filler 23 are formed with via hole forming holes 25 having a diameter of 0.15 mm that pass through them. A via conductor 27 made of copper plating is formed inside the via hole forming hole 25, and as a result, a metal plate insulating via hole conductor 26 (second via hole conductor) is formed. The metal plate insulating via-hole conductor 26 is connected and conductive between the wiring layer 31 on the upper surface side and the wiring layer 32 on the lower surface side while maintaining insulation between the inner wall surface of the metal plate through hole 15 of the rolled amber plate 12. ing.
[0042]
A so-called metal core package can be obtained by mounting an IC chip or the like (not shown) on such a laminated resin wiring substrate 11. When such a package is energized, the rolled amber plate 12 has a predetermined potential (such as a ground potential or a power supply potential) through the blind via-hole conductor 34, and functions as a ground layer or a power supply layer.
[0043]
Next, a procedure for manufacturing the laminated resin wiring board 11 having the above configuration will be described.
[0044]
First, a rolled amber plate 12 having a thickness of 0.25 mm is prepared (see FIG. 2). Then, a photosensitive resist is formed on the upper surface 13 and the lower surface 14 of the rolled amber plate 12, and exposure / development is performed to form a metal plate through-hole forming mask 81 having a predetermined pattern. In the mask 81, an opening 82 is provided at a position where the metal plate through hole 15 is to be formed (see FIG. 3).
[0045]
In this state, the rolled amber plate 12 is simultaneously etched from both sides with a conventionally known etchant (here, ferric chloride) capable of dissolving the Fe—Ni alloy. Here, the etching depth from one side is set to be more than half of the thickness of the rolled amber plate 12 (specifically, 0.15 mm) in order to set the condition that the eroded portions by etching reliably communicate with each other inside. Degree).
[0046]
When the double-sided simultaneous etching is performed under such conditions, the rolled amber plate 12 is eroded from both the upper surface 13 and the lower surface 14, and the eroded portions communicate with each other inside. A plate through hole 15 is formed. Thereafter, the mask 81 that is no longer needed is dissolved and removed with a special stripping solution (see FIG. 4).
[0047]
Next, a photosensitive resist is formed on the upper surface 13 and the lower surface 14 of the rolled amber plate 12, and a groove forming mask 91 having a pattern different from the previous one is formed by performing exposure and development. . In the mask 91, an opening 92 is provided at a position where the groove portions 18 and 19 are to be formed (see FIG. 5).
[0048]
In this state, the rolled amber plate 12 is simultaneously etched from both sides by the etchant capable of dissolving the Fe—Ni alloy. However, half-etching is performed by setting conditions such that the eroded portions due to etching do not communicate with each other inside. That is, the etching depth from one side is set to about 1/4 (specifically, about 0.06 mm) of the thickness of the rolled amber plate 12.
[0049]
When the double-sided simultaneous etching is performed under such conditions, the rolled amber plate 12 is eroded from both the upper surface 13 and the lower surface 14, and the groove portions 18 and 19 (non-penetrating hole portions) are formed at positions where the openings 92 are present. Each is formed. Thereafter, the mask 91 that has become unnecessary is dissolved and removed with a special stripping solution (see FIGS. 6 and 7).
[0050]
Next, first resin insulation layers 21 and 22 and a resin filler 23 are formed on the rolled amber plate 12. Here, first, the copper foil 83 having a thickness of 20 μm is formed on the upper surface 13 and the lower surface 14 of the rolled amber plate 12 through a prepreg (not shown) in which continuous porous PTFE is impregnated with a semi-cured epoxy resin, respectively. 84 are overlapped. Then, the laminate is subjected to vacuum thermocompression bonding with a vacuum hot press machine (not shown), so that the semi-cured prepreg is fully cured, whereby the resin insulating layers 21 and 22 having a thickness of 30 μm are respectively formed. Form. At this time, as a result of filling the metal plate through-hole 15 with the epoxy resin oozed from the prepreg, a resin filler 23 is formed (see FIG. 8). At this time, the grooves 18 and 19 are also completely filled with the epoxy resin oozed from the prepreg.
[0051]
Next, by carrying out laser drilling using a YAG laser or a carbon dioxide laser, the first resin insulation layers 21 and 22, the resin filler 23, and the copper foils 83 and 84 are perforated, and the diameter is 70 μm. Via hole forming holes 25 and 33 are formed. In the present embodiment, it is necessary to set the laser output and the like under conditions that do not pierce the rolled amber plate 12.
[0052]
Next, a via conductor 35 is formed in the via hole forming hole 33 and a via conductor 27 is formed in the via hole forming hole 25 by a conventionally known method. As a result, the blind via hole conductor 34 and the metal plate insulating via hole conductor 26 are formed (see FIG. 9). Further, the first wiring layers 31 and 32 are respectively formed on the first resin insulating layer 21 and the lower surface of the resin insulating layer 22 by a known method. Of the conductor patterns 37 and 38 constituting the wiring layers 31 and 32, the second conductor pattern 38 that requires higher insulation reliability is patterned so as to be disposed corresponding to the groove portions 18 and 19. Do.
[0053]
Specifically, after electroless copper plating, exposure / development is performed to form a predetermined pattern of plating resist. In this state, after electrolytic copper plating is performed using the electroless copper plating layer as a common electrode, first, the resist is dissolved and removed, and further unnecessary electroless copper plating layer is removed by etching.
[0054]
Next, an epoxy resin is filled in the blind via-hole conductor 34 and the metal plate insulating via-hole conductor 26, and the plug body 28 is formed by curing the epoxy resin. Further, the copper foils 83 and 84 are superposed on the first resin insulating layers 21 and 22 via a prepreg, and are pressure-bonded and cured by vacuum hot pressing. As a result, the second resin insulating layers 41 and 42 and the copper foils 83 and 84 are laminated (see FIG. 10).
[0055]
Next, by carrying out laser drilling, via-hole forming holes 63 and 64 are drilled and via conductors are formed. Further, electroless copper plating is performed on the copper foils 83 and 84 and the via hole forming holes 63 and 64 using a conventionally known method. Next, unnecessary portions of the electrolytic copper plating and copper foils 83 and 84 are etched, and electroless nickel plating and electroless gold plating are sequentially performed to form pads 71 and 72. As a result, the laminated resin wiring substrate 11 shown in FIG. 1 is completed.
[0056]
Therefore, according to the present embodiment, the following effects can be obtained.
[0057]
(1) In the laminated resin wiring board 11 of the present embodiment, even if there is a second conductor pattern 38 that is required to have higher insulation reliability than the first conductor pattern 37, the rolled amber plate 12 faces it. Groove portions 18 and 19 are provided at the locations to be performed. And about the location in which the groove parts 18 and 19 were provided, the distance from the 2nd conductor pattern 38 to the surface of the rolling amber board 12 becomes large. For this reason, even if the thickness of the resin insulation layers 21 and 22 is set to the insulation thickness required for the first conductor pattern 37, only the insulation reliability between the first conductor pattern 37 and the rolled amber plate 12 is obtained. In addition, the insulation reliability between the second conductor pattern 38 and the rolled amber plate 12 is also ensured. In addition, according to the present embodiment, the thickness of the resin insulating layers 21 and 22 may be set to an insulating thickness required for the first conductor pattern 37, so that the dimension in the substrate thickness direction can be sufficiently suppressed. It becomes possible. Therefore, it is possible to surely meet the demands for reducing the thickness and thickness of the laminated resin wiring board 11.
[0058]
(2) Further, according to the manufacturing method of the present embodiment using the half etching method, the above excellent laminated resin wiring substrate 11 can be obtained relatively easily and without reducing productivity and cost. Can do.
[0059]
In addition, you may change embodiment of this invention as follows.
[0060]
FIG. 11 shows a laminated resin wiring board 11 according to another embodiment. In this laminated resin wiring substrate 11, the groove portions 18 and 19 are deeper than those of the above-described embodiment, and are more than half the thickness of the rolled amber plate 12 (metal plate). The laminated resin wiring board 11 can be formed using, for example, a groove forming mask 101 that also serves as a metal plate through hole mask. That is, in the mask 101, an opening 92 is provided at a location where the groove portions 18 and 19 are to be formed, and an opening 82 is provided at a location where the metal plate through hole 15 is to be formed (see FIG. 12). ). Therefore, when the double-sided simultaneous etching is performed, the groove portions 18 and 19 and the metal plate through hole 15 are simultaneously formed (see FIG. 13). Therefore, the number of masks can be reduced by one compared with the case of the above embodiment, and the man-hour can be reduced by that amount.
[0061]
-The formation method of the groove parts 18 and 19 (non-penetrating hole part) is not limited only to the etching method as shown in the embodiment, and other methods may be used. For example, a mechanical processing method such as grinding may be employed, or a processing method of partially forming a dent by pressing with a mold may be employed.
[0062]
In the embodiment, the groove portions 18 and 19 provided to face the second conductor pattern 38 are provided in a state in which they are not connected to the metal plate through holes 15 around them. And may be provided in a partially connected state.
[0063]
In addition, as the resin insulating layers 21, 22, 41, 42, those obtained by curing a prepreg obtained by impregnating an epoxy resin into continuous porous PTFE were used, but it is obvious that other materials may be used, for example, A glass fiber-epoxy resin composite material or the like can be used.
[0064]
In the above embodiment, a specific example of the laminated resin wiring board 11 using only one rolled amber plate 12 (metal plate) as a core material has been shown. Of course, the present invention is not limited to such an embodiment. For example, the rolled amber plate 12 (metal plate) can be embodied as a laminated resin wiring board using two or more sheets. With such a structure, the low thermal expansion of the entire substrate can be achieved more reliably, and more than one core material can have various functions. For this reason, it is possible to achieve higher reliability and higher functionality.
[0065]
In the above embodiment, the same number of resin insulating layers 21, 22, 41, 42 and wiring layers 31, 32 are formed on the top and bottom of the core material. Of course. Of course, the number of wiring layers 31 and 32 may be two or more on one side to further increase the number of layers.
[0066]
In the above embodiment, a specific example of the laminated resin wiring substrate 11 using the rolled amber plate 12 (metal plate) as a core material and having build-up layers on the upper and lower sides thereof is shown. Of course, the present invention is not limited to such an embodiment. For example, the rolled amber plate 12 (metal plate) can be used as a base material and can be embodied as a laminated resin wiring substrate (so-called metal base substrate) having a buildup layer only on one of the upper and lower sides thereof.
[0067]
Next, in addition to the technical ideas described in the claims, the technical ideas grasped by the embodiment described above are listed below.
[0068]
(1) The laminated resin wiring board according to claim 3, wherein the width of the groove is set to be larger than the line width of the second conductor pattern.
[0069]
(2) The width of the groove is set to 1.5 to 10 times (particularly 1.5 to 3 times) the line width of the second conductor pattern. The laminated resin wiring board described.
[0070]
(3) The depth of the non-penetrating hole is less than half of the thickness of the metal plate (1/100 to 1/3, particularly 1/10 to 1/3 of the thickness of the metal plate). The laminated resin wiring board according to claim 2, wherein the laminated resin wiring board is set.
[0071]
(4) When a non-penetrating hole is formed in both the first main surface and the second main surface of the metal plate, the non-penetrating hole provided on the first main surface side, and the first 3. The non-through holes provided on the two principal surface sides are arranged in a state of being shifted in the substrate surface direction so as not to overlap each other when viewed from the first principal surface side. Or the laminated resin wiring board of 3.
[0072]
(5) The laminated resin wiring board according to claim 2 or 3, wherein a resin for forming an insulating layer is buried in the hole.
[0073]
(6) A metal plate made of a rolled Fe—Ni alloy material having a first main surface and a second main surface and having a thickness of 150 μm or more, and located on the first main surface side and the second main surface side of the metal plate. A plurality of wiring layers, a plurality of resin insulating layers interposed between the metal plate and the wiring layer, or between the metal plate and the wiring layer and between the wiring layers, and formed in the resin insulating layer, A first via-hole conductor that connects and connects the wiring layer and the metal plate, and a resin filling that fills the metal plate through-hole that communicates the first main surface and the second main surface of the metal plate And a wiring layer on the first main surface side and a wiring layer on the second main surface side while maintaining insulation between the body and the via hole forming hole penetrating the resin filler. A second via-hole conductor connecting and conducting between the wiring layers, and the wiring layer between the metal plate A first conductor pattern that requires insulation reliability; and a second conductor pattern that requires higher insulation reliability than the first conductor pattern between the metal plate and the metal. A portion of the plate facing the second conductor pattern is formed substantially in parallel along the direction in which the second conductor pattern extends, and the width thereof is larger than the line width of the second conductor pattern. The laminated resin wiring board is characterized in that a groove portion whose depth is set to less than half of the thickness of the metal plate is provided.
[Brief description of the drawings]
FIG. 1 is a schematic partial cross-sectional view showing a laminated resin wiring board according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional schematic view showing a rolled amber plate that is a component of the wiring board.
FIG. 3 is a partial cross-sectional schematic view showing a state where a photoetching mask is formed on a rolled amber plate.
FIG. 4 is a partial cross-sectional schematic view showing a state where metal plate through holes are formed by photoetching.
FIG. 5 is a partial cross-sectional schematic view showing a state in which another photoetching mask is formed on a rolled amber plate.
FIG. 6 is a partial cross-sectional schematic view showing a state in which a groove is formed by photoetching.
FIG. 7 is a partial plan view showing a state in which a groove is formed by photoetching.
FIG. 8 is a partial cross-sectional schematic view showing a state in which a first resin insulating layer and a copper foil are laminated.
FIG. 9 is a partial cross-sectional schematic view showing a state in which various via-hole conductors are formed in the first resin insulating layer.
FIG. 10 is a partial cross-sectional schematic view showing a state in which a second resin insulating layer and a copper foil are laminated.
FIG. 11 is a partial cross-sectional schematic view showing a laminated resin wiring board of another embodiment embodying the present invention.
FIG. 12 is a partial cross-sectional schematic view showing a state in which a photoetching mask is formed on a rolled amber plate in manufacturing the laminated resin wiring board.
FIG. 13 is a partial cross-sectional schematic view showing a state in which a groove is formed by photoetching.
[Explanation of symbols]
11 ... Laminated resin wiring board
12 ... Rolled amber plate which is a metal plate
13 ... Upper surface as the first main surface
14 ... lower surface which is the second main surface
18, 19 ... Groove as a hole
21, 22, 41, 42 ... resin insulation layer
31, 32 ... wiring layer
37 ... 1st conductor pattern which comprises a wiring layer
38 ... Second conductor pattern constituting the wiring layer

Claims (4)

A metal plate having a first main surface and a second main surface; a wiring layer positioned on at least one of the first main surface and the second main surface; and the metal plate and the wiring layer. A resin insulating layer interposed therebetween, and the wiring layer includes a first conductor pattern that requires a predetermined insulation reliability between the metal plate and the first metal pattern between the first metal pattern and the first metal pattern. And a second conductor pattern that is required to have higher insulation reliability than the conductor pattern, and a hole is provided at a location facing the second conductor pattern in the metal plate. A laminated resin wiring board. The laminated resin wiring board according to claim 1, wherein the hole is a non-penetrating hole. The multilayer resin wiring board according to claim 2, wherein the hole is a groove formed substantially in parallel along a direction in which the second conductor pattern extends. Forming a non-penetrating hole by a half-etching method at a predetermined location in the metal plate having the first main surface and the second main surface;
Forming a resin insulating layer on at least one of the first main surface and the second main surface of the metal plate in which the hole is formed;
A first conductor pattern that requires a predetermined insulation reliability between the metal plate and a second conductor that requires a higher insulation reliability than the first conductor pattern between the metal plate. Forming a wiring layer having a conductor pattern on the resin insulation layer, and placing the second conductor pattern corresponding to the hole at that time. Manufacturing method.

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