JP2004095757A - Laminated metal plate wiring board and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laminated metal plate wiring board which can be improved in productivity and manufactured at a lower cost through a shortened manufacturing process, by forming a high-power interconnect line region having a thicker pattern at the same time when the interlayer connector of a small-power interconnect line region is formed, and to provide its manufaturing method. <P>SOLUTION: The laminated metal plate wiring board is equipped with the small-power interconnect line region A1 where interconnect line patterns 11 are electrically connected together through the interlayer conductor 12, the large-power interconnect line region A2, and a metal plate 1 laminated on the large-power interconnect line region. The large-power interconnect line region A2 is equipped with a laminated pattern SP where an interlayer pattern 22 nearly as thick as the surrounding insulating layer 3 is formed on the surface of a reference pattern 21a that is formed as thick as the interconnect line pattern 11a of the small-power interconnect line region A1. The interlayer pattern 22 and the interlayer connector 12 of the small-power interconnect line region A1 are equipped with a first metal layer M1 formed by etching and a second metal layer M2 having etching-resistant properties. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a metal plate laminated wiring board including a low power wiring region in which a wiring pattern is conductively connected by an interlayer connector, a high power wiring region, and a metal plate laminated at least on the high power wiring region. And a method for producing the same.
[0002]
[Prior art]
The heat generated by electronic components mounted on the surface of the wiring board has been increasing due to higher density of mounting and higher performance of the components, and it is necessary to dissipate the heat generated through the wiring board. I have. In a wiring board such as a power supply board or an inverter board that conducts a large current, it is necessary to partially increase the conductor thickness for electric conduction efficiency and heat dissipation of conduction heat. For this purpose, countermeasures such as laminating a metal plate on a wiring board, increasing the thickness of copper foil for pattern conductors, and conducting heat and large current from the surface layer to the layer below the surface layer and the metal plate by plating through holes (For example, refer to JP-A-2002-43510).
[0003]
More specifically, a base copper, an insulating resin on a metal plate such as aluminum, a pattern region made of a thick copper foil for mounting a heat-generating component, and a pattern made of a thin copper foil for a circuit for controlling those electronic components A region is formed, a component mounting land is formed on the surface layer pattern, and the electronic component can be mounted by a method such as soldering or wire bonding.
[0004]
[Problems to be solved by the invention]
However, in such a metal-based wiring board, since the thickness of the thick copper foil and the thickness of the thin copper foil are different, it is necessary to separately form a pattern by etching, and then laminate and form the insulating resin on the metal base. Was. For this reason, in general, the two regions cannot be directly electrically connected by the wiring pattern, and must be connected at the time of component mounting by a method such as soldering or wire bonding, which requires processing time and costs.
[0005]
Further, in general, the metal plate is bonded and joined to the insulating resin layer integrally with the insulating resin layer from the time of the substrate material, and is heavy, so that handling and processing are difficult. Further, in the process of processing the copper foil into a circuit, a process of forming a mask for isolating and protecting the metal plate from chemicals for plating and etching is required, which has led to low mass productivity and high cost. In the case of processing a circuit pattern with a fine pattern, the yield of non-defective products is reduced, but defective costs to be discarded are increased because a defective product is provided with a metal plate. The through hole for electric connection and heat radiation between the layers is usually formed by copper plating, and the inner surface of the hole formed by drilling is plated with a thickness of, for example, about 0.02 mm. The conductivity was not sufficient. In addition, there was a danger that the copper plating in the through hole was fatigued and cut due to repeated heat generation and cooling.
[0006]
On the other hand, in recent years, various methods for manufacturing a multilayer wiring board in which plated through holes and inner vias are replaced with metal pillars have been proposed, and significant improvements can be made in terms of electrical conduction between layers and connection reliability (for example, WO 00/52977). Gazette). However, the application of this technique to a metal plate laminated wiring board has not been known so far, and the above-described problem peculiar to the metal plate laminated wiring board has not been improved yet.
[0007]
Therefore, an object of the present invention is to improve productivity and shorten the manufacturing process by simultaneously forming a high-power wiring region having a larger pattern thickness when forming an interlayer connector of a low-power wiring region. Another object of the present invention is to provide a metal-plate laminated wiring board capable of reducing costs. It is still another object of the present invention to provide a method of manufacturing a metal-plate laminated wiring board that can solve the problems of handleability, workability, and defective product cost due to pre-lamination of metal plates.
[0008]
[Means for Solving the Problems]
The above object can be achieved by the present invention as described below.
That is, the metal plate laminated wiring board of the present invention includes a low-power wiring region in which a wiring pattern is conductively connected by an interlayer connector, a high-power wiring region, and a metal plate laminated on at least the high-power wiring region. Wherein the high-power wiring area is formed on the surface of the reference pattern portion formed with the same thickness as the wiring pattern of the low-power wiring area, and the interlayer pattern having substantially the same thickness as the surrounding insulating layer. And the interlayer connector of the low-power wiring region has a first metal layer formed by etching, and exhibits resistance during etching of the first metal layer. A second metal layer provided on the reference pattern portion side. Here, the high-power wiring region refers to a region having a pattern in which the thickness of the wiring pattern is thicker than that of the low-power wiring region.
[0009]
ADVANTAGE OF THE INVENTION According to the metal plate laminated wiring board of this invention, the 1st metal layer formed by etching and the 1st metal layer and the etching of the 1st metal layer of the interlayer pattern part of a high-power wiring area and the interlayer connector of a low-power wiring area are formed. Since the first metal layer and the second metal layer are sometimes selectively etched, the stacked pattern of the high-power wiring region having a larger pattern thickness can be formed with a low power consumption. Can be formed at the same time as the formation of the interlayer connector in the wiring area for use. For this reason, the step of separately fabricating and laminating the two regions is not required, so that the productivity can be improved, the manufacturing process can be shortened, and the cost can be reduced.
[0010]
In the above, it is preferable that the high power wiring region and the low power wiring region are conductively connected by the wiring pattern or the laminated pattern. In this case, since the two regions were conventionally separately formed, it was necessary to make a separate conductive connection.However, since the two were conductively connected by the pattern of the wiring board, even when the conductive connection was additionally performed, the wiring was not performed. Can be reduced.
[0011]
Further, it is preferable that the first metal layer of the interlayer pattern portion is arranged and laminated on the metal plate side. In this case, since the mounting surface of the etching circuit pattern is opposite to the pattern of the normal wiring board, the pattern mounting surface is widened and the mountability is improved.
[0012]
On the other hand, the method for manufacturing a metal plate laminated wiring board according to the present invention includes a low-power wiring region in which a wiring pattern is conductively connected by an interlayer connector and a reference pattern portion formed at the same thickness as the wiring pattern. And a high-power wiring region having a laminated pattern in which an interlayer pattern portion having substantially the same thickness as the insulating layer is provided, and a metal plate is laminated and integrated at least in the high-power wiring region. It is characterized by. ADVANTAGE OF THE INVENTION According to the manufacturing method of this invention, since a metal plate is laminated and integrated after forming a wiring board, the problem of handleability, workability, and defective cost due to the metal plates being laminated in advance can be solved. . Specifically, the conventional metal plate, the outer shape processing of the composite material of the insulating layer is accompanied by difficulties due to the difference in the workability of the material, the occurrence of burrs, peeling of the metal plate, etc. occur, but in the present invention, The outer shape of the wiring board and the metal plate can be separately processed and bonded, and the above-described problem does not occur. Further, by laminating the metal plates later, the degree of freedom of the structure is increased. For example, a metal plate smaller in size than the wiring substrate is bonded only to the heat generating portion of the wiring substrate to reduce the overall weight. Conversely, the size of the metal plate can be made larger than that of the wiring board to improve heat dissipation. Further, a plurality of wiring boards can be collectively laminated on a metal plate, and then cut into individual metal plate laminated wiring boards.
[0013]
In the above, the interlayer pattern portion and the interlayer connector of the low-power wiring region are provided on the first metal layer formed by etching, and exhibit resistance during etching of the first metal layer, and are provided on the reference pattern portion side. And a second metal layer. In this case, since the interlayer pattern portion and the interlayer connector have the first metal layer formed by etching and the second metal layer having resistance during the etching, the first metal layer and the second metal layer are sequentially formed. By selectively etching, a laminated pattern of the high-power wiring region having a larger pattern thickness can be formed at the same time when the interlayer connector of the low-power wiring region is formed. For this reason, the step of separately fabricating and laminating the two regions is not required, so that the productivity can be improved, the manufacturing process can be shortened, and the cost can be reduced.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in order of structure and manufacturing method with reference to the drawings.
[0015]
〔Construction〕
FIG. 1 is a cross-sectional view showing an example of the metal plate laminated wiring board of the present invention. As shown in FIG. 1, the metal plate laminated wiring board of the present invention includes a low power wiring area A1 in which the wiring pattern 11 is conductively connected by an interlayer connector 12, a high power wiring area A2, and at least the high power wiring area A1. And a metal plate 1 laminated on the wiring area A2. The heat dissipation effect can be enhanced by laminating the metal plates 1. In the present embodiment, a metal plate 1 having the same size as a wiring board WB on which a low-power wiring area A1 and a high-power wiring area A2 are formed via a heat-conductive insulating layer 2 is integrated. An example is shown below.
[0016]
In the present invention, the high-power wiring region A2 is formed on the surface of the reference pattern portion 21a formed to have the same thickness as the wiring pattern 11a of the low-power wiring region A1. Is formed.
[0017]
The inter-layer pattern portion 22 and the inter-layer connector 12 in the low-power wiring region A1 are provided on the first metal layer M1 formed by etching and exhibit resistance during etching of the first metal layer M1, and are provided on the reference pattern portion 21a side. And a second metal layer M2 provided. The interlayer connector 12 in the low-power wiring area A1 is generally formed in a columnar or quadrangular prism shape.
[0018]
The stacked pattern SP may be composed of the reference pattern portion 21a and the interlayer pattern portion 22, but may have an upper layer pattern portion 23 on the upper surface of the interlayer pattern portion 22, as shown in FIG.
[0019]
The insulating layer 3 on which the upper layer pattern portion 23 and the upper layer wiring pattern 11b are formed is covered with a solder resist 5, and the upper layer pattern portion 23 and the upper layer wiring pattern 11b exposed from the opening are provided with a surface made of a noble metal or the like. The plating layer 6 is formed.
[0020]
FIG. 2 is a sectional view showing another example of the metal plate laminated wiring board of the present invention. In this embodiment, the number of layers is increased, and the high-power wiring area A2 and the low-power wiring area A1 are conductively connected by the wiring pattern 7. Specifically, the wiring pattern 11a of the low-power wiring area A and the reference pattern portion 21a of the high-power wiring area A2 are integrally formed with the wiring pattern 7 interposed therebetween. However, instead of the wiring pattern 7, the high-power wiring area A2 and the low-power wiring area A1 may be conductively connected by a laminated pattern SP.
[0021]
Further, the laminated pattern SP of the high-power wiring area A2 includes another interlayer pattern section 24 below the reference pattern section 21a, and penetrates the lower insulating layer 4. Since this interlayer pattern portion 24 is in contact with the insulating layer 2 having good heat conductivity over a large area, heat can be satisfactorily radiated from the metal plate 1 via the insulating layer 2. The same applies to the heat radiation pattern portion 14 provided below the wiring pattern 11a in the low power wiring region A1.
[0022]
FIG. 3 is a sectional view showing another example of the metal plate laminated wiring board of the present invention. In this embodiment, the number of wiring layers is increased as compared with the embodiment shown in FIG. 2 so that the high-power wiring area A2 and the low-power wiring area A1 are conductively connected by a plurality of wiring patterns 7. .
[0023]
In this example, the laminated pattern SP of the high-power wiring region A2 has a structure in which a reference pattern portion 21a, an interlayer pattern portion 22, an upper reference pattern portion 21b, an interlayer pattern portion 22, and an upper layer pattern portion 23 are laminated. . The reference pattern portion 21a and the upper-layer reference pattern portion 21b are formed integrally with the wiring patterns 11a and 11b of the low-power wiring region A1 via the wiring pattern 7.
[0024]
By designing the lowermost wiring pattern 7 continuous from the reference pattern portion 21a to have an area as large as possible, heat radiation from the metal plate 1 via the insulating layer 2 can be performed more favorably.
[0025]
FIG. 4 is a cross-sectional view showing another example of the metal plate laminated wiring board of the present invention. In this embodiment, an example is shown in which a wiring board WB is stacked on a metal plate 1 in a direction opposite to that shown in FIGS. 1 to 3, and the metal plate 1 has a larger area than the wiring board WB. That is, the first metal layer M1 of the interlayer pattern section 22 is arranged and laminated on the metal plate 1 side.
[0026]
Also in this example, as shown in FIG. 4, the wiring pattern 11 is laminated on the low-power wiring area A1, the high-power wiring area A2, and at least the high-power wiring area A2, which are conductively connected by the interlayer connector 12. Metal plate 1 provided.
[0027]
In the high-power wiring area A2, an interlayer pattern section 22 having substantially the same thickness as the surrounding insulating layer 3 is formed on the surface of the reference pattern section 21a formed to have the same thickness as the wiring pattern 11a in the low-power wiring area A1. Having the laminated pattern SP.
[0028]
The inter-layer pattern portion 22 and the inter-layer connector 12 in the low-power wiring region A1 are provided on the first metal layer M1 formed by etching and exhibit resistance during etching of the first metal layer M1, and are provided on the reference pattern portion 21a side. And a second metal layer M2 provided. The stacked pattern SP is configured by stacking a reference pattern portion 21a, an interlayer pattern portion 22, a lower reference pattern portion 21c, and a lower interlayer pattern portion 24. Also in this embodiment, as in the structure shown in FIGS. 2 and 3, the high-power wiring region A2 and the low-power wiring region A1 may be conductively connected by the wiring pattern 7 or the laminated pattern SP. Further, a surface plating layer 6 made of a noble metal or the like may be formed on a portion of the reference pattern portion 21a and the wiring pattern 11a exposed from the opening of the solder resist 5.
[0029]
The metal plate 1 having a larger area than the wiring board WB has a mounting hole 1a such as a radiation fin or a radiation frame at a portion where the wiring substrate WB is not laminated. Contrary to this example, the metal plates 1 having a smaller area than the wiring board WB may be stacked. Note that the metal plate 1 in the present invention only needs to have a plate portion for laminating the wiring boards WB, and may have ribs, posts, bumps, and the like for improving heat radiation efficiency.
[0030]
In the structure in which the first metal layer M1 of the interlayer pattern portion 22 is disposed and laminated on the metal plate 1 side, the mounting surface of the etched pattern is opposite to the pattern of the normal wiring board, so that the pattern mounting surface is wide. The mountability is improved. In other words, when a pattern is formed by processing a copper foil by normal etching, the surface (top surface) is over-etched and the area is narrow because the copper foil is etched sequentially from the surface to the bottom surface, while the bottom surface (bottom surface) is The area increases due to insufficient etching. The cross-sectional shape becomes trapezoidal, and in actual work, the top and bottom areas are controlled within the allowable range by adjusting the speed of the etching line. In the above structure, the bottom surface can be used as a component mounting pattern. Therefore, the pattern is not thinned due to excessive etching, and the improvement in productivity is expected due to the ease of the etching conditions and the improvement in the mounting performance due to the large mounting area.
[0031]
As described above, in the metal plate laminated wiring board of the present invention, for example, a power element, which is a semiconductor element constituting an electronic control circuit, is mounted in the high-power wiring area A2. Various electronic components constituting the control circuit are mounted on A1.
[0032]
(Production method)
5 to 9 are process diagrams showing an example of the method for manufacturing a metal plate laminated wiring board of the present invention. This example corresponds to the case of manufacturing the metal plate laminated wiring board shown in FIG. 4 (however, the area of the wiring board WB and the metal plate 1 is the same).
[0033]
First, as shown in FIG. 5A, a circuit metal plate 31 corresponding to the size and shape of the wiring board WB is prepared. The circuit metal plate 31 is a member that becomes the reference pattern portion 21a and the wiring pattern 11a by the later half etching. Accordingly, as a material of the circuit metal plate 31, copper, silver, nickel, tin, a copper alloy or the like can be used, but copper or a copper alloy is preferable. The thickness of the circuit metal plate 31 may be thicker than the wiring pattern 11a, for example, 10 to 300 μm can be used.
[0034]
Next, as shown in FIG. 5 (2), a layer 32 that becomes a second metal layer having resistance when the first metal layer is etched is formed on both surfaces of the circuit metal plate 31. The method for forming the layer 32 may be any of electroless plating, a combination of electroless plating and electrolytic plating, and a combination of sputtering, vapor deposition and electrolytic plating, but electrolytic plating is preferred. The thickness of the layer 32 is preferably 0.5 to 10 μm.
[0035]
As a metal constituting the layer 32 (that is, a metal constituting the second metal layer M2), gold, silver, zinc, palladium, ruthenium, nickel, rhodium, lead-tin-based solder is used as a metal having resistance during etching of copper. An alloy or a nickel-gold alloy is used.
[0036]
The above-mentioned electrolytic plating can be performed by a well-known method. Generally, while immersing the target circuit metal plate 31 in a plating bath, it is used as a cathode to supply metal ions of the metal to be plated. This is performed by using an anode as a source and depositing a metal on the cathode side by an electrolysis reaction.
[0037]
Next, as shown in FIG. 5C, a layer 33 which will be the first metal layer M1 of the interlayer pattern portion 22 and the interlayer connector 12 is formed on the layers 32 formed on both surfaces. The formation of the layer 33 is preferably performed by electrolytic plating. As the metal constituting the layer 33 (that is, the metal constituting the first metal layer M1), copper, silver, nickel, tin, a copper alloy, or the like can be used, but copper or a copper alloy is preferable. The thickness of the layer 33 is, for example, 20 to 200 μm, and corresponds to the height of the interlayer pattern portion 22 and the like at which this thickness is obtained.
[0038]
In other words, in the present invention, the interlayer connector 12 in the interlayer pattern portion 22 and the low-power wiring region A1 shows the first metal layer M1 formed by etching, the resistance when the first metal layer M1 is etched, and the reference pattern. It is preferable to have the second metal layer M2 provided on the part 21a side.
[0039]
Next, as shown in FIG. 5D, after selectively etching the layer 33, the layer 32 is selectively etched to form the interlayer pattern portion 22 and the interlayer connector 12. At this time, the back layer 33 and the layer 32 are removed by etching.
[0040]
At the time of the first selective etching, an etching mask is formed on the surface of the layer 33 according to the position and shape of the interlayer pattern portion 22 and the interlayer connector 12. As a method of forming a mask, a method of forming by various printing methods, a method of exposing and developing a dry film or a photosensitive resin for photoresist, a method of forming by transfer, a method of forming by transfer, a method using a metal-based resist, and the like Either may be used.
[0041]
For example, when the layer 33 is made of copper and the layer 32 is made of the above-mentioned metal (including a metal-based resist), a commercially available alkali etching solution, ammonium persulfate, hydrogen peroxide / sulfuric acid, or the like can be used for etching the layer 33. .
[0042]
In the etching of the layer 32, for example, when the layer 33 is copper and the layer 32 is the above-described metal (including a metal-based resist), a nitric acid-based, sulfuric acid-based, cyan-based, or the like that is commercially available for solder stripping It is preferable to use an acid-based etching solution or the like.
[0043]
The removal of the mask may be appropriately selected depending on the type of the mask, such as removal of a chemical agent and removal of a mask. For example, in the case of a photosensitive ink formed by screen printing, it is removed with a chemical such as alkali. In the case of a dry film resist, methylene chloride, sodium hydroxide, or the like is used.
[0044]
Next, as shown in FIG. 6 (5), the insulating layer 3 in which the interlayer pattern portion 22 and the interlayer connector 12 are exposed on the surface is formed. The insulating layer 3 is formed by first applying or laminating an insulating material for forming an insulating layer on the surface. As the insulating material, for example, a thermosetting epoxy resin or a polyimide resin or the like can be used in a liquid or sheet form, and this is applied or laminated by various methods so as to be slightly thicker than the height of the interlayer pattern portion 22 or the like. Then, it may be cured by heating or light irradiation. As a method of application or lamination, a hot press and various coaters are used.
[0045]
Next, the cured insulating material is ground and polished to expose the upper surfaces of the interlayer pattern portions 22 and the like. Examples of the grinding method include a method using a grinding device having a hard rotary blade in which a plurality of hard blades made of diamond or the like are arranged in a radial direction of a rotary plate. By moving along the upper surface of the wiring board, the upper surface can be flattened. Examples of the polishing method include a method of lightly polishing by a belt sander, buffing, or the like.
[0046]
Next, as shown in FIG. 6 (6), a layer 34 to be a lower reference pattern portion 21c and a wiring pattern 11b in a later step is formed. As a metal constituting the layer 34, copper, silver, nickel, tin, a copper alloy, or the like can be used, but copper or a copper alloy is preferable. The method for forming the layer 34 may be any of electroless plating, a combination of electroless plating and electrolytic plating, and a combination of sputtering, vapor deposition and electrolytic plating, and preferably includes electrolytic plating.
[0047]
For the electroless plating, a plating solution such as copper, nickel, tin or the like is usually used. These metals may be the same as or different from the metals constituting the interlayer pattern section 22 and the like. Plating solutions for electroless plating are well known for various metals, and various plating solutions are commercially available. Generally, the liquid composition contains a metal ion source, an alkali source, a reducing agent, a chelating agent, a stabilizer and the like. Prior to the electroless plating, a plating catalyst such as palladium may be deposited.
[0048]
Next, as shown in FIG. 6 (7), the layer 34 is etched to form the reference pattern portion 21c and the wiring pattern 11b. At this time, the back layer 34 is removed by etching. For the etching, a mask corresponding to the shape of the reference pattern portion 21c is used as in the case of forming a normal wiring pattern.
[0049]
Next, as shown in FIG. 7 (8), a layer 35 and a layer 36 are sequentially formed. The layer 35 is a layer for protecting the reference pattern portion 21c and the wiring pattern 11b when the layer 36 is etched, and is formed in the same manner as the layer 32 described above. Therefore, the layer 35 corresponds to the second metal layer M2. The layer 36 is a layer to be the lower interlayer pattern portion 24 in a later step, and is formed in the same manner as the layer 33 described above. Therefore, the layer 36 corresponds to the first metal layer M1.
[0050]
When forming the layer 35, it is preferable to form the underlying conductive layer by electroless plating copper or the like in advance and then to form the layer 35 by electrolytic plating. In that case, the underlying conductive layer remaining after the etching of the layer 35 can be removed by soft etching. Examples of the method of soft etching include a method of using an etching solution for a metal constituting the underlying conductive layer at a low concentration, a method of using the etching solution under mild etching conditions, and the like.
[0051]
Next, as shown in FIG. 7 (9), after selectively etching the layer 36, the layer 35 is selectively etched to form the lower interlayer pattern section 24. At this time, the layers 36 and 35 on the back side are removed by etching.
[0052]
Next, as shown in FIG. 7 (10), the insulating layer 4 having the interlayer pattern portion 24 exposed on the surface is formed. This insulating layer 4 is formed in the same manner as the insulating layer 3. Thereby, the wiring board WB for lamination is manufactured.
[0053]
Next, as shown in FIG. 8 (11), the insulating layer 4 of the wiring board WB and the metal plate 1 are laminated and integrated via the insulating layer 2 having good heat conductivity. In other words, the method for manufacturing a metal plate laminated wiring board according to the present invention includes the low power wiring region A1 in which the wiring pattern 11 is conductively connected by the interlayer connector 12, and the reference pattern portion 21c formed with the same thickness as the wiring pattern 11. And a high-power wiring area A2 having a laminated pattern SP in which an interlayer pattern portion 24 having substantially the same thickness as the surrounding insulating layer 4 is formed on the surface of the wiring board WB. And a step of laminating and integrating the plates 1. In the wiring board WB provided for lamination in the manufacturing method of the present invention, the wiring pattern 11 and the reference pattern portion 21c may be a plate (circuit metal plate 31) before pattern formation.
[0054]
Although the insulating layer 2 having good heat conductivity may be integrated with the metal plate 1 in advance as shown in the drawing, the insulating layer 2 having good heat conductivity may be formed on the wiring board WB side, or the metal plate 1 and the insulating layer 2, and the wiring board WB may be separately laminated. As a material of the metal plate 1, aluminum, copper, iron, stainless steel, or the like is preferable.
[0055]
As the insulating layer 2 having good heat conductivity, a material that can be adhered to the insulating layer 4 of the wiring board WB or the metal plate 1 by heating and pressing can be used, and various thermosetting resins such as a polyimide resin and an epoxy resin are removed. Materials. In order to obtain good heat transfer, it is preferable to disperse the ceramic particles or to reduce the thickness of the insulating layer 2 as much as possible. From this point and the point of obtaining reliable insulation, the thickness of the insulating layer 2 is preferably 30 to 250 μm.
[0056]
Next, as shown in FIG. 9 (12), the entire layer 31 is half-etched to form the layer 31a so that the thickness of the reference pattern portion 21a and the wiring pattern 11a becomes the same after the etching. The half-etching is performed using an etching solution corresponding to the metal of the layer 31, and the thickness can be adjusted by adjusting the concentration or the etching time.
[0057]
Next, as shown in FIG. 9 (13), the layer 31a is etched to form the reference pattern portion 21a and the wiring pattern 11a. The etching can be performed in the same manner as the layer 34. Further, the insulating layer 3 is covered with the solder resist 5 by printing or the like so that the reference pattern portion 21a and the wiring pattern 11a are exposed from the opening. A surface plating layer of a noble metal or the like is formed in the opening as required.
[0058]
[Other embodiments]
(1) In the present invention, the following manufacturing method can be performed instead of the above manufacturing method. In this embodiment, as shown in FIG. 10, an interlayer pattern portion 22 and an interlayer connector 12 to be formed first are formed by half etching.
[0059]
First, as shown in FIG. 10A, a half-etching metal plate 41 is prepared according to the size and shape of the wiring board WB. The metal plate 41 is a member for forming the interlayer pattern part 22 and the interlayer connector 12 by the next half etching. Accordingly, as a material of the metal plate 41, copper, silver, nickel, tin, a copper alloy or the like can be used, but copper or a copper alloy is preferable.
[0060]
Next, as shown in FIG. 10B, the metal plate 41 is half-etched to form the interlayer pattern portion 22 and the interlayer connector 12 on the upper surface of the plate portion 41a. At the time of half-etching, an etching mask is formed on one surface of the metal plate 41 in accordance with the position and shape of the interlayer pattern portion 22 and the interlayer connector 12. Further, an etching mask may be formed on the entire back surface. For the half etching, for example, when the metal plate 41 is copper, a commercially available alkali etching solution, ammonium persulfate, hydrogen peroxide / sulfuric acid, or the like can be used.
[0061]
Next, as shown in FIG. 10C, the insulating layer 3 in which the interlayer pattern portion 22 and the interlayer connector 12 are exposed on the surface is formed. The method for forming the insulating layer 3 is as described above. Further, as shown in FIG. 10D, a layer 42 to be the lower reference pattern portion 21c and the wiring pattern 11b is formed in a later step. The layer 42 can be formed in a manner similar to that of the layer 34. The following steps are the same as the manufacturing method shown in FIGS.
[0062]
(2) In the above-described embodiment, the example in which the wiring pattern is formed by etching has been described, but the wiring pattern may be formed by pattern plating. In that case, a dry film resist or the like can be used as the plating resist.
[0063]
(3) In the above-described embodiment, when forming the layers 32 to 36, the respective layers are also formed on the back surface by plating or the like, and the respective layers on the back side are later removed by etching. Alternatively, a mask layer may be formed on the back surface so that each layer is not formed on the back surface.
[0064]
(4) In the above-described embodiment, as an example of the manufacturing method of the present invention, an example in which a metal plate is laminated and integrated on the previously manufactured wiring board has been described. Instead, it may be manufactured by a method of forming a wiring board on a metal plate by build-up.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a metal-plate laminated wiring board of the present invention.
FIG. 2 is a sectional view showing another example of the metal plate laminated wiring board of the present invention.
FIG. 3 is a sectional view showing another example of the metal plate laminated wiring board of the present invention.
FIG. 4 is a sectional view showing another example of the metal plate laminated wiring board of the present invention.
FIG. 5 is a process chart (1) to (4) showing an example of a method for manufacturing a metal plate laminated wiring board of the present invention.
FIG. 6 is a process chart (5) to (7) showing an example of a method for manufacturing a metal plate laminated wiring board of the present invention.
FIG. 7 is a process drawing (8) to (10) showing an example of the method for manufacturing a metal plate laminated wiring board of the present invention.
FIG. 8 is a process diagram (11) showing an example of the method for manufacturing a metal-plate laminated wiring board of the present invention.
FIG. 9 is a process chart (12) to (13) showing an example of a method for manufacturing a metal plate laminated wiring board of the present invention.
FIG. 10 is a process chart (1) to (4) showing another example of the method for manufacturing a metal plate laminated wiring board of the present invention.
[Explanation of symbols]
1 metal plate
3 insulating layer
11 Wiring pattern
12 interlayer connection
21a Reference pattern part
22 Interlayer pattern part
A1 Low power wiring area
A2 High power wiring area
M1 first metal layer
M2 second metal layer
SP laminated pattern
WB wiring board

Claims (5)

In a metal plate laminated wiring board including a wiring pattern, a low power wiring region conductively connected by an interlayer connector, a high power wiring region, and a metal plate laminated at least in the high power wiring region,
The high-power wiring region has a laminated pattern in which an interlayer pattern portion having substantially the same thickness as a surrounding insulating layer is formed on the surface of a reference pattern portion formed with the same thickness as the wiring pattern of the low-power wiring region, The inter-layer pattern portion and the inter-layer connection body in the low-power wiring region include a first metal layer formed by etching, and a second metal layer provided on the side of the reference pattern portion which exhibits resistance during etching of the first metal layer. A metal-plate laminated wiring board, comprising: a metal layer. The metal plate laminated wiring board according to claim 1, wherein the high-power wiring region and the low-power wiring region are conductively connected by the wiring pattern or the laminated pattern. The metal-plate laminated wiring board according to claim 1 or 2, wherein the first metal layer of the interlayer pattern portion is arranged and laminated on the metal plate side. A lamination in which a low-power wiring region in which a wiring pattern is conductively connected by an interlayer connector and an interlayer pattern portion having substantially the same thickness as a surrounding insulating layer are formed on the surface of a reference pattern portion formed with the same thickness as the wiring pattern. A method for manufacturing a metal plate laminated wiring board, comprising a step of laminating and integrating a metal plate at least in a high power wiring area with respect to a wiring board having a high power wiring area having a pattern. The interlayer pattern portion and the interlayer connector in the low-power wiring region include a first metal layer formed by etching, and a second metal layer provided on the reference pattern portion side, which is resistant during etching of the first metal layer. The method for manufacturing a metal-plate laminated wiring board according to claim 4, comprising a metal layer.

Images