JP2003142829A - Multi-layered wiring board and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-layered wiring board and its manufacturing method which can form a conductive connection structure and a heat radiation structure suitably at the same time and sufficiently secure heat radiation. SOLUTION: The multi-layered wiring board has a wiring layer as a lower layer, a protection metal layer 11 provided on the top surface of a wiring pattern part 22 of the wiring layer, a columnar metal body 24a provided on the top surface of the protection metal layer 11, and a wiring layer 27 as an upper layer which is partially and conductively connected to the columnar metal body 24a. Further, the board has a protection metal layer 11 provided on the top surface of a non-pattern or heat-radiation pattern 41 of the lower layer, and a heat-radiation metal body 42 provided on the top surface of the protection metal layer 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer wiring board having two or more wiring layers, a columnar metal body for conductively connecting the layers, and a heat dissipation metal body for dissipating heat between the layers, and a method for manufacturing the same. It is useful as a technique for dissipating heat from mounted components by utilizing the heat dissipation structure of the multilayer wiring board.

[0002]

2. Description of the Related Art In recent years, as electronic devices have become smaller and lighter, electronic components have been made smaller, and there has been an increasing demand for higher density wiring boards for mounting electronic components. . In order to increase the density of the wiring board, a method of increasing the wiring density of the wiring layer itself, a method of forming a multilayer structure by laminating a plurality of wiring layers, and the like are adopted.

In such a multilayer wiring board, it is necessary to make conductive connection between the wiring layers according to the circuit design. As such a conductive connection, a conductive connection structure, which is conventionally called a via hole, is formed by cylindrically plating (through-hole plating) the opening of the insulating layer, and the conductive paste is filled in the opening of the insulating layer. A conductive connection structure, a conductive connection structure in which a metal is deposited by plating in the openings of the insulating layer, and a conductive connection structure in which a columnar metal body is formed by etching prior to forming the insulating layer have been known.

On the other hand, when mounting a semiconductor component or the like on a multilayer wiring board, it is necessary to sufficiently dissipate heat (radiate heat), and with the recent trend toward higher integration and miniaturization of semiconductor components, efficient heat generation is required. The demand for radiation is increasing. As a method of heat dissipation from the mounted parts,
There is also a method of attaching a heat dissipation plate (heat sink), but a method of providing a heat dissipation structure for dissipating heat between layers in the wiring board below the mounting component is also known.

For example, Japanese Unexamined Patent Publication (Kokai) No. 5-218226 discloses a multilayer wiring board having a columnar metal body for conductively connecting the layers and a heat dissipation structure for dissipating heat between the layers.
However, the method of forming the columnar metal body and the heat dissipation structure is not described, and a specific structure or the like cannot be read from the drawings. Further, in a multilayer wiring board having a similar heat dissipation structure, only a method of plating through holes, a method of filling a conductive paste, and a method of depositing a metal by plating have been known.

[0006]

However, in the heat dissipation structure by through-hole plating, the heat transfer area is small, so that the heat transfer property is low, and the heat transfer property is insufficient due to the interposition of the binder even when the conductive paste is used. In addition, although the method of depositing metal by plating is advantageous in terms of heat transfer property of the material, changing the deposition area or the opening density of the plated part changes the deposition rate, so the heat transfer area cannot be increased. There is a problem that heat dissipation becomes insufficient.

Therefore, an object of the present invention is to produce a conductive wiring structure and a heat dissipation structure at the same time, and a method for producing a multilayer wiring board capable of ensuring sufficient heat dissipation, and a method for producing the same. It is to provide a multilayer wiring board.

[0008]

The above object can be achieved by the present invention as described below. That is, the method for manufacturing a multilayer wiring board according to the present invention is the method for manufacturing a multilayer wiring board having a columnar metal body for conductively connecting layers and a heat dissipation metal body for heat dissipation between the layers, wherein the columnar metal body and the heat dissipation metal body are provided. (A) another metal showing resistance during etching of the metal forming the columnar metal body and the heat dissipation metal body,
Forming a protective metal layer by covering substantially the entire surface of the lower wiring layer including the non-patterned portion, (b) forming the columnar metal body and the heat-dissipating metal body on substantially the entire surface of the protective metal layer. A step of forming a metal panel layer, (c) a step of forming a mask layer on a surface portion of the panel layer on which the columnar metal body and the heat dissipation metal body are formed, (d) a step of etching the panel layer And, (e) at least the step of performing etching capable of eroding the protective metal layer to remove at least the protective metal layer covering the non-patterned portion.

In the above, it is preferable that the panel layer is formed in the step (b) by electrolytic plating. That is, it is preferable that the panel layer is a plated layer formed by electrolytic plating.

Further, it is preferable that the pattern portion of the wiring layer covered in the step (a) has a heat radiation pattern portion at a portion where the heat radiation metal body is formed.

On the other hand, the multilayer wiring board of the present invention comprises a lower wiring layer, a protective metal layer provided on the upper surface of the wiring pattern portion of the wiring layer, and a columnar metal body provided on the upper surface of the protective metal layer. And a protective metal layer provided on the upper surface of the non-patterned portion or the heat dissipation pattern portion of the lower wiring layer while having an upper wiring layer partially conductively connected to the columnar metal body, and the protective metal. And a heat dissipation metal body provided on the upper surface of the layer.

A preferred embodiment of the manufacturing method of the present invention is as follows. (1) In the step (a), electroless plating is performed on the entire surface including the non-patterned portion of the lower wiring layer that has been patterned in advance to form a base conductive layer, and then electrolytic plating is further performed on substantially the entire surface. And forming the protective metal layer by means of soft etching of the underlying conductive layer remaining in the non-patterned portion after the etching capable of eroding the protective metal layer in the step (e). To remove.

(2) In the step (a), electroless plating is performed on substantially the entire surface of the insulating layer to form a base conductive layer, and then electrolytic plating is performed on the substantially entire surface of a lower wiring layer patterned. And forming the protective metal layer by means of soft etching of the underlying conductive layer remaining in the non-patterned portion after the etching capable of eroding the protective metal layer in the step (e). To remove.

(3) Prior to the step (a), an insulating layer having substantially the same thickness as the pattern portion of the wiring layer is formed on the non-pattern portion of the lower wiring layer to flatten the surface. Is.

[Operation and Effect] According to the manufacturing method of the present invention,
Since the protective metal layer is provided, a desired columnar metal body and heat dissipation metal body can be formed at the position where the mask layer is formed without eroding the underlying wiring layer during etching of the panel layer. As a result, it is possible to manufacture the multilayer wiring board in which the conductive connection structure and the heat dissipation structure can be formed at the same time, and the heat dissipation can be sufficiently ensured.

When the panel layer is formed by electrolytic plating in the step (b), since the protective metal layer is formed on the entire surface, the plated layer can be formed by electrolytic plating. Since the panel layer is formed after forming the panel layer on substantially the entire surface, not in the holes, the shape and area of the heat dissipation metal body can be freely changed without being affected by the plating current density. Further, the electrolytic plating also provides higher adhesion with the protective metal layer.

Further, when the pattern portion of the wiring layer covered in the step (a) has a heat radiation pattern portion in the portion where the heat radiation metal body is formed, as compared with the case where it does not have the heat radiation pattern portion, it is columnar. The difference between the height of the metal body and the height of the heat dissipation metal body can be reduced, and the flatter surface allows
It is advantageous for the formation process of the upper layer or heat dissipation from the mounted components is more advantageous.

On the other hand, the multilayer wiring board of the present invention can be manufactured by the manufacturing method of the present invention having the above-described effects, and has a highly reliable conductive connection structure and a heat dissipation structure having good heat dissipation. I have.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an example of the multilayer wiring board of the present invention.

As shown in FIG. 1, the multilayer wiring board of the present invention has a lower wiring layer and a wiring pattern portion 22 of the wiring layer.
Of the protective metal layer 11, the columnar metal body 24a provided on the upper surface of the protective metal layer 11, and the upper wiring layer 27 partially conductively connected to the columnar metal body 24a.
And a protective metal layer 11 provided on the upper surface of the non-patterned portion of the lower wiring layer or the heat dissipation pattern portion 41.
And a heat dissipation metal body 42 provided on the upper surface of the protective metal layer 11.

In the present invention, the conductive connection structure and the heat dissipation structure as described above may be provided between at least two arbitrary layers, and the total number of layers may be 2 to several tens or more. is there. In the present embodiment, there are 6 wiring layers in total, and a heat dissipation structure is formed between the first layer and the sixth layer from the top of the drawing, and between the first layer and the third layer and between the fourth layer and the fourth layer. An example in which a conductive connection structure is formed between the sixth layers is shown.

First, a method of forming the columnar metal body 24a will be described. At that time, each step of the manufacturing method of the present invention is appropriately touched. First, as shown in FIG.
The wiring pattern portion 22 of the wiring layer is formed on both surfaces of the above. At that time, the pattern formation method may be any, for example, a method using an etching resist,
It is possible to use one prepared by a method of using a resist for pattern plating. As the base material 21, a base material made of glass fiber and various reaction curable resins such as polyimide resin and epoxy resin can be used. Further, as the metal forming the wiring pattern portion 22 of the wiring layer, copper, nickel, tin or the like is usually used.

Next, as shown in FIG. 2B, electroless plating is performed on the entire surface of the pre-patterned wiring layer including the non-patterned portion to form the underlying conductive layer 10. A plating liquid such as copper, nickel or tin is usually used for electroless plating, but these metals are used for the wiring pattern portion 2 of the wiring layer.
It may be the same as or different from the metal forming 2. Electroless plating solutions are well known for various metals, and various types 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. A plating catalyst such as palladium may be deposited before the electroless plating.

Next, as shown in FIG. 2C, electrolytic plating is performed on the entire surface of the underlying conductive layer 10 in order to cover the entire surface of the lower wiring layer including the non-patterned portion with the protective metal layer 11. The protective metal layer 11 is formed. At this time, as the metal forming the protective metal layer 11, another metal having resistance against etching of the metal forming the columnar metal body is used. Specifically, when the metal forming the columnar metal body is copper, another metal forming the protective metal layer is gold, silver, zinc, palladium, ruthenium, nickel, rhodium, or a lead-tin solder alloy. , Or nickel-gold alloy or the like is used. However, the present invention is not limited to the combination of these metals, and any combination of a metal that can be electrolytically plated and another metal that exhibits resistance during etching can be used.

The above electroplating can be carried out by a known method, but generally, the substrate of FIG. 2 (2) is immersed in a plating bath while the underlying conductive layer 10 is used as a cathode for plating. It is carried out by using a metal ion replenishing source of metal as an anode to deposit metal on the cathode side by an electrolysis reaction.

That is, in the step (a) of the present invention, another metal having resistance to etching of the metal forming the columnar metal body 24a and the heat dissipation metal body 42 is added to the entire surface including the non-patterned portion of the lower wiring layer. Although the protective metal layer 11 is formed by coating the protective metal layer 11 with the base metal, the protective metal layer 11 may be coated with the underlying conductive layer 10 or the like as described above. The protective metal layer 11 may be directly coated without intervening.

In the step (b) of the present invention, as shown in FIG. 3 (4), the metal forming the columnar metal body 24 a and the heat radiating metal body 42 (not shown) are formed on the entire surface of the protective metal layer 11. The panel layer 24 is formed. The panel layer 24 can be formed by electrolytic plating, electroless plating, vapor deposition, reverse sputtering or the like, but it is preferable to perform electrolytic plating for the reasons described above. In this embodiment, an example in which the panel layer 24 is formed by electrolytic plating is shown.

As the metal forming the panel layer 24, copper, nickel or the like is used when electrolytic plating is performed, but it may be the same as or different from the metal forming the wiring layer. Electrolytic plating is performed by the same method as above, but the protective metal layer 11 is used as a cathode. The specific thickness of the panel layer 24 is, for example, 20 to 200 μm.
m or more are exemplified. As described above, in the step (b), since the panel layer 24 is formed on the entire surface by electroplating, the heights of the panel layers 24 are substantially equal, and the columnar metal body 24a and the heat dissipation metal body 42 having a substantially uniform height are quickly formed. Can be formed.

In the step (c) of the present invention, as shown in FIG. 3 (5), the surface of the panel layer 24 on which the columnar metal bodies 24a and the heat radiation metal bodies 42 (not shown) are formed, The mask layer 25 is formed. In the present embodiment, an example in which the mask layer 25 is printed in a dotted pattern by screen printing is shown. The individual size (area or outer diameter) of the mask layer 25 is determined in accordance with the size of the columnar metal body 24a, and for example, one having an outer diameter of 100 to 300 μm or more is exemplified. Thus, in the step (c), since the mask layer 25 is formed in a dotted pattern,
The mask layer 25 can be formed by a simple and inexpensive method such as printing.

In step (d) of the present invention, as shown in FIG. 3 (6), the panel layer 24 is etched.
At that time, if the amount of erosion due to etching is too large, the diameter of the formed columnar metal body 24a may be reduced (the undercut may be increased), which may interfere with the subsequent steps.
If the amount of erosion is too small, the panel layer 24 may remain in the non-patterned portion, causing a short circuit. Therefore, it is preferable that the degree of erosion due to the above-described etching is as shown in FIG.

As a method of etching, the panel layer 24
And according to the type of each metal forming the protective metal layer 11,
An etching method using various etching solutions can be mentioned. For example, when the panel layer 24 (that is, the columnar metal body 24a) is copper and the protective metal layer 11 is the above-mentioned metal (including a metal-based resist), a commercially available alkali etching solution, ammonium persulfate, hydrogen peroxide / sulfuric acid, etc. Is used. According to the above etching, as shown in FIG. 3 (6), the wiring layer (patterned portion and non-patterned portion) covered with the protective metal layer 11, the columnar metal body 24a, and the mask layer 25 remain without being etched. become.

Next, as shown in FIG. 4 (7), the mask layer 25 is removed.
It may be appropriately selected according to the type of the mask layer 25. For example, in the case of a photosensitive ink formed by screen printing, it is removed with a chemical such as alkali.

Next, as shown in FIG. 4 (8), etching is performed so that the protective metal layer 11 can be eroded. As an etching method, there is an etching method using an etching solution different from the step (d). However, when a chloride etching solution is used, both the metal-based resist and copper are eroded, so that another etching solution is used. It is preferably used. Specifically, when the columnar metal body 24a and the heat dissipation metal body 42 and the lower wiring layer are copper and the protective metal layer 11 is the above-mentioned metal, a nitric acid-based material commercially available for solder peeling,
It is preferable to use an acid-based etching solution such as sulfuric acid or cyan. As a result, as shown in FIG. 4 (8),
Only the protective metal layer 11 interposed between the columnar metal body 24a and the wiring layer (pattern portion) can be left. Also,
Only the underlying conductive layer 10 remains in the non-patterned portion.

Next, as shown in FIG. 4 (9), the underlying conductive layer 10 remaining in the non-patterned portion is removed by soft etching. The soft etching is performed by the columnar metal body 2.
This is to prevent excessive erosion of 4a and the exposed wiring layer (pattern portion). Examples of the soft etching method include a method in which an etching solution for the metal forming the underlying conductive layer 10 is used at a low concentration, or is used under mild etching processing conditions.

That is, in the step (e) of the present invention, at least the protective metal layer 11 is etched so that it can be eroded to remove the protective metal layer 11 covering at least the non-patterned portion. When the base conductive layer 10 is provided as described above, the protective metal layer 11 and the base conductive layer 10 are sequentially etched to remove the non-patterned protective metal layer 11 and the base conductive layer 10. As a result, it is possible to reliably prevent the pattern portions from falling.

Next, as shown in FIG. 5 (10), an insulating material 26a for forming the insulating layer 26 is applied. As the insulating material 26a, for example, a liquid curable resin such as a liquid polyimide resin or an epoxy resin, which has a good insulating property and is inexpensive, can be used, and the insulating resin 26a can be made thicker than the height of the columnar metal body 24a by various methods. After coating, it may be cured by heating or light irradiation. As a coating method, various coaters can be used, and a method of hot pressing using a reaction curable resin on the sheet is also possible.

Next, as shown in FIG. 5 (11), the hardened insulating material 26a is ground or polished to form an insulating layer 26 having a thickness substantially the same as the height of the columnar metal body 24a. Examples of the grinding method include a method of 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 the radial direction of the rotary plate. While rotating the hard rotary blade, it was fixedly supported. The top surface can be flattened by moving it along the top surface of the wiring board. Further, as a polishing method, a method of lightly polishing with a belt sander, buffing or the like can be mentioned.

Next, as shown in FIG. 5 (12), an upper wiring layer 27 partially conductively connected to the columnar metal body 24 a.
(Strictly speaking, the wiring pattern portion of the wiring layer) is formed. The wiring layer 27 can be formed by the same method as that for forming the lower wiring layer. For example, the wiring layer 27 having a predetermined pattern can be formed by forming a predetermined mask using a photolithography technique and performing an etching process.

In the present invention, when the conductive connection structure as described above is formed, the heat dissipation metal body 42 is formed in the same process as the columnar metal body 24a to produce the heat dissipation structure. In this embodiment, as shown in FIG. 1, an example is shown in which the pattern portion 22 of the wiring layer covered in the step (a) has the heat radiation pattern portion 41 in the portion where the heat radiation metal body 42 is formed.

First, as shown in FIG. 2A, the one in which the heat radiation pattern portion 41 is formed together with the wiring pattern portion 22 of the wiring layer is prepared. The heat dissipation pattern portion 41 is formed in a portion where the heat dissipation metal body 42 is formed, and it is preferable that the shape and size of the heat dissipation metal body 42 are close to those of the heat dissipation metal body 42 to be formed. In flattening the surface of the multilayer wiring board, in particular, the heat dissipation pattern portion 41 having an outer periphery outside the bottom surface of the heat dissipation metal body 42 to be formed.
Is preferred. Although the heat radiation pattern portion 41 is different in shape and size from the wiring pattern portion 22, it can be similarly formed by changing the shape of the resist.

2 (2) to (3) and FIG. 3 (4) are the same as those of the columnar metal body 24a, but FIG.
In addition to the surface portion forming the columnar metal body 24 a, the mask layer 2 is formed on the surface portion forming the heat dissipation metal body 42.
5 is formed. The shape and size of the mask layer 25 for forming the heat dissipation metal body 42 are determined corresponding to the heat dissipation metal body 42.

In the present invention, the size of the heat dissipation metal body 42 is
The outer diameter of the columnar metal body 24a is about 100 μm, which is smaller than the area of the columnar metal body 24a, to a size of several centimeters square. However, in the example of FIG. 1, the shape is such that the periphery is arranged slightly inside the bottom shape of the package 51 of the semiconductor component 50 to be mounted. As the area of the heat dissipation metal body 42 is larger, the heat transfer area is increased, and the heat dissipation property can be further enhanced. The mask layer 25 can be formed in the same manner except for such a difference in size.

From the etching shown in FIG. 3 (6) to FIG.
The steps up to the flattening of (11) can be performed in the same manner as the columnar metal body 24a. However, in the step of forming the upper wiring layer 27 shown in FIG. 5 (12), the heat dissipation pattern portion 43 is formed in the same manner as the heat dissipation pattern portion 41.

As described above, the conductive connection structure and the heat dissipation structure can be formed between the second layer and the third layer and between the fourth layer and the fifth layer. In the example of FIG. 1, another heat dissipation structure is provided between the third layer and the fourth layer. That is, the heat transfer body 46 that penetrates the base material 21 is provided. Thus, the heat dissipation structure is continuous without being separated by the base material 21, so that a heat dissipation structure penetrating the multilayer wiring board can be obtained. As a result, on the back surface of the mounted component, it is possible to form a heat dissipation surface capable of excellent heat transfer from the front surface.

As the method of forming such a heat transfer body 46, a method of filling a conductive paste, a method of embedding a metal panel in the base material 21, and an opening on the back surface of the base material 21 having a copper foil laminated on one side are formed. Then, electrolytic plating or the like may be performed. Alternatively, a method of forming the insulating layer after forming the heat transfer body 46 on the metal foil by the series of steps described above may be used.

Further, in the example of FIG. 1, the first layer and the second layer,
In addition, the conductive connection structure and the heat dissipation structure are formed between the fifth layer and the sixth layer, which can be performed in the same steps as in the case of the second layer and the third layer.

Further, in the example of FIG. 1, a heat dissipation pattern portion 45 having a considerably larger area than the heat dissipation metal member 44 is formed in the sixth layer, and further heat dissipation fins 47 are formed. The radiating fins 47 can be formed by various joining methods or bonding methods, but can also be formed by the method for forming the columnar metal body 24a as described above. In that case, the protective metal layer 11 is interposed between the heat radiation fins 47. The heat dissipation fins 47 can be formed simultaneously with the formation of bumps for mounting semiconductor components on the outermost layer of the multilayer wiring board.

The shape of the radiation fins 47 may be rib-like or scattered-like, but the larger the total surface area is, the better the heat dissipation becomes, which is preferable. In order to increase the total surface area, it is advantageous to increase the height of the heat radiation fin 47, and in the example of FIG. 1, the height of the heat radiation fin 47 is higher than the thickness of the heat radiation metal body 44. In addition, the radiation fin 47
Therefore, the area of the heat dissipation pattern portion 45 can be reduced when sufficient heat dissipation is obtained.

On the other hand, in the outermost layer (first layer) on the side where the semiconductor component 50 is mounted, a heat radiation pattern portion 45 having substantially the same area as the heat radiation metal body 44 is formed. When mounting the semiconductor component 50, the bottom surface of the semiconductor component 50 and the heat dissipation pattern portion 4
A heat-conducting adhesive tape 60, a heat-conducting adhesive, or the like may be interposed between the first and second electrodes. Alternatively, radiant heat may be transferred without providing anything.

The leads 52 of the semiconductor component 50 are conductively connected to the wiring pattern portion 28 of the first wiring layer by soldering or the like. Each lead 52 is interlayer-connected to the wiring pattern portion 27 of the second wiring layer via the columnar metal body 29 according to the circuit design.

[Another Embodiment] Another embodiment of the present invention will be described below.

(1) The multilayer wiring board of the present invention is not limited to the one shown in FIG. 1, but may be a multilayer wiring board having a structure having a heat dissipation plate 48 inside the board as shown in FIG. 6, for example. The manufacturing method in that case will be described.

First, a substrate 21 having a heat dissipation plate 48 formed on at least one surface thereof is prepared, and a heat dissipation metal body 49 is formed in the same manner as shown in FIG. At this time, when the heat dissipation plate 48 is used as a ground layer or a power supply layer, a columnar metal body for interlayer connection may be simultaneously formed.

From the top of FIG. 6, between the first layer and the second layer, the columnar metal body 24a and the heat radiation metal body 42 are formed in the same manner as shown in FIG. However, in the example of FIG.
Are formed of a large number of columnar bodies. In the present invention, since the heat dissipation metal body 42 is formed by etching, it is possible to form the columnar heat dissipation metal body 42 at a high density.

In this embodiment, the heat dissipation plate 48 can satisfactorily dissipate heat from the semiconductor component 50. In addition, a heat sink may be provided at any position of the multilayer wiring board to directly or indirectly connect to the heat dissipation plate 48. Specifically, for example, there is a method in which a heat sink is provided on the surface of a portion having a circuit allowance and the bottom surface thereof is thermally connected to the heat dissipation plate 48 via a heat dissipation metal body.

(2) The multilayer wiring board of the present invention is not limited to the one shown in FIGS. 1 to 6, but for example, as shown in FIG. 7, the protective metal layer 11 is formed on the upper surface of the non-patterned portion of the lower wiring layer 27. Is provided on the upper surface of the protective metal layer 11, and
A multilayer wiring board having a structure provided with may be used. It is also possible to radiate heat by the heat radiation pattern portion 45 without providing the heat radiation fins 47. The manufacturing method in that case will be described.

That is, the protective metal layer 11 is formed on the exposed surface of the heat dissipation metal body 42 without forming the heat dissipation pattern portion of the second layer.
May be provided. In this case, in the step (b), the panel layer 24
When forming, the height of the portion where the columnar metal body 29 is formed is larger than the height of the portion where the heat dissipation metal body 42 is formed (becomes higher by the amount corresponding to the thickness of the wiring pattern 27). As a result, the height of the heat dissipation metal body 42 obtained is lower than the height of the columnar metal body 29.

In this embodiment, grinding / grinding after formation of the insulating layer is performed.
By polishing the columnar metal body 29 in a large amount by polishing,
The heights of the heat dissipation metal body 42 and the columnar metal body 29 are made uniform. However, in the present embodiment, grinding and polishing after the formation of the insulating layer may be performed according to the height of the columnar metal body 29 so that the insulating layer is thinly formed on the upper surface of the heat dissipation metal body 42. In that case, although the heat dissipation property is slightly lowered due to the interposition of the insulating layer, since the intervening insulating layer is thin, the decrease of the heat dissipation property can be suppressed. The insulating layer remaining on the upper surface of the heat dissipation metal body 42 may be removed by blasting or the like to expose the upper surface of the heat dissipation metal body 42.

On the other hand, the heat dissipation pattern portion 45 of the sixth layer is formed in a plate shape, but the heat dissipation can be further enhanced by forming the pattern into fine irregularities.

(3) The multilayer wiring board of the present invention is not limited to the one shown in FIGS. 1 to 7, but may be a first wiring board as shown in FIG.
A columnar metal body (bump) 30 for mounting the semiconductor component 55 above the wiring pattern portion 28 of the layer and a heat radiation efficiency from the semiconductor component 55 above the heat radiation pattern portion 45 of the first layer are further enhanced. A multilayer wiring board having a structure provided with the heat dissipation metal body 49 may be used. The manufacturing method in that case will be described.

The columnar metal body 30 and the heat radiation metal body 49 described above.
1 is the same as the method of forming the columnar metal body 24a and the heat dissipation metal body 42 in the case shown in FIG. 1, except that the insulating layer 26 is not provided.

Further, in this example, the semiconductor component 5 to be mounted is mounted.
5 is a leadless package, and an electrode 56 is present around the bottom surface thereof. For such a leadless package, the pillar-shaped metal body 3 for mounting as described above is used.
It is advantageous to form 0. The electrode 56 is electrically connected to the columnar metal body 30 via the solder ball 31 and the like.

(4) In the above embodiment, in the step (a), electroless plating is performed on the entire surface including the non-patterned portion of the lower wiring layer that has been patterned in advance to form the underlying conductive layer, and then, Although the example of forming the protective metal layer by performing electrolytic plating on the entire surface has been shown, the entire surface of the insulating layer is subjected to electroless plating to form the underlying conductive layer, and then the patterned lower wiring layer is formed on the entire surface. The protective metal layer may be formed by electrolytic plating. In that case, since the underlying conductive layer is already present, it is possible to form the pattern of the lower wiring layer by pattern plating using electrolytic plating. In addition,
In any of the above methods, the underlying conductive layer is formed by electroless plating, but it may be formed by sputtering or the like.

(5) In the above embodiment, the mask layer is formed by printing, but the mask layer may be formed by using a dry film resist or the like. In that case, thermocompression bonding, exposure, and development of the dry film resist are performed. Further, methylene chloride, sodium hydroxide or the like is used for removing (peeling) the mask layer.

Further, the mask layer may be formed of a metal having resistance against the etching of the panel layer. In that case, the same metal as the protective metal layer can be used, and the mask layer may be formed at a predetermined position by the same method as the pattern formation. When the mask layer is formed of a conductor such as metal, it is possible to form an upper wiring layer that is electrically connected to the columnar metal body without removing it. For example, when an insulating material (such as a thermosetting resin) with a copper foil is hot-pressed while the metal mask layer is left to form an insulating layer, the metal mask layer and the copper foil are conductively connected, and the copper foil is removed. By patterning, a wiring layer can be formed on the upper layer.

(6) In the above-described embodiment, an example in which an insulating layer having a thickness substantially the same as the height of a columnar metal body or the like is formed by grinding or polishing the insulating material has been described. An insulating layer having substantially the same thickness as the height of the columnar metal body may be formed by heating and pressing a certain resin.
In that case, the insulating resin that remains thin on the columnar metal body can be easily removed by plasma treatment or the like, or can be polished and planarized after heating.

(7) In the above-described embodiment, an example is shown in which the mask layer is removed between the steps (d) and (e), but the order of the mask layer removing steps is not limited to this. No
For example, immediately after the protective metal layer etching step, immediately after the underlying conductive layer soft etching step, or the insulating material 2
The mask layer may be removed when 6a is ground or polished.

(8) In the above-described embodiment, an example in which the lower wiring layer having the underlying conductive layer is covered with the protective metal layer has been described. However, the underlying conductive layer is not formed and the protective metal layer is directly coated. May be. In that case, the protective metal layer may be coated on the lower wiring layer by electroless plating or the like, and the protective metal layer that covers the non-patterned portion is removed only by etching capable of eroding the protective metal layer. It is possible to prevent the pattern portions from falling down.

(9) In the above embodiment, an example in which the step (a) is performed is shown in FIG.
As shown in (1 ′), prior to the step (a), the pattern portion 22 of the wiring layer is formed on the non-pattern portion of the lower wiring layer.
The surface may be flattened by forming the insulating layer 29 having substantially the same thickness as the above. In that case, the same material, coating method, curing method, and grinding / polishing method as those used for forming the insulating layer 26 are used.
The insulating layer 29 may be formed. Then, as in the above-described embodiment, the formation of the panel layer 24 is performed (FIG. 9 (4 ′)).
Further, the removal of the underlying conductive layer 10 may be performed (see FIG. 9 (9 ′)).

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a multilayer wiring board of the present invention.

FIG. 2 is a process chart showing an example of a main part of a method for manufacturing a multilayer wiring board according to the present invention.

FIG. 3 is a process chart showing an example of a main part of a method for manufacturing a multilayer wiring board according to the present invention.

FIG. 4 is a process chart showing an example of a main part of a method for manufacturing a multilayer wiring board according to the present invention.

FIG. 5 is a process chart showing an example of a main part of a method for manufacturing a multilayer wiring board according to the present invention.

FIG. 6 is a sectional view showing another example of the multilayer wiring board of the present invention.

FIG. 7 is a sectional view showing another example of the multilayer wiring board of the present invention.

FIG. 8 is a sectional view showing another example of the multilayer wiring board of the present invention.

FIG. 9 is a process drawing showing another example of the main part of the method for manufacturing a multilayer wiring board according to the present invention.

[Explanation of symbols]

11 Protective metal layer 22 Lower layer wiring pattern 24 panel layers 24a Columnar metal body 25 mask layer 27 Upper wiring layer 29 Columnar metal body 30 Columnar metal body (for mounting) 41 Heat dissipation pattern 42 Heat dissipation metal body 43 Heat dissipation pattern section 44 Heat dissipation metal body 45 Heat dissipation pattern section 49 Heat dissipation metal body

Claims (4)

[Claims] 1. A method of manufacturing a multilayer wiring board having a columnar metal body for conductively connecting layers and a heat dissipation metal body for dissipating heat between the layers, wherein the step of forming the columnar metal body and the heat dissipation metal body comprises: Another metal showing resistance during etching of the metal forming the columnar metal body and the heat dissipation metal body,
Forming a protective metal layer by covering substantially the entire surface of the lower wiring layer including the non-patterned portion, (b) forming the columnar metal body and the heat-dissipating metal body on substantially the entire surface of the protective metal layer. A step of forming a metal panel layer, (c) a step of forming a mask layer on a surface portion of the panel layer on which the columnar metal body and the heat dissipation metal body are formed, (d) a step of etching the panel layer And (e) a step of performing etching capable of eroding at least the protective metal layer to remove at least the protective metal layer covering the non-patterned portion, the method for manufacturing a multilayer wiring board. 2. The method for manufacturing a multilayer wiring board according to claim 1, wherein the panel layer is formed in the step (b) by electrolytic plating. 3. The method for manufacturing a multilayer wiring board according to claim 1, wherein the pattern portion of the wiring layer covered in the step (a) has a heat radiation pattern portion in a portion where the heat radiation metal body is formed. 4. A lower wiring layer, a protective metal layer provided on an upper surface of a wiring pattern portion of the wiring layer, a columnar metal body provided on an upper surface of the protective metal layer, and one of the columnar metal bodies. Part has an upper wiring layer conductively connected,
A multilayer wiring board having a protective metal layer provided on the upper surface of the non-patterned portion or the heat radiation pattern portion of the lower wiring layer, and a heat radiation metal body provided on the upper surface of the protective metal layer.