JP3251785B2 - Printed wiring board, manufacturing method of printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates relates to a method of manufacturing a printed wiring board contact and the printed circuit board, method of manufacturing a printed wiring board contact and the printed circuit board relates particularly suitable configuration with an interlayer connection portion.

[0002]

2. Description of the Related Art In a multilayer printed wiring board, electrical connection between wiring pattern layers is made by the following means. That is, after the copper foil stretched on both sides of the insulating substrate is subjected to wiring patterning, the copper foil is laminated and arranged on the wiring patterning surface via an insulating sheet (for example, a prepreg layer), and integrated by heating and pressing. Become In addition,
In manufacturing a printed wiring board, at least one principal surface is generally subjected to a roughening treatment (a blackening treatment, etc.) in consideration of adhesiveness to an insulating material, for example, a resin-based prepreg layer.
Further, a copper foil subjected to an oxide layer forming treatment is used.

[0003] Next, the laminated body is subjected to a drilling process using, for example, a drill or the like, and then the inner wall surface of the hole is metallized by a chemical plating method and further thickened by electroplating to form an inner layer wiring pattern and an outer layer wiring. While making electrical connection between the wiring layers with the pattern, wiring patterning is performed on the surface copper foil to obtain a multilayer printed wiring board. In the case of a multilayer printed wiring board having more wiring layers, it can be manufactured by a method of increasing the number of double-sided printed wiring boards interposed in the middle.

In order to increase the wiring density of a printed wiring board, a system has been developed in which so-called through-hole connection is omitted and interlayer connection is performed under electronic component mounting pads. For example, a hole is formed on a double-sided copper foil-clad substrate with a drill or the like, and the inner wall surface of the hole is formed into a metal layer by a chemical plating method, and is further thickened by electroplating to perform electrical connection between the double-sided copper foils. After that, the hole is filled with an insulating resin, and after curing,
After the resin extruded by polishing is removed and flattened, the entire surface is again subjected to chemical plating and electroplating. Next, a printed wiring board having a configuration in which an interlayer connection is formed below a component mounting pad by patterning a wiring of conductor layers on both surfaces is also known.

Further, in forming the interlayer connection, instead of forming a conductor layer by a plating method, it has been attempted to fill a conductive composition into a hole formed by drilling and cure the same to perform a required interlayer connection. ing.

[0006]

The above-described method of manufacturing a printed wiring board using a plating method for electrical connection between wiring layers has the following disadvantages. That is, in the conventional connection method between the wiring layers, when the wiring pattern (copper foil in which the wiring pattern is formed) is used as the contact surface, there is a problem in connection reliability. That is, since the columnar conductor tip surface forming the interlayer connection portion takes a form in contact with the blackened layer or the oxide layer surface of the wiring pattern, the interlayer connection is likely to have a variation in interface resistance and the like, and as a printed wiring board A problem in the reliability of

In addition, there are the following practical problems. First, in the case where the interlayer connection is performed by a plating method, it is necessary to perform a drilling process (perforation) for electrical connection between wiring layers, a plating process including an inner wall surface of the hole, and the like, to manufacture a printed wiring board. There are disadvantages that the process is redundant and the process management is complicated. Such complicated operation not only leads to an increase in cost, but also causes a problem that fine patterning is impaired because the double-sided conductor layer becomes thicker as a result of repeated plating. On the other hand, a method of embedding a conductive paste in a hole for electrical connection between wiring layers by printing or the like also requires a hole making step as in the case of the plating method. Moreover, it is difficult to uniformly (uniformly) pouring and embedding the conductive paste into the bored holes, and there is a problem in reliability of electrical connection.

In any case, the necessity of the above-described drilling step is reflected in the cost and yield of the printed wiring board, and it is impossible to meet the demand for cost reduction and the like. Accordingly, when the diameter of the perforation hole is relatively small, there are disadvantages such as difficulty in achieving a reliable electrical connection by plating or filling with a conductive paste. In particular, in connection with the copper foil blackening treatment, the problem of interface resistance is greatly highlighted, and there is a problem in reliability.

Further, in the case of a configuration in which a conductor hole for connection between wiring layers is provided on the front and back surfaces of the printed wiring board, wiring cannot be formed and arranged in the region of the conductor hole. Since they cannot be mounted, there is a problem that the improvement of the wiring density is restricted and the improvement of the mounting density of the electronic components is hindered. In other words, the printed wiring board obtained by the conventional manufacturing method cannot sufficiently meet the demands for downsizing the circuit device by high-density wiring and high-density mounting, and furthermore, to reduce the size of electronic devices and the like. There is a need for a more effective method of manufacturing a printed wiring board, including the surface.

[0010] The present invention has been made to address the above circumstances, reliable interlayer connection can be easily configured to be a printed circuit board contact and high-density wiring and mounting, and reliable An object of the present invention is to provide a method for manufacturing a printed wiring board having an interlayer connection.

[0011]

For printed wiring board copper foil Ru used in the present invention In order to achieve the above object, according to at least one principal has oxidation layer, the portion corresponding to the connecting portion between the conductor wiring patterning scheduled region forming Ru and oxide layer is selectively removed.

The preparation process of the present invention in engagement Ru print wiring board is Katachi設a predetermined position of the substrate main surface, and by inserted through the synthetic resin sheet of insulating the thickness direction, the interlayer connection portion A copper foil for a printed wiring board having at least one main surface turned into an oxide layer is superimposed on a wiring element body having protruding conductive bumps through an insulating synthetic resin sheet. And a step of patterning the copper foil for a printed wiring board using the method described above, comprising: printing a region in which the tip side of the protruding conductive bumps is inserted and confronted. An oxide layer on the surface of the copper foil for a wiring board is selectively removed. In addition, the manufacturing method of other printed wiring boards is as follows.
A step of laminating and arranging an insulating synthetic resin-based sheet on the surface of the copper foil for a printed wiring board having at least one main surface formed of an oxide layer; a step of pressing and integrating the laminate; Selective removal of the insulating synthetic resin-based sheet layer
A step of selectively exposing the copper foil surface for a printed wiring board; a step of selectively removing an oxide layer on the exposed copper foil surface for a printed wiring board; and a conductor connected to the surface from which the oxide layer has been removed. you and forming a layer on the selective removal of the synthetic resin sheet layer. The printed wiring board according to the present invention has a
An oxide layer, wherein the oxide layer is selectively removed;
1 and the surface of the copper foil from which the oxide layer has been removed.
The interlayer connection part which is connected by air and the interlayer connection part
Synthetic resin penetrated in the thickness direction and adhered to the copper foil
Base sheet and the first copper foil of the synthetic resin base sheet
The main surface is provided in close contact with the surface on the side different from the
Having an oxide layer, the oxide layer is selectively removed,
The synthetic resin sheet is formed on the surface from which the oxide layer has been selectively removed.
The second interlayer connection portion penetrating through is electrically connected.
And a copper foil.

The above invention has been made based on the following findings. In other words, copper foil for printed wiring boards
In order to increase the adhesion to the insulator layer or to improve the oxidation resistance, the main surface is roughened into an uneven shape, or an oxide layer is formed by forming a zinc layer / chromate (forming an oxide layer). Then, when forming an interlayer connection by a normal through-hole plating method, electrical connection can be secured on the inner wall surface of the hole penetrating in the thickness direction of the copper foil, but in a form in contact with the main surface of the copper foil. When an interlayer connection is formed, there is a problem in reliability due to variations in connection resistance, and the problem of connection resistance can be easily solved by removing the oxide layer on the corresponding copper foil surface. The present invention has been made based on an experimental confirmation that the problem can be solved.

[0014] Printing wiring board copper foil Ru used in the present invention may be prepared in the following manner. That is, an electrolytic copper foil having a thickness of about 4 to 100 nm is prepared in which at least one main surface is roughened, for example, into an uneven shape, or is subjected to a zinc layer / chromate treatment to form an oxide layer (form an oxide layer). I do.
Next, on the oxide layered surface of the electrolytic copper foil, a region corresponding to a wiring pattern to be formed, that is, a region of a planned or designed wiring pattern, and a portion of the oxide layer corresponding to a portion to be connected to a conductor are selectively formed. Obtained by (partial) removal. Then, the selective removal of the oxide layer is performed, for example, by preparing a mold with a pin up, positioning the pin tip against the oxide layer, mechanically pressing the pin tip, and selectively pressing the oxide layer on the pin tip pressing surface. Destroy and remove. Of course, the selective destruction and removal of the oxide layer is not limited to the mechanical means described above, but may be performed by another mechanical method (for example, selective polishing) or a chemical method (for example, selective etching treatment). You can do it too. The selective removal of the oxide layer may be performed not only in a strictly wiring patterning region and in a portion corresponding to a portion to be connected to a conductor, but also in a fine lattice shape, for example. In other words, a mode in which the degree of design freedom of the wiring patterning is provided may be adopted. The copper foil for a printed wiring board is preferably covered with a plating layer of, for example, gold, silver, platinum, palladium, rhodium or the like in order to prevent oxidation of the selectively removed portion.

[0015] In the engaging Ru Manufacturing method according to the present invention, a wiring body having a protruding conductive bump forming an interlayer connections, Katachi設been protruding conductive bump at a predetermined position of the substrate main surface However, it has a configuration in which a synthetic resin sheet is inserted in the thickness direction. Here, examples of the substrate on which the conductive bumps are formed include synthetic resin sheets having good releasability, and conductive sheets (foil). The base is more preferably a single sheet from the viewpoint of workability, but may be patterned in advance, and its shape is not particularly limited.

The conductive bumps can be formed by selective metal plating or the like, but are easily formed by using a conductive composition such as a conductive paste. Such conductive pastes include, for example, silver, gold, copper,
It is prepared by mixing a conductive powder such as a solder powder, an alloy powder thereof or a composite (mixed) metal powder with a binder component such as a polycarbonate resin, a polysulfone resin, a polyester resin, a phenoxy resin, a phenol resin and a polyimide resin. One. In addition, the formation of the projections (for example, conical or columnar bodies) of the conductive bumps by the conductive paste can be achieved by forming a projection having a high aspect ratio by, for example, a printing method using a relatively thick metal mask. The height, diameter,
The distribution is appropriately set according to the configuration of the through-type conductor wiring portion to be formed. Specifically, it is determined in consideration of the arrangement structure of the through-type conductor wiring part to be finally configured,
For example, when the synthetic resin-based sheet is a B-stage epoxy resin layer containing a glass cloth, it is about 80 to 120% of the thickness of the B-stage epoxy resin layer when pressed from both sides, and when pressed from one side. A height of about 180 to 220% of the thickness of the B-stage epoxy resin layer is preferable. The arrangement of the protruding conductive bumps is, for example, 5 mm thick.
At a predetermined position of a stainless steel plate of about mm, a mask having a hole of 0.3 mm is arranged on the entire surface of the housing, and the conductive paste contained in the housing is pressed, and the conductive paste is passed through the hole of the mask. Can be performed by a so-called stamp method having a configuration for pushing out.

The synthetic resin sheet into which the protruding conductive bumps are inserted and which forms the penetrating wiring portion (interlayer connection portion) is, for example, a thermoplastic resin film (sheet). About 25 to 300 μm is preferable. Here, examples of the thermoplastic resin sheet include sheets such as polycarbonate resin, polysulfone resin, thermoplastic polyimide resin, polyethylene tetrafluoride resin, polypropylene hexafluoride resin, and polyether ether ketone resin. The thermosetting resin sheet held in a pre-cured state includes epoxy resin, bismaleimide triazine resin, polyimide resin, phenol resin,
Examples include sheets of polyester resin, melamine resin, or raw rubber such as butadiene rubber, butyl rubber, natural rubber, neoprene rubber, and silicone rubber. These synthetic resins may be used alone or may contain an insulating inorganic or organic filler, and may be a sheet made of glass cloth or mat, organic synthetic fiber cloth or mat, or a sheet combined with a reinforcing material such as paper. There may be.

Further, the wiring element provided with the interlayer connection portion can be formed as follows. That is, the synthetic resin-based sheet main surface is laminated and arranged on the substrate surface on which the protruding conductive bumps are formed, and if necessary on both sides of the laminated body, a metal having a small size and deformation is used as a backing plate. A plate or a heat-resistant resin plate, for example, a stainless steel plate, a brass plate, a polyimide resin plate (sheet), a polytetrafluoroethylene resin plate (sheet) is placed and pressurized, and the protruding conductive bump tip side is made of synthetic resin. It can be formed by penetrating in the thickness direction of the sheet.

[0019] In the above other manufacturing method, an insulating synthetic resin sheet to be stacked on a copper foil for printed wiring board may be used as well those exemplified in the previous SL Manufacturing method.
The pressurization and integration of the laminate may be the same as in the case of manufacturing a normal copper foil-clad substrate, and the selective removal of the insulating synthetic resin-based sheet layer may be performed by a machine such as drilling. This is performed by chemical means such as a physical means and a photo etching method. Further, the selective removal of the oxidized layer on the exposed copper foil surface of the printed wiring board can be achieved by mechanical destruction or removal such as pressing or polishing, or etching using a synthetic resin-based sheet layer as a mask. No. Means for forming a conductor layer connected to the surface from which the oxide layer has been removed in the selectively removed portion of the synthetic resin-based sheet layer include, for example, a chemical plating method, a combination of a chemical plating method and an electroplating method, or a conductive layer. Implantation of the body and the like.

[0020]

[Action] for printed wiring board copper foil Ru used in the present invention, oxide layer of the interface region surface of the conductor forming the interlayer connection are exposed metal surface is pre-selectively removed. Therefore, even when the tip surface of the interlayer connection (conductor) in which the insulator layer is inserted in the thickness direction is in contact with the copper foil surface, and a so-called surface contact type electrical connection portion is formed, good electrical connection is obtained. It is easily formed. In other words, the problem of interface resistance is greatly improved,
A highly reliable interlayer connection can be formed. On the other hand, the oxide layer on the surface of the region other than the region from which the oxide layer has been selectively removed exhibits good adhesion to the insulating resin-based sheet layer that forms a laminate with each other. Therefore, the printed wiring board functions as a printed wiring board that is not likely to be peeled or damaged, for example, in a heat / cool cycle.

According to the manufacturing method of the engaging Ru printed wiring board of the present invention, the interlayer connection portion for electrically connecting the wiring layers, and the like plastic state of the synthetic resin sheet forming the interlayer insulating layer, the supporting base By press-fitting a conductive bump with a sharp tip on the body surface,
A reliable electrical connection between the wiring layers is reliably achieved. In other words, since the conductive bumps are in contact with the copper foil surface from which the oxide layer has been removed while simplifying the process, such as omitting the step of drilling holes for interlayer connection, a highly reliable electrical connection is formed. I can do it. More specifically, connection between fine wiring pattern layers can be achieved with high accuracy and high reliability based on the action of the copper foil for a printed wiring board. Also,
Since there is no need to form connection holes in the electrical connection between the wiring pattern layers, a printed wiring board capable of high-density wiring and high-density mounting can be manufactured at a low cost.

According to the other method for manufacturing a printed wiring board,
As with the previous SL Manufacturing method, the distal end surface of the conductor forming the interlayer connection, since contact against the copper foil surface that is removing the oxide layer, to form a reliable electrical connection.

[0023]

【Example】

Example 1 FIGS. 1A and 1B schematically show an embodiment of this example.

First, a 35 μm-thick electrolytic copper foil (trade name: EC-3, manufactured by Mitsui Mining & Smelting KK) 1 having a chromate coating layer formed on one principal surface is prepared. Figure 1
As shown in cross section in (a), dry film type photoresists 2 and 2 'were laminated respectively. Next, the photoresist 2 on one main surface side on which the chromate coating layer is formed is selectively exposed through a negative mask and developed, and as shown in cross section in FIG. The electrodeposited copper foil surface 1 in the region to be formed was exposed 3.
Thereafter, one surface of the electrolytic copper foil was subjected to an etching treatment using a 5% hydrochloric acid aqueous solution as an etching solution to selectively remove the three exposed chromate coating layers. In the selective removal of the chromate coating layer, the lower copper foil surface was also thinly removed to expose a new surface. Next, the photoresists 2 and 2 'are respectively peeled and removed by treating with an alkaline aqueous solution, and an oxide layer in a region where wiring patterning is to be performed and a portion corresponding to a portion to be connected to a conductor is selectively removed. Thus, a copper foil for a printed wiring board was obtained.

Embodiment 2 FIGS. 2A to 2D schematically show an embodiment of this embodiment.

While preparing the copper foil 4 for a printed wiring board obtained in Example 1, a hole having a diameter of 0.3 mm was formed at a position corresponding to the selectively exposed new surface of the copper foil 4 for a printed wiring board. Prepared metal screen. Then, a metal screen was positioned and arranged on the four surfaces of the copper foil for a printed wiring board, and a conductive paste containing silver powder as a main component and a lower epoxy resin binder was printed. Then, after pre-drying at 70 ° C, the metal screen is positioned at the same position.
Place, print conductive paste, pre-dry at 70 ℃ 3
Repeated floor, height 200, as shown in cross section in Figure 2 (a)
After forming a conical conductive bump 5 having a diameter of about μm, the conductive bump 5 was further cured by heating at 180 ° C.

Next, as shown in cross section in FIG. 2B, a glass epoxy-based prepreg (trade name: TLP-551) having a glass cloth thickness of 100 μm is formed on the surface of the copper foil 4 for a printed wiring board on which the conductive bumps 5 are formed. (Manufactured by Toshiba Chemical KK) 6 were aligned and laminated and pressed (pressed) through an elastic body such as a silicone rubber layer while being heated to 90 ° C. By this pressing (pressing), a laminated body is obtained in which the tip of the conductive bump 5 penetrates the glass epoxy prepreg layer 6 and the copper foil 4 for a printed wiring board and the glass epoxy prepreg layer 6 are in close contact. Was.

The printed wiring board copper foil 4 ′ prepared in Example 1 prepared separately was aligned and laminated on the exposed surface of the conductive bump 5 at the tip end of the conductive body 5 through which the glass epoxy prepreg layer 6 of the laminate was inserted. , Using a vacuum-type heating and pressing press, 170
It pressed at 40 degreeC and 40 kg / cm < ² > (resin pressure). By this press working, a double-sided copper foil 4,4'-clad laminate as shown in cross section in FIG. 2 (c) was obtained. That is, the surfaces of the double-sided copper foils 4 and 4 'which are electrically connected at the interlayer connection portion 5' penetrating the insulator layer 6 'formed of the glass epoxy prepreg layer 6 and correspond to the interlayer connection portion 5'. However, a double-sided copper foil 4, 4'-clad laminate having a configuration in which the oxide layer was selectively removed was prepared. Thereafter, a so-called photo-etching treatment is applied to the double-sided copper foils 4, 4 'of the double-sided copper-clad laminate,
A double-sided wiring board as shown in cross section in FIG. 2 (d) was obtained.

The conventional double-sided wiring board was subjected to various conventional tests and evaluations.
10 mΩ, bath controlled by silicone oil, 260
° C, 5sec. ~ Room temperature, 10sec. In the hot oil test, the resistance change after 100 cycles was within 5%. In the manufacturing process of the double-sided wiring board, the adhesion strength between the double-sided copper foils 4 and 4 ′ of the prepared laminated board was measured in the form of a peel strength measurement pattern, showing a strength of 1.8 kg / cm. Even after accelerated deterioration test at 240 ℃ for 240h
It showed a strength of 1.2 kg / cm.

For the purpose of comparison, when the double-sided copper foil 4,4'-clad laminate was prepared, the oxide layer of the copper foil 4,4 'for the printed wiring board was not selectively removed (Comparative Example 1). The resistance per via is 20-40 mΩ, in hot oil test
The resistance change after 100 cycles increased to 150%.
When the oxide layers of the copper foils 4 and 4 'for the printed wiring board were completely removed (Comparative Example 2), the peel strength measurement showed a strength of 1.5 kg / cm, but the accelerated aging test at 155 ° C for 240 hours. Later, it was reduced to 0.25 kg / cm.

Embodiment 3 FIGS. 3 (a) to 3 (i) and FIGS. 4 (a) to 4 (d) schematically show an embodiment of this embodiment.

First, a 35 μm-thick electrolytic copper foil (trade name: EC-A3) having a chromate coating layer formed on both surfaces, 1, 1 ',
Epoxy resin sheet (Product name: AS-3000, Hitachi Chemical KK
7), electrolytic copper foils 1 and 1 ′ are thermocompression-bonded and cured on both surfaces of the epoxy resin sheet 7, respectively, as shown in FIG.
A double-sided copper foil-clad board as shown in FIG. Next, on both copper foil 1, 1 'surfaces of the double-sided copper foil-clad board, FIG.
As shown in cross section in (b), dry film type photoresists 2 and 2 'were laminated, and one of the two photoresists was exposed through a negative mask. Thereafter, a developing process is performed to selectively remove the photoresist 2 in a region where an interlayer connection portion is to be formed, and as shown in a sectional view in FIG. 3C, the chromate film layer of the electrolytic copper foil 1 is selectively removed. Exposed.

Next, the exposed area of the chromate film layer of the electrolytic copper foil 1 is selectively removed by etching to form a hole in the electrolytic copper foil 1 as shown in FIG. The surface of the base epoxy resin sheet 7 was selectively exposed. Thereafter, the photoresist 2, using an aqueous alkali solution,
After stripping and removing 2 '(FIG. 3 (e)), the exposed epoxy resin-based sheet 7 is selectively oxidized by etching with potassium permanganate aqueous solution heated to 70 ° C. By disassembling, as shown in cross section in FIG. 3 (f), the opposing electrolytic copper foil 1 'surface was selectively exposed. The selectively exposed surface of the electrolytic copper foil 1 'was treated with an aqueous alkali solution containing sodium hypochlorite as a main component, and the exposed surface of the electrolytic copper foil 1' was blackened (roughened). Then, it is treated with a 10% aqueous solution of hydrochloric acid to reduce the blackened surface to expose the rough surface of copper,
A platinum layer 8 having a thickness of 0.1 μm was formed on the exposed rough surface by a chemical plating method (FIG. 3 (g)).

Next, by performing conventional treatments such as catalyst application, chemical copper plating, and electrolytic copper plating, the entire surface of the electrolytic copper foils 1, 1 'including the platinum layer 8 surface is applied by conventional means.
As shown in cross section in FIG. 3 (h), copper plating layers 9 and 9 'each having a thickness of 20 μm were applied to form a double-sided copper foil-clad board having an interlayer connection 10. Dry film-type photoresists 2 and 2 'were laminated again on both sides of the double-sided copper foil-clad board provided with the interlayer connection 10 prepared above, and one of the two photoresists was exposed through a negative mask. Thereafter, after performing a development process and patterning the etching resist, the copper plating layer 9 and the electrolytic copper foil 1 are selectively etched and then the photoresists 2 and 2 'are peeled and removed. ) To obtain a single-sided wiring pattern substrate as shown in cross section.

On the other hand, a core substrate 11 on which wiring patterning 11b is provided on both sides of a glass-epoxy resin based insulating substrate 11a having a thickness of 0.6 mm is prepared, and as shown in cross section in FIG. The single-sided wiring pattern substrate was positioned and laminated on both sides of the substrate via glass / epoxy resin prepregs each having a thickness of 100 μm. Then, the laminated body arranged in this manner is set in a vacuum-type heating / pressing machine, and is pressed and heated at 170 ° C. and 40 kg / cm ² (resin pressure) to form a cross section as shown in FIG. As shown, a six-layer double-sided copper foil-clad board was obtained.

Next, the above-mentioned six-layer double-sided copper foil-clad board is drilled, and a hole penetrating between both sides at a predetermined position.
After forming No. 12, a so-called through-hole plating treatment was performed to obtain a six-layer double-sided copper foil-clad board having a through-hole connection as shown in cross section in FIG. 4 (c). Thereafter, a required patterning process is performed on the copper foils 1 ′ on both sides by a conventional means, and as shown in a sectional view in FIG.
A 6-layer double-sided copper foil clad board having a surface layer IVH (interstitial via hole) was obtained. In the printed wiring board thus manufactured, the inside of the interlayer connection 10 (via) provided in the single-sided wiring pattern board (see FIG. 3 (i)) is also filled with epoxy resin. It was possible to form a pad.

The conventional six-layer double-sided wiring board was subjected to various conventional tests and evaluations.
5-10 mΩ, bath controlled by silicone oil, 2
60 ° C, 5sec. ~ Room temperature, 10sec. In the hot oil test, the resistance change after 100 cycles was within 5%.
Further, in the manufacturing process of the six-layer double-sided wiring board, the adhesion strength of the double-sided copper foils 4, 4 'of the single-sided wiring pattern substrate thus prepared was measured in the form of a peel strength measurement pattern.
It showed a strength of 1.8 kg / cm and a strength of 1.2 kg / cm even after the accelerated aging test at 155 ° C for 240 hours.

It should be noted that the present invention is not limited to the above-described embodiment, but can be implemented in various modifications without departing from the spirit of the invention.

[0039]

According to the present invention, a printed wiring not only can easily and reliably secure a stable electrical connection between wiring pattern layers, but also has good adhesion or integrity to an insulator. Boards can be provided. That is,
It is possible to form and maintain a highly reliable interlayer connection, and to provide a highly reliable printed wiring board with a small decrease in pill strength even in an accelerated deterioration test with high yield.

[Brief description of the drawings]

[1] The manufacturing method of a printing wiring copper foil Ru used in the present invention shows schematically, (a) shows the cross-sectional view showing a state of arranging the photoresist layer to copper foil surface, (a) shows the Sectional drawing which shows the state which patterned the photoresist layer.

FIG. 2 schematically shows an embodiment of a method for manufacturing a printed wiring board according to the present invention, in which (a) is a cross-sectional view showing a state in which protruding conductive bumps are provided on a copper foil surface; (b) is a cross-sectional view showing a state in which a synthetic resin sheet is disposed on a copper foil surface provided with protruding conductive bumps, and (c) is electrically connected to the tip of the conductive bump through which the synthetic resin sheet is inserted. FIG. 4D is a cross-sectional view showing a state where the copper foil is integrated with the copper foil, and FIG. 4D is a cross-sectional view showing a state where the copper foil on both sides is patterned.

[3] Another embodiment of the manufacturing method of the printed wiring board shows schematically, (a) shows the cross-sectional view showing a state in which laminated a copper foil on both surfaces of the insulating layer, (b) is Sectional view showing a state where a photoresist layer is arranged on a copper foil surface, (c) is a sectional view showing a state where one photoresist layer is patterned, (d)
Is a cross-sectional view showing the etched state of one copper foil surface, (e)
Is a cross-sectional view showing a state in which the photoresist layers on both sides are peeled and removed, (f) is a cross-sectional view showing a state in which the insulator layer is selectively removed using a patterned copper foil as a mask, and (g) is a cross-sectional view showing the insulator layer. Sectional view showing a state in which a platinum layer is formed by plating on the surface exposed by selective removal, (h) is a sectional view showing a state in which a copper plating layer is formed on both sides, and (i) is a state in which single-sided wiring is patterned. FIG.

FIGS. 4A and 4B schematically show an embodiment of a method for manufacturing a multilayer printed wiring board using the single-sided wiring pattern board shown in FIG. 3I, wherein FIG. Cross-sectional view showing a state of being stacked on a single-sided wiring pattern board, (b)
FIG. 3 is a cross-sectional view showing a state in which heating and pressurization and integration are performed, (c) is a cross-sectional view showing a state in which a through-hole conductor layer is provided, and (d) is a cross-sectional view showing a state in which both sides are patterned.

[Explanation of symbols]

1,1 ': electrolytic copper foil with oxide layer 2, 2': photoresist layer 3: exposed surface of electrolytic copper foil 4, 4 ': copper foil for printed wiring 5: conductive bump 5', 10 ... Interlayer connection 6 ... Synthetic resin sheet (prepreg layer)
7: Epoxy resin sheet 8: Platinum layer
9 Copper plating layer 11 Core wiring board
11a …… Insulating substrate 11b …… Wiring pattern

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI H05K3 / 46 H05K3 / 46N (56) References JP-A-2-111097 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) H05K 1/05 H05K 1/09 H05K 3/06 H05K 3/40 H05K 3/46

Claims (2)

(57) [Claims] 1. A wiring element having a projecting conductive bump formed at a predetermined position on a main surface of a substrate and penetrating an insulating synthetic resin sheet in a thickness direction to form an interlayer connection portion. the body, via a synthetic resin sheet of the insulation, superimposed at least one main surface oxide layer of print wiring board copper foil, pressing, a step of integrating, for copper the printed circuit board a method of manufacturing a printed wiring board and a step of wiring patterning foil, selective oxidation layer of the printed wiring board copper foil surface of the distal end side of the protruding conductive bump is in contact Nuki挿-pair region A method for manufacturing a printed wiring board, wherein the printed wiring board is removed. 2. An oxide layer is provided on a main surface, and this oxide layer is selected.
Electrically connected to the first copper foil that has been electrically removed and the surface of the copper foil from which the oxide layer has been removed.
And the copper foil penetrated in the thickness direction by the interlayer connection portion
And a surface of the synthetic resin sheet that is in close contact with the first copper foil.
Are provided in close contact with different surfaces and have an oxide layer on the main surface.
Then, the oxide layer is selectively removed, and the selective oxidation is performed.
Before penetrating the synthetic resin sheet on the surface from which the layer has been removed
Includes serial interlayer connection portion and a second copper foil are electrically connected
A printed wiring board characterized in that: