JP2000357762A - Package board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package board, in which a plane layer can fully fulfill its function. SOLUTION: A planar layer 21 which forms a power-supply layer is arranged on the surface of a board. An electrical resistance up to the plane layer 21 from an external board (e.g. a daughter board) is lowered. Thereby, electric power is supplied easily from the side of the daughter board, and the planer layer 21 which constitutes the power-supply layer fulfills its function fully.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin package substrate to which conductive connection pins are fixed.

[0002]

2. Description of the Related Art In recent years, a package substrate for connecting an IC chip or the like to a motherboard or a daughter board has been required to have a low dielectric constant and a low dielectric loss tangent with an increase in the frequency of signals. Therefore, the mainstream of the material of the substrate is shifting from ceramic to resin.

Under such a background, as a technique relating to a printed wiring board using a resin substrate, for example, Japanese Patent Publication No.
No. 55555 discloses that an epoxy acrylate is formed as an interlayer resin insulating layer on a glass epoxy substrate on which a circuit is formed, a via hole opening is formed by using a photolithography method, and the surface is roughened. A so-called build-up multilayer wiring board in which a resist is provided and a conductive circuit and a via hole are formed by plating has been proposed.

[0004] In a build-up multilayer wiring board used as a package substrate, a plane layer constituting a power supply layer so that a large amount of power can be instantaneously supplied to an IC chip, and a plane layer constituting an earth layer for the purpose of noise reduction. Are arranged.

[0005]

However, in the structure described above, the plane layer is connected to a pad for connection to an external substrate (for example, a daughter board) through a via hole. Since a current flows from the daughter board side through the fine via hole, the plane layer constituting the power supply layer is limited in the power that can be sent to the IC chip, and cannot perform a sufficient function. Also, the plane layer constituting the ground layer is not connected to the ground line on the daughter board side via a fine via hole having a high resistance, so that it cannot sufficiently play the role of preventing noise.

In order to connect a multilayer printed wiring board used as a package substrate to a daughter board, it is necessary to attach conductive connection pins to pads provided on the multilayer printed wiring board. However, even when a metal pad is provided on a package substrate made of a resin, the bonding strength between the two is low, and when a stress is applied to the conductive connection pin, the conductive connection pin sometimes peels off together with the pad.

The inventions of claims 1, 2, and 3 have been proposed to solve such problems, and an object of the invention is to provide a package substrate in which a plane layer can sufficiently fulfill a function. I do.

[0008] The invention of claims 4, 5, 6, 7, 8, 9 is
It has been proposed to solve such a problem, and an object of the present invention is to provide a resin package substrate in which a plane layer can sufficiently perform a function and conductive connection pins are not easily separated.

[0009]

Means for Solving the Problems As a result of intensive studies, the present inventors have reached the present invention. That is, a plane layer, which is a conductor layer, is arranged on the surface of the substrate, and the conductive connection pins are directly connected to the plane layer, thereby reducing the electric resistance from the external substrate (eg, daughter board) to the plane layer.
This facilitates power supply from the daughter board side, and causes the plane layer constituting the power supply layer to perform a sufficient function. Also, the plane layer constituting the ground layer is connected to the ground line on the daughter board side through the low-resistance conductive connection pin to sufficiently play the role of noise prevention. Note that the plane layer may be in a mesh shape. The mesh is formed by arranging square and circular conductor-free portions (see FIG. 12).

Further, according to the present invention, the pad to which the conductive connection pin is fixed is covered with the organic resin insulating layer provided with an opening for partially exposing the pad. Therefore, when the package substrate is attached to another substrate such as a motherboard via the conductive connection pins, for example, there is a displacement between the conductive connection pins and the socket of the motherboard, and the conductive connection pins are stressed. The pad is held down by the organic resin insulating layer even when the substrate is warped due to the heat history of the heat cycle conditions, and the peeling from the substrate can be prevented. In particular, even when it is difficult to obtain a sufficient adhesive strength by bonding completely different materials such as a metal pad and an interlayer resin insulating layer, high peel strength can be imparted by covering the pad surface with the organic resin insulating layer. .

According to the fifth aspect of the present invention, the conductive connection pin is made of at least one metal selected from the group consisting of copper or copper alloy, tin, zinc, aluminum, and noble metal having excellent flexibility. When the stress is applied, the conductive connection pin bends and absorbs the stress, which makes it difficult for the conductive connection pin to peel off from the substrate. Phosphor bronze is suitable as the copper alloy used for the conductive connection pins. This is because, in addition to being excellent in flexibility, it has excellent electrical characteristics and also has excellent workability into conductive connection pins.

As the conductive connection pin, a so-called T-shaped pin composed of a plate-shaped fixing portion and a column-shaped connecting portion protruding substantially at the center of the plate-shaped fixing portion is preferably used. The plate-shaped fixing portion is a portion fixed to the conductor layer serving as a pad via a conductive adhesive, and is appropriately formed in a circular shape or a polygonal shape according to the size of the pad. The shape of the connecting portion is not particularly limited as long as it can be inserted into another substrate, and may be any shape such as a cylinder, a prism, a cone, or a pyramid. This connection is basically one for the pin in the normal position,
There is no particular problem even if two or more are provided, and they may be formed as appropriate according to the other substrate to be mounted.

In the conductive connecting pin, the columnar connecting portion has a diameter of 0.1 to 0.8 mm and a length of 1.0 to 10 m.
m, the diameter of the plate-shaped fixing portion is desirably in the range of 0.5 to 2.0 mm, and is appropriately selected depending on the size of the pad, the type of other substrate to be mounted, and the like.

According to the sixth aspect of the present invention, since the columnar connecting portion of the conductive connecting pin is provided with a constricted portion smaller than the diameter of the other portion, the pin is easily bent.
Therefore, when stress is applied to the conductive connection pin, the connection portion is bent at the constricted portion, so that the stress is absorbed, and the conductive connection pin is hardly peeled off from the substrate.

As the conductive connection pin, a so-called T-shaped pin composed of a plate-shaped fixing portion and a column-shaped connecting portion protruding substantially at the center of the plate-shaped fixing portion is preferably used. The plate-shaped fixing portion is a portion fixed to the conductor layer serving as a pad via a conductive adhesive, and is appropriately formed in a circular shape or a polygonal shape according to the size of the pad. Further, the connection portion is a portion to be attached to another substrate, and there is no particular problem in the shape as long as it can be inserted into the electronic component.
Anything such as a prism, a cone, or a pyramid may be used. Usually, this connection portion is basically one for one pin, but there is no particular problem if two or more connection portions are provided, and the connection portion may be appropriately formed according to another board to be mounted.

The conductive connecting pin has a plate-shaped fixing portion having a diameter of 0.5 to 2.0 mm, a columnar connecting portion having a diameter of 0.1 to 0.8 mm, and a length of 1 to 10 mm. It is preferable to select the type according to the type of the package substrate to be fixed or the other substrate to be mounted.

The constricted portion is provided in the middle of the connecting portion, and is formed thinner than other portions. The thickness of the constricted portion varies depending on the material of the conductive connection pin, the size of the conductive connection pin, and the like.
It is important that the diameter be 50% or more and 98% or less of the diameter of the connection part itself. The diameter of the constricted part is 5 times the diameter of the other part
If it is less than 0%, the strength of the connection portion becomes insufficient, and the package may be deformed or broken when the package substrate is mounted. Also, the diameter of the constricted part is 98 times the diameter of the other part.
%, The desired flexibility cannot be imparted to the connection portion, and the effect of absorbing stress cannot be obtained. Note that a plurality of constrictions may be formed.

The material constituting the conductive connection pin of the present invention is not particularly limited as long as it is a metal, and is formed of at least one kind of metal from among gold, silver, copper, nickel, cobalt, tin and lead. Good to do. Iron alloy, trade name "Kovar" (an alloy of Ni-Co-Fe), stainless steel, and phosphor bronze which is a copper alloy are preferable materials. This is because the electrical characteristics are good and the processability of the conductive connection pin is excellent. In particular, phosphor bronze has high flexibility and is therefore suitable for absorbing stress.

According to the seventh aspect of the present invention, since the melting point of the conductive adhesive is 180 to 280 ° C., the bonding strength with the conductive connecting pin of 2.0 kg / pin or more is ensured. This strength can be measured after reliability tests such as heat cycle, or
Even after applying the heat required for mounting the IC chip, the strength of the IC chip does not decrease much. When the temperature is lower than 180 ° C., the adhesive strength is also around 2.0 kg / pin.
Only about 5Kg / pin comes out. In addition, the heating of the IC chip mounting dissolves the conductive adhesive, causing the conductive connection pins to drop or tilt. If it exceeds 280 ° C., the resin insulating layer and the solder resist layer, which are resin layers, will melt at the melting temperature of the conductive adhesive. In particular, a desirable temperature is 200-260 ° C.
This is because the conductive adhesive at that temperature reduces the variation in the bonding strength of the conductive connection pins, and the heat actually applied thereto does not damage the resin layer constituting the package substrate.

According to the invention of claim 8, the conductive adhesive is formed of at least one kind of tin, lead, antimony, silver, gold and copper. Can be formed. In particular, the conductive adhesive containing at least tin-lead or tin-antimony can form the above-mentioned melting point range, and is easily fixed again even if melted by heat, so that the conductive connecting pin is Does not cause falling off or tilting.

The conductive adhesive is Sn / Pb, Sn / Pb.
Due to the alloys of Sb, Sn / Ag, and Sn / Sb / Pb, especially, the adhesive strength is 2.0 Kg / pin, the variation is small, and even under the heat cycle condition or the heat of mounting the IC chip, There is no decrease in the adhesive strength of the conductive connection pin, no drop-out or inclination of the pin, and electrical connection is ensured.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a package substrate according to a first embodiment will be described with reference to FIGS. 1 to 8 together with a method for manufacturing a build-up substrate. The following method is based on the semi-additive method, but may use the full-additive method.

[First Embodiment] (1) First, a core substrate having a conductor layer formed on the surface of the substrate is prepared. As a core substrate, a glass epoxy substrate,
A copper-clad laminate in which copper foils 8 are stuck on both sides of a resin insulating substrate such as a polyimide substrate or a bismaleimide-triazine resin substrate can be used (see FIG. 1A). Copper foil 8
Has a roughened surface (mat surface) on one side and is firmly adhered to the resin substrate. After a through hole is formed in this substrate by a drill, electroless plating is performed to form a through hole 9. Copper plating is preferred as the electroless plating. Subsequently, a plating resist is formed and an etching process is performed to form the conductor layer 4. Electroplating may be further performed for thickening the copper foil. Copper plating is also preferred for this electroplating. Further, after the electroplating, the surface of the conductor layer 4 and the inner wall surface of the through hole 9 may be made rough surfaces 4a, 9a (see FIG. 1B).

Examples of the roughening treatment include, for example, blackening (oxidation) -reduction treatment, spray treatment with a mixed aqueous solution of an organic acid and a cupric complex, treatment with Cu-Ni-P needle-like alloy plating, and the like. Is mentioned.

Next, the obtained substrate is washed with water and dried. Thereafter, a resin filler 10 is filled between the conductor layers 4 on the substrate surface and in the through holes 9 and dried (FIG. 1).
(C)). Subsequently, unnecessary resin filler 10 on both sides of the substrate
Is ground by belt sander polishing or the like to expose the conductor layer 4 and the resin filler 10 is fully cured. The substrate is smoothed by filling the recesses between the conductor layers 4 and the through holes 9 (see FIG. 1D).

Next, the roughened layer 1 is formed on the exposed surface of the conductor layer 4.
1 is provided again (see FIG. 2A). In addition, FIG.
The part indicated by the circle in the middle is the conductor layer 4 on which the roughened layer 11 is provided.
Is enlarged. The roughened layer 11 is desirably formed of the needle-like or porous alloy layer of Cu-Ni-P as described above. A roughened layer can be formed by an etching process. In the case of using a Cu-Ni-P needle-like or porous alloy layer, it is preferable to perform the etching under the trade name "Interplate" manufactured by Ebara Uzilite and the etching processing under the trade name "MEC etch Bond" manufactured by MEC.

(2) A resin insulating layer 2 composed of resin layers 2a and 2b is formed on both surfaces of the wiring board having the conductor layer 4 prepared in (1) (see FIG. 2B). This resin insulating layer 2 functions as an interlayer resin insulating layer 200 of the package substrate as described later. Examples of a material constituting the resin insulator layer (hereinafter, interlayer resin insulation layer 200) include, for example,
A thermosetting resin, a thermoplastic resin, or a composite resin thereof may be used. It is desirable to use an adhesive for electroless plating as the interlayer resin insulating layer 2. The most suitable adhesive for electroless plating is one in which heat-resistant resin particles soluble in a cured acid or oxidizing agent are dispersed in an uncured heat-resistant resin hardly soluble in an acid or oxidizing agent. is there.
This is because, as described later, by treating with a solution of an acid and an oxidizing agent, the heat-resistant resin particles are dissolved and removed, and a roughened surface composed of an octopus pot-shaped anchor can be formed on the surface.

In the above-mentioned adhesive for electroless plating, particularly as the heat-resistant resin particles subjected to the curing treatment, a heat-resistant resin powder having an average particle diameter of 10 μm or less, a particle having a relatively large average particle diameter, and an average particle diameter However, particles obtained by mixing relatively small particles are desirable. Because they can form more complex anchors.

Examples of the heat-resistant resin that can be used include, for example,
Epoxy resins (bis-A type epoxy resin, cresol novolak type epoxy resin, etc.), polyimide resins, composites of epoxy resins and thermoplastic resins, and the like are included. As the thermoplastic resin to be composited, polyether sulfone (PES), polysulfone (PSF), polyphenylene sulfone (PPS), polyphenylene sulfide (PPES), polyphenyl ether (PPE), polyetherimide (PI), and the like can be used. Examples of the heat-resistant resin particles soluble in a solution of an acid or an oxidizing agent include, for example, an epoxy resin (especially an epoxy resin cured with an amine-based curing agent), an amino resin, a polyethylene-based rubber, a polybutane-based rubber, Rubbers such as polybutadiene rubber and polybutyne rubber are exemplified. The interlayer insulating layer is formed by applying a resin film and applying heat and pressure to the resin film.

(3) Next, an opening 6 for forming a via hole for securing electrical connection with the conductor layer 4 is provided in the interlayer resin insulating layer 2 (see FIG. 2C). When the above-mentioned adhesive for electroless plating is used, an opening 6 is provided by placing a photomask on which a circular pattern for forming a via hole is drawn, exposing and developing, and then thermosetting. On the other hand, when a thermosetting resin is used, an opening 6 for a via hole is provided in the interlayer resin insulating layer 2 by performing laser processing after thermosetting. When a resin film is attached to form an interlayer insulating layer, an opening for a via hole is provided by processing with a laser such as carbonic acid, YAG, excimer, or UV laser. If necessary, desmearing is performed by dipping with permanganic acid or the like or dry etching with plasma or the like.

(4) Next, an opening 6 for forming a via hole
The surface of the interlayer resin insulation layer 2 provided with the surface is roughened (FIG. 2).
(D)). When an adhesive for electroless plating is used for the interlayer resin insulating layer 2, heat-resistant resin particles present on the surface of the adhesive layer for electroless plating are dissolved and removed with an acid or an oxidizing agent to form an electroless plating adhesive. The surface of the adhesive layer 2 is roughened to provide an octopus-shaped anchor.

Here, as the acid, for example, a strong acid such as phosphoric acid, hydrochloric acid or sulfuric acid, or an organic acid such as formic acid or acetic acid can be used. In particular, it is desirable to use an organic acid. This is because the metal conductor layer 4 exposed from the via hole opening 6 is hardly corroded when the roughening treatment is performed. On the other hand, as the oxidizing agent, it is desirable to use an aqueous solution of chromic acid or permanganate (such as potassium permanganate).

The above-mentioned roughening is performed by using a maximum surface roughness Rmax0.
1-20 μm is preferred. If the thickness is too large, the roughened surface itself is easily damaged and peeled off, and if the thickness is too small, the adhesion decreases.

(5) Next, a catalyst nucleus is applied to the wiring substrate having the surface of the interlayer resin insulating layer 2 roughened. It is desirable to use a noble metal ion or a noble metal colloid for providing the catalyst nucleus. Generally, palladium chloride or a palladium colloid is used. In order to fix the catalyst core, it is desirable to perform a heat treatment. Palladium is suitable for such a catalyst core.

(6) Subsequently, electroless plating is applied to the entire surface of the interlayer resin insulating layer 2 to which the roughened catalyst nuclei have been applied to form an electroless plated film 12 (see FIG. 3A). The thickness of the electroless plating film 12 is preferably 0.1 to 5 μm.

Next, a plating resist 3 is formed on the surface of the electroless plating film 12 (see FIG. 3B). A photosensitive resin film (dry film) is laminated on the formed electroless plating film 12, and on this photosensitive resin film,
The plating resist 3 can be formed by placing a photomask (preferably a glass substrate) on which the plating resist pattern is drawn in close contact, exposing and developing.

(7) Next, electroplating is performed, an electroplating film is formed on the portion of the electroless plating film 12 where the plating resist is not formed, and the conductor layer 5 and the via hole 7 are formed. Its thickness is preferably 5 to 20 μm. Copper plating is preferred for this electroplating. After the electroplating, the nickel film 14 is formed by at least one method selected from electrolytic nickel plating, electroless nickel plating, and sputtering (see FIG. 3C). This is because an alloy plating made of Cu-Ni-P is easily deposited on the nickel film 14. In addition, since the nickel film functions as a metal resist, there is an effect that excessive etching is prevented even in a subsequent process.

(8) Subsequently, after the plating resist 3 is removed, the electroless plating film 12 existing under the plating resist is replaced with a mixed solution of sulfuric acid and hydrogen peroxide, sodium persulfate, ammonium persulfate, or the like. Removal is performed with an etching solution composed of an aqueous solution to obtain an independent conductor layer 5 composed of three layers of an electroless plating film 12, an electrolytic plating film 13, and a nickel film 14 and via holes 7 (see FIG. 3D). The palladium catalyst nuclei on the roughened surface exposed to the non-conductive portion are dissolved and removed with chromic acid, sulfuric acid-hydrogen peroxide aqueous solution or the like.

(9) Next, the conductor layer 5 and the via hole 7
A roughening layer 11 is provided on the surface of the substrate, and a layer of the above-described adhesive for electroless plating is formed as the interlayer resin insulating layer 2 (see FIG. 4A).

(10) A via hole opening 6 is provided in the interlayer resin insulation layer 2 and the interlayer resin insulation layer 2
The surface of is roughened. (See FIG. 4B).

(11) Subsequently, after a catalyst nucleus is provided on the surface of the roughened interlayer resin insulating layer 2, an electroless plating film 12 is formed (see FIG. 4C).

(12) The plating resist 3 is formed on the surface of the electroless plating film 12, and the electroplating film 13 and the nickel plating film 14 are formed on the portion where the plating resist 3 is not formed as described above (FIG. 4 (d)).

(13) The plating resist 3 is removed, the electroless plating film 12 under the plating resist is removed, and the conductor layer 5, the via hole 7 and the plane layer 21 are provided.
A six-layer build-up substrate is obtained (see FIG. 5).

(14) The conductor layer 5, the via hole 7, and the plane layer 2 of the build-up substrate thus obtained.
1, a roughened layer 11 is formed, and a pad 16 and a plane layer 2 are formed.
1 is covered with an organic resin insulating layer 15 having an opening 18 for partially exposing it (see FIG. 6). The thickness of the organic resin insulating layer is preferably 5 to 40 μm. If the thickness is too small, the insulation performance is reduced, and if the thickness is too large, the opening becomes difficult, and it comes into contact with the solder, causing cracks and the like.

Various resins can be used as the resin constituting the organic resin insulating layer. For example, bisphenol A
A type epoxy resin, a bisphenol A type epoxy resin acrylate, a novolak type epoxy resin, and a resin obtained by curing a novolak type epoxy resin acrylate with an amine-based curing agent or an imidazole curing agent can be used.

The organic resin insulating layer having such a configuration has an advantage that migration of lead (a phenomenon in which lead ions diffuse in the organic resin insulating layer) is small. Moreover,
This organic resin insulation layer has excellent heat resistance and alkali resistance,
It does not deteriorate even at the temperature at which the conductive adhesive such as solder melts (around 200 ° C.), and does not decompose with a strongly basic plating solution such as nickel plating or gold plating.

Here, as the acrylate of the novolak type epoxy resin, an epoxy resin obtained by reacting glycidyl ether of phenol novolak or cresol novolak with acrylic acid, methacrylic acid or the like can be used. The imidazole curing agent is desirably liquid at 25 ° C. This is because a liquid can be uniformly mixed.

As such a liquid imidazole curing agent, 1-benzyl-2-methylimidazole (product name: 1)
B2MZ), 1-cyanoethyl-2-ethyl-4-methylimidazole (product name: 2E4MZ-CN), and 4-methyl-2-ethylimidazole (product name: 2E4MZ) can be used.

The amount of the imidazole curing agent is desirably 1 to 10% by weight based on the total solid content of the organic resin insulating layer. The reason for this is that if the added amount is within this range, uniform mixing is easy. In the composition before curing of the organic resin insulating layer, it is desirable to use a glycol ether-based solvent as a solvent. This is because an organic resin insulating layer using such a composition does not generate free oxygen, does not oxidize the pad surface, and has little harm to the human body.

Examples of the glycol ether solvents include:
Desirably, diethylene glycol dimethyl ether (D
At least one selected from MDG) and triethylene glycol dimethyl ether (DMTG) is used. This is because these solvents can completely dissolve benzophenone and Michler's ketone as reaction initiators by heating at about 30 to 50 ° C. The amount of the glycol ether solvent is preferably 10 to 40% by weight based on the total weight of the composition of the organic resin insulating layer.

The composition of the organic resin insulating layer as described above includes, in addition to the above, various antifoaming agents and leveling agents, thermosetting resins for improving heat resistance and base resistance and imparting flexibility.
A photosensitive monomer or the like can be added to improve the resolution. For example, as the leveling agent, one made of a polymer of an acrylate ester is preferable. Further, Irgacure I907 manufactured by Ciba-Geigy is preferably used as an initiator, and DETX-S manufactured by Nippon Kayaku is preferable as a photosensitizer. Further, a dye or a pigment may be added to the composition of the organic resin insulating layer. This is because the wiring pattern can be hidden. It is desirable to use phthalocyanine green as this dye.

As the thermosetting resin as an additional component, a bisphenol type epoxy resin can be used. This bisphenol type epoxy resin includes a bisphenol A type epoxy resin and a bisphenol F type epoxy resin, and when importance is attached to base resistance, the former is required to reduce viscosity (when importance is attached to coating properties). The latter is better.

Further, these organic resin insulating layer compositions include:
0.5 to 10 Pa · s at 25 ° C., more preferably 1 to 10 Pa · s
10 Pa · s is preferable. This is because the viscosity is easy to apply with a roll coater.

(15) After forming a metal film 19, which is a corrosion-resistant metal such as a gold plating film, a nickel plating film and a gold plating film, in the opening 18, the lower surface side of the package substrate (daughter board, motherboard). A solder paste is printed as the conductive adhesive 17 in the opening 18 to be the connection surface. The solder paste has a viscosity of 50 to 400
It is preferable to carry out in the range of PaS. Further, the conductive connection pin 100 is attached to and supported by an appropriate pin holding device, and the fixing portion 101 of the conductive connection pin 100 is brought into contact with the conductive adhesive 17 in the opening 16, and at 240 to 270 ° C. Reflow is performed to fix the conductive connection pins 100 to the conductive adhesive 17 (see FIG. 7). Or, put the conductive adhesive in the form of a ball or the like in the opening, or
After attaching the conductive connection pin to the conductive connection pin and attaching the conductive connection pin to the plate-shaped fixed portion side, reflow may be performed. In addition,
In the opening 18 on the upper surface side of the package substrate 311, a solder bump 2 connectable to a component such as an IC chip is provided.
30 were provided.

The conductive connection pin 100 used in the present invention
A so-called T-shaped pin composed of a plate-shaped fixing portion 101 and a columnar connecting portion 102 protruding substantially at the center of the plate-shaped fixing portion 101 is preferably used. Plate-shaped fixing part 101
Is a portion fixed to the outermost conductor layer 5 of the package substrate to be the pad 16 via the conductive adhesive 17 and is appropriately formed in a circular shape or a polygonal shape according to the size of the pad. . The shape of the connection portion 102 is not limited as long as it can be inserted into the connection portion such as a terminal of another substrate, and may be any shape such as a cylinder, a prism, a cone, or a pyramid.

The material of the conductive connection pin 100 is not limited as long as it is a metal, and it is preferable that the conductive connection pin 100 be formed of at least one kind of metal among gold, silver, copper, iron, nickel, cobalt, tin, lead and the like. Good. In particular, iron alloys such as "Kovar" (Ni-Co-Fe), stainless steel, and phosphor bronze which is a copper alloy are exemplified. This is because they have excellent electrical characteristics and workability as a conductive connection pin. Also,
The conductive connection pin may be formed of one kind of metal or alloy, or may be coated with another metal layer for preventing corrosion or improving strength. Further, it may be formed of an insulating material such as ceramic, and its surface may be covered with a metal layer.

In the conductive connecting pin 100, the columnar connecting portion 102 has a diameter of 0.1 to 0.8 mm and a length of 1.0 to 1.0.
10 to 10 mm, and the diameter of the plate-shaped fixing portion 101 is 0.5 to 2.
It is desirable to set the range to 0 mm, and it is appropriately selected according to the size of the pad, the type of the socket of the motherboard to be mounted, and the like.

As the conductive adhesive 17 used for the package substrate of the present invention, solder (tin-lead, tin-antimony, silver-tin-copper, etc.), conductive resin, conductive paste and the like can be used. it can. It is preferable to use a conductive adhesive having a melting point in the range of 180 to 280 ° C.
Thereby, the adhesive strength of the conductive connection pin is 2.0 kg / pin.
The above is ensured, and the conductive connection pins do not fall off or tilt due to heat applied under heat cycle conditions or during mounting,
The electrical connection is also ensured. Most preferably, it is formed of solder. This is because it has excellent connection strength with the conductive connection pin, is resistant to heat, and is easily bonded.

When the conductive adhesive 17 is formed by solder, it is preferable to use solder having a composition such as Sn / Pb = 95/5, 60/40. The melting point of the solder used is preferably in the range of 180 to 280 ° C. Particularly preferred is a temperature in the range of 200 to 260 ° C. Thereby, the variation in the adhesive strength of the conductive connection pins is reduced, and the heat applied during mounting does not damage the resin layer constituting the package substrate.

FIG. 12 is a plan view showing the plane layer 21. FIG. The plane layer 21 has a circular conductor non-forming portion 21.
It is formed in a mesh shape by disposing a.
The connection portion 21b to which the conductive connection pin is connected is provided so as to avoid the conductor non-formed portion 21a. It should be noted that the mesh may be rectangular instead of circular, and it is also possible that no mesh is provided on the plane layer.

As shown in FIG. 7, in the package substrate 311 according to the first embodiment of the present invention, a plane layer 21 for forming a power supply layer is disposed on the surface of the substrate.
The electrical resistance from the external substrate (for example, a daughter board) to the plane layer 21 is reduced by directly connecting the conductive connection pins 100 to the conductive layers. This facilitates power supply from the daughter board side, enables a large current to be supplied to the IC chip, and allows the plane layer 21 constituting the power supply layer to perform a sufficient function.

[Second Embodiment] FIG. 8 shows a cross section of a package substrate 312 according to a second embodiment of the present invention, and FIG. 9 shows a configuration in which conductive connection pins 400 surrounded by a circle in FIG. 8 are provided. The pad portion is shown in an enlarged manner. As shown in FIG. 9, the pads 16 of the package substrate 312 of the second embodiment are covered with an organic resin insulating layer (through-hole layer) 15 in which an opening 18 for partially exposing the pad 16 is formed. The fixing portion 101 of the conductive connection pin 400 is fixed to the pad 16 exposed from the opening 18 via a conductive adhesive (Sn / Sb = 95: 5) 17. As can be understood from the figure, the organic resin insulating layer 15 covers the periphery of the pad 16 so as to be pressed down, so that the conductive connection pin 15 can be used during a heat cycle or when mounting the package substrate on a motherboard. Even if a stress is applied to 400, destruction of pad 16 and separation from interlayer resin insulating layer 15 can be prevented. Also, it is difficult to peel off even when bonding different materials such as metal and resin.

As shown in FIG. 8, in the package substrate according to the second embodiment of the present invention, a plane layer 21 forming an earth layer is disposed on the surface of the substrate, and conductive connection pins 400 are formed on the plane layer 21. The direct connection reduces the electrical resistance from the external substrate (eg, daughter board) to the plane layer 21. Thus, even in the plane layer constituting the ground layer, the ground layer is connected to the ground line on the daughter board via the low-resistance conductive connection pin, thereby sufficiently fulfilling the role of preventing noise.

In the package substrate 312 of the second embodiment, the material of the conductive connection pin 400 has at least one kind of high flexibility selected from copper or copper alloy, tin, zinc, aluminum, and noble metal. Made of metal. In particular, phosphor bronze, which is a copper alloy, may be mentioned. This is because they have excellent electrical characteristics and workability as a conductive connection pin. The surface of the conductive connection pin may be covered with another metal layer to prevent corrosion or improve strength.

As can be understood from FIG. 9, since the conductive connection pins 400 are made of a material having excellent flexibility, they are added to the conductive connection pins 400 when the package substrate is mounted on another substrate. The stress can be absorbed by the connection portion 102 flexing as shown by a dotted line in the drawing.

[Third Embodiment] FIG. 10 shows a cross section of a package substrate 313 according to a third embodiment of the present invention.
Is a conductive connection pin 500 encircled in FIG.
The pad portion provided with is shown in an enlarged manner. As can be understood from FIG. 11, the conductive connecting pins 500 of the package substrate 313 of the third embodiment are connected to
3 is provided, the connector is flexible and easy to bend. When the package substrate is attached to a motherboard or the like, the stress applied to the conductive connection pins 500 is reduced by the connection portion 102 through the narrow portion 103. It can be absorbed by bending.

[Fourth Embodiment] Basically the same as the second embodiment, except that a ball-shaped solder is attached to the conductive connection pins, and then the conductive connection pins are provided.

[0068]

As described above, according to the present invention,
An electric resistance from the external substrate to the plane layer is reduced by disposing a plane layer on the surface of the substrate and directly connecting conductive connection pins to the plane layer. Thereby, the function of the plane layer can be sufficiently performed.

FIG. 13 shows the results of evaluating the package substrates of the respective embodiments. Evaluation items include the minimum bonding strength of the conductive connection pins after bonding, a heating test (reproduction of a virtual IC actual measurement state, evaluation by passing a substrate on which the pins are disposed through a nitrogen reflow furnace at 250 ° C.), and After heat cycle conditions (10000 cycles at 130 ° C./3 minutes + −65 ° C./3 minutes as one cycle), the state of each pin, minimum adhesive strength, and conduction test were performed.

[Brief description of the drawings]

1 (a), 1 (b), 1 (c), 1
(D) is a manufacturing process diagram of the package substrate according to the first example of the present invention.

2 (a), 2 (b), 2 (c), 2
(D) is a manufacturing process diagram of the package substrate according to the first example of the present invention.

3 (a), 3 (b), 3 (c), 3
(D) is a manufacturing process diagram of the package substrate according to the first example of the present invention.

4 (a), 4 (b), 4 (c), 4
(D) is a manufacturing process diagram of the package substrate according to the first example of the present invention.

FIG. 5 is a sectional view of a package substrate according to the first embodiment of the present invention.

FIG. 6 is a sectional view of the package substrate according to the first embodiment of the present invention.

FIG. 7 is a sectional view of the package substrate according to the first embodiment of the present invention.

FIG. 8 is a sectional view of a package substrate according to a second embodiment of the present invention.

FIG. 9 is an enlarged sectional view of a portion where a conductive connection pin is connected to a pad in FIG. 8;

FIG. 10 is a sectional view of a package substrate according to a third embodiment of the present invention.

FIG. 11 is an enlarged sectional view of a portion where a conductive connection pin is connected to a pad in FIG. 10;

FIG. 12 is a plan view showing a plane layer.

FIG. 13 is a table showing evaluation results of the package substrates of the respective examples.

[Explanation of symbols]

 Reference Signs List 1 core substrate 2,200 interlayer resin insulating layer 3 plating resist 4 conductive layer 4a roughened surface 5 conductive layer 6 via hole opening 7 via hole 8 copper foil 9 through hole 9a roughened surface 91 land of through hole 10 resin filler DESCRIPTION OF SYMBOLS 11 Roughening layer 12 Electroless plating film 13 Electroplating film 14 Nickel plating layer 15 Organic resin insulating layer 16 Pad 16a Extension part 16b Body part 17 Conductive adhesive 18 Opening 21 Plain layer 100 Conductive connection pin 101 Fixed part 102 connecting part 103 constricted part 311, 312, 313 package substrate 400, 500 conductive connecting pin

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/46 H05K 3/46 Z Q H01L 23/12 K (72) Inventor Naohiro Hirose Ibikawa, Ibi-gun, Gifu Prefecture 1-1, Ikiden, Ogaki-Kita Plant (72) Inventor, Masanori Kawade 1-1, Ibigawa-cho, Ibi-gun, Ibi-gun, Gifu Pref., Ogaki-Kita Plant F-term (reference) EE15 EE34 GG26 HH40 JJ06 JJ35 5E344 BB10 CC23 CD14 DD02 EE16 EE21 5E346 AA02 AA43 CC08 CC09 CC32 EE31 FF07 FF10 FF13 FF14 FF18 GG15 GG17 GG27 HH31

Claims (9)

[Claims] 1. A plane layer which is a conductor layer provided on a surface of a substrate, an organic resin insulating layer provided by forming an opening on a surface of the plane layer, and exposed from an opening of the organic resin insulating layer. A conductive connection pin fixed to the plane layer via a conductive adhesive. 2. A plane layer provided on the surface of the substrate, a pad provided on the surface of the substrate, an organic resin insulating layer provided with an opening formed on the surface of the plane layer and the pad, A package substrate, comprising: a conductive connection pin fixed to the plane layer and the pad exposed through an opening of an organic resin insulating layer via a conductive adhesive. 3. The substrate according to claim 1, wherein the substrate is a built-up substrate having at least one structure in which conductor layers and interlayer resin insulation layers are alternately laminated.
A package substrate according to claim 1. 4. The package substrate according to claim 2, wherein a peripheral portion of said pad is covered with an organic resin insulating layer. 5. The conductive connecting pin comprises a columnar connecting portion and a plate-like fixing portion, and is made of at least one metal selected from copper or copper alloy, tin, zinc, aluminum, and a noble metal. The package substrate according to claim 1, wherein: 6. A method according to claim 1, wherein said conductive connecting pin comprises a columnar connecting portion and a plate-like fixing portion, and said columnar connecting portion is formed with a constricted portion having a diameter smaller than that of another portion. The package substrate according to claim 1. 7. The conductive adhesive has a melting point of 180-2.
The package substrate according to any one of claims 1 to 6, wherein the temperature is 80 ° C. 8. The method according to claim 1, wherein the conductive adhesive is made of at least one of tin, lead, antimony, silver, gold, and copper. Package substrate. 9. The conductive adhesive is Sn / Pb, Sn
9. The package substrate according to claim 1, wherein the package substrate is an alloy of / Sb, Sn / Ag, and Sn / Sb / Pb.