JP5998644B2 - Multilayer substrate and method for manufacturing multilayer wiring board - Google Patents

Description

  The present invention relates to a multilayer wiring board having a very thin plate thickness used for a semiconductor element mounting package and a method for manufacturing the same.

  In recent years, electronic devices have been further reduced in size, weight, and functionality, and along with this, higher integration and miniaturization of wiring are rapidly progressing, and miniaturization of wiring is progressing. In addition, there is an increasing demand for a downsized package such as a so-called chip size package (CSP; Chip Size / Scale Package) that is almost the same size as a semiconductor chip. On the other hand, the wiring that can be formed with good yield by the subtractive method of forming the wiring by etching is about conductor width (L) / conductor gap (S) = 50 μm / 50 μm.

  In order to realize a finer conductor width / conductor gap = about 35 μm / 35 μm, in Patent Document 1, two peelable peelable copper foils are stacked and cured with a prepreg sandwiched between them. A support substrate is produced. Then, a plating resist is formed on the peelable copper foil, a wiring layer in which a conductor is formed to a necessary thickness by electrolytic metal plating is formed, and after removing the resist, an interlayer insulating resin layer is formed on the wiring layer. The wiring pattern is sequentially built up to form a multilayer structure.

  Then, the multilayer structure formed on both sides of the support substrate is separated by peeling the peelable copper foil, and the thin metal layer of the peelable copper foil remaining on the surface of the multilayer structure is removed by soft etching. A technique for manufacturing a multilayer wiring board having a very thin board thickness is disclosed.

JP 2005-101137 A

  In the technique of Patent Document 1, the peelable copper foil is bonded to the outside of the insulating resin material of the prepreg cured by laminating the peelable copper foil via the prepreg on the outside of the support substrate, and copper plating is performed on the peelable copper foil. Thus, a wiring pattern was formed, a plurality of interlayer insulating resin layers and wiring patterns were laminated thereon, and then the peelable copper foil was peeled off. Then, the peelable copper foil layer is removed by etching to expose the wiring pattern formed thereon and the surface of the interlayer insulating resin layer.

  In the technique of Patent Document 1, since the multilayer wiring board was manufactured in this way, the wiring pattern of the connection terminal was embedded in the surface of the insulating resin layer facing the peelable copper foil side, and the wiring pattern of the connection terminal was Via holes aligned with each other were formed in the insulating resin layer.

  In this conventional technique, the connection terminals and the via holes cannot be stably manufactured at a pitch of 130 μm or less because of the positional alignment accuracy of the connection terminals and the via holes. That is, when the connection terminal is formed as small as the diameter of the via hole, the shape of the connection terminal that is finally exposed on the surface of the insulating resin layer of the multilayer wiring board when the position of the via hole is shifted from the connection terminal is processed. Jumped out to one side, and the shape in which the connecting terminal part was exposed from the insulating resin layer became abnormal. The abnormal connection terminal portion has a problem that the reliability of connection with the bump (connection terminal) of the semiconductor chip is low. In addition, the distance between the connection terminal portion and the adjacent bump becomes short, and when soldering the bump of the semiconductor chip, a short circuit occurs between the adjacent bump and the solder, or the insulation reliability deteriorates. there were.

  An object of the present invention is to solve the above-described problem and obtain a multilayer wiring board that can be electrically connected to a high-density bump having an IC chip pitch of about 130 μm with high reliability and has a very thin plate thickness. .

The present invention, in order to solve the above problems, a laminated substrate used in the production method of the multi-layer wiring board, a metal multilayer structure comprising a semi-cured insulating resin sheet on the outside of the supporting substrate, a plurality of metal layers that can be peeled off has a foil, the said an insulating resin material in a semi-cured insulating resin, the outer peripheral portion of the metal foil of the multilayer structure is a laminated board, wherein Rukoto having a structure that covers together.

The present invention also provides a semi-cured insulating resin sheet stacked on the outer side of a support substrate, the outer surface of the semi-cured insulating resin sheet is smaller in size than the semi-cured insulating resin sheet, and has a plurality of metal layers on both sides. sometimes the interlayer but laminating a laminated metal sheet formed by releasably laminated, laminating overlapping with the ultrathin copper foil layer on the outside, a first interlayer insulating resin layer on the outer side of the laminated metal sheet Forming a laminated substrate that covers the outer peripheral portion of the metal foil of the multilayer structure with the insulating resin by allowing the insulating resin of the insulating resin layer to flow on the surface of the outer edge of the metal foil of the multilayer structure ;
Forming a via hole pilot hole reaching the laminated metal sheet of the laminated metal sheet by a drilling laser beam from outside the interlayer insulating resin layer, a first via hole filling the via hole pilot hole by copper plating, and the first Forming a land of the first via hole and a first wiring pattern outside the first interlayer insulating resin layer; and a next interlayer insulating resin outside the first interlayer insulating resin layer and the first wiring pattern. Forming a multilayer wiring structure by alternately laminating layers and wiring pattern layers, separating the multilayer wiring structure from the support substrate by peeling the laminated metal sheet, and The top bottom of the frustoconical via hole embedded in the interlayer insulating resin layer by the quick etching of the ultrathin copper foil layer is smaller in diameter than the bottom bottom A method for manufacturing a multilayer wiring board, characterized in that a step of forming a multilayer wiring board was exposed outside.

  According to the present invention, the multilayer wiring structure 30 in which the upper base of a truncated cone-shaped via hole 32 embedded in the interlayer insulating resin layer 31 is smaller than the diameter of the lower base is exposed to the outside. A multilayer wiring board made of can be obtained.

  Since the diameter of the upper base of the exposed via hole 32 is about 50 μm and small, by connecting bumps (connection terminals) of the IC chip to the upper base, high-density component terminals with an IC chip pitch of about 130 μm and There is an effect that electrical connection can be made with high reliability.

It is a fragmentary sectional view which shows embodiment of the manufacturing method of this invention (the 1). It is a fragmentary sectional view which shows embodiment of the manufacturing method of this invention (the 2). It is a fragmentary sectional view which shows embodiment of the manufacturing method of this invention (the 3). It is a fragmentary sectional view which shows embodiment of the manufacturing method of this invention (the 4). It is a fragmentary sectional view which shows embodiment of the manufacturing method of this invention (the 5). It is a fragmentary sectional view of the multilayer wiring board of modification 2 of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 6 show an embodiment of a method for producing a multilayer wiring board according to the present invention in the order of steps.

Materials and structures used for the structure will be described below by taking an embodiment of the manufacturing method as an example.
(Support substrate)
First, as shown in FIG. 1A, the supporting substrate 10 is a substrate having a thickness of 0.04 mm to 0.4 mm, and has a copper foil 11 having a thickness of 18 μm on both sides, and an organic resin is made of glass, polyimide, liquid crystal, or the like. A copper clad laminate (for example, a size of 610 × 510 mm) made of a material impregnated in a reinforcing fiber is used.

  As the organic resin material constituting the support substrate 10, an organic resin mainly composed of epoxy, acrylic, urethane, epoxy acrylate, phenol epoxy, polyimide, polyamide, cyanate, and liquid crystal is used. it can. Alternatively, a substrate in which a filler made of silica, butyl organic material, calcium carbonate, or the like is included in the organic resin can be used.

(Copper foil roughening process for support substrate)
First, the surface of the copper foil 11 of the support substrate 10 is roughened by a soft etching process using an etchant such as perhydrosulfuric acid. Next, an alignment mark is formed in a pattern obtained by etching the copper foil 11 as an alignment mark on which the multilayer metal sheet 13 having a multilayer structure such as peelable copper foil is superimposed on the surface of the support substrate 10.

(Modification 1)
As a first modification, the support substrate 10 is made of glass (blue plate, non-alkali glass, quartz) or metal (mainly stainless steel, iron, copper, titanium, tungsten, magnesium, aluminum, chromium, molybdenum, etc.). Can also be used.

(Process of laminating a laminated metal sheet on a support substrate)
Next, as shown in FIG. 1B, the support substrate 10 having a size of, for example, 610 × 510 mm is centered, and outside the support substrate 10, the size of the same size as the support substrate 10 in plan view is 610 × 510 mm. A semi-cured insulating resin sheet 12a made of a prepreg or a resin film is overlaid, and a multilayered laminated metal sheet 13 having a size smaller than the semi-cured insulating resin sheet 12a and having a size smaller than 600 × 500 mm is overlaid on the outside. And the release film 20 is piled up on the outer side of the laminated metal sheet 13, and the laminated metal sheet 13 is laminated | stacked on the outer side of the support substrate 10 via the semi-hardened insulating resin sheet 12a with a vacuum lamination press.

  The semi-cured insulating resin sheet 12a outside the support substrate 10 is cured into an insulating resin material 12 by a laminating process that is heated and pressurized by a vacuum laminating press apparatus, and the support substrate made of the support substrate 10 and the insulating resin material 12 is used. The laminated substrate 100 in which the laminated metal sheet 13 is integrated on the outer surface is manufactured.

(Semi-cured insulating resin sheet)
The semi-cured insulating resin sheet 12a used here has a thickness of 0.04 mm to 0.4 m.
m (for example, 0.07 mm thickness) prepreg formed by impregnating a reinforcing fiber with an organic resin is used as the semi-cured insulating resin sheet 12a. The prepreg is preferably adjusted to be resin-rich. If necessary handling properties can be ensured, a semi-cured insulating resin sheet 12a made of a resin film not containing reinforcing fibers may be used.

  As the organic resin material of the semi-cured insulating resin sheet 12a, epoxy resin, bismaleimide-triazine resin (hereinafter referred to as BT resin), polyimide resin, PPE resin, phenol resin, PTFE resin, silicon resin, polybutadiene resin, polyester Organic resins such as resins, melamine resins, urea resins, PPS resins, PPO resins, cyanate resins, and cyanate ester resins can be used.

  As the reinforcing fiber, glass fiber, aramid nonwoven fabric, aramid fiber, polyester fiber, polyamide fiber, liquid crystal fiber, or the like can be used. In addition, the organic resin of the semi-cured insulating resin sheet 12a can include a filler made of silica, butyl organic material, calcium carbonate, or the like.

(Laminated metal sheet)
As the laminated metal sheet 13 having a multilayer structure in which a plurality of metal layers are detachably laminated, for example, a metal layer of a carrier copper foil layer 13a having a thickness of 10 μm to 35 μm (for example, 18 μm), and a thickness of 1 μm to 8 μm (for example, A peelable metal foil in which a metal layer of an ultrathin copper foil layer 13b having a thickness of 5 μm is peelably laminated is used. As a means for releasably laminating the metal layers of the carrier copper foil layer 13a and the ultrathin copper foil layer 13b, a method of releasably bonding with an adhesive or other releasable laminating methods is used.

  The laminated metal sheet 13 is stacked on the outside of the semi-cured insulating resin sheet 12a with the ultrathin copper foil layer 13b on the outside and the carrier copper foil layer 13a on the inside.

  As shown in FIG. 1B, the release metal film 20 is stacked on the outside of the laminated metal sheet 13, and the laminated metal sheet 13 is laminated on the outside of the support substrate 10 via the semi-cured insulating resin sheet 12a by a vacuum lamination press. To do. The conditions of the vacuum lamination press are carried out by adjusting the heating rate, pressure, and pressurization timing according to the material of the semi-cured insulating resin sheet 12a to be applied. In the case of using a material having high fluidity, adjustment may be made to slow the temperature increase rate or pressurization timing.

  Then, after the semi-cured insulating resin sheet 12a is solidified to form the insulating resin material 12, the release film 20 is peeled off, and the outer peripheral portion of the laminated metal sheet 13 having a size of 600 × 500 mm is formed as shown in FIG. A support substrate in which a frame portion 14 having a width of 5 mm is surrounded by the insulating resin material 12 and a thin resin thin film 15 connected to the insulating resin material 12 of the frame portion 14 is formed on the surface of the outer edge portion of the laminated metal sheet 13. The laminated substrate 100 is manufactured. In this state, the inner surface, side wall, and outer end of the laminated metal sheet 13 are covered with an integral insulating resin material.

(Modification 2)
As a second modified example, a thickness and rigidity that can sufficiently ensure rigidity after curing by lamination between the two laminated metal sheets 13 and having a size larger than that of the laminated metal sheet 13 without using the support substrate 10 are provided. The laminated substrate 100 can also be manufactured by sandwiching the semi-cured insulating resin sheet 12a to be the insulating resin material 12 with a vacuum lamination press. As shown in FIG. 6, the multilayer substrate 100 has a structure in which an insulating resin material 12 is formed between two multilayer metal sheets 13, and the size of the two multilayer metal sheets 13 is the size of the multilayer substrate 100. Smaller than. And the structure which the resin thin film 15 which is a part of the insulating resin material 12 covers the edge part of the outer surface of the laminated metal sheet 13 is formed. Eventually, also according to the modified example 2, the insulating resin material 12 in which the inner surface of the laminated metal sheet 13 and the end of the outer surface of the laminated metal sheet 13 are formed in an integral structure.
The laminated substrate 100 covered with can be manufactured.

(Release film)
In the step of FIG. 1 (b), the release film 20 sandwiched between the stainless steel press plate of the vacuum lamination press apparatus in the vacuum lamination press is a resin material such as polyphenylene sulfide or polyimide, stainless steel, brass or the like. A film made of a composite material combined with a metal material is used.

  As the heat shrinkage rate of the release film 20, the release film 20 having a heat shrinkage rate of 0.01 to 0.9% is used at the temperature at which the heat and pressure treatment is performed. Moreover, the release film 20 whose elongation reduction rate after the heat-pressing process of the release film 20 is 30% or less before the heat-pressing process is used.

  The form of the release film 20 is made of a resin material having a thickness of 10 to 200 μm. In particular, the surface of the release film 20 has an average roughness Ra specified in JIS B0601 of 300 nm to 1500 nm. A release film 20 subjected to (mat treatment) is used.

  In the process of FIG. 1B, the resin-rich semi-cured insulating resin sheet 12a is overlaid on the outside of the support substrate 10, the laminated metal sheet 13 is overlaid on the outside, and the average roughness Ra is 300 nm on the outside. The laminated substrate 100 is manufactured by stacking the release films 20 having been roughened (matte treatment) to 1500 nm or less, sandwiching them between press plates, and laminating them using a vacuum laminating press that heats and presses the press plates. To do.

  At that time, due to the effect of the mat treatment on the surface of the release film 20, the insulating resin material 12 of the frame portion 14 is connected to the surface of the outer edge portion of the laminated metal sheet 13 as shown in FIG. A thin resin thin film 15 is formed.

  The matting treatment of the surface of the release film 20, the resin rich degree of the semi-cured insulating resin sheet 12a, and the heating / pressurizing conditions of the vacuum lamination press are adjusted so that the resin thin film 15 is appropriately formed. As a result, the resin material of the semi-cured insulating resin sheet 12 a that has been heated and pressurized appropriately flows out onto the surface of the outer edge portion of the laminated metal sheet 13, and the insulating resin material 12 is formed on the outer edge portion of the laminated metal sheet 13. The resin thin film 15 has a thickness of 3 μm or less and a width in the range of 0.1 mm to 10 mm.

  As a result, the multilayer substrate 100 is formed such that the size of the multilayer metal sheet 13 is smaller than the overall size of the multilayer substrate 100. Then, as shown in the partial cross-sectional view of FIG. 2C, the insulating resin material 12 of the frame portion 14 that is the outside of the laminated metal sheet 13 includes the inner surface and the outer end of the laminated metal sheet 13, and the laminated metal. The outer peripheral portion of the exposed surface of the sheet 13 is integrally covered. Thereby, peeling of the layer of the laminated metal sheet 13 in the substrate manufacturing process using the laminated substrate can be effectively prevented.

  The resin thin film 15 of the laminated substrate 100 is connected to the insulating resin material 12 of the frame portion 14 to insulate the boundary line of the peeling interface between the carrier copper foil layer 13a and the ultrathin copper foil layer 13b of the laminated metal sheet 13. It has the effect of being embedded in the material 12 for protection. Thereby, it is possible to prevent peeling of the boundary surface between the carrier copper foil layer 13a and the ultrathin copper foil layer 13b of the laminated metal sheet 13 due to stress in the subsequent manufacturing process, and manufacturing failure due to peeling of the interface. There is an effect that can be prevented.

In particular, by setting the width of the resin thin film 15 to be 0.1 mm or more, there is an effect that the boundary line of the peeling interface of the laminated metal sheet 13 is sufficiently protected. There is an effect of preventing a problem that the sheet 13 is unexpectedly peeled off. On the other hand, if the width of the resin thin film 15 is larger than 10 mm, the area of the effective region in which the laminated metal sheet 13 is not covered with the resin thin film 15 becomes narrow and the product cost increases. Preferably, the manufacturing conditions are adjusted so that the resin thin film 15 covers the laminated metal sheet 13 with a width of 0.5 μm or more and 5 mm or less.

  On the surfaces of the resin thin film 15 and the insulating resin material 12 of the frame portion 14, the roughness of the matte release film 20 having an average roughness Ra of 300 nm to 1500 nm is transferred. Thereby, there is an effect that the adhesion force between the metal plating layer to be formed later and the surface of the resin thin film 15 and the surface of the insulating resin material 12 of the frame portion 14 can be increased. When Ra is smaller than 300 nm, the adhesive force expressed is weak, and the metal plating layer provided on the surface of the insulating resin material 12 peels during the process. Moreover, when Ra becomes larger than 1500 nm, the insulating resin material 12 which becomes a convex portion is easily detached, and this detached substance causes a decrease in yield during the process.

  Here, in the case where the support substrate 10 having the copper foil 11 on both sides and the semi-cured insulating resin sheet 12a are laminated on both sides of the laminate, the laminate substrate 100 is laminated by sandwiching them between the laminated metal sheets 13. Is produced, the laminated substrate 100 is reinforced with the copper foil 11. Also, the copper foil 11 matches the thermal expansion coefficient of the surface of the multilayer substrate 100 to the thermal expansion coefficient of copper, and later builds up the outer surface of the multilayer substrate 100 to form the copper wiring pattern 33 and the surface of the multilayer substrate 100. There is an effect that the difference in thermal expansion coefficient between the two can be reduced, and the thermal stress generated at the interface between the multilayer substrate 100 and the wiring pattern 33 due to the heat treatment in the manufacturing process can be reduced.

(Interlayer insulating resin layer formation process)
Next, as a pretreatment for forming the interlayer insulating resin layer 31, the surface of the laminated metal sheet 13 is roughened by an intergranular corrosion etching process, a blackening process by an oxidation-reduction process, or an overwater Roughening is performed by sulfuric acid-based soft etching.

  Next, as shown in FIG. 2D, the interlayer insulating resin layer 31 is thermocompression-bonded on the laminated metal sheet 13 by roll lamination or lamination press. For example, an epoxy resin having a thickness of 45 μm is roll laminated. When glass epoxy resin is used, copper foil of any thickness is stacked and thermocompression bonded with a lamination press.

  As a resin material of the interlayer insulating resin layer 31, epoxy resin, bismaleimide-triazine resin (hereinafter referred to as BT resin), polyimide resin, PPE resin, phenol resin, PTFE resin, silicon resin, polybutadiene resin, polyester resin, melamine resin Organic resins such as urea resin, PPS resin, PPO resin, cyanate resin, and cyanate ester resin can be used. In addition, these resins can be used alone, or a combination of resins such as mixing a plurality of resins or preparing a compound can be used. Furthermore, an interlayer insulating resin layer 31 in which a glass fiber reinforcing material is mixed into these materials can be used. As the reinforcing material, an aramid nonwoven fabric, an aramid fiber, or a polyester fiber can be used.

(Via hole and wiring pattern formation process)
Next, as shown in FIG. 3E, a via hole prepared hole 32a for interlayer connection is formed by a laser beam for drilling. When copper foil is used for thermocompression bonding of the interlayer insulating resin layer 31, as a pretreatment for forming the via hole prepared hole 32a, the entire copper foil is etched, or an opening for the via hole prepared hole 32a is formed in the copper foil. By performing the etching process to be formed or the surface treatment of the copper foil, the laser absorption of the copper foil in the via hole pilot hole 32a is improved, and the via hole pilot hole 32a is formed by a laser beam. The via hole prepared hole 32a is formed to have an outer hole diameter of about 80 μm and a hole bottom hole diameter of about 50 μm, and the outer hole diameter is larger than the hole bottom diameter and the truncated cone is inverted.

  Next, as shown in FIG. 3 (f), the wall surface of the via hole prepared hole 32a and the surface of the interlayer insulating resin layer 31 are subjected to electroless plating, and an electrolytic copper plating layer is formed on the outer side and filled with copper plating. A via hole 32 is formed. The via hole 32 is formed in a truncated cone shape when the support substrate side is on the upper side and the outer side of the substrate is on the lower side.

  Next, a photosensitive plating resist film is formed on the surface of the electrolytic copper plating layer, exposed and developed to form an etching resist pattern, and the electrolytic copper plating pattern is etched while protecting with the etching resist. Next, the pattern of the etching resist is peeled to form via hole lands 32 b and wiring patterns 33 on the interlayer insulating resin layer 31 as shown in FIG.

  Then, the formation process of the interlayer insulation resin layer 34 by the same build-up method and the formation process of the via hole 35 and the wiring pattern are repeated on the wiring pattern 33 and the interlayer insulation resin layer 31 as shown in FIG. Then, a multilayer wiring structure 30 is formed on the multilayer substrate 100 by building up a plurality of interlayer insulating resin layers 31 and 34, via holes 32 and 35, and wiring patterns.

  Next, the surface of the multilayer wiring structure 30 is roughened with a microetching agent, and then a thick coating of an azole compound is formed to improve the solder resist adhesion. When the adhesion between the multilayer wiring structure 30 and the solder resist 36 can be secured after the roughening treatment, the treatment with the azole compound may not be performed. Next, a photosensitive solder resist is applied to the outer surface of the multilayer wiring structure 30 by a roll coater or printing, and dried at 70 ° C. to form a solder resist 36 film.

Next, the film of the solder resist 36 is exposed and developed, the pad portion is opened, and heat-cured at 180 ° C., and then the solder resist 36 is insulated by ultraviolet irradiation at 100 mJ / cm ² .

  Next, an etching resist of a desired size is pasted on the surface of the multilayer wiring structure 30, and the frame portion 14 is cut off by cutting the multilayer wiring structure 30 and the laminated substrate 100 along the cutting line 16 in FIG. The boundary line of peeling of the laminated metal sheet 13 is exposed on the cut surface. Then, as shown in FIG. 5 (j), the ultrathin copper foil layer 13b is peeled from the carrier copper foil layer 13a of the laminated metal sheet 13 from the exposed peeling boundary line, so that the laminated substrate having a thickness of 0.4 mm is obtained. The multilayer wiring structure 30 is separated from 100.

  Next, the ultrathin copper foil layer 13b of the multilayer wiring structure 30 is removed by quick etching from the multilayer wiring structure 30 thus separated, and is embedded in the interlayer insulating resin layer 31 as shown in FIG. A multilayer wiring structure 30 is obtained in which the upper base of the inverted frustoconical via hole 32 having a diameter smaller than the diameter of 80 μm of the lower base is exposed to the outside.

  Since the diameter of the upper surface (upper bottom) of the exposed via hole 32 is as small as about 50 μm, an IC chip bump having a pitch of about 130 μm is connected to the upper bottom of the via hole 32 by connecting a bump (connection terminal) of the IC chip. There is an effect that electrical connection can be made with high density component terminals with high reliability.

(Land plating)
Next, at least 3 μm of electroless Ni plating is formed on the opening portion of the solder resist 36 and the upper bottom surface of the via hole 32, and 0.03 μm or more of electroless Au plating is formed thereon via electroless Pd plating. . The electroless Au plating may be formed with a thickness of 1 μm or more. Furthermore, it is also possible to pre-coat solder thereon. Alternatively, electrolytic Ni plating may be formed at 3 μm or more in the solder resist opening, and electrolytic Au plating may be formed thereon at 0.5 μm or more. Furthermore, an organic rust preventive film may be formed in the solder resist opening in addition to the metal plating.
(Outline processing)
Next, the outer shape of the multilayer wiring structure 30 is processed with a dicer or the like and separated into individual multilayer wiring boards.

DESCRIPTION OF SYMBOLS 10 ... Support substrate 11 ... Copper foil 12 ... Insulating resin material 12a ... Semi-hardened insulating resin sheet 13 ... Laminated metal sheet 13a ... Carrier copper foil layer 13b ... Ultra-thin copper Foil layer 14 ... Frame 15 ... Resin thin film 16 ... Cutting line 20 ... Release film 30 ... Multilayer wiring structure 31, 34 ... Interlayer insulating resin layers 32, 35 ... Via hole 32a ... via hole pilot hole 32b ... via hole land 33 ... wiring pattern 36 ... solder resist 100 ... multilayer substrate

Claims (2)

Laminated substrate used for manufacturing the multi-layer wiring board,
A semi-cured insulating resin sheet on the outside of the support substrate;
A multi-layer metal foil having a plurality of peelable metal layers;
Have
The semi-cured with an insulating resin material of the insulating resin, the laminated board, wherein Rukoto having a structure that covers the integral outer peripheral portion of the metal foil of the multilayer structure. A semi-cured insulating resin sheet is stacked on the outside of the support substrate, and the outer surface of the semi-cured insulating resin sheet is smaller in size than the semi-cured insulating resin sheet, and a plurality of metal layers are laminated on both sides in a peelable manner. Laminating the laminated metal sheet with the ultra-thin copper foil layer on the outside,
When laminating the first interlayer insulating resin layer on the outside of the laminated metal sheet, the insulating resin of the interlayer insulating resin layer flows out onto the surface of the outer edge portion of the metal foil of the multilayer structure, whereby the insulating resin causes the Forming a laminated substrate covering the outer peripheral portion of the metal foil having a multilayer structure ;
Forming a via hole pilot hole reaching the laminated metal sheet of the laminated metal sheet by a laser beam for drilling from the outside of the interlayer insulating resin layer;
Forming a first via hole filled with the via hole prepared hole by copper plating and a land of the first via hole and a first wiring pattern outside the first interlayer insulating resin layer;
Forming a multilayer wiring structure by alternately laminating a next interlayer insulating resin layer and a wiring pattern layer outside the first interlayer insulating resin layer and the first wiring pattern;
Separating the multilayer wiring structure from the support substrate by peeling the laminated metal sheet; and
Quick etching of the ultra-thin copper foil layer of the multilayer wiring structure exposes the upper base of the frustoconical via hole embedded in the interlayer insulating resin layer to have a lower base diameter smaller than the lower base diameter And a step of forming the multilayer wiring board.

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