JP2013047673A - Method for manufacturing laminate, laminate, printed wiring board, semiconductor device, and resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a material obtained by reducing bubbles (voids) included in a laminate and to provide the material to a market.SOLUTION: This invention is concerned with a manufacturing method for manufacturing a laminate including no bubbles with a diameter of 30 μm and more by an inspection using an X-ray camera. Further this invention is concerned with a manufacturing method for more easily performing measurement using the X-ray camera and inexpensively and simply manufacturing the laminate by uniformly dispersing and mixing an X-ray contrast medium into a resin composition for the laminate. Further this invention is concerned with a laminate, a printed wiring board, multilayer printed wiring board, and a semiconductor device to be manufactured by utilizing these manufacturing methods.

Description

  The present invention relates to a method for manufacturing a laminate, a laminate, a printed wiring board, a semiconductor device, and a resin composition.

  2. Description of the Related Art In recent years, with the demand for higher functionality of electronic devices and the like, electronic components have been integrated at a high density and further at a high density mounting. For this reason, printed wiring boards and the like for high-density mounting used for these are becoming smaller and thinner and higher in density than ever before. In particular, when the wiring density is increased, the thickness of the copper wiring formed becomes extremely thin, such as several tens of microns. Therefore, it is possible to produce a printed wiring board resin substrate having smoothness and uniformity enough to form a fine wiring. Required.

  However, printed wiring boards and laminates are generally composites of resins, glass cloths, and various fillers, and have a composition that easily generates non-uniformity and voids of several microns to several tens of microns. Advanced production technology is required to produce a product with good properties and uniformity. In particular, voids or bubbles of the above sizes are likely to be generated and difficult to eradicate, and may hinder the formation of fine wiring.

Therefore, technologies relating to printed wiring boards and the like using various bubble reduction techniques and manufacturing methods thereof are disclosed. For example, a method of detecting with an optical microscope using a fluorescent solution has been proposed (see, for example, Patent Document 1).
However, in this method, it is necessary to remove the copper foil, that is, to perform a destructive test in order to detect bubbles. It was unsuitable for quality inspection of all the products of the laminate before removing the copper foil.

Japanese Patent No. 3577801

  An object of the present invention is to provide a method for producing a printed wiring board without bubbles by devising a measurement method and a formulation, thereby providing a printed wiring board, a laminate, and a prepreg. Furthermore, the present invention provides a semiconductor device using the same and a resin composition used therefor.

The object of the present invention is achieved by the present invention described in the following (1) to (16).
(1) Fabrication of a laminated plate in which a fiber base material is impregnated with a resin composition to prepare a prepreg, and then a metal foil is laminated on at least one surface of a laminate in which at least one prepreg is laminated. A method for confirming that bubbles of a predetermined size or larger are not included by observation using an X-ray camera, and in the case where the presence of bubbles of a predetermined size or larger is confirmed, the step of making this a defective product The manufacturing method of the laminated board characterized by including.
(2) The method for producing a laminated board according to (1), wherein the bubbles having a predetermined dimension or more are bubbles having a size of 30 μm or more.
(3) The method for producing a laminated board according to (1) or (2), wherein the resin composition contains a resin and a contrast agent for X-rays.
(4) The method for producing a laminated board according to (3), wherein the X-ray contrast medium contains barium sulfate particles.
(5) The method for producing a laminated board according to (4), wherein the barium sulfate has an average particle size of 3 μm or less.
(6) The content of the X-ray contrast medium is 0.5% by mass or more and 70% by mass or less of the entire resin composition, and any one of (3) to (5) The manufacturing method of the laminated board as described in a term.
(7) The method for producing a laminated board according to any one of (3) to (6), wherein the resin includes an epoxy resin.
(8) The method for producing a laminated board according to any one of (3) to (7), wherein the resin further contains a cyanate resin.
(9) The method for producing a laminated board according to any one of (3) to (8), wherein the resin further contains a phenol resin.
(10) The method for producing a laminated board according to any one of (1) to (9), wherein the resin composition further contains an inorganic filler.
(11) The method for producing a laminated board according to (10), wherein the inorganic filler has an average particle size of 0.3 μm or more and 5 μm or less.
(12) Content of the said inorganic filler is 20 mass% or more and 85 mass% or less of the said whole resin composition, The manufacturing method of the laminated board as described in (10) or (11) characterized by the above-mentioned.
(13) A laminate produced by using the laminate production method according to any one of (1) to (12).
(14) A multilayer or single-layer printed wiring board comprising the laminated board according to (13).
(15) A semiconductor device comprising a semiconductor element mounted on the printed wiring board according to (14).
(16) After producing a prepreg by impregnating a fiber base material with a resin composition, when obtaining a laminate by laminating metal foil on at least one side of a laminate in which at least one prepreg is laminated, X When it is confirmed by observation using a line camera that bubbles of a predetermined size or larger are not included, and the presence of bubbles of the predetermined size or larger is confirmed, it is used for manufacturing a laminate having this as a defective product. A resin composition comprising a resin and an X-ray contrast medium.

  According to the present invention, it is possible to manufacture a printed wiring board or a laminated board from which bubbles, particularly bubbles having a diameter of 30 μm or more are eliminated, and a high-quality semiconductor device or electronic product can be obtained.

It is a block diagram which shows typically the basic composition of the X-ray camera used for the manufacturing method of the laminated sheet of this patent. It is a block diagram which shows typically the structure of the X-ray camera apparatus used in the Example.

  Hereinafter, the manufacturing method of the laminated board of this invention, a laminated board, a printed wiring board, a semiconductor device, and a resin composition are demonstrated.

  In the method for producing a laminate of the present invention, a fiber base material is impregnated with a resin composition to prepare a prepreg, and then a metal foil is laminated on at least one side of a laminate in which at least one prepreg is laminated. A method for producing a laminated board for obtaining a plate, confirming that bubbles of a predetermined size or more are not included by observation using an X-ray camera, and if the presence of bubbles of a predetermined size or more is confirmed, It is a manufacturing method of the laminated board characterized by including the process which makes this inferior goods. Moreover, it can be set as the manufacturing method of the laminated board characterized by the bubble of 30 micrometers or more not existing.

In addition, the production of a laminate capable of removing defective products due to air bubbles by blending an X-ray contrast agent in the resin composition to improve the sensitivity of the X-ray camera and make air bubbles easier to detect. It can be a method.
The laminate of the present invention is a laminate produced by using the above production method, and is a laminate in which at least one prepreg is laminated, and has a metal foil on at least one side. is there.

Moreover, the multilayer printed wiring board of the present invention is characterized in that it is manufactured using the above-described manufacturing method using the prepreg as an insulating layer, using the above-described laminated board as an inner layer circuit board. Can do.
The semiconductor device of the present invention is characterized in that a semiconductor element is mounted on the printed wiring board described above.
In addition, the resin and the resin composition of the present invention are characterized in that they are used for laminated boards, printed wiring boards, and semiconductor devices manufactured by using the manufacturing method described above.

(Laminate production method)
First, the manufacturing method of a laminated board is demonstrated in detail.
After a resin substrate (described later) is impregnated into a fiber substrate (described later) to prepare a prepreg (described later), a laminate in which a metal foil is laminated on at least one side of a laminate in which at least one prepreg is stacked is used as a laminate. Define. And in addition to obtaining the said process, the manufacturing method of the laminated board of this invention confirms that the bubble beyond a predetermined dimension is not contained by observation using the X-ray camera mentioned later, The said predetermined dimension When the presence of the above bubbles is confirmed, the method includes a step of making this a defective product. The ability to detect bubbles with an X-ray camera can take as many detailed images as possible without considering the measurement speed. However, judging from the wiring width of a copper wiring formed on a printed wiring board, which will be described later, it is judged that it is not necessary to detect air bubbles having a diameter of less than 1 μm, so detection of air bubbles having a diameter of 1 μm or more is an inspection object. In addition, since the defect of the copper wiring on the printed wiring board increases as the bubble diameter increases, it is desirable to eliminate at least completely the large bubbles of 30 μm or more in diameter, more desirably 10 μm or more, and even more desirably 5 μm or more. It is desirable to eliminate it completely.

(X-ray camera)
Next, the bubble detection method by the X-ray camera in the manufacturing method of the laminated board of this invention is demonstrated in detail.
The X-ray camera used in the method for manufacturing a laminated plate of this patent refers to an apparatus that includes an X-ray source, an X-ray sensor, and an image processing apparatus as essential elements. A basic configuration diagram is shown in FIG. This is a schematic illustration of the basic components and their connections, and is not limited to this. Here, 1 is an X-ray source, 2 is an X-ray sensor, 3 is a sample, that is, a printed wiring board or laminate to be evaluated, 4 is a conveying device, 5 is an image processing device, 6 is a control device, and 7 is a marking device for a defective portion. , 8 indicate X-rays, and dotted lines in the figure indicate wirings connecting the devices. A mechanism in which X-rays are irradiated while a sample is being transported by a transport device, the transmitted light of the sample is detected by an X-ray sensor, the data is analyzed by an image processing device, and a marking device is used to mark where bubbles are present It is. It is desirable that all the movements are interlocked and controlled by the control device.

An X-ray source refers to a device that generates X-rays as a light source. The X-ray source is not particularly limited as long as it is an apparatus that generates X-rays, and the output and the format are not particularly limited. For example, an electron gun X-ray source, a field emission electron gun X-ray source, a microfocus X-ray source, a pulse X-ray source, a commercially available tabletop radiation source, and a small industrial X-ray source having a micro electron storage ring , Etc. in the form of an X-ray source. Since it is necessary to magnify and image, an X-ray source that can emit X-rays from as small a light source as possible is more desirable.

  An X-ray sensor refers to a sensor that digitizes or visualizes an X-ray image. X-rays emitted from the X-ray source are irradiated to a target sample to be observed, that is, a printed wiring board, and used to detect transmitted X-rays. There is no particular limitation as long as it is a device or the like having a function of digitizing or visualizing transmitted X-rays. For example, a CMOS sensor, an electron multiplier, a CCD sensor, and the like can be given. Or speaking of the difference in shape, an X-ray sensor having a shape such as a line type sensor, a flat panel sensor, or a microchannel plate is used. It should be noted that high-speed processing is possible, digital processing is possible, and pixel processing is possible in order to detect small bubbles with a size of 30 μm or more, preferably 10 μm or more, more preferably 5 μm or more in a large area sample at high speed. It is more desirable to use a device with a small size.

  The image processing apparatus indicates a general apparatus having a function of determining where a bubble is from a numerical value or an image obtained from an X-ray sensor. A function for determining the presence / absence of bubbles in the portion from the numerical value obtained by the X-ray sensor is required. For example, it is necessary to have a function of binarizing an image obtained by an X-ray sensor and performing bubble detection. Further, since it is necessary to inspect a large number of printed wiring boards, it is desirable that the apparatus process a large area at high speed. A device that satisfies the above conditions is not particularly limited, whether it is a dedicated device or a personal computer.

  The device for marking a defective portion refers to a device for performing a treatment such as marking or punching a portion where there is a bubble based on a result determined by the above image processing. Based on the mark attached to this device, it is possible to select and ship only parts that are not defective later. In this patent, this device is not an indispensable device, but it is an indispensable device when air bubbles are to be detected automatically at high speed.

  The control device is a device for controlling the X-ray source, the conveyance device, the X-ray sensor, the image processing device, the device for marking a defective portion, and the like, and enabling them to detect bubbles by linking them. In this patent, this device is not an essential device. However, when air bubbles are to be detected automatically at high speed, the use of a control device is essential for improving the detection speed. Any device capable of optimally controlling the movement of the device is not particularly limited, whether it is a dedicated device or a personal computer.

  The conveying device refers to all devices that convey a sample, that is, a printed wiring board or a laminated board. Although this device is not an essential device in this patent, it is considered that it is preferably used when air bubbles are detected at high speed with high accuracy. The shape is not particularly limited as long as the sample can be conveyed, but the shape may be a belt conveyor type or a tray conveyance method. In addition, in order to deliver X-rays that have passed through the sample to the X-ray sensor below the belt, in the case of the belt conveyor type, a material that can transmit X-rays well can be selected. Or, it is necessary to devise such that the parts to be inspected are transported without a belt or tray. In addition, the place to inspect by irradiating with X-rays and the device that marks the defective part after that must be installed a little apart in many cases. Therefore, the movement of the transfer device including the transfer speed of the transfer device etc. It is possible to mark an accurate bubble position only by being controlled by the control device.

(Contrast agent for X-ray)
Next, an X-ray contrast agent is a compound that is blended into a resin composition in order to increase the contrast between a bubbled portion and a bubble-free portion in imaging with X-rays and increase the detection capability. It is necessary that the substance has a relatively high shielding effect against X-rays. The content is not particularly limited as long as the material has the above characteristics, but barium sulfate and various iodinated organic compounds such as triiodinated phenol, triiodinated benzene, triiodinated benzoic acid and salts thereof are also used. In addition, various metal particles such as gold particles, silver particles, and copper particles can be used. Barium sulfate particles are most preferably used because of the influence of X-ray shielding performance, price, stability, electrical characteristics, and the like.

  The blending amount of the contrast agent is not particularly limited, but more preferably 0.5% by mass or more and 70% by mass or less of the entire resin composition, and preferably 3% by mass or more and 50% by mass or less. More desirable. If it is less than the above lower limit value, the contrast increase in the target X-ray image is insufficient, and if it exceeds the above upper limit value, the filling property and electrical characteristics as the resin composition are lowered.

  The average particle diameter, the maximum particle diameter, and the minimum particle diameter in the barium sulfate most preferably used as a contrast agent are not particularly limited, but it is desirable that the particle diameter is smaller than the size of the bubble to be evaluated. . In particular, it is more desirable that it is 1/10 or less of the size of the bubble to be evaluated. Therefore, the barium sulfate particles preferably have an average particle diameter of less than 3 μm, and more preferably 100 nm or less. Thereby, even when the blending amount of the contrast agent is small, the contrast can be increased and the detection capability can be increased. In addition, it is necessary to measure the average particle diameter with a dynamic light scattering particle size distribution meter or a laser light diffraction particle size distribution meter.

  Also, if the contrast agent is a particulate material, especially barium sulfate, there is a problem in using a material that has improved dispersibility in the material, such as by treating the surface of the contrast agent with an organic or inorganic material. There is no. Compounds used for the surface treatment include inorganic materials such as silica and alumina, and various silane coupling agents such as epoxy silane, styryl silane, methacryloxy silane, acryloxy silane, mercapto silane, N-butylaminopropyltrimethoxy. Silane, N-ethylaminoisobutyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3- (N-allylamino) propyltrimethoxysilane, (cyclohexylaminomethyl) tri Ethoxysilane, N-cyclohexylaminopropyltrimethoxysilane, N-ethylaminoisobutylmethoxyldiethoxysilane, (phenylaminomethyl) methyldimethoxysilane, N-phenylaminomethyltrieth Shishiran, N- methyl aminopropyl methyl dimethoxy silane, vinyl silane, isocyanate silane, Surufidoshiran, chloropropyl silane, raised organic material such as ureido silane compound is not particularly limited.

(Resin composition)
Next, the resin composition used for the manufacturing method of the laminated board of this invention is demonstrated in detail.
The resin composition contains a resin such as an epoxy resin in addition to the above X-ray contrast agent. Thereby, the laminated board excellent in an electrical property can be obtained.

Although it does not specifically limit as resin used for the said resin composition, It is possible to mix | blend an epoxy resin. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol Z type epoxy resin (4,4′-cyclohexyldiene bisphenol type epoxy resin), Bisphenol P type epoxy resin (4,4 '-(1,4) -phenylenediisopridiene) bisphenol type epoxy resin), bisphenol M type epoxy resin (4,4'-(1,3-phenylenediisopridiene) ) Bisphenol type epoxy resin), phenol novolak type epoxy resin, cresol novolak type epoxy resin, etc., biphenyl type epoxy resin, xylylene type epoxy resin, phenol aralkyl Type epoxy resin, biphenyl aralkyl type epoxy resin, biphenyl dimethylene type epoxy resin, trisphenol methane novolak type epoxy resin, glycidyl ethers of 1,1,2,2- (tetraphenol) ethane, trifunctional or tetrafunctional Glycidylamines, arylalkylene type epoxy resins such as tetramethylbiphenyl type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin And fluorene type epoxy resin. One of these can be used alone, two or more having different weight average molecular weights can be used in combination, and one or two or more thereof and their prepolymers can be used in combination.

  Among these epoxy resins, at least one selected from the group consisting of biphenyldimethylene type epoxy resins, novolac type epoxy resins, naphthalene-modified cresol novolac epoxy resins, and anthracene type epoxy resins is particularly preferable. Thereby, moisture absorption solder heat resistance and a flame retardance can be improved.

  Although content of the said epoxy resin is not specifically limited, It is preferable to set it as 5 to 60 mass% of the said whole resin composition. If the content is less than the lower limit, the curability of the resin composition may be lowered, or the moisture resistance of the prepreg or multilayer printed wiring board obtained from the resin composition may be lowered. Moreover, when the said upper limit is exceeded, the linear thermal expansion coefficient of a prepreg or a multilayer printed wiring board may become large, or heat resistance may fall. The content of the epoxy resin is preferably 10% by mass or more and 50% by mass or less based on the entire resin composition.

The weight average molecular weight of the epoxy resin is not particularly limited, but is preferably 1.0 × 10 ² or more and 2.0 × 10 ⁴ or less. When the weight average molecular weight is less than the lower limit value, tackiness may occur on the surface of the insulating resin layer, and when the upper limit value is exceeded, solder heat resistance may decrease. By setting the weight average molecular weight within the above range, it is possible to achieve an excellent balance of these characteristics. In addition, the weight average molecular weight of the said epoxy resin can be measured by GPC, for example.

  Although it does not specifically limit as said epoxy resin, The thing which does not contain a halogen atom substantially is preferable. Here, “substantially free of halogen atoms” means that, for example, halogen derived from a halogen-based component used in the epoxy resin synthesis process remains in the epoxy resin even after the halogen removal step. It means to allow. Taking an epoxy resin as an example, it is usually preferable that the epoxy resin does not contain a halogen atom exceeding 30 ppm.

  Moreover, although the said resin composition is not specifically limited, Cyanate resin can also be used. Moreover, it is more preferable that cyanate resin is further included in addition to the use of epoxy resin. Thereby, a flame retardance can be improved more. Although the said cyanate resin is not specifically limited, For example, it can obtain by making a halogenated cyanide compound and phenols react, and prepolymerizing by methods, such as a heating, as needed. Moreover, the commercial item prepared in this way can also be used.

  Although it does not specifically limit as a kind of said cyanate resin, For example, bisphenol-type cyanate resin, such as a novolak-type cyanate resin, bisphenol A-type cyanate resin, bisphenol E-type cyanate resin, tetramethylbisphenol F-type cyanate resin, etc. can be mentioned. .

The cyanate resin preferably has two or more cyanate groups (—O—CN) in the molecule. For example, 2,2′-bis (4-cyanatophenyl) isopropylidene, 1,1′-bis (4-cyanatophenyl) ethane, bis (4-cyanato-3,5-dimethylphenyl) methane, 3-bis (4-cyanatophenyl-1- (1-methylethylidene)) benzene, dicyclopentadiene type cyanate ester, phenol novolac type cyanate ester, bis (4-cyanatophenyl) thioether, bis (4-cyanato) Phenyl) ether, 1,1,1-tris (4-cyanatophenyl) ethane, tris (4-cyanatophenyl) phosphite, bis (4-cyanatophenyl) sulfone, 2,2-bis (4-si Anatophenyl) propane, 1,3-, 1,4-, 1,6-, 1,8-, 2,6- or 2
, 7-dicyanatonaphthalene, 1,3,6-tricyanatonaphthalene, 4,4′-dicyanatobiphenyl, and phenol novolak-type and cresol novolak-type polyhydric phenols and obtained by reaction with cyanogen halide Examples include cyanate resins. Among these, phenol novolac-type cyanate resin is excellent in flame retardancy and low thermal expansion, and 2,2′-bis (4-cyanatophenyl) isopropylidene and dicyclopentadiene-type cyanate ester control the crosslinking density. And excellent in moisture resistance reliability. In particular, a phenol novolac type cyanate resin is preferred from the viewpoint of low thermal expansion. Furthermore, other cyanate resins may be used alone or in combination of two or more, and are not particularly limited.

  The said cyanate resin may be used independently, can also use together cyanate resin from which a weight average molecular weight differs, or can also use together the said cyanate resin and its prepolymer. The prepolymer is usually obtained by, for example, trimerizing the cyanate resin by a heat reaction or the like, and is preferably used for adjusting the moldability and fluidity of the resin composition. Although the prepolymer is not particularly limited, for example, when a prepolymer having a trimerization rate of 20 to 50% by mass is used, good moldability and fluidity can be expressed.

  Although content of the said cyanate resin is not specifically limited, It is preferable that it is 5-60 mass% of the whole resin composition. More preferably, it is 10-50 mass%. Thereby, cyanate resin can express heat resistance and a flame retardance effectively. If the content of the cyanate resin is less than the lower limit value, the thermal expansibility increases and the heat resistance may decrease, and if the content exceeds the upper limit value, the strength of the prepreg using the resin composition may decrease. . The content of the cyanate resin is particularly preferably 10 to 40% by mass in the resin composition.

  Although it does not specifically limit as resin used for the said resin composition, A phenol resin can also be used. The phenol resin can be used alone, or can be used as a curing agent in an epoxy resin or a combination resin of an epoxy resin and a cyanate resin. As the phenolic curing agent, known or commonly used phenolic novolac resins, alkylphenol novolac resins, bisphenol A novolac resins, dicyclopentadiene type phenol resins, zyloc type phenol resins, terpene modified phenol resins, polyvinylphenols, etc. Can be used in combination.

  Although the compounding quantity of the said phenol hardening agent is not specifically limited, The equivalent ratio (phenolic hydroxyl group equivalent / epoxy group equivalent) with an epoxy resin is less than 1.0 and 0.1 or more are preferable. As a result, there remains no unreacted phenol curing agent, and the moisture absorption heat resistance is improved. Furthermore, when severe moisture absorption heat resistance is required, the range of 0.2 to 0.5 is particularly preferable. This is because the phenolic resin not only acts as a curing agent, but can promote curing of cyanate groups and epoxy groups.

Apart from the contrast agent, the resin composition can also contain other inorganic fillers. Thereby, low thermal expansion property, heat resistance, and drill workability can be improved. Examples of inorganic fillers include silica (amorphous or crystalline silica, or spherical or crushed silica), zinc borate, talc, alumina, aluminum hydroxide, magnesium hydroxide, boehmite (alumina monohydrate obtained by modifying gibbsite) ), Titania, zirconia, silicon nitride, aluminum nitride, boron nitride and the like. Among these, amorphous spherical silica, aluminum hydroxide, and boehmite are preferable. Moreover, there is no problem in using a plurality of these inorganic fillers in combination. Thereby, the low thermal expansion coefficient of the resin composition, the heat resistance improvement, and the drill workability can be improved. The average particle diameter of the inorganic filler is not particularly limited, but is preferably 0.3 to 5 μm, and particularly preferably 0.5 to 3 μm. When the average particle size is within the above range, the high filling property and fluidity are particularly excellent. The average particle diameter of the inorganic filler can be measured by a laser diffraction scattering method. Specifically, the average particle diameter of the inorganic filler is defined by D50. The content of the inorganic filler is not particularly limited, but is preferably 20 to 85% by mass, and particularly preferably 25 to 75% by mass, based on the entire resin composition. When the content is in the above range, the balance between heat resistance and fluidity is particularly excellent.

  The inorganic filler (especially silica) may be used after surface treatment with functional group-containing silanes and / or alkylsilazanes in advance. By applying the surface treatment in advance, aggregation of the inorganic filler can be suppressed and the resin composition of the present invention can be favorably dispersed. Known functional group-containing silanes such as the functional group-containing silanes and / or alkylsilazanes can be used. For example, epoxy silane, styryl silane, methacryloxy silane, acryloxy silane, mercapto silane, N-butylaminopropyltrimethoxysilane, N-ethylaminoisobutyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N-phenyl-3 -Aminopropyltrimethoxysilane, 3- (N-allylamino) propyltrimethoxysilane, (cyclohexylaminomethyl) triethoxysilane, N-cyclohexylaminopropyltrimethoxysilane, N-ethylaminoisobutylmethoxyldiethoxysilane, (phenylamino Methyl) methyldimethoxysilane, N-phenylaminomethyltriethoxysilane, N-methylaminopropylmethyldimethoxysilane, vinyl silane, isocyanate silane Surufidoshiran, chloropropyl silane, can be cited ureido silane compounds. Examples of the alkylsilazanes include hexamethyldisilazane (HMDS), 1,3-divinyl-1,1,3,3-tetramethyldisilazane, octamethyltrisilazane, hexamethylcyclotrisilazane, and the like. it can. Among these, hexamethyldisilazane (HMDS) is preferable as the alkylsilazanes.

  The amount of the functional group-containing silanes and / or alkylsilazanes to be surface-treated in advance on the inorganic filler (especially silica) is not particularly limited, but is 0.01 parts by mass with respect to 100 parts by mass of the third inorganic filler. The amount is preferably 5 parts by mass or less. More preferably, it is 0.1 to 3 parts by mass. When the content of the coupling agent exceeds the upper limit value, cracks may occur in the insulating layer during the production of the multilayer printed wiring board, and when the content is less than the lower limit value, the resin component and the third inorganic filler are bonded. The power may be reduced. In addition, a method for subjecting the inorganic filler (particularly silica) to surface treatment with a functional group-containing silane and / or alkylsilazane is not particularly limited, but a wet method or a dry method is preferable. The wet method is particularly preferable. When compared with the dry method, the wet method can uniformly treat the surface of the third inorganic filler.

  If necessary, the resin composition may contain additives other than the above components as long as the characteristics are not impaired. Examples of the components other than the above components include curing accelerators such as imidazoles, triphenylphosphine, and quaternary phosphonium salts, surfactants such as acrylates, colorants such as dyes, and pigments. .

(Prepreg)
Next, the prepreg used for the manufacturing method of the laminated board of this invention is demonstrated.
The prepreg used in the method for producing a laminate of the present invention is obtained by impregnating a fiber base material with the above resin composition. Thereby, the prepreg excellent in heat resistance, low expansibility, and a flame retardance can be obtained. Examples of the base material include glass fiber base materials such as glass woven fabric, glass non-woven fabric, and glass paper, woven fabric and non-woven fabric made of synthetic fibers such as paper, aramid, polyester, aromatic polyester, and fluororesin, and metal fibers. Woven fabrics, nonwoven fabrics, mats and the like made of carbon fibers, mineral fibers, and the like. These substrates may be used alone or in combination. Among these, a glass fiber base material is preferable. Thereby, the rigidity and dimensional stability of a prepreg can be improved.

  Examples of the method of impregnating the base material with the resin composition include a method of immersing the base material in a resin varnish, a method of applying with various coaters, and a method of spraying with a spray. Among these, the method of immersing the base material in the resin varnish is preferable. Thereby, the impregnation property of the resin composition with respect to a base material can be improved. In addition, when a base material is immersed in a resin varnish, a normal impregnation coating equipment can be used.

  The solvent used in the resin varnish desirably has good solubility in the resin composition, but a poor solvent may be used as long as it does not adversely affect the resin varnish. Examples of the solvent exhibiting good solubility include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like. The solid content of the resin varnish is not particularly limited, but the solid content of the resin composition is preferably 30 to 80% by mass, and particularly preferably 40 to 70% by mass. Thereby, the impregnation property to the base material of the resin varnish can be improved. A prepreg can be obtained by impregnating the base material with the resin composition and drying at a predetermined temperature, for example, 90 to 180 ° C.

(Laminated board)
Next, the laminated board of this invention is demonstrated.
The laminate of the present invention has a metal foil on at least one side of a laminate obtained by superposing at least one prepreg. Thereby, the laminated board excellent in heat resistance, low expansibility, and a flame retardance can be obtained. When one prepreg is used, the metal foil is overlapped on both the upper and lower surfaces or one surface. Two or more prepregs can be laminated. When two or more prepregs are laminated, a metal foil or film is laminated on the outermost upper and lower surfaces or one surface of the laminated prepreg. Next, a laminate can be obtained by heat-pressing a laminate of a prepreg and a metal foil.

Although the temperature to heat is not specifically limited, 120-220 degreeC is preferable and especially 150-200 degreeC is preferable. Although the pressure to pressurize is not particularly limited, it is preferably 1.5 to 5 MPa, and particularly preferably 2 to 4 MPa. Moreover, it is 150-30 with high temperature soot as needed.
Post-curing may be performed at a temperature of 0 ° C.

(Multilayer printed wiring board)
Next, the multilayer printed wiring board of the present invention will be described.
The multilayer printed wiring board of the present invention uses the prepreg described above as an insulating layer. Moreover, the multilayer printed wiring board of this invention can use the laminated board as described above for an inner-layer circuit board.

  Below, the case where the said laminated board is used as an inner-layer circuit board is demonstrated. A circuit is formed on one side or both sides of the laminated board to be the inner circuit board. In some cases, through holes can be formed by drilling or laser processing, and electrical connection on both sides can be achieved by plating or the like. A commercially available resin sheet or the prepreg of the present invention is superimposed on the inner layer circuit board and heat-press molded to obtain a multilayer printed wiring board.

  Specifically, the insulating layer side of the resin sheet and the inner layer circuit board are combined, vacuum-pressed using a pressure-pressing laminator, etc., and then the insulating layer is heat-cured with a hot-air dryer or the like. Can be obtained. Although it does not specifically limit as conditions to heat-press form here, If an example is given, it can implement at the temperature of 60-160 degreeC, and the pressure of 0.2-3 MPa. Moreover, it is although it does not specifically limit as conditions to heat-harden, If an example is given, it can implement in temperature 140-240 degreeC and time 30-120 minutes.

  Further, the prepreg can be obtained by superimposing the prepreg on the inner circuit board and heating and pressing it with a flat plate press or the like. Although it does not specifically limit as conditions to heat-press form here, For example, it can implement at the temperature of 140-240 degreeC, and the pressure of 1-4 MPa. In the heat and pressure forming by such a flat plate press apparatus or the like, the insulating layer is heat-cured simultaneously with the heat and pressure forming.

  The method of manufacturing the multilayer printed wiring board includes a step of continuously laminating the resin sheet or prepreg on the surface of the inner layer circuit board on which the inner layer circuit pattern is formed and a step of forming a conductor circuit layer by a semi-additive method. Including.

  Curing of the insulating layer formed from the resin sheet or the prepreg may be left in a semi-cured state in order to facilitate the subsequent laser irradiation and removal of the resin residue and improve desmearability. In addition, the first insulating layer is partially cured (semi-cured) by heating at a temperature lower than the normal heating temperature, and one or more insulating layers are further formed on the insulating layer to form a semi-cured insulating layer. The adhesiveness between the insulating layer and the insulating layer and the circuit can be improved by heating and curing again to such an extent that there is no practical problem. The semi-curing temperature in this case is preferably 80 ° C to 200 ° C, more preferably 100 ° C to 180 ° C. In the next step, laser is irradiated to form an opening in the insulating layer, but it is necessary to peel off the substrate before that. There is no particular problem with the peeling of the base material either after the insulating layer is formed, before heat curing, or after heat curing.

  The inner layer circuit board used when obtaining the multilayer printed wiring board is preferably, for example, that a predetermined conductor circuit is formed by etching or the like on both surfaces of a copper clad laminate and the conductor circuit portion is blackened. Can be used.

  Next, the insulating layer is irradiated with laser to form an opening. As the laser, an excimer laser, a UV laser, a carbon dioxide gas laser, or the like can be used.

  Resin residues after laser irradiation are preferably removed with an oxidizing agent such as permanganate or dichromate. Further, the surface of the smooth insulating layer can be simultaneously roughened, and the adhesion of the conductive wiring circuit formed by subsequent metal plating can be improved.

  Next, an outer layer circuit is formed. The outer layer circuit is formed by connecting the insulating resin layers by metal plating and forming an outer layer circuit pattern by etching. A multilayer printed wiring board can be obtained in the same manner as when a resin sheet or prepreg is used.

  When a resin sheet having a metal foil or a prepreg is used, the circuit may be formed by etching for use as a conductor circuit without peeling off the metal foil. In that case, if an insulating resin sheet with a base material using a thick copper foil is used, it becomes difficult to make a fine pitch in subsequent circuit pattern formation, so use an ultrathin copper foil of 1 to 5 μm, or 12 to 18 μm. In some cases, the copper foil is half-etched to a thickness of 1 to 5 μm by etching.

  Further, an insulating layer may be stacked and a circuit may be formed in the same manner as described above. However, in the design of the multilayer printed wiring board, a solder resist is formed on the outermost layer after the circuit is formed. The method of forming the solder resist is not particularly limited. For example, a method of laminating (laminating) a dry film type solder resist, forming by exposure and development, or forming a printed liquid resist by exposure and development It is done by the method to do. In addition, when using the obtained multilayer printed wiring board for a semiconductor device, the electrode part for a connection is provided in order to mount a semiconductor element. The connection electrode portion can be appropriately coated with a metal film such as gold plating, nickel plating, or solder plating. A multilayer printed wiring board can be manufactured by such a method.

(Semiconductor device)
Next, the semiconductor device of the present invention will be described. A semiconductor element having solder bumps is mounted on the multilayer printed wiring board obtained as described above, and connection with the multilayer printed wiring board is attempted through the solder bumps. A liquid sealing resin is filled between the multilayer printed wiring board and the semiconductor element to form a semiconductor device. The solder bump is preferably made of an alloy made of tin, lead, silver, copper, bismuth or the like.

  The connection method between the semiconductor element and the multilayer printed wiring board is to align the connection electrode part on the substrate with the solder bump of the semiconductor element using a flip chip bonder, etc. The solder bumps are heated to the melting point or higher by using a heating device, and the multilayer printed wiring board and the solder bumps are connected by fusion bonding. In order to improve connection reliability, a metal layer having a relatively low melting point such as solder paste may be formed in advance on the connection electrode portion on the multilayer printed wiring board. Prior to this bonding step, the connection reliability can be improved by applying a flux to the solder bumps and / or the surface layer of the connection electrode portion on the multilayer printed wiring board.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example and a comparative example, this invention is not limited to this.

Example 1
(1) Preparation of resin varnish Novolak type epoxy resin (EOCN-1020-75, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 200) as epoxy resin, 17.5 parts by mass, boehmite (manufactured by Kawai Lime Co., product number) as inorganic filler BMT-3L, 61.9 parts by mass of an average particle size of 2.9 μm, 1% thermal decomposition temperature of 420 ° C., and 3.0 parts by mass of spherical nano silica (product number NSS-5N, manufactured by Tokuyama, average particle size of 70 nm) 17.5 parts by mass of a phenol resin (MEH7851-4L, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 187) as a curing agent, and 0.1 parts by mass of imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number 2E4MZ) as a curing accelerator, Dissolved and mixed in isobutyl ketone. Subsequently, it stirred using the high-speed stirring apparatus and prepared the resin varnish.

(2) Preparation of prepreg The resin varnish was impregnated into a glass woven fabric (thickness 94 μm, Nittobo E glass woven fabric, WEA-2116), dried in a heating furnace at 150 ° C. for 2 minutes, and varnish in the prepreg A prepreg having a solid content of about 50% by mass was obtained.

(3) Preparation of laminated board Two sheets of the prepreg are stacked, 12 μm copper foil (3EC-VLP foil manufactured by Mitsui Mining & Smelting Co., Ltd.) is stacked on both sides, and pressure-molded at a pressure of 3 MPa and a temperature of 220 ° C. for 2 hours. A laminate having a copper foil on both sides with a thickness of 0.21 mm was obtained.

(4) Inspection by X-ray camera The laminate was evaluated by an X-ray camera. A 130 kV sealed X-ray source L9181-02 manufactured by Hamamatsu Photonics was used, and C10650 was also used as the line sensor. The experimental X-ray camera apparatus shown in FIG. 2 was used. The size of the measured laminate was 25 cm × 25 cm, and the measurement for four sheets was performed. The measurement magnification was 6 times. The line speed for conveying the laminate was 0.5 m / min. After measurement, it was binarized with a PC to detect bubbles. After extracting the part which seems to be a bubble on the screen and measuring the position accurately on the screen, the part corresponding to the position on the laminated plate was accurately marked, and then the part was cut and eliminated. By cutting and excluding the part having air bubbles, a laminate without air bubbles was obtained.

(5) Bubble inspection by destructive test The copper foil in the laminate was completely removed by etching, and the number and the number of bubbles of 30 μm or more were counted by optical microscope observation.

(Example 2)
(1) Preparation of resin varnish Novolak type epoxy resin (EOCN-1020-75, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 200) as epoxy resin, 17.5 parts by mass, boehmite (manufactured by Kawai Lime Co., product number) as inorganic filler BMT-3L, average particle size 2.9 μm, 1% pyrolysis temperature 420 ° C. 54.9 parts by mass, and barium sulfate nanoparticles (product number BF-1H, manufactured by Sakai Chemical, average particle size 100 nm) 10.0 parts by mass And 17.5 parts by mass of a phenol resin (MEH7851-4L, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 187) as a curing agent, and 0.1 parts by mass of imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number 2E4MZ) as a curing accelerator. And dissolved in methyl isobutyl ketone. Subsequently, it stirred using the high-speed stirring apparatus and prepared the resin varnish.
(2) The same operations as in Example 1 were performed with respect to the subsequent prepreg production, laminate production, X-ray camera inspection, and bubble inspection by destructive test. In addition, the bubble detection by an X-ray camera became easy to detect at each step | level by mix | blending the barium sulfate particle | grains of a contrast agent with the resin varnish, and it became possible to detect a finer void.

(Example 3)
(1) Preparation of resin varnish Novolak type epoxy resin (EOCN-1020-75, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 200) as epoxy resin, 17.5 parts by mass, boehmite (manufactured by Kawai Lime Co., product number) as inorganic filler BMT-3L, average particle size 2.9 μm, 1% thermal decomposition temperature 420 ° C. 54.9 parts by mass, and barium sulfate particles (product number W-1, Takehara Chemical Industries, average particle size 1.5 μm) 10 1.0 part by mass, 17.5 parts by mass of a phenol resin (MEH7851-4L, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 187) as a curing agent, and imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number 2E4MZ) 0.1 as a curing accelerator Part by mass was dissolved and mixed in methyl isobutyl ketone. Subsequently, it stirred using the high-speed stirring apparatus and prepared the resin varnish.
(2) The same operations as in Example 1 were performed with respect to the subsequent prepreg production, laminate production, X-ray camera inspection, and bubble inspection by destructive test.

Example 4
(1) Preparation of resin varnish Novolak type epoxy resin (EOCN-1020-75, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 200) as epoxy resin, 17.5 parts by mass, boehmite (manufactured by Kawai Lime Co., product number) as inorganic filler 34.9 parts by mass of BMT-3L, average particle size 2.9 μm, 1% thermal decomposition temperature 420 ° C.) and barium sulfate particles (Part No. W-1, Takehara Chemical Industries, average particle size 1.5 μm) 30 1.0 part by mass, 17.5 parts by mass of a phenol resin (MEH7851-4L, manufactured by Meiwa Kasei Co., Ltd., hydroxyl equivalent 187) as a curing agent, and imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number 2E4MZ) 0.1 as a curing accelerator Part by mass was dissolved and mixed in methyl isobutyl ketone. Subsequently, it stirred using the high-speed stirring apparatus and prepared the resin varnish.
(2) The same operations as in Example 1 were performed with respect to the subsequent prepreg production, laminate production, X-ray camera inspection, and bubble inspection by destructive test.

(Example 5)
(1) Preparation of resin varnish 17.5 parts by mass of a novolak type epoxy resin (EOCN-1020-75, Nippon Kayaku Co., Ltd., epoxy equivalent 200) as an epoxy resin, and barium sulfate particles (product number) as an inorganic filler and contrast agent W-1, Takehara Chemical Industry Co., Ltd., average particle diameter 1.5 μm) 64.9 parts by mass, and 17.5 parts by mass of a phenolic resin (MEH7851-4L, Meiwa Kasei Co., Ltd., hydroxyl equivalent 187) as a curing agent Then, 0.1 part by mass of imidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., product number 2E4MZ) as a curing accelerator was dissolved and mixed in methyl isobutyl ketone. Subsequently, it stirred using the high-speed stirring apparatus and prepared the resin varnish.
(2) The same operations as in Example 1 were performed with respect to the subsequent prepreg production, laminate production, X-ray camera inspection, and bubble inspection by destructive test.

(Comparative Example 1)
The same operations as in Example 1 were performed until adjustment of the resin varnish, preparation of the prepreg, and preparation of the laminated plate. Thereafter, the inspection by the X-ray camera was omitted, and the bubble inspection by the destructive test was performed.

(Comparative Example 2)
The same operations as in Example 2 were performed until adjustment of the resin varnish, preparation of the prepreg, and preparation of the laminated plate. Thereafter, the inspection by the X-ray camera was omitted, and the bubble inspection by the destructive test was performed.

  The above evaluation results are shown in Table 1. Use of an X-ray camera reduces the number of bubbles in the laminate, and in particular for laminates containing barium sulfate as a contrast agent, the number of bubbles of 5 μm or more may be reduced, possibly providing a good quality laminate. I understood. In addition, it is considered that the quality of printed wiring boards and semiconductor devices using this laminated board is improved.

  By using the manufacturing method of the present invention, it is possible to supply a laminated board, a printed wiring board, a multilayer printed wiring board, and a semiconductor device in which bubbles (voids) contained in the laminated board are reduced. It is possible to supply an electronic material with stable performance and quality.

1 X-ray source 2 X-ray sensor 3 Sample (printed wiring board or laminated board)
4 Conveying device 5 Image processing device 6 Control device 7 Defect location marking device 8 X-ray

Claims (16)

A method for producing a laminated board in which a fiber base material is impregnated with a resin composition to prepare a prepreg, and then a metal foil is laminated on at least one surface of a laminated body in which at least one prepreg is laminated. And
It is confirmed by observation using an X-ray camera that bubbles larger than a predetermined size are not included, and when the presence of bubbles larger than the predetermined size is confirmed, this includes a step of making this a defective product A method for producing a laminated board.   The method for producing a laminated board according to claim 1, wherein the bubbles having a predetermined dimension or more are bubbles having a size of 30 µm or more.   The said resin composition contains resin and the contrast agent for X-rays, The manufacturing method of the laminated board of Claim 1 or 2 characterized by the above-mentioned.   The method for producing a laminated board according to claim 3, wherein the X-ray contrast medium contains barium sulfate particles.   The average particle diameter of the said barium sulfate is 3 micrometers or less, The manufacturing method of the laminated board of Claim 4 characterized by the above-mentioned.   The laminate according to any one of claims 3 to 5, wherein a content of the contrast agent for X-ray is 0.5% by mass or more and 70% by mass or less of the entire resin composition. A manufacturing method of a board.   The said resin contains an epoxy resin, The manufacturing method of the laminated board of any one of Claim 3 thru | or 6 characterized by the above-mentioned.   The method for producing a laminated board according to any one of claims 3 to 7, wherein the resin further contains a cyanate resin.   The method for producing a laminated board according to any one of claims 3 to 8, wherein the resin further contains a phenol resin.   The method for producing a laminated board according to any one of claims 1 to 9, wherein the resin composition further contains an inorganic filler.   The average particle diameter of the said inorganic filler is 0.3 micrometer or more and 5 micrometers or less, The manufacturing method of the laminated board of Claim 10 characterized by the above-mentioned.   The method for producing a laminated board according to claim 10 or 11, wherein the content of the inorganic filler is 20% by mass or more and 85% by mass or less of the entire resin composition.   A laminate produced by using the laminate production method according to any one of claims 1 to 12.   A multilayer or single-layer printed wiring board comprising the laminated board according to claim 13. A semiconductor device comprising a semiconductor element mounted on the printed wiring board according to claim 14. When a prepreg is produced by impregnating a fiber base material with a resin composition, an X-ray camera is used to obtain a laminate by laminating metal foil on at least one side of a laminate in which at least one prepreg is laminated. It is confirmed by the observation used that bubbles of a predetermined size or more are not included, and when the presence of bubbles of the predetermined size or more is confirmed, a resin used for manufacturing a laminate having this as a defective product and A resin composition comprising an X-ray contrast medium.