JP5310545B2 - Conductor paste composition for via hole filling, printed circuit board using the same, and method for producing the same - Google Patents

Description

  The present invention relates to a conductor paste composition for filling via holes, a double-sided printed board and a multilayer printed board using the same, and a method for producing them.

  In recent years, with increasing performance and miniaturization of electronic devices, circuit boards are required to have higher multilayers and higher density. It is known that high density can be achieved by inner via hole connection as a connection method between substrate layers that can connect ICs and components at the shortest distance. In the through-hole connection used for a general glass epoxy multilayer substrate, since the connection is made by plating the through-hole, it is difficult to connect only the necessary layers, and an electrode land is provided on the uppermost layer of the substrate. Because of the configuration, it is difficult to increase the mounting density due to these restrictions because the electrode land of the surface mounting component cannot be formed in that portion. In order to solve these problems, instead of through-holes, a hole that reduces the number of through-holes by opening up to half of the board is used, or the hole on the top layer of the board is closed by filling the through-hole with a conductive paste and then plating. A method for improving the density is performed, but the manufacturing process becomes complicated.

  On the other hand, in the inner via hole connection, it is possible to connect only necessary layers, and there is no through hole in the uppermost layer of the substrate, and the mountability is excellent. In an example in which this connection method is applied to a resin substrate (for example, a glass epoxy substrate), a double-sided substrate includes a substrate in which a low-viscosity solvent-type silver paste is embedded in a through hole using a printing method, dried, cured, and conductive. However, the connection resistivity is as high as about 10 mΩ · cm, and the reliability in thermal shock such as heat cycle is poor. In order to improve the embedding property of the conductive paste into the through-hole, as a means for reducing the viscosity of the paste, a method of using a small amount of conductive particles or adding a low boiling point solvent or a reactive diluent is performed. It was.

  However, reducing the additive amount of the conductor particles reduces the contact points between the fillers, increases the via hole connection resistivity, and cannot ensure reliability in a test in which thermal stress such as a heat cycle occurs. In addition, in the method of adding a low-boiling solvent or reactive diluent, the weight loss due to volatilization of these components is large during the curing of the hot press, and the volatile components cause swelling of the substrate, or wiring copper The adhesive strength with the foil is weakened. Therefore, by using linole dimer acid glycidyl ester epoxy resin as the main component while containing conductive particles at a high concentration, a low-viscosity, high-conductivity, heat-resistant shock conductive connection reliability conductor paste was realized without solvent. There is something.

  As prior art document information related to the invention of this application, for example, Patent Document 1 is known.

  However, in the above conventional example, linole dimer acid glycidyl ester epoxy resin is the main component, and the resin crosslink density is low, so it has low viscosity and is strong against thermal shock, but has high water absorption and high reliability in conductive connection in high humidity tests. Is lacking. In addition, since linole dimer acid glycidyl ester epoxy resin has low adhesion strength among epoxy resins, when a conductor paste using this as a main component is used for a via hole, the adhesive strength to wiring copper foil is not good. It is enough.

  In general, in order to reduce the water absorption rate of the epoxy resin and increase the adhesive strength, there is known a means of blending, for example, a bisphenol type epoxy resin having a low epoxy equivalent that can increase the crosslinking density. However, these low epoxy equivalent resins capable of reducing the water absorption rate and increasing the adhesive strength have higher viscosity than linole dimer acid glycidyl ester epoxy resins and the like. Therefore, the conductive paste cannot be filled with via holes.

  Moreover, if the abundance ratio of the conductive particles bearing conductivity in the inner via hole is large, the conductor resistance can be reduced. Therefore, it is effective to contain as many conductive particles as possible in the conductive paste. However, since it is a mixture of solid conductive particles and a liquid binder, there is a limit of the mixing ratio that can be made into a paste, and if the viscosity is too high, the filling property to the via is impaired. In particular, the smaller the diameter of the inner via hole, the more susceptible to the density of the conductive particles. Therefore, the continuity of the inner via hole is greatly affected.

  On the other hand, in order to reduce the conduction resistance in the via hole, the surface of the conductive particles contained in the conductor paste was reduced by containing chlorine in the conductor paste, but the chlorine content was excessive. If it becomes, the insulation of a printed circuit board will fall.

  In particular, when the chlorine content in the conductor paste is higher than the chlorine content in the prepreg, the chlorine contained in the conductor paste in the via hole penetrates into the prepreg. It tends to decrease.

Japanese Patent Laid-Open No. 7-176846

  The present invention is to produce a conductive paste composition that can provide electrical connection between electrode layers by small diameter inner via hole connection, high thermal shock resistance, high moisture resistance, and high connection strength. Moreover, a multilayer printed board is produced from the double-sided printed board including the inner via hole connection using this paste.

The conductor paste composition of the present invention is a conductor paste composition filled in a via hole, and (a) the average particle diameter is 0.5 to 20 μm and the specific surface area is 0.05 to 1.5 m. ² / g of conductive particles; 30-70% by volume; (b) one molecule having one or more epoxy groups, and the total amount of hydroxyl groups, amino groups and carboxyl groups is 5 mol% of the epoxy groups A resin containing 10% by weight or more of an epoxy compound having an epoxy equivalent of 100 to 350 g / eq; 70 to 30% by volume and 20 to 2000 ppm of chlorine.

  According to the double-sided printed board using the via hole filling conductor paste of the present invention, the method of forming the same, and the multilayer board using the same, a highly reliable small-diameter inner via hole is provided without using a through-hole plating technique. A double-sided printed circuit board can be realized, and its multilayering can be easily realized.

Sectional drawing which shows the double-sided printed circuit board in one embodiment of this invention Process drawing of formation method of double-sided printed circuit board in the embodiment Process drawing of formation method of double-sided printed circuit board in the embodiment Process drawing of formation method of double-sided printed circuit board in the embodiment Process drawing of formation method of double-sided printed circuit board in the embodiment Process drawing of the method of forming a multilayer printed circuit board in the same embodiment Process drawing of the method of forming a multilayer printed circuit board in the same embodiment Process drawing of another forming method of multilayer printed circuit board in the same embodiment Process drawing of another forming method of multilayer printed circuit board in the same embodiment Structure diagram of conductive particles used for printed circuit board in the same embodiment

(Embodiment 1)
Hereinafter, a double-sided printed board using the via hole filling conductor paste of the present invention, a method for forming the same, and a multilayer printed board using the same will be described in detail with reference to the drawings.

  FIG. 1 is a structural sectional view of an embodiment of a double-sided printed board according to the present invention. In FIG. 1, a double-sided printed circuit board 104 includes a laminated base material 101, a copper foil 102 (a copper foil of a wiring pattern), and a conductor via hole 103 having a small diameter of 150 μm or less filled with a conductor paste. The point of the present invention is that the conductive paste composition has a low viscosity and can be easily filled, and is a connection filled with a high content of conductive particles. In other words, it has a low resistivity and a low coefficient of thermal expansion, and the resin in the conductive paste composition has a low water absorption rate, a high adhesive strength, a solvent-free and a low volatility, and thus has high connection reliability in all environmental tests. An inner via hole substrate having a small diameter is produced. Note that the inner via hole connection is a method of connecting both surfaces and each layer of the multilayer printed board at an arbitrary position.

The conductor particles in the conductor paste composition that forms the conductor via hole 103 need to be contained in a high concentration in the conductor composition. The reason for this is that, as described above, it is necessary to maintain the connection reliability even when the resistivity of the connection via hole is lowered by increasing the contact probability between the conductive particles and the substrate distortion due to thermal or mechanical stress is applied. Because. In order to disperse the conductor particles at a high concentration, it is better that the average particle diameter of the conductor particles is in the range of 0.2 to 20 μm and the specific surface area is small, and the value is 0.05 to 1.5 m ² / g. Is appropriate. If the average particle size is less than 0.2 μm, the specific surface area exceeds 1.5 m ² / g and high concentration dispersion becomes impossible, and if it exceeds 20 μm, the conductor in the conductor paste filled in one via hole Connection reliability is reduced because the number of particles is too small. The specific surface area is not preferable average particle diameter is difficult to 20μm or less, 1.5 m 2 / high concentration of the dispersion of ^g by weight, the conductive particles becomes impossible for less than 0.05 m 2 / ^g . In addition, this conductor paste composition has a lower viscosity and a lower TI value in order to improve the filling property into the via hole, and an appropriate TI value is 1.0 or less. The TI value represents the relative ratio of the respective viscosities at different shear rates in a paste whose viscosity depends on the shear rate. In the present invention, the TI value is a ratio (A / B) of a viscosity (A) at a temperature: 25 ° C. and 1 [1 / sec] and a viscosity (B) at a temperature: 25 ° C. and 2 [1 / sec]. It is. In addition, the viscosity was measured using an E-type viscometer (DVU-E type) manufactured by Toki Sangyo Co., Ltd. at 25 ° C., R = 14 mm, 3 ° cone, 0.5 rpm (shear rate 1 (1 / s)) Measured under the conditions of

  In the present invention, the chlorine content needs to be lower than the chlorine content in the prepreg to ensure insulation, and 20 to 2000 ppm is appropriate. If it exceeds 2000 ppm, the insulating properties of the printed circuit board will decrease, and if it is less than 20 ppm, the connection resistance value of the via hole will increase, which is inappropriate.

  The case of exceeding 2000 ppm will be described in more detail. In this case, the chlorine content in the prepreg is higher than the chlorine content in the conductor paste filled in the via hole, and there is a risk that the chlorine concentration in the prepreg will increase, thereby increasing the insulating properties of the substrate. Decreases and migration tends to occur. In addition, when a semiconductor device is mounted on a land immediately above the via hole, chlorine in the via hole is easily transferred to the semiconductor device, and insulation with respect to the semiconductor device is reduced.

  In addition, as the kind of the conductor particles, most of the precious metals such as gold, platinum, silver and palladium or the base metals such as copper, nickel, tin, lead and indium can be used. You can also

  FIG. 5 is a structural diagram of conductive particles used for a printed circuit board in one embodiment of the present invention. In FIG. 5, the core 501 has a spherical shape, and the conductive material 502 covers the surface of the core 501 and serves as a conductive filler. In this way, not only pure metals but also alloys, metals, or insulating cores covered with a conductive material can be used. The shape of the conductor particles is not particularly limited as long as it has the above average particle diameter and specific surface area.

  In particular, the use of copper powder as the conductor particles is desirable from the viewpoints of migration suppression, economic supply, and price stability. However, since copper powder is generally easily oxidized, when used for filling via holes, the oxidation of copper powder hinders conductivity. Therefore, the oxygen concentration of the copper powder is preferably 1.0% by weight or less.

Next, the resin in the conductor paste 203 for forming the conductor via hole 103 will be described. In order to form a conductor composition for an inner via hole with high connection reliability, a resin having no solvent, low viscosity, low water absorption, and high adhesive strength is basically required. In order to obtain this physical property, the resin composition has one or more epoxy groups in one molecule, and the hydroxyl group, amino group, and carboxyl group are 5 mol% or less of the epoxy group, and the epoxy equivalent is 100 to 350 g. A resin containing 10 wt% or more of an epoxy compound which is / eq is used. The reason for using an epoxy compound as an essential component is to obtain high adhesive strength. In this epoxy compound, the reason why the hydroxyl group, amino group, and carboxyl group have a low concentration of 5 mol% or less of the epoxy group is that the conductive paste viscosity is low even if the resin viscosity is low if there is a functional group having a high hydrogen bonding force. This is because of the increase. On the contrary, if these functional groups having a high hydrogen bonding force have a low concentration of 5 mol% or less of the epoxy group, a conductor paste having a low viscosity can be obtained even if the resin viscosity is high. In addition, although the ratio of a hydroxyl group, an amino group, a carboxyl group, and an epoxy group can be confirmed by chemical quantitative analysis, the absorbance in the vicinity of 3500 cm ⁻¹ (due to the hydroxyl group, amino group, carboxyl group) and 910 cm in infrared spectroscopic analysis. ^It can also be confirmed by the ratio of absorbance in the vicinity of ⁻¹ (because of epoxy groups). In this epoxy compound, the reason why the epoxy equivalent is 100 to 350 g / eq is that when 350 g / eq or more, the crosslinking density is too low and the water absorption is high and the adhesive strength is low, and when it is less than 100 g / eq, the crosslinking density. This is because the curing shrinkage distortion becomes large and the adhesive strength is lowered. If the epoxy compound is contained in the resin in an amount of 10% by weight or more, a conductor paste composition having a low viscosity, a low water absorption rate and a high adhesive strength can be obtained. The resin component other than the epoxy compound is not particularly limited as long as it is solvent-free. Moreover, the epoxy hardening | curing agent for making an epoxy compound react and harden | cure as needed is also mix | blended. The conductor paste viscosity is desirably 2000 Pa · s or less, and the TI value is desirably 1 or less. If the viscosity is 2000 Pa · s or more and the TI value exceeds 1, there is a problem that the via hole filling operation cannot be performed. Also, the reason for making the resin solvent-free in the present invention is that, when a solvent is contained, when the conductive composition is heated and compressed after being filled into the via hole, the volatile component is volatilized and the via hole filled structure. This is because voids are generated inside or the prepreg is peeled off, resulting in unstable connection.

  As an epoxy compound suitable for use, a glycidyl ether type epoxy resin, a glycidyl ester type epoxy resin, a glycidyl amine type epoxy resin, an alicyclic epoxy resin, or the like is used. Among them, bisphenol glycidyl ether type epoxy resins, for example, bisphenol A type epoxy resin (Chemical formula 1), bisphenol F type epoxy resin (Chemical formula 2), bisphenol AD type (Chemical formula 3), hydrogenated bisphenol type epoxy resin (Chemical formula 4), By using an alkylene oxide-modified bisphenol-type epoxy resin (Chemical Formula 5), an alkoxy-modified bisphenol-type epoxy resin (Chemical Formula 6), etc., low viscosity, low water absorption and high adhesive strength can be obtained. These bisphenol glycidyl ether type epoxy resins are effective when used alone or in any combination.

  However, n ≧ 0.

  However, n ≧ 0.

  However, n ≧ 0.

  However, n ≧ 0.

  However, R = CpH2p + 1 (p ≧ 1) and m + n ≧ 2.

  However, R = CpH2p + 1 (p ≧ 1).

  The epoxy compound is selected from 90 to 20% by weight (group A) of bisphenol glycidyl ether type epoxy resin, C8 or more long chain aliphatic alcohol glycidyl ether type epoxy resin and C8 or more long chain fatty acid glycidyl ester type epoxy resin. The resin composed of at least one epoxy resin of 10 to 80% by weight (Group B) has a particularly low viscosity, a low water absorption and a high adhesive strength, and has a large relaxation effect against stress, so that the connection reliability of via holes is high. Increases nature.

  Here, examples of resins included in Group A include bisphenol A type epoxy resin (Chemical formula 1), bisphenol F type epoxy resin (Chemical formula 2), bisphenol AD type (Chemical formula 3), hydrogenated bisphenol type epoxy resin (Chemical formula 4). ), Alkylene oxide-modified bisphenol-type epoxy resin (Chemical Formula 5), alkoxy-modified bisphenol-type epoxy resin (Chemical Formula 6), and the like. Examples of resins included in Group B include linole dimer acid glycidyl ester type epoxy resin (Chemical Formula 7), isoprene caproic acid dimer glycidyl ester type epoxy resin (Chemical Formula 8), versatic acid glycidyl ester type epoxy resin (Chemical Formula 9). A lauryl glycidyl ether type epoxy resin (Chemical Formula 10) or the like can be used. These resins of Group A and Group B are effective when used alone or in any combination.

  However, R1, R2, and R3 are all alkyl groups, and the total number of carbon atoms is 8.

  In addition, epoxy compounds suitable for use include epoxy oligomers having an average molecular weight of 600 to 10,000. Epoxy oligomers have very small amounts of hydroxyl groups, amino groups, and carboxyl groups relative to the amount of epoxy groups, and when made into a conductive paste, the viscosity dependence on shear rate (TI value) decreases as the resin molecular weight increases. Therefore, it has the effect of obtaining a low-viscosity conductor paste. Furthermore, the epoxy oligomer also has an effect of improving the peel adhesive strength.

  The epoxy compound is bisphenol glycidyl ether type epoxy resin 90 to 19% by weight (group A), C8 or more long chain aliphatic alcohol glycidyl ether type epoxy resin and C8 or more long chain fatty acid glycidyl ester type epoxy resin 9 to 9%. Resins composed of 80% by weight (group B) and 1 to 30% by weight (group C) of epoxy oligomers having an average molecular weight of 600 to 10000 can have particularly low viscosity, low water absorption and high adhesive strength, and Since the stress relaxation effect is large, the connection reliability of the via hole is increased.

  Here, examples of resins included in Group A include bisphenol A type epoxy resin (Chemical formula 1), bisphenol F type epoxy resin (Chemical formula 2), bisphenol AD type (Chemical formula 3), hydrogenated bisphenol type epoxy resin (Chemical formula 4). ), Alkylene oxide-modified bisphenol-type epoxy resin (Chemical Formula 5), alkoxy-modified bisphenol-type epoxy resin (Chemical Formula 6), and the like. Examples of resins included in Group B include linole dimer acid glycidyl ester type epoxy resin (Chemical Formula 7), isoprene caproic acid dimer glycidyl ester type epoxy resin (Chemical Formula 8), versatic acid glycidyl ester type epoxy resin (Chemical Formula 9). A lauryl glycidyl ether type epoxy resin (Chemical Formula 10) or the like can be used. Furthermore, as examples of resins included in Group C, epoxidized unsaturated fatty acid modified products (Chemical Formula 11), epoxidized polybutadiene (Chemical Formula 12), epoxidized polystyrene butadiene copolymer (Chemical Formula 13), and the like can be used. . These resins of Group A, Group B, and Group C are effective when used alone or in any combination.

  However, R1 and R4 are all alkyl groups having 1 to 18 carbon atoms, R2 and R3 are both alkylene groups having 0 to 8 carbon atoms, and n ≧ 1.

  However, R and R ′ are all alkyl groups having 0 to 8 carbon atoms, and q ≧ 1, r ≧ 1, s ≧ 1, and t ≧ 1.

  However, R and R ′ are all alkyl groups having 0 to 8 carbon atoms, and v ≧ 1, w ≧ 1, x ≧ 1, y ≧ 1, and z ≧ 1.

  Moreover, you may add resin other than an epoxy compound to an electrically conductive paste as needed. Examples of resins suitable for use include imide resins and phenol resins for the purpose of improving heat resistance, and vinyl polymers such as polyolefin, acrylic resins, polyethers, and polyesters for the purpose of improving peel adhesion strength with copper foil. Polyamide, polyurethane and the like are used. These resins are effective when used alone or in any combination.

  Moreover, an epoxy hardening | curing agent may be mix | blended with the conductor paste as needed. As the epoxy curing agent, a curing agent generally used as a one-component composition can be used. For example, amine curing agents such as dicyandiamide and carboxyl hydrazide, imidazole curing agents such as heptadecylimidazole, urea curing agents such as 3- (3,4-dichlorophenyl) -1,1-dimethylurea, and methylhexaphthalic anhydride An acid anhydride curing agent such as methyl nadic anhydride, a phosphine curing agent such as triphenylphosphine, and a Lewis acid such as hexafluoroantimony salt are used. Among these, a latent curing agent is particularly desirable from the viewpoint of the stability and workability of the composition. Here, the latent curing agent is a reaction that is stopped at room temperature and can be stored for a long time without changing its characteristics, and when heated above a predetermined temperature, the particles melt, decompose or dissolve and are contained. The active group appears, the reaction is started all at once, and it has a function of curing quickly.

  Moreover, a dispersing agent may be mix | blended with the conductor paste as needed. As the dispersant, commonly used dispersants can be used. First, non-ionics such as higher fatty acid ethylene oxide, propylene oxide addition ester, sorbitan and fatty acid ester compound, polyhydric alcohol ethylene oxide such as sorbitan, propylene oxide addition ether compound, alkylbenzene ethylene oxide, propylene oxide addition product, etc. Anionic dispersants such as alkylbenzene sulfonic acid alkali salts, higher alcohol sulfate ester alkali salts, phosphate ester compounds, higher fatty acids, higher fatty acid ethylene oxides, and propylene oxide adduct sulfate alkaline salts Third, a quaternary ammonium salt type cationic dispersant is typically used. The dispersant referred to here has an effect of promoting lowering of the viscosity and lowering of the TI value of the paste by increasing the affinity between the surface of the metal particles and the organic resin blended as the binder in the paste.

  As the laminated base material 101, there is no limitation as long as the thickness becomes thinner after curing than the prepreg at the time of pressing, and most known laminated base materials can be used. For example, any one of glass woven fabric, glass nonwoven fabric, aramid woven fabric, aramid nonwoven fabric and a thermosetting resin such as epoxy resin, or glass woven fabric, glass nonwoven fabric, aramid woven fabric, aramid nonwoven fabric Insulating material using a composite material or film material of one and a thermoplastic resin having a glass transition temperature of 180 ° C. or higher (for example, wholly aromatic polyester resin, polyether sulfone, polyether ketone, polyether ether ketone, etc.) Can be formed.

  2A to 2D are process diagrams of the method for forming a double-sided substrate of the present invention. In FIG. 2A, the laminated substrate 201 is a prepreg. A through hole having a hole diameter of 150 μm or less is opened in the prepreg. In general, a drill is often used, but other processing methods such as a laser beam can be used depending on the material. Then, the conductive paste 203 is filled in the through holes. FIG. 2B shows a state where FIG. 2A is sandwiched between copper foils 202. FIG. 2C shows a state after applying heat and pressure to FIG. 2B. FIG. 2C shows a state in which the metal filling amount is increased after heating and pressurizing the through hole opened in the prepreg. The prepreg is compressed to reduce the thickness, and the resin is cured. The conductor paste 203 is in a compressed state. The conductor paste in a compressed state is a conductor via hole 103. The conductor via hole 103 plays a role of electrical connection between the upper and lower surfaces. FIG. 2D shows a state after the surface copper foil 202 is processed (etching or the like) to form a wiring pattern. The processed copper foil 102 becomes a circuit conductor. A printed circuit board that is put to practical use has processes such as applying a solder resist, printing characters and symbols, and making holes for insertion parts, but this is not essential here and is omitted.

  3A and 3B show a process of making a multilayer printed circuit board by repeatedly using the double-sided printed circuit board formation method described above. FIG. 3A shows a state in which the through-hole shown in FIG. 2A is filled with a conductive paste on both sides (upper and lower surfaces) of the double-sided printed circuit board 104 to be a core, and a copper foil 202 is further placed. In this state, if heat and pressure are applied from the upper and lower surfaces, the multilayer printed board of FIG. 3B is produced, and the inner via hole connection has already been completed. Furthermore, if the upper and lower copper foils 202 are processed into a pattern, a four-layer multilayer printed board is completed. Thereafter, this process can be repeated to produce a multilayer printed board having a larger number of layers.

  3A and 3B, the double-sided printed circuit board according to the present invention is used as the double-sided printed circuit board of the core, but this is not always necessary, and a conventional through-hole double-sided printed circuit board can be used. Therefore, it is not necessary to prepare equipment for newly creating a double-sided printed circuit board, and the cost can be reduced. In this case, it is better to fill the through hole (through hole) in advance. Here, the through-hole substrate refers to a resin substrate. As the through-hole substrate, not only a resin substrate but also a ceramic substrate can be used.

  4A and 4B show another method for forming a multilayer printed board. In FIG. 4A, the laminated base material 201 before heating and pressing filled with the conductive paste 203 is sandwiched between two double-sided printed boards 104. In this state, heating and pressurization can be performed to obtain the four-layer multilayer printed board shown in FIG. 4B. If not only four layers but also a plurality of double-sided printed boards are prepared, and the laminated base material before heating and pressurizing filled with the conductive particles is sandwiched between the double-sided printed boards and heated and pressed, more multilayers can be obtained. A multilayer printed circuit board can be produced.

  4A and 4B, the double-sided printed board of the present invention is used as the double-sided printed board. However, this is not always necessary, and a conventional through-hole double-sided printed board can be used. As the through-hole substrate, not only a resin substrate but also a ceramic substrate can be used.

  Next, the characteristic of the printed wiring board with respect to the chlorine content of the conductor paste composition of the present invention will be described using a table.

  Table 1 shows the connection resistance value and the insulation resistance value of the via hole with respect to the amount of hydrolyzable chlorine contained in the paste and the diameter of the via hole.

  As shown in Table 1, if the amount of hydrolyzable chlorine in the conductor paste composition filled in the via hole of the printed wiring board in the present invention is 20 ppm or more, the connection resistance value is even if the via hole diameter is 150 μm or less. The result was 10 mΩ / via or less, and good electrical conductivity was obtained.

  In addition, when the hydrolyzable chlorine content of the conductor paste composition was lower than the chlorine content in the prepreg, that is, 2000 ppm or less, good results were obtained also in the insulation resistance value.

  And any one of glass woven fabric, glass nonwoven fabric, aramid woven fabric, aramid nonwoven fabric and a thermosetting resin such as epoxy resin, or glass woven fabric, glass nonwoven fabric, aramid woven fabric, aramid nonwoven fabric Insulating material using a composite material or film material of one and a thermoplastic resin having a glass transition temperature of 180 ° C. or higher (for example, wholly aromatic polyester resin, polyether sulfone, polyether ketone, polyether ether ketone, etc.) Can be formed.

As described above, according to the first embodiment, the conductor paste composition of the present invention has (a) an average particle diameter of 0.5 to 20 μm and a specific surface area of 0.05 to 1.5 m ^2. / G conductive particles; 30-70% by volume; (b) one or more epoxy groups in one molecule, and the total amount of hydroxyl groups, amino groups and carboxyl groups is 5 mol% or less of the epoxy groups A resin containing 10 wt% or more of an epoxy compound having an epoxy equivalent of 100 to 350 g / eq; 70 to 30 vol%, and 20 to 2000 ppm of chlorine. By filling a via hole of 150 μm or less, a double-sided or multilayer printed circuit board having a highly reliable inner via hole can be realized.

  In the first embodiment of the present invention, the hole diameter of the via hole is set to 150 μm or less, but the hole diameter may be larger than 150 μm.

  The conductor paste composition of the present invention is necessary for high-frequency circuit applications capable of high-speed transmission as a high-density wiring substrate, fine wiring pattern applications such as semiconductor packages, and portable electronic device applications that require miniaturization and weight reduction. It is useful for forming an inexpensive printed wiring board having high connection reliability.

101, 201 Laminated substrate 102, 202 Copper foil 103 Conductor via hole 104 Double-sided printed board 203 Conductor paste 501 Core 502 Conductive material

Claims (11)

By filling the conductive paste composition in the via hole opened in the insulating base material, the upper and lower electrode layers on the surface of the insulating base material are electrically connected, and an electrode for mounting a semiconductor device is directly above the via hole. A conductor paste composition for filling via holes used in a printed circuit board having:
Conductor particles containing at least copper powder having an average particle size of 0.5 to 20 μm and a specific surface area of 0.05 to 1.5 m ² / g;
10 weight of an epoxy compound having one or more epoxy groups in one molecule, the total amount of hydroxyl group, amino group and carboxyl group is 5 mol% or less of the epoxy group, and the epoxy equivalent is 100 to 350 g / eq Resin containing 70% or more; and 70 to 30% by volume,
A conductor paste composition for filling via holes, wherein the content of hydrolyzable chlorine is 20 to 2000 ppm. The conductor particles are
(1) at least one particle selected from gold, platinum, silver, palladium, copper, nickel, tin, lead, and indium;
(2) Alloy particles of any combination selected from gold, platinum, silver, palladium, copper, nickel, tin, lead, indium, zinc, chromium,
(3) Particles coated with at least one metal selected from gold, platinum, silver, palladium, copper, nickel, tin, lead, and indium with conductive or non-conductive particles as nuclei, and
(4) Particles coated with an alloy of any combination selected from gold, platinum, silver, palladium, copper, nickel, tin, lead, indium, zinc, and chromium, with conductive or non-conductive particles as the core ( 2. The via-hole filling conductor paste composition according to claim 1, which is at least one particle selected from 1) to (4). The conductor paste composition for via hole filling according to claim 1, wherein the conductor particles contain copper having a surface oxygen concentration of 1.0% by weight or less. By filling the conductive paste composition in the via hole opened in the insulating base material, the upper and lower electrode layers on the surface of the insulating base material are electrically connected, and an electrode for mounting a semiconductor device is directly above the via hole. A conductor paste composition for filling via holes used in a printed circuit board having:
Conductor particles containing at least copper powder having an average particle size of 0.5 to 20 μm and a specific surface area of 0.05 to 1.5 m ² / g;
10 weight of an epoxy compound having one or more epoxy groups in one molecule, the total amount of hydroxyl group, amino group and carboxyl group is 5 mol% or less of the epoxy group, and the epoxy equivalent is 100 to 350 g / eq Resin containing 70% or more; and 70 to 30% by volume,
The epoxy compound, Ri least one epoxy resin der selected from glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resins and alicyclic epoxy resins,
A conductive paste composition for filling via holes , wherein the content of hydrolyzable chlorine is 500 to 2000 ppm. The conductor paste composition for via hole filling according to claim 4 , wherein the epoxy compound is a bisphenol glycidyl ether type epoxy resin. The conductor paste composition for via-hole filling according to claim 4 , wherein the epoxy compound contains an epoxy oligomer having a weight average molecular weight of 600 to 10,000. The epoxy compound is
90-20% by weight of a bisphenol glycidyl ether type epoxy resin,
C8 or more to claim 4 is a resin composed of at least 10 to 80 wt% one epoxy resin selected from a long chain aliphatic alcohol glycidyl ether type epoxy resin and C8 or more long chain fatty acid glycidyl ester type epoxy resin The conductor paste composition for filling via holes as described. The epoxy compound is
Bisphenol glycidyl ether type epoxy resin; 90 to 19% by weight;
At least one resin selected from a long-chain aliphatic alcohol glycidyl ether type epoxy resin having 8 or more carbon atoms (C) and a long-chain fatty acid glycidyl ester type epoxy resin having 8 or more carbon atoms; 9 to 80% by weight;
The conductive paste composition for filling via holes according to claim 4 , which is a resin composed of an epoxy oligomer having a weight average molecular weight of 600 to 10000; 1 to 30% by weight. In the viscosity characteristics of the paste composition,
The via hole filling according to claim 4 , wherein the ratio (A / B) of the temperature (25 ° C), the viscosity (A) at 1 [1 / sec] and the viscosity (B) at 2 [1 / sec] is 1 or less. Conductor paste composition. By filling the conductive paste composition in the via hole opened in the insulating base material, the upper and lower electrode layers on the surface of the insulating base material are electrically connected, and an electrode for mounting a semiconductor device is directly above the via hole. a printed circuit board that Yusuke,
The conductor paste composition is
Conductor particles containing at least copper powder having an average particle size of 0.5 to 20 μm and a specific surface area of 0.05 to 1.5 m ² / g;
10 epoxy compounds having one or more epoxy groups in one molecule, the total amount of hydroxyl groups, amino groups and carboxyl groups being 5 mol% or less of the epoxy groups and an epoxy equivalent of 100 to 350 g / eq. Resin containing not less than 70% by weight; 70 to 30% by volume;
Hydrolyzable chlorine having a content of 20 to 2000 ppm and lower than the content in the insulating substrate,
The printed circuit board, wherein the conductor paste composition is cured in the via hole. By filling the conductive paste composition in the via hole opened in the insulating base material, the upper and lower electrode layers on the surface of the insulating base material are electrically connected, and an electrode for mounting a semiconductor device is directly above the via hole. A printed circuit board manufacturing method comprising:
Forming a via hole in advance in a prepreg used for manufacturing a printed circuit board;
In the via hole,
30-70% by volume of conductive particles containing at least copper powder having an average particle size of 0.5-20 μm and a specific surface area of 0.05-1.5 m ² / g;
10 epoxy compounds having one or more epoxy groups in one molecule, the total amount of hydroxyl groups, amino groups and carboxyl groups being 5 mol% or less of the epoxy groups and an epoxy equivalent of 100 to 350 g / eq. 70 to 30% by volume of a resin containing at least wt%,
Filling a conductive paste composition comprising 20-2000 ppm and hydrolyzable chlorine lower than the content in the prepreg;
Placing and heating and pressing copper foil on the upper and lower layers of the prepreg; and
Forming an electrical circuit by etching the copper foil;
A method of manufacturing a printed circuit board comprising:

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