JP4834997B2 - Photosensitive dielectric paste and method for manufacturing electronic circuit component using the same - Google Patents

Description

  The present invention relates to a photosensitive paste capable of forming a dielectric layer having a high dielectric constant and fine through holes at a low temperature. The photosensitive paste of the present invention is used for ceramic capacitors and the like.

  Conventionally, ceramic multilayer wiring boards have been widely used as electronic parts for electronic devices, but with the rapid spread of portable electronic devices such as mobile phones and notebook computers in recent years, ceramic multilayer wiring boards, etc. There is a demand for miniaturization of electronic components.

  However, since the ceramic multilayer wiring board is configured by individually mounting the ceramic wiring board, the capacitor element, and the resistance element on the external circuit board, it is difficult to reduce the size. Therefore, a ceramic multilayer wiring board with a built-in capacitor in which a ceramic layer with a high dielectric constant is interposed inside the ceramic multilayer wiring board and a capacitor is built in has been proposed.

  As a method of incorporating this capacitor, a green sheet lamination method and a thick film printing method are known. The green sheet laminating method is one in which dielectric green sheets and insulating green sheets are alternately laminated, which is advantageous for multilayering. In the thick film printing method, a conductor is formed with a conductive paste on an insulating green sheet, a conductor is embedded in a via hole, a dielectric paste is printed on a capacitor forming portion, and a counter electrode is printed thereon. Further, it is a method in which the conductive paste and the dielectric paste are repeatedly printed to be multilayered and then fired. In either case, it is necessary to form a via hole in order to make an interlayer connection between dielectric layers. Conventionally, via holes have been formed by screen-printing a dielectric paste. However, in thick film screen printing, printing of holes of 100 μm or less is difficult in mass production, and about 150 μm is said to be the minimum. Therefore, a method for forming a fine via hole by adding a photosensitive organic component to the dielectric paste and using a photolithography technique (photosensitive paste method) has been proposed (for example, Patent Document 1).

  However, in the photosensitive dielectric paste disclosed in Patent Document 1, a perovskite complex oxide such as barium titanate is exemplified as the dielectric powder. However, these firing temperatures are substantially 1300 to 300. 1350 ° C. is necessary, and firing at a low temperature of about 800 to 900 ° C. has a problem that the denseness is poor and the desired physical properties cannot be obtained. Further, when firing at a high temperature around 1300 ° C., there is a problem that inexpensive silver or copper having a low melting point cannot be used for the electrode, and the production cost is increased.

Moreover, in patent document 2, although the dielectric composition which consists of a mixture of 90-99 mass parts barium titanate and 1-10 mass parts of glass is illustrated as a dielectric composition baked at 900-1000 degreeC. At a firing temperature of 800 to 850 ° C., the denseness was insufficient and the desired physical properties were not obtained.
Japanese Patent Laid-Open No. 06-251621 (pages 2 to 10) JP 2004-203626 A (pages 1 to 10)

  SUMMARY OF THE INVENTION In view of the above prior art, an object of the present invention is to provide a photosensitive dielectric paste that can form a dielectric layer having a high dielectric constant and fine through holes at a low temperature.

That is, the present invention is a paste comprising an inorganic powder and a photosensitive organic component, wherein the inorganic powder is a dielectric powder (A) having a relative dielectric constant of 100 or more, a relative dielectric constant of 50 or less, and a softening point of 500. in a range of ~900 ℃, _SiO 2 1~70 wt% in terms of oxide title
Al ₂ O ₃ 3~50 wt%
B ₂ O ₃ 4 to 20 wt%
MgO 1-20% by mass
Wherein and _{CaO, BaO, TiO 2, PbO} , Bi 2 O 3, Li 2 O, the glass powder (B) to at least one compound of _{K 2} O and Na ₂ O containing 0.1 to 10 mass%, The dielectric powder (A) and the glass powder (B) have a mass ratio in the range of 55:45 to 85:15 , and the dielectric powder (A) is barium titanate, calcium titanate, titanium A photosensitive dielectric paste comprising at least one dielectric powder selected from the group of strontium acid and calcium zirconate . Moreover, it is a manufacturing method of the electronic circuit component manufactured from the said photosensitive dielectric paste.

  According to the present invention, it is possible to provide a photosensitive dielectric paste that can form a dielectric layer having a high dielectric constant and fine through holes at a low temperature.

The photosensitive dielectric paste in the present invention comprises at least a dielectric powder having a relative dielectric constant of 100 or more, a glass powder having a relative dielectric constant of 50 or less, and a softening point in the range of 600 to 900 ° C. and a photosensitive organic component. Including.

Examples of the dielectric powder having a relative dielectric constant of 100 or more include powders based on lead, powders based on barium titanate, and titanium oxide. Except for titanium oxide, most of them are ABO ₃ called a perovskite structure. It consists of a mold and has the characteristic that the composition can be controlled to a constant stoichiometric ratio.

Examples of the powder based on lead include lead titanate, lead tungstate, lead nitrite, lead ferrate, lead magnesiumate, lead niobate, lead nickelate, lead zirconate and the like. _{Specifically, (Fe x W (1-} x)) O 3 -Pb (Fe y Nb (1-y)) O 3, PbTiO 3 -Pb (Mg x Nb (1-x)) O 3, Pb _{(Zn x Nb (1-x} )) O 3 -BaTiO 3, Pb (Zn x Nb (1-x)) O 3 -Pb (Fe y W (1-y)) O 3 -Pb (Fe z Nb ( _1-z) ) O ₃ , Pb (Zn _x Nb _(1-x) ) O ₃ —PbTiO ₃ —BaTiO ₃ , Pb (Mg _x W _(1-x) ) O ₃ —PbTiO ₃ —BaTiO ₃ , Pb ( _{mg x Nb (1-x)} ) O 3 -PbTiO 3 -Pb (mg y W (1-y)) O 3, Pb (mg x W (1-x)) O 3 -Pb (Zr y TiO (1 _{-y)) O 3 + ZnO,} Pb (Mg x Nb (1-x)) O 3 -PbTiO 3 -Pb _{O, Pb (Fe x Nb (} 1-x)) O 3 -Pb (Mg y Nb (1-y)) O 3, 2 -way system, such as _{(1-z) PbTiO 3 -Z} (La 2 O 3) or or complex perovskite compound of the _{ternary, (Pb x Ba (1-} x)) ZrO 3, Sr x Pb (1-x) TiO 3, PLZT (Pb (1-x) La x) (Zr y Ti z ) _{(1-x / 4)} O ₃ ) and the like.

Examples of the powder based on barium titanate include barium titanate, strontium titanate, calcium zirconate, and calcium titanate. _{Specifically, (Ba x Sr (1-} x)) (Sn y Ti (1-y)) O 3, Ba, (Ti x Sn (1-x)) O 3, Ba x Sr (1-x ₎ Binary systems such as TiO ₃ , BaTiO ₃ —CaZrO ₃ , BaTiO ₃ —Bi ₄ Ti ₃ O ₁₂ , (Ba _x Ca _(1-x) ) (Zr _y TiO _(1-y) ) O ₃ or 3 Examples of the compound include ternary compounds, preferably at least one dielectric compound selected from the group consisting of barium titanate, calcium titanate, strontium titanate and calcium zirconate.

Further, a perovskite complex oxide containing at least Pb, Mg, Nb and Ti as the metal element is preferable because the firing temperature can be lowered. Specifically, when the composition based on the molar ratio of the metal element oxide is expressed as xPb (Mg _1/3 Nb _2/3 ) O ₃ —yPbTiO ₃ , x and y are 91 ≦ x ≦ 99, 1 ≦ y. ≦ 9, x + y = 100 is satisfied. When x and y are within this range, a high dielectric constant and a high insulation resistance can be obtained.
In particular, in the present invention, it is preferable to use a dielectric powder having a relative dielectric constant of 800 or more because a high dielectric constant is exhibited when a photosensitive dielectric paste is formed as a dielectric layer. More preferably, a dielectric having a relative dielectric constant of 1000 or more is used.
Furthermore, at least one dielectric powder selected from the group consisting of barium titanate, calcium titanate, strontium titanate and calcium zirconate is obtained from the viewpoint of obtaining a dielectric powder having a relative dielectric constant of 800 or more and high insulation resistance. It can be preferably used.

The glass powder (B) used for the photosensitive dielectric paste of the present invention must have a relative dielectric constant of 50 or less and a softening point in the range of 500 to 900 ° C. In particular, when the softening point is in the range of 500 to 900 ° C., the denseness of the dielectric layer can be improved, a high insulation resistance can be obtained, and the photosensitive dielectric paste can be fired at a low temperature. A preferable softening point range is 600 to 850 ° C.
Furthermore, you may contain the glass powder (C) whose softening point is 350-480 degreeC. By containing glass powder having a softening point of 350 to 480 ° C., the denseness can be further improved and the hygroscopicity of the dielectric layer can be significantly improved. Preferably, the mass ratio of the glass powder (C) having a softening point of 350 to 480 ° C. and the glass powder (B) having a softening point of 500 to 900 ° C. is in the range of 2:98 to 35:65. More preferably, it is in the range of 2:98 to 20:80.

  The glass powder having a softening point of 350 to 550 ° C. contains 20 to 90 parts by mass of at least one of bismuth oxide, lead oxide, and zinc oxide. It is preferable in terms of easy point. When the content of these components exceeds 90 parts by mass, the heat-resistant temperature of the glass is lowered, which is not preferable in terms of baking onto a glass substrate, and when the content is less than 20 parts by mass, the baking temperature and softening point are not satisfied. It is less effective to control.

  It is also effective to contain silicon oxide, boron oxide, zirconium oxide, etc. as other components.

  Silicon oxide is preferably blended within a range of 5 to 40 parts by mass. When the amount is less than 5 parts by mass, the denseness, strength and stability of the glass layer are lowered, the thermal expansion coefficient is out of the preferred range, and a mismatch between the glass substrate and the thermal expansion coefficient may occur. When it exceeds 40 parts by mass, the softening point and the glass transition point increase, and the heat resistant temperature increases. Air bubbles remain and the electric insulation tends to be lowered.

  Boron oxide is preferably blended within the range of 5 to 30 parts by mass. By blending within this range, electrical, mechanical and thermal characteristics such as electrical insulation, strength, thermal expansion coefficient, and denseness can be improved. If it exceeds 30 parts by mass, the stability of the glass tends to decrease.

  Zirconium oxide is preferably blended within a range of 3 to 10 parts by mass. Since the acid resistance of the glass layer can be improved by blending zirconium oxide, the storage stability of the glass paste can be improved. If it is less than 3 parts by mass, the effect of improving storage stability is small, and if it exceeds 10 parts by mass, the heat resistance temperature of the glass layer becomes high, and baking onto a glass substrate becomes difficult.

  Moreover, when containing 20-90 mass parts of bismuth oxide and lead oxide, you may mix | blend zinc oxide within the range of 2-20 mass parts. By blending within this range, denseness and insulation resistance are improved.

  In addition to the above, phosphorus oxide, lithium oxide, potassium oxide, sodium oxide, barium oxide, aluminum oxide, magnesium oxide and the like can be blended as necessary.

The softening point of 500 to 900 ° C. of glass powder (B), specifically, _SiO 2 1 to 70% by mass in oxides terms notation
Al ₂ O ₃ 3~50 wt%
B ₂ O ₃ 4 to 20 wt%
MgO 1-20 % by mass
And _{CaO, BaO, TiO 2, PbO} , Bi 2 O 3, Li 2 O, is preferably at least one compound of _{K 2} O and Na ₂ O is a glass containing 0.1 to 10 mass%.

  The component containing the oxide within the above range and the mass ratio thereof can be adjusted as appropriate according to the values according to the characteristics required of the dielectric layer.

In the case of using such a dielectric powder and glass powder as a photosensitive paste, the particle size and particle size distribution become important. It is important that the photosensitive paste has sufficient light to be transmitted to the bottom of the film during exposure. By transmitting light during exposure to the bottom of the film, a uniform via hole with no difference in the upper and lower hole diameters can be obtained. The preferable particle diameter capable of obtaining such characteristics is that the central particle diameter (D ₅₀ ) is in the range of 0.1 to 3 μm and the maximum particle diameter is 8 μm or less. More preferably, the center particle diameter (D ₅₀ ) is in the range of 0.5 to 2.5, and the maximum particle diameter is 5 μm or less. In particular, when the maximum particle diameter exceeds 8 μm, problems such as a decrease in the reliability of the dielectric layer may occur when the number of layers is increased. The central particle size (DD ₅₀ ) and the maximum particle size can be obtained from a volume reference distribution such as a Coulter counter method, a photon correlation method, and a laser diffraction method.

  In the present invention, the mass ratio between the dielectric powder (A) and the glass powder (B) is important. When the mass ratio of A and B is in the range of 55:45 to 85:15, the dielectric layer retains its denseness even when fired at a low temperature of about 800 to 900 ° C., and exhibits a high dielectric constant. A body layer can be formed. Preferably, the mass ratio of A and B is in the range of 60:40 to 80:20, more preferably in the range of 65:35 to 75:25. Moreover, since it can be fired at a low temperature, inexpensive silver or copper having a low melting point can be used for the electrode, and electronic circuit components such as a capacitor built-in ceramic multilayer wiring board can be manufactured at a low cost.

  The denseness of the dielectric layer can be evaluated by measuring the water absorption rate of the dielectric layer. As the water absorption increases, the denseness becomes poor. A preferable water absorption is 0.5% or less. More preferably, it is 0.2% or less. A moisture content meter can be used for measuring the water absorption rate. In the present invention, a trace moisture content measuring device AQ-7 and a moisture vaporization accessory device EV-6 manufactured by Hiranuma Sangyo Co., Ltd. are used and heated at 200 ° C. Measurement was performed by a vaporization method (a method in which a sample was heated at 200 ° C. to vaporize water, and this was guided to a hand-defined cell with dry nitrogen gas).

  In addition, the photosensitive paste of the present invention may contain inorganic powder other than the above-described dielectric powder and glass powder. For example, an inorganic pigment may be included for identifying the insulating layer when multilayered. In the case of black, it is made of a compound such as Co—Cr—Fe, Co—Mn—Fe, Co—Cu—Mn, Co—Ni—Mn, Co—Ni—Cr—Mn, and Co—Ni—Cu—Mn. Black pigment, in the case of blue, Co-Al, Co-Al-Cr, Co-Al-Si, Zr-Si-V, Co-Zn-Si, Co-Zn-Al, Co-Zr-V, Co- For Si, green, Ca-Si-Cr, Sn-Zr-V, Zr-Si-Pr-V, Zr-Si-Pr-Cr-Fe, Cr-Al, Zr-Si-Pr-Cr, Cr In the case of -Co-Al-Zn, Cr-Al-Si, and vermilion, pigments such as Al-Mn, Al-Cr-Zn, Sn-Cr, and Zr-Si-Fe can be used. The addition amount of the pigment is usually in the range of 0.1 to 10 parts by mass although it depends on the kind of the pigment.

  The photosensitive organic component in the present invention is a photosensitive organic component (portion obtained by removing inorganic components from the paste) in the photosensitive paste, and is preferably contained in an amount of 5 to 50 parts by mass in the paste.

  Photosensitive organic components include polymers, monomers, photopolymerization initiators, organic solvents with photoacid generators, photobase generators, sensitizers, sensitizers, ultraviolet absorbers, organic dyes, dispersants, plasticizers. And additive components such as thickeners, acids, bases, anti-settling agents, and polymerization inhibitors.

  The polymer used as the organic component of the present invention preferably has a hydroxyl group or a carboxyl group.

  Examples of the polymer having a hydroxyl group include a copolymer obtained by polymerizing another monomer copolymerizable with a monomer having a hydroxyl group as a main copolymerizable monomer. As the monomer having a hydroxyl group, hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, Examples include 4-hydroxybutyl (meth) acrylate, glycerol (meth) acrylate, dipentaerytriol mono (meth) acrylate, and the like. Examples of monomers copolymerizable with these monomers having a hydroxyl group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, and isobutyl. Examples include (meth) acrylate, sec-butyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, stearyl (meth) acrylate, and the like.

  An acrylic resin containing a carboxyl group can be obtained by copolymerizing the monomer and an unsaturated acid such as an unsaturated carboxylic acid. Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, vinyl acetic acid, and acid anhydrides thereof. The acid value of the obtained resin having a carboxyl group is preferably in the range of 50 to 180, more preferably 70 to 140.

  In order to improve the curing rate, it is preferable that at least a part of the polymer has a carbon-carbon double bond in a side chain or a molecular end. Examples of the group having a carbon-carbon double bond include a vinyl group, an allyl group, an acrylic group, and a methacryl group. In order to add such a functional group to a polymer, a compound having a glycidyl group or an isocyanate group and a carbon-carbon double bond with respect to a mercapto group, amino group, hydroxyl group or carboxyl group in the polymer, or acrylic acid chloride There is a method of making an addition reaction of methacrylic acid chloride or allyl chloride.

  Examples of the compound having a glycidyl group and a carbon-carbon double bond include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, glycidyl ethyl acrylate, crotonyl glycidyl ether, glycidyl crotonate, and glycidyl isocrotonate. Examples of the compound having an isocyanate group and a carbon-carbon double bond include acryloyl isocyanate, methacryloyl isocyanate, acryloylethyl isocyanate, and methacryloylethyl isocyanate.

  As the monomer, a compound having an active carbon-carbon unsaturated double bond can be used. As the functional group, monofunctional and polyfunctional compounds having a vinyl group, an allyl group, an acrylate group, a methacrylate group, or an acrylamide group can be applied. Specific examples include allylated cyclohexyl diacrylate, 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate. , Dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylolpropane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol diacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol di Acrylate, trimethylolpropane tri Examples thereof include acrylate, diacrylate of bisphenol A diacrylate, diacrylate of bisphenol A-ethylene oxide adduct, diacrylate of bisphenol A-propylene oxide adduct, or a compound in which the acrylic group of the above compound is partially or entirely replaced with a methacryl group. .

  The monomer in the present invention preferably contains a polymerizable polyfunctional monomer having a molecular weight in the range of 100 to 5000 and having two or more polymerizable unsaturated groups from the viewpoint that the sensitivity of the photosensitive dielectric paste can be improved. . Furthermore, it contains a monofunctional alkane (meth) acrylate having a carbon number in the range of 10 to 20 from the point that the development margin can be expanded because the resistance to the developing solution can be obtained and the adhesion to the base can be improved. More preferred. When the number of carbon atoms is less than 10, the effect of expanding the development margin and improving the adhesion to the substrate is poor, and when the number of carbon atoms exceeds 20, the compatibility of the photosensitive dielectric paste tends to be poor. The monomer in the present invention is composed of a polymerizable polyfunctional monomer having a molecular weight in the range of 100 to 5000, a polymerizable unsaturated group having 3 or more, and a monofunctional alkane having a carbon number in the range of 10 to 20 (meta It is more preferable to use a mixture of acrylates.

  The photopolymerization initiator used in the present invention is selected from those generating radical species. As photopolymerization initiators, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane- 1-one, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl-phenylketone, 1-phenyl-1,2-propanedione-2- (o-ethoxy) Carbonyl) oxime, 2-methyl- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1, Benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl Ether, benzoin isobutyl ether, benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4,4-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, alkylated benzophenone, 3,3 ' , 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] benzenemethananium bromide, (4-Benzoylbenzyl) trimethylammonium chloride, 2-hydroxy-3- (4-benzoylphenoxy) -N, N, N-trimethyl-1-propenaminium chloride monohydrate, 2-isopropylthioxanthone, 2,4- Dimethyl Oxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 2-hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy) -N, N, N-trimethyl- 1-propanaminium chloride, 2,4,6-trimethylbenzoylphenylphosphine oxide, 2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2-bi Imidazole, 10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methylphenylglyoxyester, η5-cyclopentadienyl-η6-cumenyl-iron (1 +)-hexafluorophosphate (1-), diphenyl sulfide derivative, bis ( η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium, 4,4-bis (dimethylamino) benzophenone, 4 , 4-bis (diethylamino) benzophenone, thioxanthone, 2-methylthioxanthone, 2-chlorothioxanthone, 4-benzoyl-4-methylphenylketone, dibenzylketone, fluorenone, 2,3-diethoxyacetophenone, 2,2-dimethoxy 2-phenyl-2-phenylacetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyldichloroacetophenone, benzylmethoxyethyl acetal, anthraquinone, 2-t-butylanthraquinone, 2-aminoanthraquinone, β- Chloranthraquino , Anthrone, benzanthrone, dibenzsuberone, methyleneanthrone, 4-azidobenzalacetophenone, 2,6-bis (p-azidobenzylidene) cyclohexane, 2,6-bis (p-azidobenzylidene) -4-methylcyclohexanone, 2- Phenyl-1,2-butadion-2- (o-methoxycarbonyl) oxime, 1,3-diphenylpropanetrione-2- (o-ethoxycarbonyl) oxime, N-phenylglycine, tetrabutylammonium (+1) n-butyl Triphenylborate (1-), naphthalenesulfonyl chloride, quinolinesulfonyl chloride, N-phenylthioacridone, 4,4-azobisisobutyronitrile, benzthiazole disulfide, triphenylphosphine, carbon tetrabromide, Examples include combinations of photoreducing dyes such as tribromophenyl sulfone, benzoyl peroxide and eosin, and methylene blue with reducing agents such as ascorbic acid and triethanolamine.

  In the present invention, one or more of these can be used. A photoinitiator is added in 0.05-10 mass parts with respect to the photosensitive organic component, More preferably, it is 0.1-10 mass parts. If the amount of the polymerization initiator is too small, the photosensitivity will be poor, and if the amount of the photopolymerization initiator is too large, the residual ratio of the exposed portion may be small.

A sensitizer can be used together with a photopolymerization initiator to improve sensitivity and to expand the effective wavelength range for the reaction.
Specific examples of the sensitizer include 2,3-bis (4-diethylaminobenzal) cyclopentanone, 2,6-bis (4-dimethylaminobenzal) cyclohexanone, and 2,6-bis (4-dimethylamino). Benzal) -4-methylcyclohexanone, 4,4-bis (dimethylamino) chalcone, 4,4-bis (diethylamino) chalcone, p-dimethylaminocinnamylidene indanone, p-dimethylaminobenzylidene indanone, 2- (P-dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminophenylvinylene) isonaphthothiazole, 1,3-bis (4-dimethylaminobenzal) acetone, 1,3-carbonylbis (4-Diethylaminobenzal) acetone, 3,3-carbonylbis (7-diethyl) Aminocoumarin), triethanolamine, methyldiethanolamine, triisopropanolamine, N-phenyl-N-ethylethanolamine, N-phenylethanolamine, N-tolyldiethanolamine, methyl 4-dimethylaminobenzoate, 4-dimethylaminobenzoic acid Ethyl, dimethylaminobenzoate isoamyl, diethylaminobenzoate isoamyl, benzoate (2-dimethylamino) ethyl, 4-dimethylaminobenzoate (n-butoxy) ethyl, 4-dimethylaminobenzoate 2-ethylhexyl, 3-phenyl- Examples include 5-benzoylthiotetrazole and 1-phenyl-5-ethoxycarbonylthiotetrazole.

  In the present invention, one or more of these can be used. When adding a sensitizer to the photosensitive paste of this invention, the addition amount is 0.05-10 mass parts normally with respect to the photosensitive organic component, More preferably, it is 0.1-10 mass parts. If the amount of the sensitizer is too small, the effect of improving the photosensitivity is not exhibited, and if the amount of the sensitizer is too large, the residual ratio of the exposed portion may be reduced.

  Furthermore, since the photosensitive organic component contains a compound having an absorption maximum in a wavelength region exceeding 400 nm and a bis (alkylamino) benzophenone or thioxanthone derivative, the curing of the bottom of the pattern can be promoted, thereby increasing the development time. However, the pattern does not peel from the substrate, and the process margin can be widened. Also, processing with a thick film is possible.

  Specific examples of the compound having an absorption maximum in a wavelength region exceeding 400 nm include 1-chloro-N-methylacridone, 2-chloro-N-methylacridone, 3-chloro-N-methylacridone, 2- Chloro-N-butylacridone, 2-chloro-N-methylacridone, 3-chloro-N-benzylacridone, 4-chloro-N-methylacridone, 2,3-dichloro-N-methylacridone, Examples include, but are not limited to, 2,6-dichloro-N-butylacridone, N-benzylacridone, N-butylacridone, N-ethylacridone, and other acridone derivatives.

  Specific examples of bis (alkylamino) benzophenone or thioxanthone derivatives include 2-methylthioxanthone, 2-chlorothioxanthone, 2-isopropylthioxanthone, 2-laurylthioxanthone, 3-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4 -Diethylthioxanthone, 2,4-diisopropylthioxanthone, 4,4-bis (diethylamino) benzophenone, 4,4-bis (dimethylamino) benzophenone, 4,4-bis (dipropylamino) benzophenone and the like.

  In the photosensitive dielectric paste of the present invention, it is also effective to add an ultraviolet absorber. In the photosensitive paste of the present invention, soft magnetic powders and glass powders having different properties are used as inorganic powders. Therefore, the exposure light is largely scattered inside the photosensitive paste film, and the pattern tends to easily spread. By adding the ultraviolet absorber, the scattered light inside the photosensitive paste due to the exposure light is absorbed, the scattered light is weakened, and a sharp pattern can be obtained. Examples of the ultraviolet absorber include benzophenone compounds, cyanoacrylate compounds, salicylic acid compounds, benzotriazole compounds, indole compounds, inorganic fine-particle metal oxides, and the like. Among these, benzophenone compounds, cyanoacrylate compounds, benzotriazole compounds, and indole compounds are particularly effective. Specific examples thereof include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxy-5-sulfobenzophenone, 2-hydroxy-4-methoxy-2′-carboxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone trihydrate, 2 -Hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2 ', 4,4'-tetrahydroxybenzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4 -(2-hydroxy-3-methyl (Chryloxy) propoxybenzophenone, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole, 2- (2 '-Hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3', 5'-di-t-butylphenyl) -5-chlorobenzo Triazole, 2- (2′-hydroxy-4′-n-octoxyphenyl) benzotriazole, 2-ethylhexyl-2-cyano-3,3-diphenyl acrylate, 2-ethyl-2-cyano-3,3-diphenyl BONASORB UA-3901 (made by Orient Chemical Co., Ltd.) and BONASORB are acrylate and indole-based absorbents A-3902 (manufactured by Orient Chemical Industries, Ltd.), but such SOM-2-0008 (manufactured by Orient Chemical Co., Ltd.) without limitation. Furthermore, a methacryl group or the like may be introduced into the skeleton of these ultraviolet absorbers and used as a reaction type. In the present invention, one or more of these can be used.

  The addition amount of the ultraviolet absorber is in the range of 0.001 to 10 parts by mass, more preferably 0.005 to 5 parts by mass in the photosensitive dielectric paste. Beyond these ranges, the transmission limit wavelength and the wavelength gradient width change, so that the ability to absorb scattered light is insufficient, the transmittance of exposure light is lowered, and the sensitivity of the photosensitive paste is lowered.

  It is also effective to use organic dyes as ultraviolet absorbers. When using an organic dose, it absorbs scattered light inside the photosensitive dielectric paste, and in addition to the effect of weakening the scattered light, coloring is performed by adding a dye to improve visibility, and the paste remains during development. It is easy to distinguish between the removed part and the removed part. Although it does not specifically limit as organic dye, The thing which does not remain in the insulating film after baking is preferable. Specifically, anthraquinone dyes, indigoid dyes, phthalocyanine dyes, carbonium dyes, quinoneimine dyes, methine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, phthalimides A dye, perinone dye or the like can be used. In particular, it is preferable to select a carbonium-based dye such as basic blue that absorbs light having wavelengths in the vicinity of the h-line and i-line, for example, because the effects of the present invention are more easily exhibited. The amount of organic dye added is preferably 0.001 to 1% by weight.

  Furthermore, it is also effective to add a polymerization inhibitor in the photosensitive dielectric paste of the present invention. By adding a polymerization inhibitor, the polymerization inhibitor captures radicals and a photoreaction occurs suddenly at an exposure amount that cannot be suppressed by the polymerization inhibitor, thereby increasing the solubility and insoluble contrast in the developer. Can do.

  Specifically, hydroquinone, phenothiazine, pt-butylcatechol, 2,5-dibutylhydroquinone, mono-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, N-phenylnaphthylamine, 2,6- Examples thereof include, but are not limited to, di-t-butyl-p-methylphenol, chloranil, hydroquinone monomethyl ether, and pyrogallol. In the present invention, one or more of these can be used.

  The addition amount of a polymerization inhibitor is 0.1-30 mass parts in a photosensitive paste, More preferably, it is the range of 0.5-20 mass parts. If it is less than these ranges, the contrast of dissolution and insolubility in the developer is small, and if this range is exceeded, the sensitivity of the photosensitive paste decreases, requiring a large amount of exposure, and the degree of polymerization does not increase and the pattern shape Cannot be maintained.

  In the present invention, the pattern shape can be controlled by controlling the ultraviolet absorber and the polymerization inhibitor.

  An organic solvent is used to adjust the viscosity at the time of applying the photosensitive dielectric paste to the substrate according to the application method. As the organic solvent used at this time, methyl ethyl ketone, dioxane, acetone, cyclohexanone, cyclopentanone, isobutyl alcohol, isopropyl alcohol, tetrahydrofuran, dimethyl sulfoxide, γ-butyrolactone, bromobenzene, chlorobenzene, dibromobenzene, dichlorobenzene, Bromobenzoic acid, chlorobenzoic acid, etc., diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 2-ethyl- 1,3-hexanediol, terpineol, 3-methyl-3-methoxybutanol, texanol, benzyl alcohol, Propylene glycol monoethyl ether, tripropylene glycol monomethyl ether, the organic solvent mixture containing one or more of propylene glycol monomethyl ether acetate and they can be used.

  In addition, in the photosensitive dielectric paste of the present invention, a dispersant, a thixotropic agent, a plasticizer, and the like can be appropriately used depending on the purpose.

The photosensitive dielectric paste of the present invention is prepared by preparing various components so as to have a predetermined composition, and then pre-dispersing with a mixer such as a planetary mixer, and then homogenizing with a dispersing and kneading means using a disperser such as a three-roller. To make.
The photosensitive dielectric paste thus obtained can be patterned as follows.

  First, a photosensitive dielectric paste is applied by a screen printing method or the like on a low-temperature multilayer substrate or a ceramic green sheet made of alumina, aluminum nitride, glass ceramics, or the like after sintering on which a wiring conductor layer is formed. Further, the conductor formation process and the dielectric layer formation are repeated according to the required number of layers, thereby forming a multilayer substrate incorporating the dielectric layers. This low-temperature multilayer substrate made of glass / ceramics can be produced using inorganic powder for low-temperature firing. At this time, the wiring conductor layer is formed by a sputtering method, a plating method, a screen printing method, a photosensitive paste method, or the like according to the accuracy of the wiring pattern. Moreover, Cu, Au, Ag, Pd, Ag-Pd, W, Mo, etc. are suitably selected as a conductor metal.

  The coating thickness can be appropriately adjusted depending on the number of coatings, the screen mesh, the paste viscosity, etc., but is usually 3 to 150 μm. If it is less than 3 μm, it is difficult to form a dense film uniformly and it is difficult to maintain excellent dielectric properties. On the other hand, if the thickness exceeds 150 μm, it becomes difficult to transmit exposure light during exposure, and thus it becomes difficult to form a via hole.

  Subsequently, the film applied on the substrate is dried. Drying is performed by using an optional oven such as a ventilating oven, a hot plate, or an IR drying furnace to form a coating film. After drying, exposure is performed using an exposure apparatus. A proximity exposure machine or the like can be used as the exposure apparatus. Moreover, when performing exposure of a large area, after apply | coating the photosensitive paste on a board | substrate and exposing while conveying, a large area can be exposed with the exposure machine of a small exposure area. After exposure, development is performed using the difference in solubility between the exposed portion and the unexposed portion in the developer. In this case, a dipping method, a spray method, a brush method, or the like can be used. As the developer, an organic solvent in which an organic component in the photosensitive paste can be dissolved, purified water, an aqueous alkaline solution, or the like can be used. As the alkaline aqueous solution, sodium hydroxide, sodium carbonate, calcium hydroxide aqueous solution or the like can be used. However, it is preferable to use an organic alkaline aqueous solution because an alkaline component can be easily removed during firing. As the organic alkali, a general amine compound can be used. Specific examples include tetramethylammonium hydroxide, trimethylbenzylammonium hydroxide, monoethanolamine, and diethanolamine. The concentration of the alkaline aqueous solution is usually 0.05 to 5% by weight, more preferably 0.1 to 1% by weight. If the alkali concentration is too low, the soluble portion is not removed, and if the alkali concentration is too high, the pattern portion may be peeled off and the non-soluble portion may be corroded. The development temperature during development is preferably 20 to 50 ° C. in terms of process control.

  Next, a conductor is embedded in the power supply layer in the via hole (or through hole) using a conductive paste. The embedding is performed by screen printing, a dispenser, a roller, or the like using the same or different copper, silver, silver-palladium, tungsten, molybdenum, or gold conductor paste used for forming the wiring pattern. The filling of the conductor paste into the via hole of the dielectric layer is repeated every number of layers.

  Finally, firing is performed in a firing furnace to form a multilayer dielectric layer in which via-hole conductors are formed. The firing atmosphere and temperature vary depending on the type of paste and substrate, but firing is performed in an atmosphere of air, nitrogen, hydrogen, or the like. As the firing furnace, a batch-type firing furnace, a belt-type continuous firing furnace, or the like can be used. The firing temperature is 600 to 1000 ° C.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited by these Examples.

(Measurement of water absorption)
Using Hiranuma Sangyo Co., Ltd. trace moisture content measuring device AQ-7 and moisture vaporization accessory device EV-6, heating vaporization method at 200 ° C (sample is vaporized by heating at 200 ° C, and this is dried nitrogen gas The measurement was conducted by a method of guiding to a hand-defined cell and measuring.

(Relative permittivity)
First, a solid aluminum film was formed on a substrate (99.6% alumina substrate, 76 mm square, thickness 0.635 mm) by vapor deposition. Next, the entire surface of the photosensitive dielectric paste was applied using a Microtec screen printer and a 380 mesh screen plate, and baked at 850 ° C. to form a dielectric layer. Further, a solid aluminum film is formed thereon by vapor deposition, and the capacitance is measured at 23 ° C. and 1 MHz with an LCR meter (“HP4284A” manufactured by Yokogawa Hewlett-Packard Co.) to determine the relative dielectric constant (ε _g ) of the glass. Was calculated.

ε _g = Cd / ε ₀ S
(Limit resolution)
The entire surface was applied onto a substrate (99.6% alumina substrate, 76 mm square, thickness 0.635 mm) using a Microtec screen printer and a 380 mesh screen plate, and 100 using a hot air dryer manufactured by Tabai. Dry at 30 ° C. for 30 minutes. The film thickness after drying was 20 μm. After drying, exposure was performed through a photomask (6, 8, 10, 12, 15, 20, 25, 30, 40, 50 μmφ arranged in a 50 μm pitch) on which a resolution test pattern was formed. As the exposure machine, a Dainippon Screen exposure machine (light source: 2 kW super high pressure mercury lamp) was used. After exposure, a 0.1% 2-aminoethanol aqueous solution was used for development for 1 minute in a shower to obtain a pattern (developer temperature was 25 ° C.). Then, it baked using the roller hearth baking furnace by Koyo Thermotech Co., Ltd. for 10 minutes at 850 degreeC. After firing, the resolution was examined using an electron microscope (manufactured by Keyence Corporation, VE-7800).

(Development margin)
The entire surface was applied onto a substrate (99.6% alumina substrate, 76 mm square, thickness 0.635 mm) using a Microtec screen printer and a 380 mesh screen plate, and 100 using a hot air dryer manufactured by Tabai. Dry at 30 ° C. for 30 minutes. The film thickness after drying was 20 μm. After drying, exposure was performed through a photomask (6, 8, 10, 12, 15, 20, 25, 30, 40, 50 μmφ arranged in a 50 μm pitch) on which a resolution test pattern was formed. As the exposure machine, a Dainippon Screen exposure machine (light source: 2 kW super high pressure mercury lamp) was used. After the exposure, a 0.1% 2-aminoethanol aqueous solution was used for development with a shower, and the time for the unexposed portion to dissolve on the substrate was measured with a stopwatch. And it was measured how many times the dissolution time of the unexposed part peeled from the substrate.

(Examples 1-14, Comparative Examples 1-3)
Each material was measured, mixed and kneaded with three rollers, and 17 types of photosensitive dielectric pastes were obtained (Paste Nos. 1 to 17). Table 2 shows the results of examining the water absorption, relative dielectric constant, limit resolution, and development margin of the obtained photosensitive dielectric paste.

  The materials used in Table 1 are as follows.

A: Softening point 795 made of SiO ₂ (38), Al ₂ O ₃ (35), B ₂ O ₃ (9), MgO (5), CaO (5), BaO (5), and other oxides (3). Glass powder B: SiO ₂ (63), Al ₂ O ₃ (4), B ₂ O ₃ (12), MgO (15), glass powder B, center particle diameter 1 μm, maximum particle diameter 5 μm, relative dielectric constant 7.1 Glass powder C: C: ZnO (52) having a softening point of 730 ° C., a center particle diameter of 1.2 μm, a maximum particle diameter of 6 μm, and a relative dielectric constant of 4.5 consisting of K ₂ O (2) and other oxide (4) Softening point 545 ° C., center particle diameter 1.2 μm, maximum particle diameter 5 μm made of SiO ₂ (9), B ₂ O ₃ (26), BaO (9), K ₂ O (2) and other oxides (2) , Glass powder D having a relative dielectric constant of 7.4: center particle diameter of 1.5 μm, maximum particle diameter of 5 μm, relative dielectric constant of 124 4 Barium titanate (manufactured by Kyoritsu Material Co., Ltd.)
E: Strontium titanate having a center particle diameter of 0.3 μm, a maximum particle diameter of 6 μm, and a relative dielectric constant of 338 (manufactured by Sakai Chemical Industry Co., Ltd.)
F: Photosensitive acrylic polymer having an acid value of 85 and a weight average molecular weight of 32,000 (APX-716, manufactured by Toray Industries, Inc.)
G: Propylene oxide modified trimethylolpropane triacrylate (Daiichi Kogyo Seiyaku Co., Ltd.)
H: Isomyristyl acrylate (manufactured by Kyoeisha Chemical)
I: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (Ciba Specialty Chemicals, IC-369)
J: 4,4-bis (diethylamino) benzophenone K: 2,4-diethylthioxanthone L: N-butylacridone M: Basic blue 26
N: p-methoxyphenol O: diethylene glycol monobutyl ether acetate In Examples 1 to 16, the dielectric layer was sufficiently densified by relatively low temperature firing (fired at 850 ° C.), low water absorption. It also showed high dielectric constant and high resolution.

  In particular, in Examples 3 and 4 in which glass powders having different softening points within a specific range were combined, the water absorption was lower and the denseness was further improved. In Examples 9 and 11, since many glasses having a low softening point were used, the pattern shape after firing was distorted, and although the resolution was slightly reduced, the water absorption was low and the dielectric layer was sufficiently densified. . Further, in Examples 14 to 16 in which the photosensitive organic component does not include a compound having an absorption maximum in a wavelength region exceeding 400 nm and bis (alkylamino) benzophenone or a thioxanthone derivative, the resolution is reduced, but the water absorption is also low. The dielectric layer was sufficiently densified. Moreover, the high dielectric constant was shown.

  On the other hand, in Comparative Example 1, since there was no glass, there was no denseness, and water absorption and relative permittivity could not be measured. In Comparative Example 2, the water absorption was low, the dielectric layer was sufficiently densified, and showed a high dielectric constant and high resolution, but a high firing temperature was necessary. In Comparative Example 3, since the glass ratio was small, the water absorption was high and the relative dielectric constant could not be measured. In Comparative Example 4, the water absorption was low and the dielectric layer was densified, but the relative dielectric constant was small because the ratio of the dielectric powder was small.

Claims (5)

A photosensitive paste comprising an inorganic powder and a photosensitive organic component, wherein the inorganic powder is a dielectric powder (A) having a relative dielectric constant of 100 or more, a relative dielectric constant of 50 or less, and a softening point of 500 to 900 ° C. 1 to 70 mass% of SiO _{2 in} oxide conversion notation
Al ₂ O ₃ 3~50 wt%
B ₂ O ₃ 4 to 20 wt%
MgO 1-20% by mass
And wherein _{CaO, BaO, TiO 2, PbO} , Bi 2 O 3, Li 2 O, the glass powder (B) to at least one compound of the _{K 2} O and Na2O containing 0.1 to 10 mass%, the dielectric The mass ratio of the body powder (A) and the glass powder (B) is in the range of 55:45 to 85:15 , and the dielectric powder (A) is barium titanate, calcium titanate, strontium titanate And at least one dielectric powder selected from the group consisting of calcium zirconate and a photosensitive dielectric paste. The photosensitive dielectric paste according to claim 1, wherein the dielectric powder has a relative dielectric constant of 800 or more. The photosensitive dielectric paste according to claim 1 or 2 , wherein the center particle diameter (D50) of the dielectric powder and the glass powder is in the range of 0.1 to 3 µm, and the maximum particle diameter is 8 µm or less. Photosensitive compound organic component has an absorption maximum in a wavelength region beyond the 400nm and bis (alkylamino) benzophenone or claim 1-3 photosensitive paste according to any one, characterized in that it comprises a thioxanthone derivative. The photosensitive dielectric paste A method of manufacturing an electronic circuit component comprising the step of drying the coated substrate, the photosensitive dielectric paste according to any one of claims 1-4 in the photosensitive dielectric paste A method of manufacturing an electronic circuit component, wherein the electronic circuit component is used.