KR102667680B1 - Photosensitive composition, composite, electronic component and electronic component manufacturing method - Google Patents

Abstract

A photosensitive composition capable of reducing the generation of residue between lines while shortening development time is provided. According to the present invention, a photosensitive composition containing noble metal powder, a photopolymerizable compound, a photopolymerization initiator, and a dispersant is provided. The dispersant has a solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more.

Description

Photosensitive composition, composite, electronic component, and method of manufacturing electronic component {PHOTOSENSITIVE COMPOSITION, COMPOSITE, ELECTRONIC COMPONENT AND ELECTRONIC COMPONENT MANUFACTURING METHOD}

The present invention relates to photosensitive compositions and their uses. Specifically, it relates to photosensitive compositions, composites, electronic components, and methods for producing electronic components.

Conventionally, a method of forming a conductive layer or a resin insulating layer on a substrate is known by photocuring a photosensitive composition containing a photopolymerizable compound and a photopolymerization initiator (see Patent Documents 1 and 2). For example, Patent Document 1 discloses forming a conductive layer made of a non-metal on a substrate by a photolithography method. In this method, first, a photosensitive composition is applied on a substrate, dried, and a film-like body is formed (film-like body forming process). Next, the molded film body is covered with a photomask having a predetermined opening pattern, and the film body is exposed to light through the photomask (exposure process). By this, the exposed portion of the film-like body is photocured. Next, the unexposed portion that was shielded from light by the photomask is removed by etching with an alkaline aqueous developer (development process). Then, the film-like body with the desired development pattern is fired (baking process). According to the photolithography method including the above steps, a finer conductive layer can be formed compared to various conventional printing methods.

Japanese Patent No. 3975932 Japanese Patent Application Publication No. 2015-161815

However, recently, miniaturization and high performance of various electronic devices have rapidly progressed, and further miniaturization and higher density of electronic components mounted on electronic devices have been required. Accordingly, in the manufacture of electronic components, there is a demand for thinner lines as well as lower resistance of the conductive layer. For example, it is required to form a conductive layer in which the line width of the wiring constituting the conductive layer and the space between adjacent wirings (line and space: L/S) are 30 μm/30 μm or less, and further, 20 μm/20 μm or less. there is.

However, according to the present inventor's examination, when the viscosity of the photopolymerizable compound used is high, for example, when the photopolymerizable compound used is a polymer with a high molecular weight, the conductive layer of a fine line with a small L/S is stable. It was difficult to form. In other words, the higher the viscosity of the photopolymerizable compound, the higher the adhesion between the substrate and the unexposed portion. However, if L/S is small, it becomes difficult to supply developer solution to the space between lines during the development process. As a result, it became difficult to remove the unexposed portion, and the development time, that is, the time required to completely remove the unexposed portion (time to the break point (B.P.)), sometimes became long. In addition, as shown in the schematic diagram of FIG. 2, there were cases where residues that could not be removed by etching (hereinafter referred to as “line-to-line residues”) remained in the space portion. As a result, there were problems such as a leakage current occurring due to the tunnel effect or a connection between wires causing a short circuit. Therefore, there has been a demand from users to reduce the generation of residue between lines while shortening the development time, and to improve productivity and yield.

The present invention was made in view of these points, and its purpose is to provide a photosensitive composition that can reduce the generation of residues between lines while shortening the development time. Another related object is to provide a composite having a conductive film made of a dried product of such a photosensitive composition. Another related object is to provide an electronic component including a conductive layer made of a sintered body of such a photosensitive composition, and a method for manufacturing the same.

According to the present invention, a photosensitive composition containing noble metal powder, a photopolymerizable compound, a photopolymerization initiator, and a dispersant is provided. The dispersant has a solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more.

The photosensitive composition contains a dispersant with a high solubility parameter of 9.9 or more. This makes it easier to remove unexposed portions in the development process, thereby shortening the development time. In addition, the generation of residue between lines can be reduced, and a fine-line conductive layer with a small L/S can be formed with good reproducibility. As a result, productivity and yield can be improved.

In addition, in this specification, “Solubility Parameter (SP value)” refers to, for example, “Consideration on Solubility Parameters of Additives”, Research on Paints, No.152, pp41-46, October 2010, [online ], refers to the value measured by the turbidity titration method described in <URL: http://www.kansai.co.jp/rd/token/pdf/152/08.pdf>. Specific measurement methods are explained in the Examples section. Additionally, the unit of SP value is (cal/cm ³ ) ^1/2 .

In a preferred embodiment disclosed herein, the photopolymerizable compound includes a photopolymerizable polymer with a weight average molecular weight of 5000 or more. When the photopolymerizable compound contains a photopolymerizable polymer, it is more difficult to remove unexposed portions during the development process. Accordingly, the effect of the technology disclosed herein is better exhibited.

In a preferred embodiment disclosed herein, the photopolymerizable compound contains one or two or more compounds having an acidic group. As a result, the effect of improving the removability of unexposed portions in the development process is exhibited at a much higher level.

In a preferred embodiment disclosed herein, when the total of the noble metal powder is 100 parts by mass, the content ratio of the dispersant is 0.1 part by mass or more and 2.7 parts by mass or less. As a result, the removability of the unexposed portion and the etching resistance of the exposed portion can be balanced at a high level. That is, while improving the removal of unexposed portions in the development process, high adhesion (tackiness) to the substrate can be realized for the exposed portions.

In a preferred embodiment disclosed herein, the dispersant consists only of compounds having a solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more. This makes it more difficult for residue between lines to remain, and the space portion of the fine line can be secured more stably.

In a preferred embodiment disclosed herein, the dispersant contains one or two or more compounds having an acidic group. As a result, in the development process, unexposed portions can be removed more quickly and cleanly using an aqueous developer.

In a preferred embodiment disclosed herein, the noble metal powder contains silver-based particles. As a result, a conductive layer with an excellent balance between cost and low resistance can be realized.

Additionally, the present invention provides a composite comprising a green sheet and a conductive film disposed on the green sheet and made of a dried body of the photosensitive composition.

Moreover, according to the present invention, an electronic component provided with a conductive layer made of a sintered body of the photosensitive composition is provided. According to the photosensitive composition, a fine-line conductive layer with a small L/S can be formed with good reproducibility. For this reason, by using the photosensitive composition, electronic components with a small and/or high-density conductive layer can be suitably realized.

Furthermore, according to the present invention, a method for manufacturing an electronic component is provided, including the step of applying the photosensitive composition on a substrate, exposing and developing, and then baking to form a conductive layer made of a sintered body of the photosensitive composition. . With this manufacturing method, electronic components with small and/or high-density conductive layers can be manufactured stably, thereby improving productivity and yield.

1 is a cross-sectional view schematically showing the structure of a multilayer chip inductor according to an embodiment of the present invention.
Figure 2 is a schematic diagram for explaining residues between lines.

Hereinafter, preferred embodiments of the present invention will be described. In addition, matters other than those specifically mentioned in this specification (e.g., composition of the photosensitive composition) are matters necessary for practicing the present invention (e.g., method of preparing the photosensitive composition, method of forming a conductive film or conductive layer, electronic components). manufacturing method, etc.) can be understood based on the technical content taught in this specification and the general technical knowledge of those skilled in the art. The present invention can be implemented based on the content disclosed in this specification and common technical knowledge in the field.

In addition, in the following description, a film-like body (dried product) obtained by drying the photosensitive composition at a temperature below the boiling point of the dispersant, specifically, approximately 200°C or below, for example, 100°C or below, is referred to as a “conductive film.”

The conductive film includes the entire unbaked (before firing) film-like body. The conductive film may be an uncured product before photocuring, or may be a cured product after photocuring. In addition, in the following description, the sintered body (fired product) obtained by firing the photosensitive composition at a temperature equal to or higher than the sintering temperature of the noble metal powder is referred to as a “conductive layer.” The conductive layer includes wiring (linear body), a wiring pattern, and a beta pattern.

In addition, in this specification, the notation “A to B” indicating a range means A to B or less.

≪Photosensitive composition≫

The photosensitive composition disclosed herein is suitably used in the production of layers made of noble metals, such as conductive layers and heat dissipation layers. The photosensitive composition disclosed herein contains precious metal powder, a photopolymerizable compound, a photopolymerization initiator, and a dispersant as essential components. Hereinafter, each component will be described in order.

＜Precious metal powder＞

Noble metal powder is a component that provides electrical conductivity to a conductive layer obtained by, for example, baking a photosensitive composition. There is no particular limitation on the noble metal powder, and one or two or more types can be appropriately selected and used among conventionally known powders, for example, depending on the intended use. Suitable examples of precious metal powder include metals such as gold (Au), silver (Ag), platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru), and osmium (Os). Examples include simple substances, mixtures and alloys thereof. Examples of the alloy include silver alloys such as silver-palladium (Ag-Pd), silver-platinum (Ag-Pt), and silver-copper (Ag-Cu).

In one suitable embodiment, the precious metal powder includes silver-based particles. Silver is relatively cheap and has high electrical and thermal conductivity. For this reason, when the noble metal powder contains silver particles, for example, a conductive layer with an excellent balance between cost and low resistance can be realized.

In addition, in this specification, "silver particle" includes all things containing a silver component. Examples of silver-based particles include silver alone, the above-mentioned silver alloy, core-shell particles having silver-based particles as the core, for example, silver-ceramic core-shell particles, etc.

Although not particularly limited, the D ₅₀ particle size of the precious metal powder (particle size corresponding to 50% of the integrated value from the side with the smaller particle size in the volume-based particle size distribution based on the laser diffraction/scattering method.) is the exposure in the exposure process. From a balance with performance, generally 1 to 5 μm is sufficient. By setting the D ₅₀ particle size within the above range, the exposure performance of the exposed portion can be improved and a fine line can be formed more stably. From the viewpoint of suppressing aggregation in the photosensitive composition and improving stability, the D ₅₀ particle size of the noble metal powder may be, for example, 1.5 μm or more or 2 μm or more. In addition, from the viewpoint of improving fine wire formation, densification of the conductive layer, and lowering the resistance, the D ₅₀ particle size of the precious metal powder is, for example, 4.5 μm or less, 4 μm or less. You can continue.

The precious metal powder may have an organic surface treatment agent adhered to its surface. The organic surface treatment agent is at least one of, for example, improving the dispersibility of the precious metal powder in the photosensitive composition, increasing the affinity between the precious metal powder and other contained components, and preventing surface oxidation of the metal constituting the noble metal powder. It can be used for various purposes. Examples of organic surface treatment agents include fatty acids such as carboxylic acid and benzotriazole-based compounds.

Although not particularly limited, the proportion of noble metal powder in the entire photosensitive composition may be generally 50% by mass or more, typically 60 to 95% by mass, for example, 70 to 90% by mass. By satisfying the above range, a conductive layer with excellent density and electrical conductivity can be suitably formed. Additionally, the handling of the photosensitive composition and workability when forming a conductive film can be improved.

＜Photopolymerizable compound＞

A photopolymerizable compound is a photocurable component that is cured by causing a polymerization reaction, crosslinking reaction, etc. by active species generated by decomposition of a photopolymerization initiator, which will be described later. The polymerization reaction may be, for example, addition polymerization or ring-opening polymerization. The photopolymerizable compound is not particularly limited, and one or two or more types can be appropriately selected and used from among conventionally known compounds, for example, depending on the intended use or type of substrate. A photopolymerizable compound typically has one or more unsaturated bonds and/or cyclic structures. Suitable examples of photopolymerizable compounds include radically polymerizable compounds having one or more ethylenically unsaturated bonds such as a (meth)acryloyl group or vinyl group, and cationically polymerizable compounds having a cyclic structure such as an epoxy group.

In this specification, the photopolymerizable compound includes a photopolymerizable monomer with a weight average molecular weight of less than 1500, a photopolymerizable oligomer with a weight average molecular weight of 1500 to less than 5000, and a photopolymerizable polymer with a weight average molecular weight of 5000 or more.

In addition, in this specification, “weight average molecular weight” refers to the average molecular weight based on weight measured by gel chromatography (Gel Permeation Chromatography: GPC) and converted using a standard polystyrene calibration curve.

In one suitable embodiment, the photopolymerizable compound includes a photopolymerizable polymer with a weight average molecular weight of 5000 or more. Photopolymerizable polymers can be cured with a relatively small amount of exposure compared to monomers or oligomers. For this reason, even the deep portion of the exposed portion (portion close to the base material) can be stably cured. Therefore, by including a photopolymerizable polymer, the adhesion between the base material and the conductive layer increases, and the occurrence of defects such as peeling and disconnection in the conductive layer can be appropriately suppressed. Additionally, the water resistance and durability of the conductive layer can be improved. In addition, when the photopolymerizable compound contains a photopolymerizable polymer, the adhesion (tackiness) to the substrate increases, and the removability of the unexposed portion in the development process decreases. For this reason, application of the technology disclosed herein is effective. The weight average molecular weight of the photopolymerizable compound is generally 10,000 or more, typically 15,000 or more, for example, 20,000 or more, and may be generally 100,000 or less, for example, 50,000 or less. The photopolymerizable compound preferably contains, in addition to the photopolymerizable polymer, at least one of a photopolymerizable monomer and a photopolymerizable oligomer.

In one suitable embodiment, the photopolymerizable compound contains a monomer having a (meth)acryloyl group or a (meth)acrylate with the monomer as a structural unit. When the photopolymerizable compound contains (meth)acrylate, the flexibility of the conductive layer and its followability to the substrate can be improved. As a result, the occurrence of defects such as peeling and disconnection can be better suppressed. A suitable example of a (meth)acrylate is a homopolymer of alkyl (meth)acrylate, or a homopolymer containing alkyl (meth)acrylate as the main monomer and a minor monomer having copolymerization with the main monomer. A copolymer may be mentioned.

In addition, in this specification, “(meth)acryloyl” includes “methacryloyl” and “acryloyl”, and “(meth)acrylate” includes “methacrylate” and “acrylate.” It is a term that includes.

In one suitable embodiment, the double bond equivalent weight (calculated value calculated as weight average molecular weight/number of C=C double bonds) of the (meth)acrylate is generally 200 or more, typically 300 or more, for example 400 or more, Furthermore, it is 450 or more, and is generally 1000 or less, for example, 500 or less. If the double bond equivalent is within the above range, the removability of the unexposed portion and the etching resistance of the exposed portion can be balanced at a high level in the development process. In other words, the development time can be further shortened, and the occurrence of defects such as peeling and disconnection can be better suppressed.

In one suitable embodiment, (meth)acrylate contains a monomer having a (meth)acryloyl group and an ionic functional group (for example, an acidic group) as a structural unit. As a result, the removability of the uncured portion can be effectively improved, and the effect of the technology disclosed here can be exhibited at a higher level. Specific examples of (meth)acrylates having ionic functional groups other than (meth)acryloyl groups include (meth)acrylates containing carboxyl groups, (meth)acrylates containing phosphoric acid groups, acid-modified epoxy (meth)acrylates, and urethane-modified epoxy (meth)acrylate containing a carboxyl group. Among these, it is preferable to include a monomer containing a (meth)acryloyl group and a carboxyl group or a (meth)acrylate using the monomer as a structural unit. Examples of commercially available products of such (meth)acrylates include Cychromer P (trademark) ACA Z200M, Z230AA, Z250, Z251, Z300, Z320, and Z254F manufactured by Daicel Allnex Co., Ltd.

In one suitable embodiment, the photopolymerizable compound includes a photopolymerizable compound (urethane bond-containing compound) having a urethane bond (-NH-C(=O)-O-). For example, the above photopolymerizable polymer may be a urethane bond-containing polymer having a urethane bond, or, in addition to the above photopolymerizable polymer, a urethane bond-containing monomer having a urethane bond or a urethane bond-containing oligomer having a urethane bond may be used. It may be included. When the photopolymerizable compound contains a urethane bond-containing compound, it is possible to further improve the etching resistance of the exposed portion and to realize a conductive layer with even greater flexibility and elasticity. Therefore, the adhesion between the base material and the conductive layer can be improved, and the occurrence of defects such as peeling and disconnection can be suppressed to a high level. Suitable examples of the urethane bond-containing compound include urethane-modified (meth)acrylate and urethane-modified epoxy.

In one suitable embodiment, the photopolymerizable compound contains a compound having an acidic group. For example, the resin acid value is generally 30 mgKOH/g or more, typically 50 mgKOH/g or more, for example, 100 to 150 mgKOH/g. And preferably, the resin acid value of the entire photopolymerizable compound is within the above range. In other words, it is desirable that the entire photopolymerizable compound exhibits a certain acidity. If the resin acid value is more than a predetermined value, unexposed portions can be removed more quickly and cleanly using an aqueous developer in the development process. Moreover, if the resin acid value is below a predetermined value, the solubility in an aqueous developer is suppressed in the development process, and peeling and disconnection of the exposed portion can be better suppressed.

Additionally, in this specification, “acid value” refers to the content (mg) of potassium hydroxide (KOH) required to neutralize free fatty acids contained in a unit sample (1 g). The unit is mgKOH/g.

In one suitable embodiment, the SP value of the photopolymerizable compound is generally within 20 (cal/cm ³ ) ^1/2 , typically between 8 and 13 (cal/cm ³ ) ^1/2 , for example between 10 and 13 (cal). /cm ³ ) ^1/2 will do. In addition, when using multiple types of compounds as the photopolymerizable compound, the SP value of the photopolymerizable compound is the sum of the product of the SP value of each compound and the composition ratio of each compound (weighted average value). As a result, the effect of the technology disclosed here can be exhibited at a higher level while increasing the stability of the entire photosensitive composition.

In another suitable embodiment, the glass transition point (Tg value based on Differential Scanning Calorimetry (DSC)) of the photopolymerizable compound is generally 40°C or higher, typically 50°C or higher, for example, 60°C or higher. It is ℃ or higher, and further, it is 100℃ or higher, in one example, it is 120℃ or higher, 130℃ or higher, and is generally 200℃ or lower, for example, 150℃ or lower. As a result, the flexibility and adhesion of the conductive film can be further improved, and the adhesion between the base material and the conductive layer can be further improved. Moreover, when the Tg value is in the above range, the adhesion (tackiness) to the substrate increases, and the removability of the unexposed portion in the development process decreases. For this reason, application of the technology disclosed herein is effective.

Although not particularly limited, when the photopolymerizable compound contains a photopolymerizable polymer, the proportion of the photopolymerizable polymer in the entire photopolymerizable compound is generally 10% by mass or more, typically 20% by mass or more, e.g. For example, it may be 30 mass% or more, generally 90 mass% or less, typically 80 mass% or less, for example, 50 mass% or less. When the above range is satisfied, the effect of the technology disclosed herein is exhibited at a high level. Also, although not particularly limited, when the photopolymerizable compound contains at least one of a photopolymerizable monomer and a photopolymerizable oligomer, the ratio of at least one of the photopolymerizable monomer and the photopolymerizable oligomer to the entire photopolymerizable compound is based on mass. In general, it may be 10 mass% or more, typically 20 mass% or more, for example, 50 mass% or more, or generally 90 mass% or less, typically 80 mass% or less, for example, 70 mass% or less.

Although not particularly limited, the proportion of the photopolymerizable compound in the entire photosensitive composition is generally 0.1 to 50% by mass, typically 0.5 to 30% by mass, for example, 1 to 20% by mass, and further 5 to 15% by mass. That's it. In addition, although it is not particularly limited, the content ratio of the photopolymerizable compound may be generally 0.1 to 50 parts by mass, typically 0.5 to 30 parts by mass, for example, 1 to 20 parts by mass, with respect to 100 parts by mass of the precious metal powder. . By satisfying the above range, the photocurability of the photosensitive composition is appropriately exhibited, and a conductive layer can be formed stably at a high level.

＜Photopolymerization initiator＞

A photopolymerization initiator is a component that is decomposed by irradiation with active energy rays such as visible light, ultraviolet rays, or electron beams, generates active species such as radicals and cations, and initiates the reaction of the photopolymerizable compound. As a photopolymerization initiator, one or two or more types can be appropriately selected and used among conventionally known ones depending on the type of photosensitive resin, etc. As a suitable example, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) )-Butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4-diethylthioxanthone, Benzophenone, etc. can be mentioned.

Although not particularly limited, the proportion of the photopolymerization initiator in the entire photosensitive composition may be generally 0.01 to 5 mass%, typically 0.1 to 3 mass%, for example, 0.2 to 2 mass%. As a result, the photocurability of the photosensitive composition is appropriately exhibited, and the conductive layer can be formed more stably.

＜Dispersant＞

A dispersant is an essential ingredient for improving the removal of unexposed parts in the development process. In the technology disclosed herein, the dispersant has an SP value based on turbidity titration of 9.9 (cal/cm ³ ) ^1/2 or more. In addition, when using multiple types of compounds as a dispersant, the SP value of the dispersant is the sum of the products of the SP value of each compound and the composition ratio of each compound (weighted average value). SP value is a scale indicating the degree of hydrophilicity and hydrophobicity. By setting the SP value to a predetermined value or more, the “miscibility” of the water-based developer and the photosensitive composition improves. More specifically, the interaction between the resin component (for example, a photopolymerizable compound or an organic binder described later) and the precious metal powder is reduced, and the resin component and the precious metal powder become easier to dissolve in the aqueous developer. By this, the removability of the unexposed portion can be appropriately increased.

Commercially available dispersants with an SP value of 9.9 (cal/cm ³ ) ^1/2 or more include, for example, Marialim (trademark) SC1015F manufactured by Daicel Allnex Co., Ltd. and Hypermer (trademark) KD-4 manufactured by Kuroda Japan Co., Ltd. , KD-8, KD-9, etc. From the viewpoint of low cost, etc., or from the viewpoint of achieving the above-described effects with a smaller amount of use, the SP value of the dispersant should be 10.0 (cal/cm ³ ) ^1/2 or more, for example, 10.4 (cal/cm ³ ) ¹ It may be ^/2 or more. In addition, the upper limit of the SP value of the dispersant is not particularly limited, but from the viewpoint of ease of availability, etc., it is generally 30 (cal/cm ³ ) ^1/2 or less, for example, 20 (cal/cm ³ ) ^1/2 or less, for example. It may be less than 15(cal/cm ³ ) ^1/2 .

As long as the dispersant satisfies the range of the above SP value, one or two types are selected from compounds known to be usable as a dispersant for this type of application, for example, depending on the type of noble metal powder or photopolymerizable compound. You can select and use the above as appropriate. In one suitable embodiment, the dispersant contains one or two or more types of compounds having an acidic group. An acidic group is a substituent that has a dissociable proton and is acidic in water. Among them, it is preferable to include a compound having a relatively highly acidic functional group, for example, a phenolic hydroxyl group, a carboxyl group, a sulfo group, a phosphono group, a boronic acid group, etc. Acidic groups have strong coordination properties with respect to the noble metal fine particles constituting the noble metal powder. For this reason, by using a compound having an acidic group, the interaction between the acidic group of the photopolymerizable polymer and the noble metal fine particles is weakened, and the photopolymerizable polymer becomes easy to dissolve in the developer. As a result, the removability of the unexposed portion can be further improved.

A compound having an acidic group preferably has an acid value. In other words, it is an acidic compound with an acid value higher than the lower limit of detection (depending on the measurement precision, but generally 0.5 mgKOH/g or higher). The acid value of the compound having an acidic group is generally 10 to 200 mgKOH/g or more, for example, 20 to 100 mgKOH/g. As a result, the effect of the technology disclosed here can be exhibited at a higher level. Moreover, the compound having an acidic group may further have a basic group. In other words, it may be an amphoteric compound. In this case, the compound having an acidic group does not need to have an acid value.

The structure of one or two or more compounds constituting the dispersant is not particularly limited, but typically is linear, linear, or plural in a linear main skeleton (carbon chain with the largest number of carbon atoms. The same applies hereinafter). It has a branched structure in which side chains (carbon chains branching from the main chain. Hereinafter the same. For example, graft chains) are combined. Alternatively, it may have a rib-shaped structure in which a plurality of side chains are arranged along the main skeleton. At least one of the main skeleton and a plurality of side chains may have an ionic functional group.

The ionic functional group may be present in the main skeleton, or may be present at the end or in the middle of the side chain. However, the main skeleton and/or a plurality of side chains may be hydrophobic without having an ionic functional group. The main skeleton just has to be polyfunctional, having a plurality of ionic functional groups. The main skeleton may be, for example, a polycarboxylic acid having a plurality of acidic groups as described above, a polyamine having a plurality of alkaline groups, etc. The side chain may be an alkylene chain or a polyoxyalkylene chain, for example, an ethylene oxide (EO) chain or a propylene oxide (PO) chain. The side chain may be a saturated or unsaturated, linear or branched hydrocarbon chain.

The weight average molecular weight of each of one or two or more compounds constituting the dispersant is generally 100 or more, typically 500 or more, for example 1000 or more, and usually 100,000 or less, typically 50,000 or less, for example. For example, it can be less than 30,000. By setting it within the above range, the coordination property for micron-sized noble metal fine particles can be improved. Additionally, the viscosity of the photosensitive composition can be suppressed and the removability of unexposed parts can be improved. Therefore, the effect of the technology disclosed here can be exhibited at a higher level.

Among the dispersants, the proportion of compounds with a solubility parameter of less than 9.9 (cal/cm ³ ) ^1/2 may be suppressed to a low level. For example, the content ratio of compounds with a solubility parameter of less than 9.9 (cal/cm ³ ) ^1/2 is generally less than 50% by mass, preferably 40% by mass or less, more preferably 10% by mass, of the total compounds constituting the dispersant. It may be % by mass or less, and it is particularly preferable that it does not contain compounds with a solubility parameter of less than 9.9 (cal/cm ³ ) ^1/2 . In other words, it is particularly preferable that the dispersant consists only of compounds with a solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more. As a result, it becomes more difficult for residue between lines to remain in the space portion, and fine lines can be formed stably. In other words, fine line formation can be further improved. Therefore, the effect of the technology disclosed here can be exhibited at a higher level.

In one suitable embodiment, the absolute value of the difference between the SP values of water and the dispersant, that is, | SP value of water - SP value of dispersant |, is generally within 13.6 (cal/cm ³ ) ^1/2 , typically 13.5 (cal). /cm ³ ) within ^1/2 , for example, within 13.1(cal/cm ³ ) ^1/2 . By this, the affinity with the aqueous developer can be further increased, and the removability of the unexposed portion can be further improved.

In another suitable embodiment, the absolute value of the difference between the SP values of the photopolymerizable compound and the dispersant, that is, | SP value of the photopolymerizable compound - SP value of the dispersant |, is generally within 13 (cal/cm ³ ) ^1/2 , Typically, it is within 10 (cal/cm ³ ) ^1/2 , for example, within 8 (cal/cm ³ ) ^1/2 , and in one example, within 5 (cal/cm ³ ) ^1/2 .

As a result, the effect of the technology disclosed here can be exhibited at a higher level while increasing the stability of the entire photosensitive composition.

Although not particularly limited, the proportion of the dispersant in the entire photosensitive composition may be generally 0.01 to 5 mass%, typically 0.1 to 3 mass%, for example, 0.2 to 2 mass%. This makes it easier to remove unexposed portions in the development process, and the generation of residues between lines can be better suppressed. Additionally, a conductive layer with excellent density and electrical conductivity can be formed. In addition, although it is not particularly limited, the content ratio of the dispersant may be approximately 0.01 to 10 parts by mass, typically 0.05 to 5 parts by mass, and preferably 0.1 to 2.7 parts by mass, with respect to 100 parts by mass of the noble metal powder. As a result, the removability of the unexposed portion and the etching resistance of the exposed portion can be achieved at a high level of balance. In other words, it is possible to improve the removability of the unexposed portion in the development process while achieving high adhesion (tackiness) to the substrate for the exposed portion.

＜Organic binder＞

The photosensitive composition may contain an organic binder in addition to the essential components described above. The organic binder is a component that improves the adhesion between the substrate and the conductive film (uncured product) before photocuring. As the organic binder, one or two or more types can be appropriately selected and used among conventionally known binders, depending on, for example, the type of substrate or the type of photopolymerizable compound. The organic binder is preferably one that can be easily removed with an aqueous developer in the development process. For example, when using an alkaline aqueous developer in the development process, an alkali-soluble resin, for example, a compound having an acidic group as described above, is preferable. This makes it easier to remove unexposed portions in the development process.

Suitable examples of organic binders include cellulose-based polymer compounds such as methylcellulose, ethylcellulose, carboxymethylcellulose, and hydroxymethylcellulose, acrylic resins, phenol resins, alkyd resins, polyvinyl alcohol, and polyvinyl butyral. there is. Among them, cellulose-based polymer compounds are preferable from the viewpoint of ease of removal in the development process.

When an organic binder is included in the photosensitive composition, there is no particular limitation, but the proportion of the organic binder in the entire photosensitive composition is generally 0.1 to 20% by mass, typically 0.5 to 10% by mass, for example, 1 to 5% by mass. It can be %.

＜Organic dispersion medium＞

In addition to the essential components described above, the photosensitive composition may contain an organic dispersion medium that disperses these components. The organic dispersion medium is a component that provides appropriate viscosity and fluidity to the photosensitive composition, improves the handleability of the photosensitive composition, and improves workability when forming a conductive film. As an organic dispersion medium, one or two or more types can be appropriately selected and used from among conventionally known ones, for example, depending on the type of photopolymerizable compound.

As a suitable example of an organic dispersion medium, alcohol-based solvents such as terpineol, dihydroterpineol (mentanol), texanol, 3-methyl-3-methoxybutanol, and benzyl alcohol; ethylene glycol, propylene glycol, Glycol-based solvents such as ethylene glycol; ethers such as dipropylene glycol methyl ether, methyl cellosolve (ethylene glycol monomethyl ether), cellosolve (ethylene glycol monoethyl ether), butylcarbitol (diethylene glycol monobutyl ether), etc. System solvent; Diethylene glycol monobutyl ether acetate, dipropylene glycol methyl ether acetate, butyl glycol acetate, butyl diglycol acetate, butyl cellosolve acetate, butyl carbitol acetate (diethylene glycol monobutyl ether acetate), isobornyl acetate. Ester-based solvents such as; Hydrocarbon-based solvents such as toluene, xylene, naphtha, and petroleum hydrocarbons; Mineral spirits; and organic solvents such as these.

Among them, from the viewpoint of improving the storage stability of the photosensitive composition and the handleability during forming the conductive film, an organic solvent with a boiling point of 150°C or higher, and even an organic solvent with a boiling point of 170°C or higher, is preferable. Additionally, as another suitable example, from the viewpoint of suppressing the drying temperature after printing the conductive film low, an organic solvent with a boiling point of 250°C or lower is preferable, and further, an organic solvent with a boiling point of 220°C or lower is preferable. This makes it possible to reduce production costs while improving productivity.

Suitable commercially available organic solvents include, for example, Dowanol DPM (trademark) (boiling point: 190°C, manufactured by Dow Chemical Company), Dowanol DPMA (trademark) (boiling point: 209°C, manufactured by Dow Chemical Company) product), mentanol (boiling point: 207°C), mentanol P (boiling point: 216°C), Isopar H (boiling point: 176°C, manufactured by Kantonenryo Co., Ltd.), SW-1800 (boiling point: 198°C, Maruzen Sekiyu) Co., Ltd.), etc. may be mentioned.

When the photosensitive composition contains an organic dispersion medium, there is no particular limitation, but the proportion of the organic dispersion medium in the entire photosensitive composition is generally 1 to 50% by mass, typically 3 to 30% by mass, for example 5 to 20% by mass. It can be %.

＜Other added ingredients＞

The photosensitive composition may contain various additional components as needed in addition to the components described above, as long as they do not significantly impair the effect of the technology disclosed herein. As the additive component, one or two or more types can be appropriately selected and used from among those known in the art. Examples of added ingredients include, for example, inorganic fillers, photosensitizers, polymerization inhibitors, radical scavengers, antioxidants, ultraviolet absorbers, plasticizers, surfactants, leveling agents, thickeners, anti-foaming agents, anti-gelling agents, stabilizers, and preservatives. , pigments, etc. Although not particularly limited, the proportion of added components in the entire photosensitive composition may be generally 5% by mass or less, typically 3% by mass or less, for example, 2% by mass or less, and preferably 1% by mass or less.

As described above, the photosensitive composition disclosed herein contains a dispersant with a high solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more. This allows the unexposed portion to be quickly and appropriately removed in the development process. As a result, the development time can be shortened and the generation of residues between lines can be reduced.

In other words, space can be stably secured between adjacent wirings. Therefore, even if it is a fine-line conductive layer with a small L/S, it can be formed with good reproducibility, thereby improving productivity and yield.

＜Use of photosensitive composition＞

According to the photosensitive composition disclosed herein, a fine line conductive layer can be stably formed. Therefore, the photosensitive composition disclosed herein can be suitably used for forming conductive layers in various electronic components such as inductance components, condenser components, and multilayer circuit boards, for example.

Electronic components may be of various mounting types, such as surface mounting type or through-hole mounting type. Electronic components may be of a laminated type, a wound type, or a thin film type. Typical examples of inductance components include high-frequency filters, common-mode filters, inductors (coils) for high-frequency circuits, inductors (coils) for general circuits, high-frequency filters, choke coils, and transformers.

Ceramic electronic components are an example of electronic components. In addition, in this specification, “ceramic electronic components” refers to all electronic components made using ceramic materials, and includes electronic components having an amorphous ceramic substrate (glass ceramic substrate) or a crystalline (i.e. non-glass) ceramic substrate. Includes the first half. Typical examples of ceramic electronic components include a high-frequency filter with a ceramic substrate, a ceramic inductor (coil), a ceramic condenser, a low-temperature fired multilayer ceramic substrate (Low Temperature Co-fired Ceramics Substrate: LTCC substrate), and a high-temperature fired multilayer ceramic substrate (High Temperature Co-fired Ceramic Substrate). Co-fired Ceramics Substrate: HTCC (based on HTCC), etc. may be mentioned.

Ceramic materials are not particularly limited, but include, for example, zirconium oxide (zirconia), magnesium oxide (magnesia), aluminum oxide (alumina), silicon oxide (silica), titanium oxide (titania), and cerium oxide (ceria). ), oxide-based materials such as yttrium oxide (yttria), and barium titanate; complex oxide-based materials such as coredierite, mullite, forsterite, steatite, sialon, zircon, and ferrite; silicon nitride (silicon nitride) ), nitride-based materials such as aluminum nitride (alumina nitride); carbide-based materials such as silicon carbide (silicon carbide); hydroxide-based materials such as hydroxyapatite; and the like.

Figure 1 is a cross-sectional view schematically showing the structure of the multilayer chip inductor 1. Additionally, the dimensional relationships (length, width, thickness, etc.) in FIG. 1 do not necessarily reflect actual dimensional relationships. In addition, symbols However, this is only for convenience of explanation.

The multilayer chip inductor 1 includes a main body 10 and external electrodes 20 provided on both side surfaces of the main body 10 in the left and right direction X. The multilayer chip inductor 1 has a size of, for example, 1608 shape (1.6 mm x 0.8 mm), 2520 shape (2.5 mm x 2.0 mm), etc.

The main body 10 has a structure in which a ceramic layer (dielectric layer) 12 and an internal electrode layer 14 are integrated. The ceramic layer 12 is made of ceramic material. An internal electrode layer 14 is disposed between the ceramic layers 12 in the vertical direction Y. The internal electrode layer 14 is formed using the photosensitive composition described above. The internal electrode layers 14 adjacent to each other in the vertical direction Y with the ceramic layer 12 interposed therebetween are electrically connected through the via 16 provided in the ceramic layer 12. As a result, the internal electrode layer 14 is configured in a three-dimensional vortex shape (spiral shape). Both ends of the internal electrode layer 14 are respectively connected to the external electrode 20.

Such a multilayer chip inductor 1 can be manufactured, for example, by the following procedure.

That is, first, a paste containing raw ceramic materials, a binder resin, and an organic solvent is prepared, and this is supplied on a carrier sheet to form a ceramic green sheet. Next, this ceramic green sheet is rolled and cut to a desired size to obtain green sheets for forming a plurality of ceramic layers. Next, via holes are formed appropriately at predetermined positions on the plurality of green sheets for forming ceramic layers using a puncher or the like.

Next, using the above-described photosensitive composition, a conductive film with a predetermined coil pattern is formed at a predetermined position on a plurality of green sheets for forming a ceramic layer. As an example, the following process: (Step S1: Forming process of film-like body) A process of forming a conductive film made of a dried body of the photosensitive composition by applying the photosensitive composition onto a green sheet for forming a ceramic layer and drying it; (Step S2: Exposure process) A process of covering a conductive film with a photomask with a predetermined opening pattern, exposing it to light through the photomask, and partially photocuring the conductive film; (Step S3: Development process) A process of etching the conductive film after photocuring and removing the unexposed portion; A conductive film in an unbaked state can be formed by a manufacturing method including.

Additionally, when forming a conductive film using the photosensitive composition, conventionally known methods can be appropriately used. For example, in (Step S1), application of the photosensitive composition can be performed using various printing methods such as screen printing, a bar coater, etc. Drying of the photosensitive composition may be performed at a temperature below the boiling point of the photopolymerizable compound and the photopolymerization initiator, typically 50 to 100°C. In (Step S2), for exposure, an exposure machine that emits light in a wavelength range of 10 to 500 nm, for example, an ultraviolet ray irradiation lamp such as a high-pressure mercury lamp, a metal halide lamp, or a xenon lamp, can be used. In (Step S3), an alkaline aqueous developer can typically be used for etching. For example, an aqueous solution containing sodium hydroxide, sodium carbonate, etc. can be used. The concentration of the alkaline aqueous solution may be adjusted to, for example, 0.01 to 0.5% by mass.

Next, (step S4: firing process), a plurality of green sheets for forming a ceramic layer on which an unsintered conductive film is formed are stacked and pressed. In this way, a laminate of unfired ceramic green sheets is produced. Next, the laminate of ceramic green sheets is fired at, for example, 600 to 1000°C. As a result, the ceramic green sheets are integrally sintered to form the main body 10 including the ceramic layer 12 and the internal electrode layer 14 made of a sintered photosensitive composition. Then, an appropriate external electrode forming paste is applied to both ends of the main body 10 and fired, thereby forming the external electrode 20. As described above, the multilayer chip inductor 1 can be manufactured.

Hereinafter, several embodiments of the present invention will be described, but it is not intended to limit the present invention to the related embodiments.

(Preparation of dispersant)

First, eight types of commercially available dispersants (dispersants a to h) shown below were prepared.

(Dispersant a): Marialim (trademark) SC1015F, manufactured by Daicel Allnex Co., Ltd., a polycarboxylic acid-based polymer ionic dispersant having a polyoxyalkylene chain on the side chain and a weight average molecular weight of 20,000 to 3. only

(Dispersant b): Hypermer (trademark) KD-2, manufactured by Kuroda Japan Co., Ltd., a polyamine-based polymer ionic dispersant having polyamine as its main skeleton and a polyoxyalkylene chain as a side chain, weight average molecular weight 2000

(Dispersant c): Hypermer (trademark) KD-9 manufactured by Kuroda Japan Co., Ltd., a polycarboxylic acid-based polymer ionic dispersant with a hydrocarbon chain as a side chain, weight average molecular weight 760, acid value 74 mgKOH/g.

(Dispersant d): Hypermer (trademark) KD-21 manufactured by Kuroda Japan Co., Ltd., amphoteric ionic dispersant containing an amide bond and a carboxyl group.

(Dispersant e): Hypermer (trademark) KD-3 manufactured by Kuroda Japan Co., Ltd., a polyamine-based polymer ionic dispersant with a main skeleton and a hydrocarbon chain on the side chain.

(Dispersant f): Hypermer (trademark) LP5 manufactured by Kuroda Japan Co., Ltd., a polyamine-based polymer ionic dispersant with a main skeleton and a hydrocarbon chain on the side chain.

(Dispersant g): Hypermer (trademark) KD-15, manufactured by Kuroda Japan Co., Ltd., a linear ionic dispersant with oleic acid as the main chain and a dicarboxylic acid at one end of the main chain.

(Dispersant h): Crodafos (trademark) O3A, manufactured by Kuroda Japan Co., Ltd., phosphoric acid-based dispersant

(Measurement of SP value of dispersant)

For each dispersant, SP value was calculated by turbidity titration method. Specifically, in an environment of 25°C, first, 0.3 g of the dispersant was weighed in a beaker, and 11.3 ml of acetone (a good solvent) with an SP value of 9.8 (cal/cm ³ ) ^1/2 was added thereto to sufficiently dissolve the dispersant. dissolved. There, as a poor solvent with a low SP value, n-hexane with a SP value (δml) of 7.2 (cal/cm ³ ) ^1/2 was added dropwise little by little, and the drop amount Vml (ml) at the point where white turbidity occurred was recorded. Likewise, as a poor solvent with a high SP value, pure water with a SP value (δmh) of 23.4 (cal/cm ³ ) ^1/2 was added dropwise little by little, and the drop amount Vmh (ml) at the point where white turbidity occurred was recorded. The results are shown in Table 1 below.

Then, the SP values δml and δmh of the poor solvent and the dropping amounts Vml and Vmh shown in Table 1 were applied to the following equation (1) to calculate the SP value (δ). The results are shown in Tables 1 and 2. As shown in Tables 1 and 2, the SP values of dispersants a to d alone are 9.9 (cal/cm ³ ) ^1/2 or more, and the SP values of dispersants e to h alone are 9.9 (cal/cm 3 ) 1/2 or more. cm ³ ) was less than ^1/2 .

(However, V _ml is the volume of a poor solvent with a low SP value, V _mh is the volume of a poor solvent with a high SP value, δ _ml is the SP value of a poor solvent with a low SP value, and δ _mh is, This is the SP value of a poor solvent with a high SP value.)

(Preparation of photosensitive composition)

First, silver powder (D ₅₀ particle size: 2 μm) was prepared as a noble metal powder. In addition, as a photopolymerizable compound, an acrylic polymer (Cychromer P (trademark) ACA Z320 manufactured by Daicel Allnex Co., Ltd., weight average molecular weight: 23000, double bond equivalent: 450, resin acid value: 130 mgKOH/g, Tg value: 140°C ), and urethane acrylate monomer were prepared.

And, the silver powder prepared above, an acrylic polymer, a urethane acrylate monomer, a cellulose-based polymer compound as an organic binder, a photosensitizer, a photopolymerization initiator (IRGACURE (trademark) 369 manufactured by BASF Japan Co., Ltd.), and others. The added components (here, an anti-gelling agent, a polymerization inhibitor, and an ultraviolet absorber were used) were weighed so that the content ratios were as shown in Table 2, dissolved in an organic dispersion medium, and additionally, dispersants a to h were added appropriately to achieve photosensitivity. Compositions (Examples 1 to 9, Comparative Examples 1 to 7) were prepared. In addition, the mass ratio shown in Table 2 is the content ratio (mass parts) when silver powder is 100 parts by mass.

(Production of wiring pattern)

First, the photosensitive composition prepared above was applied to commercially available ceramic green sheets with a size of □ 4 cm x 4 cm, respectively, by screen printing. Next, this was dried at 60°C for 15 minutes, and a conductive film (beta film) was formed on the green sheet (film-like body forming process). Next, a photomask was applied from above the conductive film. At this time, the photomask used was a pattern in which the line width of the wiring was 20 μm and the space between adjacent lines was 20 μm (L/S = 20 μm/20 μm). With this photomask covered over the conductive film, light was irradiated using an exposure machine under the conditions of an illumination intensity of 9 mJ/cm ² and an exposure amount of 1800 mJ/cm ² to cure the exposed portion (exposure process). After exposure, a 0.1% by mass alkaline Na ₂ CO ₃ aqueous solution (developer) was sprayed on the surface of the ceramic green sheet until the break point (BP) was reached (development process). In addition, BP was set as the time until the unexposed part was developed with an alkaline developer of 0.1% by mass and it could be visually confirmed that the unexposed part had disappeared. After removing the unexposed portion in this way, it was washed with pure water and dried at room temperature. In this way, a conductive film (dry film) of a wiring pattern was formed on the ceramic green sheet.

(Evaluation of wiring pattern)

The wiring pattern produced above was evaluated for developability, presence or absence of residue, and tackiness.

·Evaluation of developability:

In the development process, the time until the break point (B.P.) was reached (development time) was measured. The results are shown in the column “Development time (seconds)” in Table 2. In addition, using the development time of Comparative Example 1 (a test example in which no dispersant was added) as a standard, the difference in development time from Comparative Example 1 was calculated for each test example. The results are shown in the column “Difference from Comparative Example 1 (seconds)” in Table 2. In addition, based on the difference in development time from Comparative Example 1, developability was evaluated with the following index.

“◎”: Development time is shorter than Comparative Example 1 by 5 seconds or more (good developability).

“×”: The development time is equivalent to or slower than Comparative Example 1 (poor developability).

·Evaluation of presence or absence of residue:

The space portion of the wiring pattern was observed with an optical microscope for a total of 10 views, and the presence or absence of residues was confirmed from the obtained observation images. The results are shown in the column “Presence or absence of residue” in Table 2. The notation in the relevant column is as follows.

「◎」: Out of 10 fields of view, the residue is less than 1 field of view.

「○」: Out of 10 visual fields, the residue is in 2 to 4 visual fields.

“×”: Out of 10 visual fields, the residue is 5 or more visual fields.

·Text evaluation:

A polyethylene terephthalate (PET) film was placed on the formed conductive film, and pressed from above with a load of 2 kg for 24 hours. Then, the adhesion of the conductive film when the PET film was peeled off 24 hours later was evaluated. The results are shown in the “Textability” column of Table 2. The notation for the relevant column is as follows.

“◎”: The conductive film did not adhere to the PET film (no peeling).

“×”: The conductive film adhered to the PET film (there was peeling).

Comparative Example 1 is a test example in which no dispersant was added. As shown in Table 2, in Comparative Example 1, the development time was relatively long, and many residues were confirmed in the space portion. In addition, in Comparative Examples 3 to 7 using a dispersant with an SP value of 9.46 or less, the development time was long as in Comparative Example 1, and many residues were also confirmed in the space portion. Additionally, in Comparative Example 2 using a dispersant with an SP value of 9.80, the development time was shorter than Comparative Example 1, but many residues were still observed in the space portion.

Compared to Comparative Examples 1 to 7, in Examples 1 to 9, which used a dispersant with an SP value of 9.9 (cal/cm ³ ) ^1/2 or more, the development time was shorter than that of Comparative Example 1, and the generation of residues was also suppressed to a low level. It was done. In other words, by using a dispersant with an SP value of 9.9 or more, the effects of the technology disclosed herein were fully exhibited, for example, regardless of the structure of the dispersant. Among them, in Examples 1 to 8, which did not contain a compound with an SP value of less than 9.9, the generation of residues was better suppressed. In addition, from the comparison of Examples 1 to 5 in which the addition amount of the dispersant was different, by setting the content ratio of the dispersant to 100 parts by mass of silver powder to 0.1 to 2.7 parts by mass, the removal of the unexposed portion in the developing process was improved while the exposed portion was removed. Adhesion (tackiness) to the substrate was improved. These results demonstrate the significance of the technology disclosed herein.

Although the present invention has been described in detail above, these are merely examples, and various changes can be made to the present invention without departing from its main scope.

1 stacked chip inductor
10 Main body
12 Ceramic layer
14 Internal electrode layer
20 external electrode

Claims (10)

Contains precious metal powder, a photopolymerizable compound, a photopolymerization initiator, and a dispersant,
The dispersant is a first compound having a weight average molecular weight of 100 or more and 100,000 or less, a linear linear structure or a branch-shaped structure with a plurality of side chains arranged along a linear main skeleton, and having an ionic functional group, and It contains at least one of the second compounds having a weight average molecular weight of 100 to 100,000 and having at least one acidic group,
The solubility parameter of the dispersant (however, when using multiple types of compounds as the dispersant, it refers to the sum (weighted average value) of the product of the solubility parameter of each compound and the composition ratio of each compound) is 9.9 (cal/ cm ³ ) photosensitive composition of at least ^1/2 . In claim 1,
A photosensitive composition wherein the photopolymerizable compound includes a photopolymerizable polymer with a weight average molecular weight of 5000 or more. In claim 1 or claim 2,
A photosensitive composition wherein the photopolymerizable compound contains one or two or more compounds having an acidic group. In claim 1 or claim 2,
A photosensitive composition wherein the content of the dispersing agent is 0.1 part by mass or more and 2.7 parts by mass or less when the total of the noble metal powder is 100 parts by mass. In claim 1 or claim 2,
A photosensitive composition in which the dispersant consists only of compounds having a solubility parameter of 9.9 (cal/cm ³ ) ^1/2 or more. In claim 1 or claim 2,
A photosensitive composition wherein the dispersing agent contains at least the second compound. In claim 1 or claim 2,
A photosensitive composition in which the noble metal powder contains silver-based particles. green sheet,
A composite disposed on the green sheet and comprising a conductive film made of the dried photosensitive composition of claim 1 or 2. An electronic component comprising a conductive layer made of a sintered body of the photosensitive composition of claim 1 or 2. A method of manufacturing an electronic component comprising the step of applying the photosensitive composition of claim 1 or 2 on a substrate, exposing and developing it, and then baking it to form a conductive layer made of a sintered body of the photosensitive composition.