WO2021005910A1 - Photosensitive composition production method, pasty photosensitive composition, electronic component production method, electronic component, device for determining mixing ratio for organic component in photosensitive composition, and computer program - Google Patents

Abstract

The present invention provides a photosensitive composition production method comprising: the step of measuring the particle size of a conductive powder to be used to obtain an actually measured value (step S1); the step of comparing the actually measured value with a first correlation formula, which represents the correlation between particles size for the conductive powder and any factor among factors that change in correlation with change in particle size, to identify a predicted offset value for the factor relative to a pre-determined target level (step S2); and the step of determining a mixing ratio for an organic component to cancel out the predicted offset value on the basis of a second correlation formula, which represents the correlation between the factor in the first correlation formula and said organic component, said organic component being any of the organic components included in the photosensitive composition and for which changes in the mixing ratio are correlated with changes in the factor (step S3).

Description

A method for producing a photosensitive composition, a paste-like photosensitive composition, a method for producing an electronic component and an electronic component, and a device for determining a blending ratio of organic components in the photosensitive composition, a computer program.

The present invention relates to a method for producing a photosensitive composition, a paste-like photosensitive composition, a method for producing an electronic component and an electronic component, a compounding ratio determining device for an organic component in the photosensitive composition, and a computer program.
It should be noted that this application claims priority based on Japanese Patent Application No. 2019-128628 filed on July 10, 2019, and the entire contents of the application are incorporated herein by reference. There is.

In the manufacture of electronic components such as inductors, a method of forming a conductive layer on a substrate by a photolithography method using a photosensitive composition containing a conductive powder, a photopolymerizable resin, and a photopolymerization initiator is known. (See, for example, Patent Documents 1 and 2). In such a method, first, a photosensitive composition is applied onto a base material and dried to form a conductive film (a conductive film forming step). Next, the molded conductive film is covered with a photomask having a predetermined aperture pattern, and the conductive film is exposed through the photomask (exposure step). As a result, the exposed portion of the conductive film is photocured. Next, the unexposed portion that has been shielded from light by the photomask is corroded with a developing solution and removed (development step). Then, the conductive film having a desired pattern is fired to be baked onto the base material (firing step). According to the photolithography method including the above steps, a finer conductive layer can be formed as compared with various conventional printing methods.

Japanese Patent No. 5163687 International Publication 2015/12234

By the way, in recent years, various electronic devices have been rapidly miniaturized and improved in performance, and electronic components mounted on electronic devices are also required to be further miniaturized and have a higher density. Along with this, in the manufacture of electronic components such as multilayer chip inductors, it is required to reduce the resistance of the conductive layer and to make the wires thinner (narrower). More specifically, the line width of the wiring constituting the conductive layer and the space (line and space: L / S) between the adjacent wirings are reduced to 30 μm / 30 μm or less, and further to 20 μm / 20 μm or less. Is required. If the L / S of the conductive layer is small, even if the line width of the wiring is slightly thickened, adjacent wires will be connected to each other to cause a short circuit defect, or conversely, if the line width of the wiring is slightly narrowed, it will be peeled off. Or disconnection is likely to occur. Therefore, for electronic components such as multilayer chip inductors, if the line width varies widely, the product characteristics may be adversely affected or the yield may decrease. Therefore, from the viewpoint of mass production, by suppressing the variation in the line width of the conductive film after development to a low level, the variation in the line width of the conductive layer after firing is suppressed, and fine linear wiring in electronic components is formed with good reproducibility. It is necessary to do.

The present invention has been made in view of this point, and an object of the present invention is to provide a photosensitive composition capable of forming fine line-shaped wiring with a desired line width with good reproducibility. Another related purpose is to provide a method of manufacturing electronic components and electronic components. Another related object is to provide a compounding ratio determining device and a computer program for organic components in a photosensitive composition.

As a result of diligent studies on each component of the photosensitive composition, the present inventors have newly found that the particle size of the conductive powder is one important factor for determining the line width after development. did. That is, FIG. 1A is a schematic side view showing the state of the exposure process when the conductive powder 1A having a relatively large particle size is used. As shown in FIG. 1A, when the particle size of the conductive powder 1A is large, the light that has entered the inside of the conductive film through the opening of the photomask is reflected on the surface of the conductive powder 1A and is easily scattered. Therefore, the light tends to spread in the horizontal direction of the conductive film. As a result, the light reaches the periphery of the opening of the photomask (the portion shaded by the photomask), and the line width tends to be wider than the width of the opening of the photomask. On the other hand, FIG. 1B is a schematic side view showing a state of the exposure process when the conductive powder 1B having a relatively small particle size is used. As shown in FIG. 1B, when the particle size of the conductive powder 1B is small, the light that has entered the inside of the conductive film through the opening of the photomask is not easily reflected on the surface of the conductive powder 1B, and the light is scattered. It can be suppressed. Therefore, it is difficult for light to spread in the horizontal direction of the conductive film, and the line width tends to be relatively narrower than that in FIG. 1A. From this, it can be said that it is desirable to highly control the particle size of the conductive powder used in order to stabilize the line width.

However, according to the investigation by the present inventors, the particle size of the conductive powder varies to some extent depending on the production lot (product unit). For example, when the present inventors purchased conductive powders of several production lots having an average particle size (nominal value) of 2.9 μm and actually measured the average particle size, the average particle size (measured value) was the nominal value. It fluctuated by about ± 0.4 μm. This fluctuation is considered to be due to variations in the manufacturing process. Therefore, it was expected that the line width would vary due to fluctuations in the average particle size (measured value) of the conductive powder as it is. Therefore, the present inventors wondered if the variation in line width caused by the variation between production lots of the conductive powder could be buffered during the production of the photosensitive composition. As a result of further studies, the present invention has been created.

INDUSTRIAL APPLICABILITY The present invention provides a method for producing a photosensitive composition containing a conductive powder at a predetermined compounding ratio. This manufacturing method is a step of measuring the particle size of the conductive powder to be used to obtain an actually measured value; the above measured value is a first correlation formula prepared in advance, and the particle size of the conductive powder and the above measured value are used. A predetermined target level in comparison with the first correlation equation with any factor that fluctuates due to light absorption or photocuring of the conductive film and fluctuates in correlation with the displacement of the particle size. Step of confirming the expected deviation value of the above-mentioned factors with respect to the above; a second correlation equation prepared in advance, in which the factors in the first correlation equation and the organic components contained in the photosensitive composition are varied in the compounding ratio. Includes the step of determining the blending ratio of the organic component so as to cancel the expected deviation value based on the second correlation equation with any organic component that correlates with the variation of the factor.

In the above manufacturing method, the particle size of the conductive powder used for manufacturing the photosensitive composition is measured in advance, and the expected deviation value with respect to the target level is simulated. Then, based on the result of the simulation, the blending ratio of the organic component is determined so as to cancel the expected deviation value. As a result, the influence of fluctuations between the production lots of the conductive powder is reduced, and the variation in line width caused by the difference in the production lots of the conductive powder can be suppressed. Therefore, it is not necessary to control the particle size of the conductive powder so highly, and even if the production lot of the conductive powder to be purchased is switched in the middle, the desired line width can be stably formed. The composition can be provided. As a result, the yield can be improved and mass productivity and productivity can be improved.

In a preferred embodiment disclosed herein, the organic component is an organic component that adjusts at least one of the light absorption and photopolymerizability of the photosensitive composition. The organic component may be at least one of a photopolymerization initiator system, a light absorber, and a polymerization inhibitor. The organic component may be a photopolymerization initiator system. This makes it possible to stabilize the blending ratio of, for example, a photocurable component (a component that cures by polymerization reaction, for example, a photocurable compound) in a photosensitive composition, and has various properties of a conductive film, for example, with respect to a substrate. The effects of the techniques disclosed herein can be achieved while maintaining high tackiness as a whole.

In a preferred embodiment disclosed here, the factors in the first correlation equation are the line width, film thickness, electrode cross-sectional area, curing shrinkage rate, or resistance value of the conductive film. The factor in the first correlation equation may be a line width.

In a preferred embodiment disclosed here, the second correlation equation is represented by a linear function. Since the two variables are in a proportional relationship in the linear function, the compounding ratio can be calculated simply and easily.

In a preferred embodiment disclosed herein, the conductive powder comprises silver-based particles. As a result, it is possible to realize a conductive layer having an excellent balance between cost and low resistance.

In a preferred embodiment disclosed here, the first conductive powder is a core-shell particle containing a metal material as a core and a ceramic material covering at least a part of the surface of the core. As a result, the stability of the conductive powder in the photosensitive composition can be improved better, and a highly durable conductive layer can be realized. Further, for example, in an application in which a conductive layer is formed on a ceramic base material (ceramic base material) to manufacture a ceramic electronic component, the integrity with the ceramic base material can be enhanced.

Further, according to the present invention, a step of applying the photosensitive composition onto a substrate, performing photocuring and etching, and then firing to form a conductive layer made of a fired body of the photosensitive composition. Methods for manufacturing electronic components are provided, including. According to such a manufacturing method, an electronic component having a small and / or high-density conductive layer can be suitably manufactured.

Further, the present invention provides a blending ratio determining device for determining a blending ratio of an organic component with respect to a photosensitive composition containing a conductive powder at a predetermined blending ratio. This compounding ratio determining device is a first correlation equation prepared in advance with an input unit in which the type of conductive powder to be used and the measured value of the particle size are input in response to the input of the user. The first correlation equation between the particle size of the conductive powder and any factor that fluctuates due to light absorption or photocuring of the conductive film and that fluctuates in correlation with the displacement of the particle size, and A second correlation equation prepared in advance, one of the factors in the first correlation equation and any of the organic components contained in the photosensitive composition in which the fluctuation of the compounding ratio correlates with the fluctuation of the factor. A storage unit that stores the second correlation equation with the component, and a factor in the first correlation equation with respect to a predetermined target level from the actually measured value input to the input unit based on the first correlation equation. Includes a first calculation unit for calculating the expected deviation value and a second calculation unit for calculating the compounding ratio of the organic component in the second correlation equation that cancels the expected deviation value based on the second correlation equation. .. As a result, calculation errors can be prevented, and even an operator who is not proficient in the work can easily determine the blending ratio of the organic component.

Further, the present invention provides a computer program configured to operate a computer as the above-mentioned compounding ratio determining device. As a result, calculation errors can be prevented, and even an operator who is not proficient in the work can easily determine the blending ratio of the organic component.

Further, according to the present invention, an electronic component including a conductive layer made of a fired body of the above photosensitive composition is provided. According to the above-mentioned photosensitive composition, even a conductive layer provided with fine wire-shaped wiring can be stably realized. Therefore, according to the above-mentioned photosensitive composition, it is possible to preferably realize an electronic component having a small size and / or a high-density conductive layer.

Further, according to the present invention, there is provided a paste-like photosensitive composition in which the above-mentioned photosensitive composition contains an organic dispersion medium. By preparing the paste, the photosensitive composition can be easily supplied to a desired position of the base material in a desired form by means such as coating or printing.

1A and 1B are schematic side views of a conductive film. FIG. 1A shows a case where a conductive powder having a large average particle size is used, and FIG. 1B shows a case where a conductive powder having a large average particle size is used. It is a side view of. FIG. 2 is a flowchart of a manufacturing method according to an embodiment of the present invention. FIG. 3 is a cross-sectional view schematically showing the structure of the laminated chip inductor. FIG. 4 is a functional block diagram of the compounding ratio determining device. FIG. 5 is an example of the first correlation equation according to the first embodiment. FIG. 6 is an example of the second correlation equation relating to the photopolymerization initiator system. FIG. 7 is a graph comparing the solid line widths. FIG. 8 is an example of the first correlation equation according to the second embodiment. FIG. 9 is an example of the first correlation equation according to the second embodiment. FIG. 10 is an example of the second correlation equation relating to the ultraviolet absorber. FIG. 11 is an example of the second correlation equation relating to the photopolymerization inhibitor.

Hereinafter, preferred embodiments of the present invention will be described. It should be noted that matters other than those specifically mentioned in the present specification and necessary for carrying out the present invention (for example, a method for forming a conductive film or a conductive layer, a method for manufacturing an electronic component, etc.) are described in the present specification. It can be understood based on the technical content taught by the above and the general technical common sense of those skilled in the art in the field. The present invention can be carried out based on the contents disclosed in the present specification and common general technical knowledge in the art.

In the present specification, the "conductive film" refers to a film-like body (dried product) obtained by drying a photosensitive composition at a temperature equal to or lower than the boiling point of an organic component (generally 200 ° C. or lower, for example 100 ° C. or lower). The conductive film includes all unfired (before firing) film-like bodies. The conductive film may be an uncured product before photo-curing or a cured product after photo-curing. Further, in the present specification, the “conductive layer” refers to a sintered body (fired product) obtained by firing a photosensitive composition at a temperature equal to or higher than the sintering temperature of a conductive powder. The conductive layer includes wiring (linear body), wiring pattern, and solid pattern. In addition, the notation of "A to B" indicating the range in the present specification includes the meanings of "A or more and B or less", as well as "preferably larger than A" and "preferably smaller than B".

<< Manufacturing method of photosensitive composition >>
In the present embodiment, a manufacturing method in which the target level factor is the line width (targeting the line width) will be described from the background that the line width is particularly important as a required characteristic. That is, in the present embodiment, the predetermined target level is represented by the "target line width", and the expected deviation value is represented by the "expected deviation width". However, as will be described later, the target level factor may be due to the light absorption degree or the photocurability degree of the conductive film, and is not limited to the line width.

FIG. 2 is a flowchart of the manufacturing method according to the present embodiment. The production method disclosed herein is a method for producing a photosensitive composition containing a conductive powder at a predetermined compounding ratio. In the present embodiment, such a production method is described in the following steps: (step S1) measurement step of average particle size; (step S2) confirmation step of expected deviation width; (step S3) step of determining compounding ratio of organic components; (step S3). S4) The step of preparing the photosensitive composition; Hereinafter, each step will be described in order.

<(Step S1) Measurement step of average particle size>
In this step, first, a conductive powder used for producing a photosensitive composition is prepared. The conductive powder is a component that imparts electrical conductivity to the conductive layer. The conductive powder may be purchased as a commercially available product, or may be produced by itself by a conventionally known method. The type of the conductive powder is not particularly limited, and one of the conventionally known ones may be used alone or two or more of them may be appropriately combined depending on the intended use.

Examples of the conductive powder include gold (Au), silver (Ag), copper (Cu), platinum (Pt), palladium (Pd), aluminum (Al), nickel (Ni), ruthenium (Ru), and rhodium ( Examples thereof include simple metals such as Rh), tungsten (W), iridium (Ir), and osmium (Os), and 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 a preferred embodiment, the conductive powder comprises silver-based particles. Silver is relatively inexpensive and has high electrical conductivity. Therefore, since the conductive powder contains silver-based particles, it is possible to realize a conductive layer having an excellent balance between cost and low resistance. In addition, in this specification, "silver-based particles" include all those containing a silver component. Examples of silver-based particles include silver alone, the above-mentioned silver alloy, and core-shell particles having silver-based particles as a core, for example, silver-ceramic core-shell particles and the like.

An organic surface treatment agent may be attached to the surface of the conductive powder. The organic surface treatment agent, for example, improves the dispersibility of the conductive powder in the photosensitive composition, enhances the affinity between the conductive powder and other contained components, and surface oxidizes the metal constituting the conductive powder. It can be used for at least one of the purposes of preventing. Examples of the organic surface treatment agent include fatty acids such as carboxylic acids and benzotriazole compounds.

In a preferred embodiment, the conductive powder contains metal-ceramic core-shell particles. Metal-ceramic core-shell particles have a core containing a metal material and a coating containing a ceramic material and covering at least a portion of the surface of the core. The coating is typically composed of a plurality of fine ceramic particles. The average particle size of the ceramic particles constituting the coating portion is typically smaller than the average particle size of the metal material constituting the core portion, for example, 1/1000 to 1/2 of the average particle size of the metal material, and further. It may be about 1/100 to 1/10. Ceramic materials are excellent in chemical stability, heat resistance, and durability. Therefore, by adopting the form of metal-ceramic core-shell particles, it is possible to better improve the stability of the conductive powder in the photosensitive composition and realize a highly durable conductive layer. Further, for example, in an application in which a conductive layer is formed on a ceramic base material to manufacture a ceramic electronic component, the integralness with the ceramic base material can be enhanced, and the conductive layer can be preferably peeled off or broken after firing. It can be suppressed.

Although not particularly limited, examples of the ceramic material constituting the coating portion of the core-shell particles include zirconium oxide (zirconia), magnesium oxide (magnesia), aluminum oxide (alumina), silicon oxide (silica), and titanium oxide. (Titania), cerium oxide (ceria), ittium oxide (itria), barium titanate and other oxide-based materials; cordierite, mulite, forsterite, steatite, sialon, zircone, ferrite and other composite oxide-based materials Nitride-based materials such as silicon nitride (silicon nitride) and aluminum nitride (aluminum nitride); carbide-based materials such as silicon carbide (silicon carbide); hydroxide-based materials such as hydroxyapatite; and the like. For example, in an application in which a conductive layer is formed on a ceramic base material to manufacture a ceramic electronic component, a ceramic material having the same or excellent affinity as the ceramic base material is preferable. Although not particularly limited, the content ratio of the ceramic material in the core-shell particles may be, for example, 0.01 to 5.0 parts by mass with respect to 100 parts by mass of the metal material in the core portion.

Although not particularly limited, when a commercially available conductive powder is used, the average particle size (nominal value) of the conductive powder is determined in consideration of the exposure performance (for example, light absorption and photocurability). It may be approximately 0.1 to 10 μm. By setting the average particle size (nominal value) in the above range, fine wire-shaped wiring can be formed more stably. From the viewpoint of suppressing aggregation in the photosensitive composition and improving the storage stability of the photosensitive composition, the average particle size of the conductive powder (nominal value, for example, measurement of laser diffraction / scattering method or SEM observation) , Etc.) may be, for example, 0.5 μm or more, 1 μm or more, 1.5 μm or more, and 2 μm or more. Further, from the viewpoint of improving the fine line forming property, densifying the conductive layer, and reducing the resistance, the average particle size (nominal value) of the conductive powder is, for example, 5 μm or less, 4.5 μm or less. It may be 4 μm or less.

Although not particularly limited, the conductive powder is typically a substantially spherical shape having an average aspect ratio of about 1 to 2, preferably 1 to 1.5, for example, 1 to 1.3. As a result, the exposure performance can be realized more stably. In the present specification, the "average aspect ratio" is an arithmetic mean value (major axis / major axis / major axis) of the aspect ratio calculated from an observation image obtained by observing a plurality of conductive particles constituting the conductive powder with an electron microscope. Minority ratio). Further, in the present specification, the term "spherical" means a form that can be generally regarded as a sphere (ball) as a whole, and may include an elliptical shape, a polygonal shape, a disk spherical shape, and the like.

Although not particularly limited, the conductive powder is preferably having a lightness L ^* of 50 or more in the L ^* a ^* b ^* color system based on JIS Z 8781: 2013. As a result, the light can reach the deep part of the uncured conductive film stably at the time of exposure, and for example, a thick conductive layer having a film thickness of 5 μm or more and further 10 μm or more is stably formed. can do. From the above viewpoint, the lightness L ^* of the conductive powder may be approximately 55 or more, for example 60 or more. The brightness L ^* can be measured by, for example, a spectrocolorimeter based on JIS Z 8722: 2009.

In this step, next, the average particle size of the conductive powder used is actually measured. The method for measuring the average particle size, the measuring device, the measuring conditions, and the analysis conditions for the measurement results may be unified with those at the time of calculating the first correlation equation described later. As a result, the prediction accuracy in the subsequent step of confirming the expected deviation width (step S2) can be improved. In one example, the particle size distribution is measured using a particle size distribution measuring device based on the laser diffraction / scattering method. For example, by using the Microtrack MT-3000II series manufactured by Microtrack Bell Co., Ltd., it is possible to measure a particle size range of approximately 0.02 to 2800 μm. By measuring the particle size distribution, a volume-based particle size distribution of the conductive powder can be obtained. Then, in the particle size distribution, the particle size (D50 particle size) corresponding to the integrated value of 50% from the side with the smaller particle size is defined as the “average particle size (actual measurement value)”. As described above, the average particle size (measured value) of the conductive powder used for producing the photosensitive composition is obtained.

<(Step S2) Confirmation process of expected deviation width>
In this step, first, the first correlation equation is prepared. The first correlation equation is prepared in advance for each type of conductive powder (for example, for each product name). In the first correlation equation, the correlation coefficient R ² is generally 0.85 or more, preferably 0.9 or more, for example 0.92 or more. The first correlation equation can be prepared, for example, as follows.

That is, first, a plurality of conductive powders having different production lots and / or average particle diameters (nominal values) are prepared. At this time, physical characteristics other than the particle size of the plurality of conductive powders, for example, the metal type, average aspect ratio, and brightness of the conductive powder that can have a comparatively large effect on the exposure performance (for example, light absorption and photocurability). By unifying the conditions (substantially the same) for L ^* etc., it is possible to remove biases other than the particle size and clearly evaluate the influence of the particle size itself. Next, the average particle diameters of the prepared plurality of conductive powders are individually measured. The average particle size can be measured by a conventionally known measuring method. For example, it can be performed using a particle size distribution measuring device based on a laser diffraction / scattering method.

Next, each photosensitive composition is prepared using a plurality of conductive powders whose average particle size has been actually measured. For example, first, a predetermined vehicle containing an organic component is prepared, and a conductive powder is dispersed therein to prepare a photosensitive composition. As a result, components other than the conductive powder and their blending ratios are unified, and a plurality of photosensitive compositions different only in the type of the conductive powder are prepared. Next, the prepared photosensitive compositions are applied onto the substrate, respectively, and photocured and etched. As a result, a thin wire-shaped wiring is formed.

Next, observe the wiring on the base material and measure the line width of the wiring from the obtained observation image. For example, a laser microscope can be used for observing the wiring. At this time, the line width is measured for a plurality of fields of view, and the arithmetic mean value is taken as the solid line width (actual line width). Then, for example, the data is plotted on a graph of "average particle size (measured value) X-solid line width Y" in which the average particle size (measured value) of the conductive powder is taken on the horizontal axis X and the solid line width is taken on the vertical axis Y. To do. From this graph, the correlation formula between the average particle size (measured value) and the solid line width is calculated. In this way, the first correlation equation is prepared.

In this step, next, the measured value obtained in step S1 is compared with the first correlation equation relating to the same type of conductive powder. Then, the expected deviation width (expected deviation width) with respect to the predetermined target line width is confirmed. For example, first, the measured value obtained in step S1 is interpolated into the correlation equation between the average particle size (measured value) and the solid line width to calculate the expected line width. Then, the difference between the expected line width and the desired target line width is calculated as the expected deviation width. The target line width can be set arbitrarily. In this way, the expected deviation width is confirmed.

<(Step S3) Step of determining the mixing ratio of organic components>
In this step, first, a second correlation equation is prepared. The second correlation equation is prepared in advance for each type of conductive powder (for example, for each product name). In the second correlation equation, the correlation coefficient R ² is generally 0.85 or more, preferably 0.9 or more, for example 0.92 or more. The second correlation equation may be represented by a linear function. In a linear function, two variables are in a proportional relationship. Therefore, the compounding ratio can be calculated simply and easily. The second correlation equation can be prepared, for example, as follows. That is, first, at least one of the organic components used in the production of the photosensitive composition is prepared. For example, at least one of the organic components contained in the vehicle used in the calculation of the first correlation equation is prepared. The organic component to be prepared may be one kind or, for example, two or more kinds.

Although not particularly limited, the organic component prepared at this time is a component that affects the curing rate of the photosensitive composition, for example, the light absorption of the photosensitive composition other than the organic binder and the photocurable compound. It is preferable to contain an organic component (curing rate adjusting agent) that adjusts at least one of photopolymerizability. The organic component to be prepared may contain, for example, at least one of (A) a photopolymerization initiator, (B) a sensitizer, (C) a light absorber, and (D) a polymerization inhibitor. Among them, it is preferable to include at least one of a polymerization initiator system, that is, (A) a photopolymerization initiator and (B) a sensitizer. The organic component to be prepared may be, for example, the first component having the highest compounding ratio in the vehicle among the components (A) to (D), or may further contain the second component having the second highest compounding ratio. ..

(A) The photopolymerization initiator is a component that is decomposed by light irradiation to generate active species such as radicals and cations to promote the polymerization reaction of the photocurable component. The photopolymerization initiator is a component that adjusts the photopolymerizability of the photosensitive composition (specifically, accelerates the polymerization reaction). As the photopolymerization initiator, one of the conventionally known ones may be used alone or two or more thereof may be appropriately combined depending on, for example, the type of photocurable component. The photopolymerization initiator may be a photoradical polymerization initiator, a photocationic polymerization initiator, or a photoanionic polymerization initiator. In particular, a photoradical polymerization initiator is preferable because it has a high reaction rate and does not require curing by heat. Typical examples are benzoin-based photopolymerization initiators, α-hydroxyacetophenone-based photopolymerization initiators, α-aminoalkylphenone-based photopolymerization initiators, benzylketal-based photopolymerization initiators, α-hydroxyacetophenone-based photopolymerization initiators, α-Aminoacetophenone-based photopolymerization initiator, acylphosphine oxide-based photopolymerization initiator, titanosen-based photopolymerization initiator, 0-acyloxime-based photopolymerization initiator, oxime ester-based photopolymerization initiator, benzophenone-based photopolymerization initiator , Acrydin-based photopolymerization initiator and the like.

(B) A sensitizer (also referred to as an accelerator, a reaction accelerator, etc.) is a component that transfers the energy obtained by absorbing light to a photo-curing component to promote the polymerization reaction of the photo-curing component. The sensitizer is a component that adjusts the photopolymerizability of the photosensitive composition (specifically, accelerates the polymerization reaction). As the sensitizer, one of the conventionally known sensitizers may be used alone or two or more thereof may be appropriately used in combination, depending on, for example, the wavelength of the light to be irradiated. Typical examples include anthracene-based sensitizers, aromatic ketone-based sensitizers, biphenyl-based sensitizers, anthraquinone-based sensitizers, and the like.

(C) A light absorber (also referred to as a colorant, an organic pigment, etc.) is a component that adjusts the light absorption of the photosensitive composition. The light absorber is a component that typically changes the color of the photosensitive composition to adjust the rate of light penetration. The light absorber may be an ultraviolet absorber that absorbs part or all of the light having an ultraviolet wavelength, or may be an infrared absorber that absorbs part or all of the light having an infrared wavelength, and is of visible light. It may be a visible light absorber (for example, a blackening agent) that absorbs a part or all of the light of a wavelength. As the light absorber, one of the conventionally known ones can be used alone or two or more of them can be used in combination, for example, depending on the wavelength range of the light to be irradiated. Typical examples are benzotriazole-based light absorbers, triazine-based light absorbers, benzophenone-based light absorbers, benzoate-based light absorbers, salicylate ester-based light absorbers, cyanoacrylate-based light absorbers, resorcinol-based light absorbers, and hindered amines. Examples include system light absorbers.

In particular, when UV absorbers are exposed to UV light, the light that has entered the inside of the conductive film is scattered through the opening of the photomask, hardening the light-shielding part of the photomask, and the line width becomes thicker than the opening width of the photomask. It has the effect of reducing the phenomenon.

As the ultraviolet absorber, one having a high absorption coefficient in the wavelength range of 250 to 520 nm is preferable, and among them, an organic dye having a high absorption coefficient in the wavelength range of 350 to 450 nm is preferable. Examples of organic dyes include azo, benzophenone, aminoketone, xanthene, quinoline, aminoketone, anthraquinone, diphenylcyanoacrylate, triazine, p-aminobenzoic acid and the like. Of these, azo-based and benzophenone-based organic dyes are preferable.

Examples of the azo-based organic dye include Sudan Blue, Sudan R, Sudan II, Sudan III, Sudan IV, Oil Orange SS, Oil Violet, Oil Yellow OB, and the like. Examples of the benzophenone-based organic dye include Ubinal (registered trademark) D-50 (2,2', 4,4'-tetrahydrooxybenzophenone) manufactured by BASF, and Ubinal (registered trademark) MS40 (2-hydroxy-4). -Methoxybenzophenone 5-sulphonic acid), ubinal (registered trademark) DS49 (2,2-dihydroxy-4,4'-dimethoxybenzophenone-5,5'-sodium dissulphonate) and the like.

(D) The polymerization inhibitor (also referred to as a banning agent, a light stabilizer, a stabilizer, a radical scavenger, an oxygen scavenger, etc.) inhibits the polymerization reaction of the photocurable component and has weather resistance of the photosensitive composition. , A component that improves at least one of heat resistance and storage stability. The polymerization inhibitor is a component that adjusts the photopolymerizability of the photosensitive composition (specifically, slows down the polymerization reaction). As the polymerization inhibitor, one of the conventionally known ones can be used alone, or two or more thereof can be used in combination as appropriate. Typical examples include hydroquinone and its derivatives, and phenol derivatives.

Next, using a predetermined conductive powder, the blending ratio of the prepared organic components is changed stepwise to prepare a plurality of photosensitive compositions. Next, as in the calculation of the first correlation equation, the prepared photosensitive compositions are applied onto the substrate, and photocuring and etching are performed. As a result, a thin wire-shaped wiring is formed. Next, the wiring on the base material is observed with a laser microscope, and the line width of the wiring is measured from the obtained observation image. At this time, the line width is measured for a plurality of fields of view, and the arithmetic mean value is taken as the solid line width (actual line width). Then, for example, the data is plotted on a graph of "organic component compounding ratio X-solid line width Y" in which the horizontal axis X is the compounding ratio of the organic components in the photosensitive composition and the vertical axis Y is the solid line width. From this graph, the correlation formula between the compounding ratio of the organic component and the solid line width is calculated. In this way, the second correlation equation is prepared.

In this step, next, the second correlation equation is used to determine the blending ratio of the organic component in the photosensitive composition so as to cancel the expected deviation width confirmed in step S2. In other words, the blending ratio of the organic component in the photosensitive composition is determined so as to induce the target line width. In one example, the formulation of the vehicle used in the calculation of the first correlation equation is used as a base. Then, for at least one of the organic components for which the second correlation equation has been calculated, the compounding ratio is changed from the base vehicle. As a result, the expected deviation width confirmed in step S2 can be cancelled. The organic component that does not change the blending ratio may be the same as the base vehicle. The blending ratio may be changed by one type. For example, when the expected deviation width is large, the blending ratio of two or more kinds of organic components is changed little by little to predict the whole. The deviation width may be canceled out.

For example, when canceling the expected deviation width by using a polymerization initiator system, first prepare a correlation equation between the compounding ratio of the polymerization initiator system and the solid line width as the second correlation equation. For example, two equations are prepared: a correlation equation between the compounding ratio of the photopolymerization initiator and the solid line width, and a correlation equation between the compounding ratio of the sensitizer and the solid line width. In this correlation equation, it is assumed that the compounding ratio of the polymerization initiator system and the solid line width have a positive correlation. In this case, if the expected line width is larger than the target line width, the compounding ratio of the polymerization initiator system is reduced from the compounding of the base vehicle so as to cancel the expected deviation width based on the correlation equation. On the other hand, if the expected line width is smaller than the target line width, the compounding ratio of the polymerization initiator system is increased so as to cancel the expected deviation width from the compounding of the base vehicle based on the correlation equation.

Further, for example, when canceling the expected deviation width by using a polymerization inhibitor, first prepare a correlation equation between the compounding ratio of the polymerization inhibitor and the solid line width as the second correlation equation. In this correlation equation, it is assumed that the compounding ratio of the polymerization inhibitor and the solid line width have a negative correlation. In this case, if the expected line width is larger than the target line width, the compounding ratio of the polymerization inhibitor is increased so as to cancel the expected deviation width from the compounding of the base vehicle based on the correlation equation. If the expected line width is smaller than the target line width, the compounding ratio of the polymerization inhibitor is reduced so as to cancel the expected deviation width from the compounding of the base vehicle based on the correlation equation. As described above, the compounding ratio of the organic component in the photosensitive composition is determined.

The organic component for which the compounding ratio is adjusted in this step is not limited to the components (A) to (D) described above. For example, the compounding ratio of at least one of the photocurable resin and the photocurable compound described later may be adjusted as long as other performances (for example, the tackiness of the conductive film with respect to the substrate) are not significantly deteriorated. Further, for example, the blending ratio of other additive components described later may be adjusted.

<(Step S4) Preparation step of photosensitive composition>
In this step, a photosensitive composition is prepared using the conductive powder whose average particle size was actually measured in step S1. For example, first, an organic binder, a photocurable compound, a photopolymerization initiator, a sensitizer, a light absorber, a polymerization inhibitor, and other additive components used as needed are mixed as an organic dispersion medium. Mix in to prepare a liquid vehicle. At this time, each component is added so that the photosensitive composition has the blending ratio determined in step S3. Next, the conductive powder and the vehicle are mixed at a predetermined blending ratio. This prepares a photosensitive composition. In the present embodiment, it is possible to obtain a photosensitive composition (paste-like photosensitive composition) containing an organic dispersion medium and prepared in the form of a paste (including slurry-like and ink-like).

The organic binder (polymer component) is a component that enhances the adhesiveness between the base material and the uncured conductive film. The organic binder may or may not have photosensitive (a property of causing a chemical or structural change by light, for example, photocurability). The organic binder includes a photopolymerizable oligomer (prepolymer) having a weight average molecular weight of 2000 or more and less than 5000, and a photopolymerizable polymer having a weight average molecular weight of 5000 or more. As the organic binder, one of the conventionally known binders can be used alone or two or more thereof can be appropriately used depending on, for example, the base material, the photopolymerizable compound, the type of the photopolymerization initiator, and the like. .. The organic binder is preferably one that can be easily removed with a developing solution in the developing step. For example, when an alkaline developer is used in the developing process, a hydroxyl group (-OH), a carboxyl group (-C (= O) OH), an ester bond (-C (= O) O-), and a sulfo group. of _(-SO 3 H) or the like, a compound having a structural part showing acidity are preferable. As a result, the residue is less likely to remain in the unexposed portion, and for example, a space between fine lines can be stably secured.

Preferable examples of organic binders include cellulosic polymers such as methyl cellulose, ethyl cellulose, carboxymethyl cellulose and hydroxymethyl cellulose, acrylic resins, phenol resins, alkyd resins, polyvinyl alcohol, polyvinyl butyral and the like. Of these, hydrophilic organic binders such as cellulosic polymers and acrylic resins are preferable from the viewpoint of easy removal in the developing process.

Further, a photocurable resin may be used as the organic binder. A photocurable resin is a photocurable component that is polymerized and cured by an active species generated from a photopolymerization initiator. Photocurable resins typically have at least one of unsaturated bonds and a cyclic structure. As the photocurable resin, one of the conventionally known ones can be used alone, or two or more of them can be used in combination as appropriate. Typical examples include resins having an ethylenic double bond such as a (meth) acryloyl group, a vinyl group, and an allyl group, such as an acrylic resin and an epoxy resin. In addition, in this specification, "(meth) acryloyl" is a term including "methacryloyl" and "acryloyl".

Specific examples of the acrylic resin include homopolymers of alkyl (meth) acrylates such as polymethyl (meth) acrylate, polyethyl (meth) acrylate, and polybutyl (meth) acrylate, and alkyl (meth) acrylate as the main monomer (largest mass ratio). Examples of the monomer) include a copolymer containing a submonomer having copolymerizability in the main monomer.

A photocurable compound (monomer component) is a photocurable component that is polymerized and cured by an active species generated from a photopolymerization initiator. The polymerization reaction may be, for example, addition polymerization or ring-opening polymerization. The photocurable compound may be radically polymerizable or cationically polymerizable. The photocurable compound is a monomer having a weight average molecular weight of less than 2000. As the photocurable compound, one of the conventionally known compounds can be used alone, or two or more thereof can be used in combination as appropriate. A typical example is a (meth) acrylate monomer having a (meth) acryloyl group. The (meth) acrylate monomer includes a monofunctional (meth) acrylate having one functional group per molecule, a polyfunctional (meth) acrylate having two or more functional groups per molecule, and modified products thereof. To do. Specific examples of the (meth) acrylate monomer include polyfunctional (meth) acrylate, urethane-modified (meth) acrylate having a urethane bond, epoxy-modified (meth) acrylate, silicone-modified (meth) acrylate, and the like. In addition, in this specification, "(meth) acrylate" is a term including "methacrylate" and "acrylate".

The organic dispersion medium is a component that imparts appropriate viscosity and fluidity to the photosensitive composition and improves the handleability of the photosensitive composition and the workability when molding the conductive film. As the organic dispersion medium, one of the conventionally known ones can be used alone, or two or more of them can be used in combination as appropriate. Typical examples include organic solvents such as alcohol solvents, glycol solvents, ether solvents, ester solvents, hydrocarbon solvents, and mineral spirits. Among them, an organic solvent having a boiling point of 150 ° C. or higher, and further an organic solvent having a boiling point of 170 ° C. or higher are preferable from the viewpoint of improving the storage stability of the photosensitive composition and the handleability at the time of molding the conductive film. Further, as another preferable example, from the viewpoint of keeping the drying temperature after printing the conductive film low, an organic solvent having a boiling point of 250 ° C. or lower, and further an organic solvent having a boiling point of 220 ° C. or lower are preferable.

As the other additive component, one of the conventionally known components can be used alone, or two or more thereof can be used in combination as appropriate. As an example, antioxidants, plasticizers, surfactants, leveling agents, thickeners, wetting agents, dispersants, defoamers, antistatic agents, antigels, preservatives, fillers (organic or inorganic fillers). ), Glass powder, ceramic powder (Al ₂ O ₃ , ZrO ₂ , SiO _2, etc.), organic metal compound (metal resinate) and the like.

In the present embodiment, the blending ratio of the conductive powder in the photosensitive composition is predetermined. Although not particularly limited, the blending ratio of the conductive powder may be approximately 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 having high density and electrical conductivity can be formed. In addition, the handleability of the photosensitive composition and the workability when molding the conductive film can be improved.

Although not particularly limited, the proportion of the polymerization initiator system in the entire photosensitive composition is approximately 5% by mass or less, typically 0.01 to 1% by mass, for example 0.02 to 0.5. It may be mass%, 0.05 to 0.2 mass%. The proportion of the light absorber may be approximately 0.5% by mass or less, typically 0.1% by mass or less, for example, 0.01% by mass or less, and further may be 0.001% by mass or less. The proportion of the polymerization inhibitor may be approximately 0.5% by mass or less, typically 0.1% by mass or less, for example 0.001% by mass or less. The proportion of the photocurable resin in the entire photosensitive composition is approximately 5% by mass or less, typically 0.01 to 1% by mass, for example 0.02 to 0.5% by mass, 0.03 to 0.03 to It may be 0.2% by mass. The proportion of the photocurable compound in the entire photosensitive composition is approximately 5% by mass or less, typically 0.01 to 1% by mass, for example 0.02 to 0.5% by mass, 0.03 to 0.03 to It may be 0.2% by mass. The blending ratio of the photocurable resin and the photocurable compound may be approximately 1:10 to 10: 1, for example, 1: 3 to 3: 1, and further 1: 2 to 2: 1. The proportion of the organic dispersion medium may be approximately 1 to 50% by mass, typically 3 to 30% by mass, for example, 5 to 20% by mass. Moreover, the ratio of other additive components may be about 5% by mass or less, for example, 3% by mass or less.

≪Application of photosensitive composition≫
According to the photosensitive composition disclosed herein, it is possible to stably form a conductive layer having an L / S finer than 30 μm / 30 μm and further having an L / S finer than 20 μm / 20 μm. Therefore, the photosensitive composition disclosed herein can be suitably used for forming a conductive layer in various electronic components such as an inductance component, a capacitor component, and a multilayer circuit board. The electronic component may be of various mounting forms such as a surface mount type and a through-hole mount type. The electronic component may be a laminated type, a wound type, or a thin film type. Typical examples of inductance components include high-frequency filters, common-mode filters, inductors for high-frequency circuits (coils), inductors for general circuits (coils), high-frequency filters, choke coils, transformers, and the like.

Further, a photosensitive composition in which the conductive powder contains metal-ceramic core-shell particles can be suitably used for forming a conductive layer of a ceramic electronic component. In the present specification, the "ceramic electronic component" includes all electronic components having an amorphous ceramic base material (glass ceramic base material) or a crystalline (that is, non-glass) ceramic base material. As a typical example, a high-frequency filter having a ceramic base material, a ceramic inductor (coil), a ceramic capacitor, a low-temperature co-fired ceramics substrate (LTCC base material), and a high-temperature fired laminated ceramic base material (LTCC base material) High Temperature Co-fired Ceramics Substrate (HTCC base material) and the like can be mentioned.

FIG. 3 is a cross-sectional view schematically showing the structure of the laminated chip inductor 10. The dimensional relationship (length, width, thickness, etc.) in FIG. 3 does not necessarily reflect the actual dimensional relationship. Further, the reference numerals X and Y in the drawings represent the horizontal direction and the vertical direction, respectively. However, this is just for convenience of explanation.

The laminated chip inductor 10 includes a main body portion 11 and external electrodes 20 provided on both side surface portions of the main body portion 11 in the left-right direction X. The shape of the laminated chip inductor 10 is, for example, a size such as 1608 shape (1.6 mm × 0.8 mm) or 2520 shape (2.5 mm × 2.0 mm). The main body 11 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, for example, a ceramic material as described above as being capable of forming a coating portion of a conductive powder. In the vertical direction Y, the internal electrode layer 14 is arranged between the ceramic layers 12. The internal electrode layer 14 is formed by using the above-mentioned photosensitive composition. The internal electrode layers 14 adjacent to each other in the vertical direction Y with the ceramic layer 12 interposed therebetween are conducted through vias 16 provided in the ceramic layer 12. As a result, the internal electrode layer 14 is formed in a three-dimensional spiral shape (spiral shape). Both ends of the internal electrode layer 14 are connected to the external electrode 20.

The laminated chip inductor 10 can be manufactured, for example, by the following procedure. That is, first, a paste containing a ceramic material as a raw material, a binder resin, and an organic solvent is prepared and supplied onto a carrier sheet to form a ceramic green sheet. Next, after rolling this ceramic green sheet, it is cut to a desired size to obtain a plurality of ceramic layer forming green sheets. Next, via holes are appropriately formed at predetermined positions of the plurality of ceramic layer forming green sheets by using a drilling machine or the like. Next, using the above-mentioned photosensitive composition, a conductive film having 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 step: (Step A) A step of forming a conductive film made of a dried product of the photosensitive composition by applying the photosensitive composition on a green sheet for forming a ceramic layer and drying it; (step). B) A step of covering the conductive film with a photomask having a predetermined opening pattern, exposing the conductive film through the photomask, and partially photocuring the conductive film: (step C) The conductive film after photocuring has not been etched. By a production method including the step of removing the cured portion; the conductive film in an unfired state can be formed.

In forming a conductive film using the above photosensitive composition, a conventionally known method can be appropriately used. For example, in (Step A), the photosensitive composition can be applied by using various printing methods such as screen printing, a bar coater, or the like. Drying of the photosensitive composition is typically carried out at 50-100 ° C. In (step B), an exposure machine that emits radiation such as visible light, ultraviolet rays, X-rays, electron beams, α rays, β rays, and γ rays can be used for exposure. As an example, an exposure machine that emits light rays in the wavelength range of 10 to 400 nm, for example, an ultraviolet irradiation lamp such as a high-pressure mercury lamp, a metal halide lamp, or a xenon lamp can be used. In (step C), an aqueous solution containing an alkaline component such as sodium hydroxide or sodium carbonate can be used for etching.

Next, a plurality of green sheets for forming a ceramic layer on which a conductive film in an unfired state is formed are laminated and pressure-bonded. As a result, a laminated body of unfired ceramic green sheets is produced. Next, the laminated body of the ceramic green sheet is fired at, for example, 600 to 1000 ° C. As a result, the ceramic green sheet is integrally sintered, and the main body 11 including the ceramic layer 12 and the internal electrode layer 14 made of the fired body of the photosensitive composition is formed. Then, an appropriate external electrode forming paste is applied to both ends of the main body portion 11 and fired to form the external electrode 20. In this way, the laminated chip inductor 10 can be manufactured.

≪Mixing ratio determination device≫
FIG. 4 is a functional block diagram of the compounding ratio determining device 30. The blending ratio determining device 30 disclosed here includes an input unit 31, a storage unit 32, a first calculation unit 33, a second calculation unit 34, and a display unit 35. Each part of the compounding ratio determining device 30 is configured to be able to communicate with each other. Each part of the compounding ratio determining device 30 may be composed of software or hardware. Each part of the compounding ratio determining device 30 may be performed by a processor or may be incorporated in a circuit.

The input unit 31 can receive an operation input of a user (for example, a worker who prepares a photosensitive composition) and input the type and average particle size (measured value) of the conductive powder to be used and the target line width. It is configured as follows. When a plurality of conductive powders are used in combination, the mixing ratio thereof can be further input. The type of the conductive powder is, for example, information represented by a purchaser, an item name (product name), a product number, or the like. The type of conductive powder is, for example, information represented by physical properties such as the structure of the conductive powder (whether or not it has a core-shell structure), average particle size (nominal value), average aspect ratio, and brightness L ^*. May be good. The input unit 31 includes, for example, a keyboard having cursor keys, number input keys, and the like, a pointing device such as a mouse, and an input device (not shown) such as buttons. The input unit 31 may be configured so that the type of the conductive powder can be selected from, for example, the pull-down menu displayed on the display unit 35. The input unit 31 may be configured so that the above-mentioned information can be taken in from an external device such as a host computer or a network connected by wire or wirelessly. In this embodiment, the "target line width" is an example of a predetermined target level.

The storage unit 32 stores the first correlation equation and the second correlation equation. The first correlation equation and the second correlation equation are stored in advance in the storage unit 32 for each type of conductive powder (for example, for each product name). Therefore, the first correlation equation and the second correlation equation stored in the storage unit 32 are typically a plurality of each. The first correlation equation may be expressed by a linear function. Although not particularly limited, the first correlation equation is, for example, a correlation equation between the average particle size (actual measurement value) of the above-mentioned conductive powder and the solid line width. The second correlation equation has a predetermined slope (rate of change). The second correlation equation may be expressed by a linear function. Although not particularly limited, the second correlation equation is, for example, a correlation equation between the compounding ratio of the above-mentioned organic component (for example, a polymerization initiator system) and the solid line width. The storage unit 32 may further store the composition of the base vehicle, that is, the type and blending ratio of each organic component contained in the vehicle.

When the user inputs the type of conductive powder to be used and the average particle size (actual measurement value) from the input unit 31, the first calculation unit 33 stores the first correlation in the storage unit 32. From the formulas, the first correlation formula relating to the same type of conductive powder as the input conductive powder is referred to. Then, the expected deviation width with respect to the target line width is calculated from the average particle size (actual measurement value) input to the input unit 31. For example, when the first correlation equation is expressed by the correlation equation between the average particle size (actual measurement value) of the conductive powder and the solid line width, the average particle size (actual measurement value) input to the input unit 31 is first corresponded. The expected line width is calculated by interpolating into the first correlation equation. Then, the difference between the expected line width and the target line width input from the input unit 31 by the user is calculated as the expected deviation width. In this embodiment, the "expected deviation width" is an example of the expected deviation value.

When the expected deviation width is calculated by the first calculation unit 33, the second calculation unit 34 has the same type of conductivity as the input conductive powder from the second correlation equation stored in the storage unit 32. Refer to the second correlation equation for powder. Then, the compounding ratio of the organic component is calculated based on the expected deviation width calculated by the first calculation unit 33. For example, when the second correlation equation is indicated by the correlation equation between the compounding ratio of the polymerization initiator system and the solid line width, the expected deviation width is divided by the slope of the second correlation equation to cancel the expected deviation width. Calculate the compounding ratio of the polymerization initiator system. Then, the compounding ratio for canceling the expected deviation width is increased or decreased from the compounding ratio of the photopolymerization initiator system contained in the vehicle to obtain the final compounding ratio.

The compounding ratio determining device 30 is, for example, a computer, and stores an interface (I / F) for a user, a central processing unit (CPU: central processing unit) that executes instructions of a control program, and a program executed by the CPU. It is equipped with a CPU (read only memory), a RAM (random access memory) used as a working area for deploying programs, and a storage device such as a memory for storing the above programs and various data. The compounding ratio determining device 30 may be a computer program configured to operate the CPU of the computer as each part of the compounding ratio determining device 30. Such a computer program may be a recording medium on which the operation of the compounding ratio determining device 30 is written and can be read by a computer.

Examples of the recording medium include a semiconductor recording medium (for example, ROM, non-volatile memory card), an optical recording medium (for example, DVD, MO, MD, CD, BD), and a magnetic recording medium (for example, magnetic tape, flexible disk). Etc. are exemplified. Further, the computer program can be transmitted to the server computer via the recording medium or a network such as the Internet or an intranet. In this case, the server computer is also a form of the compounding ratio determining device 30.

Hereinafter, some examples of the present invention will be described, but the present invention is not intended to be limited to those shown in the examples.

<Example 1: When one kind of conductive powder is used alone>
Hereinafter, a case where a photosensitive composition is produced by using one kind of conductive powder alone will be described. Here, as a preliminary preparation, first, a first correlation equation and a second correlation equation corresponding to the conductive powder to be used were prepared. Specifically, the first correlation equation shown in FIG. 5 and the second correlation equation shown in FIG. 6 were prepared. FIG. 6 is a second correlation equation for adjusting the compounding ratio of the photopolymerization initiator system.

The first correlation equation shown in FIG. 5 was prepared as follows. That is, first, as conductive powder, a plurality of commercially available silver powders (15 types in this case) having an average particle size (nominal value) of about 3 μm were prepared. Next, a wet measurement in a dispersion solvent is performed using a particle size distribution measuring device (model "MT-3000II" manufactured by Microtrac Bell Co., Ltd., measuring range: 0.02 to 2800 μm) based on the laser diffraction / scattering method. The average particle size of each of the 15 types of silver powder was actually measured. As the dispersion solvent, an alcohol solvent (specifically, ethanol) was used from the viewpoint of suppressing aggregation of the silver powder and dispersing individual particles in the dispersion solvent. Then, a volume-based particle size distribution was obtained. The particle size distribution was typically monomodal with only one mode diameter (mode diameter). From the particle size distribution, the average particle size (measured value) of 15 types of silver powder was read.

Next, an organic binder, a photocurable compound, a photopolymerization initiator, a sensitizer, an ultraviolet absorber as a light absorber, and a polymerization inhibitor were added to an organic dispersion medium having the composition shown in Table 1. It was melted and a vehicle was prepared. Next, the 15 kinds of silver powders prepared above and the vehicle were mixed at a mass ratio of 77:23 to prepare photosensitive compositions.

Next, the photosensitive composition prepared above was applied onto a commercially available ceramic green sheet by screen printing. Next, this was dried at 60 ° C. for 15 minutes to form a conductive film (solid film) on the green sheet (conductive film forming step). Next, a photomask was put on the conductive film. As the photomask, one with L / S = 25 μm / 25 μm was used. With this photomask covered on the conductive film, light was irradiated with an intensity of 2500 mJ / cm ² by an ultraviolet exposure machine to partially cure the conductive film (exposure step). After the exposure, a 0.4% by mass Na ₂ CO ₃ aqueous solution was sprayed on the ceramic green sheet, the uncured conductive film portion was removed by etching, washed with pure water, and dried at room temperature (development step). In this way, the wiring pattern was formed on the ceramic green sheet.

Next, the wiring pattern was observed with a laser microscope, and the line width of the wiring was measured from the obtained observation image. The line width was measured for multiple fields of view, and the arithmetic mean value was taken as the solid line width (actual line width). Then, as shown in FIG. 5, the correlation between the average particle size (actual measurement value) of the 15 types of silver powder and the solid line width was shown in a graph, and the correlation equation (Y = 5.593X + 11.192) was calculated. In the first correlation equation shown in FIG. 5, the average particle size (measured value) of the silver powder is proportional to the solid line width obtained by using the photosensitive composition containing the silver powder (correlation coefficient: 0.92). doing. The first correlation equation shown in FIG. 5 is represented by a linear function. In FIG. 5, the average particle size (measured value) and the solid line width have a positive correlation. That is, as the average particle size (measured value) of the silver powder increases, the line width increases linearly.

The second correlation equation in FIG. 6 was prepared as follows. That is, first, a predetermined silver powder was prepared as the conductive powder. Further, an organic binder, a photocurable compound, a photopolymerization initiator, a sensitizer, an ultraviolet absorber, a polymerization inhibitor, and an organic dispersion medium are mixed at the blending ratios shown in Table 1 above. I prepared a base vehicle. Next, the silver powder and the vehicle were mixed at a mass ratio of 77:23 to prepare a base photosensitive composition.

Next, the compounding ratio of the photopolymerization initiator system (photopolymerization initiator and sensitizer) was changed from the base photosensitive composition as shown in Table 2. At this time, the amount by which the compounding ratio of the photopolymerization initiator was increased or decreased was adjusted by increasing or decreasing the amount of the organic dispersion medium. For example, when the compounding ratio of the photopolymerization initiator system was reduced from 0.550 to 0.515, the amount of the organic dispersion medium was increased by that amount (0.035). A plurality of such photosensitive compositions (here, 5 patterns) were prepared. When the compounding ratio of the photopolymerization initiator system was changed, the ratio of the photopolymerization initiator and the sensitizer was kept constant. Next, using the plurality of photosensitive compositions prepared above, a wiring pattern was formed in the same manner as in the calculation of the first correlation equation described above, and the solid line width was determined. Then, the correlation between the compounding ratio of the photopolymerization initiator in the five patterns of the photosensitive composition and the solid line width was shown in a graph, and the correlation equation (Y = 74.927X + 19.762) was calculated.

In the second correlation equation of FIG. 6, the compounding ratio of the polymerization initiator system in the photosensitive composition and the solid line width are proportional (correlation coefficient: 0.96). The second correlation equation in FIG. 6 is represented by a linear function. In FIG. 6, the compounding ratio of the polymerization initiator system and the solid line width have a positive correlation. That is, it can be seen that the line width increases linearly as the compounding ratio of the polymerization initiator system increases.

In Example 1, after aligning the first correlation equation and the second correlation equation as described above, silver powder (average particle size (nominal value): 3 μm) used for the photosensitive composition is prepared as step S1. did. Next, the average particle size of the silver powder was actually measured under the same measurement and analysis conditions using the same particle size distribution measuring device as when calculating the first correlation equation. Then, the average particle size (measured value) of the silver powder was read from the volume-based particle size distribution. Here, the measured value was 3.17 μm.

Next, as step S2, the actually measured value obtained in step S1 was compared with the first correlation equation of FIG. Then, the expected deviation width with respect to the predetermined target line width was confirmed. Here, when the measured value of 3.17 μm is interpolated into the first correlation equation (Y = 5.593X + 11.192) in FIG. 5, the expected line width is calculated to be 28.92 μm. Therefore, when the target line width is 27.3 μm, the expected deviation width is calculated as +1.62 μm by (expected line width 28.92 μm) − (target line width 27.3 μm). That is, it can be seen that if the photosensitive composition is prepared with the same vehicle composition as the base as it is, there is a high possibility that the line width becomes thicker by 1.62 μm from the target line width.

Therefore, next, in step S3, the blending ratio of the organic components was changed so as to cancel the expected deviation width and bring it closer to the target line width. Here, the compounding ratio of the polymerization initiator system was adjusted based on the second correlation equation (Y = 74.927X + 19.762) in FIG. That is, the value obtained by dividing the expected deviation width +1.62 μm by the slope 74.927 of the second correlation equation (= 1.62 / 74.927) = +0.022 is the amount of the polymerization initiator system that adjusts the expected deviation width +1.62 μm. It becomes. Therefore, in order to cancel the expected deviation width, the proportion of the polymerization initiator system was reduced by 0.022% by mass from the photosensitive composition of the base. Table 3 shows an example of the compounding ratio of the polymerization initiator system determined in consideration of the expected deviation width.

Next, as step S4, a vehicle in which the compounding ratio of the polymerization initiator system was changed was prepared as shown in Table 3. The organic components not listed in Table 3, for example, an organic binder, a photocurable compound, an ultraviolet absorber, and a polymerization inhibitor, are the same as the formulation of the base photosensitive composition. Next, the silver powder whose average particle size was actually measured in step S1 and the vehicle were mixed to prepare a photosensitive composition. Then, a wiring pattern was formed and the solid line width was measured. As a result, the solid line width was 27.4 μm. That is, the result was that the line width (27.3 μm) was much closer than the line width (29.0 μm) expected in step S2.

For several more types of conductive powders, a photosensitive composition was prepared by applying the technique disclosed here in the same manner as above, and the solid line width was measured. That is, after obtaining the measured value of the average particle size of the silver powder in step S1, confirming the expected deviation width in step S2, determining the blending ratio of the polymerization initiator system in step S3, and adjusting the blending of the vehicle. , A photosensitive composition was prepared, and the solid line width was measured. The results are shown in Table 4. The right end of Table 4 is the result of Example 1 described above. Further, as a reference example, the solid line width (μm) when the base vehicle is used as it is (that is, the compounding ratio of the polymerization initiator system is kept constant without adjusting) without applying the technique disclosed here. Is listed at the bottom.

FIG. 7 is a graph summarizing the results of Table 4 and comparing the solid line widths with and without the application of the technology disclosed here. As is clear from FIGS. 7 and 4, by applying the techniques disclosed herein, the production lot of the conductive powder is relatively higher than that in the case where the techniques disclosed here are not applied (reference example). It was possible to suppress the variation in line width by buffering the fluctuation between them. Here, the fluctuation of the line width could be suppressed to ± 1 μm or less, and further to ± 0.5 μm or less. In other words, the fine wire-shaped wiring could be stably formed near the target line width. Such results show the significance of the techniques disclosed herein.

<Example 2: When two types of conductive powders are mixed and used>
Hereinafter, a case where a photosensitive composition is produced using a mixed powder obtained by mixing two types of conductive powders will be described. Here, as a preliminary preparation, first, two first correlation equations corresponding to the two conductive powders to be used were prepared. Specifically, the first correlation equation shown by the solid line is prepared in FIGS. 8 and 9. In addition, a second correlation equation was also prepared. As the second correlation equation, the same one as shown in FIG. 6 was prepared.

The first correlation equation shown by the solid line in FIG. 8 is prepared as follows. That is, first, as the first conductive powder, a plurality of first silver powders (here, seven types) having an average particle size (nominal value) of about 2.9 μm were prepared. Then, the average particle size (measured value) of the seven types of first silver powder was actually measured in the same manner as in the calculation of the first correlation equation of FIG. 5 of Example 1 described above. Further, as the second conductive powder, a second silver powder having an average particle size (measured value) of 2.56 μm was prepared. Next, the mixed powder was prepared by mixing the first silver powder and the second silver powder at a mass ratio of a predetermined ratio (here, 40:60). A photosensitive composition was prepared by mixing this mixed powder with the vehicle shown in Table 1 at a mass ratio of 77:23. Next, using this photosensitive composition, a wiring pattern is formed in the same manner as in Example 1 described above, and a correlation equation (Y = 1.89X + 24.85) between the average particle size (measured value) and the solid line width is calculated. did.

The first correlation equation shown by the solid line in FIG. 9 was prepared as follows. That is, first, as the second conductive powder, a plurality of second silver powders (here, five types) having an average particle size (nominal value) of about 2.4 μm were prepared. Then, the average particle size (actual measurement value) of the five types of second silver powder was actually measured in the same manner as in the calculation of the first correlation equation of FIG. 5 of Example 1 described above. Further, as the first conductive powder, a first silver powder having an average particle size (measured value) of 3.06 μm was prepared. Next, the mixed powder was prepared by mixing the first silver powder and the second silver powder at a mass ratio of 40:60. Then, the correlation equation (Y = 2.12X + 24.72) between the average particle size (measured value) and the solid line width was calculated in the same manner as in the calculation of the first correlation equation in FIG.

In the first correlation equation shown by the solid lines in FIGS. 8 and 9, the average particle size (actual measurement value) of the changed silver powder and the solid line width are proportional to each other, as in the first correlation equation of FIG. 5 in Example 1. (Correlation coefficient: 0.92 or more). The first correlation equation shown by the solid line in FIGS. 8 and 9 is shown by a linear function. In FIGS. 8 and 9, the average particle size (measured value) and the solid line width have a positive correlation.

In Example 2, after preparing the two first correlation equations as described above, as step S1, the first silver powder (average particle size (nominal value): 2.9 μm) and the first silver powder used in the photosensitive composition are used. Two types of conductive powders of 2 silver powder (average particle size (nominal value): 2.4 μm) were prepared. Next, the average particle diameters of the first silver powder and the second silver powder were actually measured in the same manner as in the calculation of the first correlation equations in FIGS. 8 and 9. Next, in step S2, the actually measured value of the first silver powder obtained in step S1 was compared with the first correlation equation (Y = 1.89X + 24.85) in FIG. In addition, the measured values of the second silver powder were compared with the first correlation equation (Y = 2.12X + 24.72) in FIG. Next, for each of the two types of silver powder, the expected deviation widths α1 and α2 with respect to the target line width (here, set to 30.0 μm) were calculated. That is, assuming that the measured values of the first silver powder and the second silver powder are x1 and x2 and the expected line widths are y1 and y2, the expected deviation widths α1 and α2 are obtained from the following equations.
α1 = y1-30.0 = 1.89 × x1 + 24.85-30.0
α2 = y2-30.0 = 2.12 × x2 + 24.72-30.0

Then, the expected deviation width β (μm) when the two types of conductive powders were mixed and used was calculated from the following formula using the above expected deviation widths α1 and α2.
β = α1 + α2

Next, as step S3, the compounding ratio of the polymerization initiator system contained in the vehicle was adjusted as shown in Tables 5 and 6 in the same manner as in Example 1 described above. Next, as step S4, a photosensitive composition was prepared in the same manner as in Example 1 described above. Then, a wiring pattern was formed and the solid line width was measured.

As is clear from Tables 5 and 6, by applying the techniques disclosed herein, even when two types of conductive powders are mixed and used, fluctuations between production lots of the conductive powders are buffered. , I was able to suppress the variation in line width. Here, the fluctuation of the line width could be suppressed to ± 1 μm or less, and further to ± 0.5 μm or less.

The first correlation equation shown by the broken line in FIGS. 8 and 9 is a case where the first silver powder and the second silver powder are mixed at a mass ratio of 70:30, respectively. Even when the mixing ratio is changed in this way, the average particle size (actual measurement value) of the changed silver powder and the solid line width are proportional to each other by a linear function, as in the first correlation equation shown by the solid line. (Correlation coefficient: 0.95 or more). The average particle size (measured value) and the solid line width have a positive correlation. From this, it is considered that the techniques disclosed herein can be applied to various mixed powders regardless of the mixing ratio.

The preferred embodiment of the present invention has been described above. However, the above-described embodiment is merely an example, and the present invention can be implemented in various other embodiments. The present invention can be carried out based on the contents disclosed in the present specification and common general technical knowledge in the art. The techniques described in the claims include various modifications and modifications of the embodiments illustrated above. For example, it is possible to combine some of the above-described embodiments or replace them with other modifications. Further, if the technical feature is not explained as essential, it can be deleted as appropriate.

In the above embodiment, the target level factor was defined by the "line width", but the factor is not limited to this. The target level factor may be due to the light absorption degree or the photocurability of the conductive film, and may be, for example, the film thickness of the conductive film, the electrode cross-sectional area, the curing shrinkage rate, the resistance value, or the like. That is, from FIGS. 1 (A) and 1 (B), the scattering of light changes depending on the difference in the particle size of the conductive powder, and as a result, the light absorption of the conductive film changes, so that the degree of photocurability changes. You can see that it does. From this point of view, it is clear to those skilled in the art that not only the above-mentioned line width but also the film thickness, cross-sectional area, curing shrinkage rate and the like can be similarly changed by the difference in the particle size of the conductive powder. It is also apparent to those skilled in the art that the resistance value can change accordingly.

This means, for example, the following references 1 to 3:
Reference 1: Takashi Ukaji, CMC Technical Library 206, Plastic Surface Treatment Technology and Materials, P.M. 67, Correlation diagram between the light transmittance (%) of the coating film and the particle size (μm);
-Reference 2: Yamamoto Precious Metal Bullion Co., Ltd., Polymer Technology Report, Vol. 5 (2011), P.M. 20, FIG. 15 (Relationship between the reaction rate of hexanediol diacrylate and the curing time when the intensity of irradiation light is changed);
-Reference 3: Published by Information Technology Association, UV curable resin formulation design, characterization and new applications, P.M. 470, FIG. 16 (change in film thickness during curing shrinkage of UV resist);
It is thought that this is also supported by such factors.

Considering the description in the above literature, it is clear that, for example, in the range of 0.1 to 10 μm, the factors of light absorption and photocurability increase or decrease monotonically as the particle size of the conductive powder changes. Is presumed to be. That is, it is considered that the fluctuation of the line width due to the displacement of the particle size and their displacement have a high correlation with a proportional or constant function. From the above, it can be said that buffering variations in line width is synonymous with suppressing variations in factors related to light absorption and photocuring. That is, in the technique disclosed herein, the "target level" may be a target line width, a target film thickness, a target cross-sectional area, a target curing shrinkage rate, or a target resistance value. It is considered well. In addition, the "expected deviation value" may be the deviation width, the deviation thickness, the deviation cross-sectional area, the deviation curing shrinkage rate, or the deviation resistance value according to the target level. Conceivable.

In the above-described embodiment, step S3 was carried out after step S2, but the present invention is not limited to this. For example, after step S2, a determination step of comparing the expected deviation width with the preset threshold value may be included. Then, when it is determined in the determination step that the expected deviation width is smaller than the threshold value, step S3 may be omitted and step S4 may be performed.

In the above-described embodiment, the correlation equation between the average particle size (measured value) and the solid line width is exemplified as the first correlation equation, but the present invention is not limited to this. As a variable to be compared with the average particle size (measured value), for example, the expected deviation width obtained by subtracting the target line width from the solid line width may be used. That is, the first correlation equation may be expressed by a correlation equation between the average particle size (measured value) and the expected deviation width. In this case, the measured value obtained in step S1 may be interpolated into the correlation equation to directly confirm the expected deviation width.

In the above-described embodiment, as the second correlation equation, the correlation equation between the compounding ratio of the organic component in the photosensitive composition and the solid line width is exemplified, but the present invention is not limited to this. As a variable to be compared with the compounding ratio of the organic component, for example, the expected deviation width may be used as in the case of the first correlation equation. Further, the compounding ratio of the organic component may be expressed not in the photosensitive composition but in, for example, the compounding ratio in the vehicle.

In the above-described embodiment, the blending ratio determining device 30 includes an input unit 31, a storage unit 32, a first calculation unit 33, and a second calculation unit 34, but the present invention is not limited thereto. In addition to the above-mentioned parts, the compounding ratio determining device 30 sets at least one of the following: a first setting unit that sets a first correlation equation for a predetermined type of conductive powder and stores it in the storage unit 32; A second setting unit that sets a second correlation equation for the type of conductive powder and stores it in the storage unit 32; a first correlation equation or a second correlation equation of the same type as the input conductive powder is stored in the storage unit. A notification unit; or the like, which notifies the user of an error when it is not stored in 32 may be provided.

In Examples 1 and 2 described above, silver powder was used as the conductive powder, but the present invention is not limited to this. The mechanism that when a conductive powder having a large average particle size is used, the irradiation light tends to spread in the horizontal direction of the conductive film in the exposure process and the line width of the wiring tends to be thick is the same for other metal types. .. Of course, the technique disclosed herein can be applied not only to silver powder but also to powders containing the above-mentioned various metals such as copper, platinum, palladium, aluminum and nickel.

In Examples 1 and 2 described above, in step S1, the average particle size (D50 particle size) of the conductive powder, specifically, corresponds to an integrated value of 50% from the smaller particle size side in the volume-based particle size distribution. The particle size was measured, but is not limited to this. In step S1, a number-based particle size distribution or the like may be used instead of the volume-based particle size distribution. The particle size factor is, for example, D40 particle size (particle size corresponding to the integrated value of 40% from the smaller particle size side in the particle size distribution) and D60 particle size (particle size) instead of the average particle size (D50 particle size). The particle size may be such that the particle size corresponds to an integrated value of 60% from the side with the smallest particle size in the distribution. In this case, the first correlation equation may be represented by "D40 particle size (measured value) X-solid line width Y", "D60 particle size (measured value) X-solid line width Y", or the like. Further, for example, when the particle size distribution of the conductive powder is monomodal, the particle size factor is a particle size further distant from the average particle size, for example, D5 particle size (integrated from the smaller particle size side in the particle size distribution). Particle size corresponding to a value of 5%), D90 particle size (particle size corresponding to an integrated value of 90% from the smaller particle size side in the particle size distribution), D95 particle size (integrated value 90 from the smaller particle size side in the particle size distribution) The particle size corresponding to%) may be used.

In Examples 1 and 2 described above, in step S3, a second correlation equation relating to the polymerization initiator system was prepared, and the blending ratio of the photopolymerization initiator system was adjusted to suppress the variation in line width. , Not limited to this. The organic component for which the compounding ratio is adjusted may be, for example, either a photopolymerization initiator or a sensitizer.

Further, in Examples 1 and 2 described above, the second correlation equation relating to the polymerization initiator system was prepared in step S3, but instead of or in addition to this, for example, the second correlation relating to the light absorber. By preparing a formula (see FIG. 10) and adjusting the compounding ratio of the light absorber, it is possible to suppress variations in line width. In the second correlation equation shown in FIG. 10, the compounding ratio of the ultraviolet absorber in the photosensitive composition and the solid line width are shown by a logarithmic curve. Since the logarithmic curve changes rapidly, for example, when the expected deviation width is large, there is an advantage that only a slight change in the compounding ratio is required. Further, for example, by preparing a second correlation equation (see FIG. 11) relating to the polymerization inhibitor and adjusting the blending ratio of the polymerization inhibitor, variation in line width can be suppressed. In the second correlation equation shown in FIG. 11, the compounding ratio of the photopolymerization inhibitor in the photosensitive composition and the solid line width are proportional (correlation coefficient: 0.99). The second correlation equation shown in FIG. 11 is represented by a linear function. The compounding ratio of the polymerization inhibitor and the solid line width have a negative correlation. That is, it can be seen that the line width becomes linearly narrower as the compounding ratio of the polymerization inhibitor system increases. Such a second correlation equation can also be suitably used in the technique disclosed herein, similarly to the second correlation equation of FIGS. 6 and 7 described above.

10 Multilayer chip inductor 11 Main body 12 Ceramic layer 14 Internal electrode layer 20 External electrode 30 Mixing ratio determination device 31 Input unit 32 Storage unit 33 1st calculation unit 34 2nd calculation unit 35 Display unit

Claims (16)

1. A method for producing a photosensitive composition containing a conductive powder at a predetermined compounding ratio.
   A process of measuring the particle size of the conductive powder used to obtain an actual measurement value;
   The measured value is a first correlation equation prepared in advance, and is a factor that fluctuates due to the particle size of the conductive powder and the light absorption or photocuring of the conductive film, and is used for the displacement of the particle size. A step of confirming the expected deviation value of the factor with respect to a predetermined target level by comparing with the first correlation formula with any of the factors that correlate and fluctuate;
   A second correlation equation prepared in advance, the factor in the first correlation equation, and any of the organic components contained in the photosensitive composition in which the variation in the compounding ratio correlates with the variation in the factor. A step of determining the blending ratio of the organic component so as to cancel the expected deviation value based on the second correlation equation with the component;
   A method for producing a photosensitive composition, which comprises.
2. The organic component is an organic component that adjusts at least one of the light absorption and photopolymerizability of the photosensitive composition.
   The method for producing a photosensitive composition according to claim 1.
3. The organic component is at least one of a photopolymerization initiator system, a light absorber, and a polymerization inhibitor.
   The method for producing a photosensitive composition according to claim 1.
4. The organic component is a photopolymerization initiator system.
   The method for producing a photosensitive composition according to claim 1.
5. Factors in the first correlation equation are the line width, film thickness, electrode cross-sectional area, curing shrinkage rate, or resistance value of the conductive film.
   The method for producing a photosensitive composition according to any one of claims 1 to 4.
6. The factor in the first correlation equation is the line width.
   The method for producing a photosensitive composition according to any one of claims 1 to 5.
7. The second correlation equation is represented by a linear function.
   The method for producing a photosensitive composition according to any one of claims 1 to 6.
8. The conductive powder contains silver-based particles.
   The method for producing a photosensitive composition according to any one of claims 1 to 7.
9. The conductive powder comprises core-shell particles containing a metal material to be a core and a ceramic material covering at least a part of the surface of the core.
   The method for producing a photosensitive composition according to any one of claims 1 to 8.
10. The photosensitive composition is used for forming electrodes.
    The method for producing a photosensitive composition according to any one of claims 1 to 9.
11. The photosensitive composition obtained by the production method according to any one of claims 1 to 10 is applied onto a substrate, photocured and etched, and then fired to obtain the photosensitive composition. A method for manufacturing an electronic component, further comprising a step of forming a conductive layer made of a fired body of.
12. A compounding ratio determining device that determines the compounding ratio of an organic component to a photosensitive composition containing a conductive powder at a predetermined compounding ratio.
    An input unit that accepts user input and inputs the type of conductive powder to be used and the measured value of particle size,
    It is a first correlation equation prepared in advance, and is a factor that fluctuates due to the particle size of the conductive powder and the light absorption or photocuring of the conductive film, and fluctuates in correlation with the displacement of the particle size. The first correlation equation with any of the factors and the second correlation equation prepared in advance, the factors in the first correlation equation and the organic components contained in the photosensitive composition, which are the blending ratios. A storage unit that stores a second correlation equation with any organic component whose fluctuation correlates with the fluctuation of the factor.
    Based on the first correlation equation, the first calculation unit that calculates the expected deviation value of the factor in the first correlation equation with respect to the predetermined target level from the actually measured value input to the input unit.
    Based on the second correlation equation, the second calculation unit that calculates the compounding ratio of the organic component in the second correlation equation that cancels the expected deviation value, and
    A compounding ratio determining device including.
13. Factors in the first correlation equation are the line width, film thickness, electrode cross-sectional area, curing shrinkage rate, or resistance value of the conductive film.
    The compounding ratio determining device according to claim 12.
14. A computer program configured to operate the computer as the compounding ratio determining device according to claim 12 or 13.
15. An electronic component comprising a conductive layer made of a fired body of a photosensitive composition obtained by the production method according to any one of claims 1 to 10.
16. A paste-like photosensitive composition in which the photosensitive composition obtained by the production method according to any one of claims 1 to 10 contains an organic dispersion medium.

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