Dielectric ceramic composition, molded body, and electronic component

Abstract

This dielectric ceramic composition contains forsterite as a main component and a glass component as a sub-component. The glass component contains lithium, calcium, barium, and silicon, and is contained in an amount of 12 parts by weight or more with respect to 100 parts by weight of the main component.

Description

Dielectric ceramic composition, molded body and electronic component

[0001] The present disclosure relates to a dielectric ceramic composition, a molded body, and an electronic component using the same.

[0002] Devices equipped with high-frequency circuits are known. For example, such devices are mobile phones. The high-frequency circuits are equipped with filters. Dielectric filters are widely used as such filters. Dielectric filters are filters that use laminated dielectric ceramics. Such dielectric ceramics are required to be suitable for use in high-frequency bands of several GHz.

[0003] A method for manufacturing a dielectric filter includes, for example, the following steps: First, a conductive paste is applied to each of a plurality of molded bodies made from ceramic powder that constitutes the dielectric. An electrode pattern (conductive paste layer) is formed from the applied conductive paste. Next, the plurality of molded bodies with the electrode patterns formed thereon are stacked to form a laminate, and the laminate is then fired. In this way, the conductive paste layer and the plurality of molded bodies are fired simultaneously, resulting in densification. The sintering temperature of the molded bodies in this manufacturing method needs to be lower than the melting point of the conductive material (metal material) contained in the conductive paste.

[0004] Dielectric ceramic compositions with better properties are desired.

[0005] The present invention aims to solve the above-mentioned problems.

[0006] A first aspect of the present invention is a dielectric ceramic composition containing forsterite as a main component and a glass component as a subcomponent, wherein the glass component contains lithium, calcium, barium, and silicon, and 12 parts by weight or more of the glass component is added to 100 parts by weight of the main component.

[0007] A second aspect of the present invention is a molded body having the dielectric ceramic composition.

[0008] A third aspect of the present invention is an electronic component having the molded article.

[0009] According to the present invention, a dielectric ceramic composition having better properties is provided.

[0010] FIG. 1 is a side view showing a portion of a side surface of an electronic component according to an embodiment. FIG. 2 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 3 is a graph showing the relationship between the glass addition amount and the fQ value determined based on Examples 1 to 8 and Comparative Examples 1 to 5. FIG. 4 is a graph showing the relationship between the glass addition amount and strength determined based on Examples 1 to 8 and Comparative Examples 1 to 5. FIG. 5 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 6 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 7 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 8 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 9 is a table showing experimental results of multiple examples. FIG. 10 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. FIG. 11 is a table for comparing experimental results of multiple examples with experimental results of multiple comparative examples. Fig. 12 is a table for comparing experimental results of a plurality of Examples with experimental results of a plurality of Comparative Examples. Fig. 13 is a table for comparing experimental results of a plurality of Examples with experimental results of a plurality of Comparative Examples. Fig. 14 is a table for comparing experimental results of a plurality of Examples with experimental results of a plurality of Comparative Examples. Fig. 15 is a table for comparing experimental results of a plurality of Examples with experimental results of a plurality of Comparative Examples.

[0011] Japanese Patent Application Laid-Open Publication No. 2000-211969 discloses a porcelain (dielectric porcelain) in which various glasses are added to a Ba-Al-Si-O system. According to Japanese Patent Application Laid-Open Publication No. 2000-211969, the sintering temperature of the porcelain is 1000°C or less, which is a relatively low temperature. However, the flexural strength of the porcelain disclosed in Japanese Patent Application Laid-Open Publication No. 2000-211969 is 270 MPa or less, making it unsuitable for application to substrates and the like that require high strength.

[0012] In addition, according to Japanese Patent Application Laid-Open No. 2021-155235 and Japanese Patent Application Laid-Open No. 2006-335633, the main component forsterite (Mg ２ SiO ４ By adjusting the composition of the additives (glass), the subcomponents, and the glass additive, a dielectric ceramic composition having a relatively high Q value and bending strength can be obtained. However, the dielectric constant of the dielectric ceramic composition disclosed in JP 2021-155235 A, JP 2006-335633 A, etc. is increased by the inclusion of the additive (glass) in the dielectric ceramic composition, and exceeds a dielectric constant of 9.

[0013] Based on the above preliminary explanation, one embodiment will be described below.

[0014] In the following description, the "dielectric constant" (relative permittivity, εr) was measured using a test piece made of a sintered body of the dielectric ceramic composition described below as a test object. The measurement of the dielectric constant was carried out by a both-ends short-circuited dielectric resonator method based on "Test methods for dielectric properties of microwave fine ceramics" (JIS-R-1627).

[0015] The "fQ value" in the following description was derived based on the dielectric loss tangent (tanδ) of the test piece obtained by the above-mentioned short-circuited dielectric resonator method using the above-mentioned test piece as the test object. More specifically, the fQ value of the test piece was derived as the product of the Q value (quality factor), which is the reciprocal of the dielectric loss tangent of the test piece, and the resonant frequency (unit: GHz) of the test piece.

[0016] The "temperature characteristic" (Tf) in the following description can be expressed as the rate of change (ppm / °C) in the resonant frequency of the dielectric ceramic composition due to temperature change. The temperature characteristic was derived based on the change in the resonant frequency of the test piece obtained by the above-mentioned short-circuited dielectric resonator method using the above-mentioned test piece as the test subject. The temperature change was performed in the range of 0°C to 85°C, with 20°C as the reference.

[0017] In the following description, "strength" was measured by stacking multiple ceramic sheets made of a sintered body of a dielectric ceramic composition to form a laminate (test piece) and performing a three-point bending strength test on the test piece. For this three-point bending strength test, the dimensions of the test piece were 30 mm x 2.0 mm. Furthermore, in the following description, "acid resistance" was evaluated based on the erosion distance measured by polishing the cross section of the test piece after immersing it in each of two types of acid solutions for three hours. The test piece used for acid resistance was a laminate (thickness: 0.6 mm, length: 1.6 mm, width: 0.8 mm) of multiple ceramic sheets made of a sintered body of a dielectric ceramic composition. One of the two types of acid solutions was an acid solution (temperature: 55°C, pH: 4.5) mainly composed of nickel sulfamate. The other of the two types of acid solutions was an acid solution (temperature: 35°C, pH: 4.5) mainly composed of tin methanesulfonate. The erosion distance was measured using a scanning electron microscope.

[0018] FIG. 1 is a side view showing a portion of a side surface of an electronic component 10 according to one embodiment.

[0019] The electronic component 10 is, for example, a filter. For more detailed information about the configuration of a filter, see, for example, Japanese Patent Application Laid-Open No. 2023-125226. The electronic component 10 is not limited to a filter. The electronic component 10 may also be, for example, a capacitor. As shown in FIG. 1 , the electronic component (electronic device) 10 has a plurality of sintered bodies 14 and a conductor 12. The plurality of sintered bodies 14 are stacked. Although FIG. 1 shows three stacked sintered bodies 14, one or more sintered bodies 14 (not shown) are stacked above the three sintered bodies 14. The sintered body 14 is a compact 16 of a sintered dielectric ceramic composition. That is, the sintered body 14 is obtained by sintering the compact 16 obtained by molding the dielectric ceramic composition according to this embodiment. A more detailed description of the dielectric ceramic composition will be provided later. The electronic component 10 can be manufactured, for example, by integrally firing the above-described compact 16 and the conductor 12. More specifically, openings for embedding the conductors 12 are formed by laser processing in a compact 16 containing ceramic powder made of a dielectric ceramic composition, and the paste-like conductors 12 are embedded in the openings, followed by firing. This allows the electronic component 10 to be manufactured. The conductors 12 may include, but are not limited to, via electrodes 121 and flat plate electrodes 122.

[0020] As described above, the dielectric ceramic composition can be used as a material for the electronic component 10. The dielectric ceramic composition is, for example, a granular material (powder, powder). The dielectric ceramic composition contains a main component and a subcomponent.

[0021] The main component is forsterite (Mg ２ SiO ４ The main component is barium titanate (BaTiO ３ ) and strontium titanate (SrTiO ３ ) and calcium titanate (CaTiO ３ ) and the like. This can improve the temperature characteristics of the dielectric ceramic composition.

[0022] However, if the content of barium titanate in the main component is too high, the fQ value of the dielectric ceramic composition will be excessively reduced. In light of this, the content of barium titanate in the main component is preferably 7 mol% or less. This prevents the fQ value from being excessively reduced.

[0023] Furthermore, if the content of strontium titanate in the main component is too high, the dielectric constant of the dielectric ceramic composition increases excessively. In light of this, the content of strontium titanate in the main component is preferably 13 mol% or less. This prevents the dielectric constant from increasing excessively.

[0024] Similarly, if the content of calcium titanate in the main component is too high, the dielectric constant of the dielectric ceramic composition will increase excessively. In light of this, the content of calcium titanate in the main component is preferably 17 mol% or less. This prevents the dielectric constant from increasing excessively.

[0025] The secondary components include a glass component (glass). The glass component is added to the primary component as an additive. The glass component includes a first glass component and a second glass component, which will be described below.

[0026] The first glass component according to this embodiment contains lithium (Li). In the following description, the content of lithium in the first glass component is also referred to as the Li content. The Li content is determined by the ratio of lithium to lithium oxide (Li ２ The Li content is 6 wt % or more and 18 wt % or less.

[0027] If the Li content is too low, the various components contained in the glass component may not melt, and a uniform glass molded body may not be obtained overall. In other words, if the Li content is too low, there is a relatively high risk that a good glass molded body will not be obtained. In this regard, a Li content of 6 wt% or more makes it easier to obtain a good glass molded body. Furthermore, a Li content of 6 wt% or more makes it easier to keep the sintering temperature of the dielectric ceramic composition at 950°C or less. This makes it possible to use silver as the conductor 12 when manufacturing an electronic component 10 having a dielectric ceramic composition and a conductor 12 by firing. That is, the melting point of silver is approximately 960°C. If the sintering temperature of the dielectric ceramic composition is higher than 960°C, silver melts during sintering, making it difficult to manufacture an electronic component 10 having silver as the conductor 12. In this regard, according to this embodiment, the dielectric ceramic composition can be sintered without melting silver. Copper may be used as the conductor 12. The melting point of copper is approximately 1085°C. Therefore, by suppressing the sintering temperature of the dielectric ceramic composition to 950°C or less, when an electronic component 10 having copper as the conductor 12 is manufactured by firing, the dielectric ceramic composition can be sintered without melting the copper. As mentioned above, the sintering temperature of the dielectric ceramic composition is preferably 950°C or less, but is more preferably 920°C or less. When the sintering temperature of the dielectric ceramic composition is 920°C or less, the risk of silver, copper, etc. melting is further reduced.

[0028] By setting the Li content to 18 wt % or less, a sintered body 14 having a good fQ value can be obtained. In this embodiment, a good fQ value is 15,000 or more.

[0029] The first glass component contains calcium (Ca). In the following description, the calcium content in the first glass component is also referred to as the Ca content. The Ca content can be expressed as the calcium oxide (CaO) equivalent content of calcium in the first glass component. The Ca content is 2 wt% or more and 9 wt% or less. A Ca content of 2 wt% or more suppresses a decrease in the fQ value. A Ca content of 9 wt% or less suppresses an increase in the dielectric constant of the sintered body 14. In this embodiment, a desirable dielectric constant is 9.0 or less. The lower the dielectric constant of the sintered body 14, the more preferable. For example, a dielectric constant of 8.5 or less is more preferable.

[0030] The first glass component contains barium (Ba). In the following description, the content of barium in the first glass component is also referred to as the Ba content. The Ba content can be expressed as the content of barium in the first glass component converted to barium oxide (BaO). The Ba content is 6 wt% or more and 20 wt% or less. A Ba content of 6 wt% or more suppresses a decrease in the fQ value. A Ba content of 20 wt% or less suppresses an increase in the dielectric constant.

[0031] The first glass component may further contain strontium (Sr). The first glass component may not contain strontium. In the following description, the strontium content in the first glass component is also referred to as the Sr content. The Sr content may be expressed as the content of strontium in the first glass component converted to strontium oxide (SrO). The Sr content is 0 wt% or more and 7 wt% or less. By having the Sr content be 7 wt% or less, an increase in the dielectric constant is suppressed.

[0032] The first glass component contains silicon (Si). In the following description, the content of silicon in the first glass component is also referred to as the Si content. The Si content is determined by the ratio of silicon dioxide (SiO ２The Si content is 50 wt % or more and 75 wt % or less. Silicon constitutes the remainder of the glass component excluding lithium, calcium, barium, and strontium. The remainder may be entirely composed of silicon, but is not limited to this. For example, the glass component may contain less than 1 wt % of alumina (Al ２ O ３ ) may further be contained. If the Si content is excessive, the various components contained in the glass component may not melt, and a uniform glass molded body may not be obtained as a whole. In other words, if the Si content is excessive, there is a relatively high risk that a good glass molded body may not be obtained. In this regard, if the Si content is 75 wt % or less, a good glass molded body can be easily obtained.

[0033] Calcium (Ca), barium (Ba), and strontium (Sr) belong to the alkaline earth metals (alkaline earth elements). Hereinafter, the total content of alkaline earth compounds contained in the glass components is also referred to as the total alkaline earth metal content. That is, the total alkaline earth metal content in this embodiment is the sum of the Ca content, the Ba content, and the Sr content. The total alkaline earth metal content affects the amount of change in dielectric constant. The amount of change in dielectric constant is the increase in dielectric constant corresponding to an increase of 1 part by weight of the added amount of the glass components. The increase in the total alkaline earth metal content increases the rate of increase in dielectric constant. The rate of increase in dielectric constant can be adjusted by adjusting the total alkaline earth metal content. That is, the increase in dielectric constant can be suppressed by suppressing the amount of change in dielectric constant. The total alkaline earth metal content is preferably 32 wt% or less. The total alkaline earth metal content is more preferably 25 wt% or less. The total alkaline earth metal content is more preferably 22 wt% or less. The total alkaline earth metal content is more preferably 19 wt% or less. The total amount of alkaline earth elements is more preferably 11 wt % or less.

[0034] The second glass component contains boron-based glass. This can reduce the sintering temperature of the molded body 16 (dielectric ceramic composition). The content of the second glass component in the dielectric ceramic composition is 3 parts by weight or less relative to 100 parts by weight of the main component. This can suppress deterioration of the acid resistance of the dielectric ceramic composition due to the inclusion of boron-based glass. The second glass component does not have to be included in the dielectric ceramic composition. When the dielectric ceramic composition contains the second glass component, it is more preferable that the content of the second glass component in the dielectric ceramic composition is 2 parts by weight or less relative to 100 parts by weight of the main component. This can further suppress deterioration of the acid resistance of the dielectric ceramic composition due to the inclusion of boron-based glass. As described above, acid resistance is evaluated based on the erosion distance described above. The allowable erosion distance in this embodiment is 3 μm or less.

[0035] The above-mentioned glass component is added in a content of 12 to 25 parts by weight relative to 100 parts by weight of the main component. For example, when the content of the second glass component is 2 parts by weight relative to 100 parts by weight of the main component, the content of the first glass component is 10 to 23 parts by weight relative to 100 parts by weight of the main component. When the amount of glass component added is 12 parts by weight or more relative to 100 parts by weight of the main component, a sintered body 14 having sufficient strength is obtained. In this embodiment, a guideline for sufficient strength is 270 MPa or more. The content of the second glass component can be appropriately adjusted within a range in which the dielectric constant of the sintered body 14 is 9.0 or less and the strength of the sintered body 14 is 270 MPa or more.

[0036] By adding 25 parts by weight or less of the glass component relative to 100 parts by weight of the main component, a decrease in the fQ value of the sintered body 14 and a deterioration in the temperature characteristics of the sintered body 14 are suppressed. In this embodiment, the temperature characteristics are determined to be good when the absolute value of the temperature characteristics of the sintered body 14 is 60 ppm / °C or less. It is more preferable that the absolute value of the temperature characteristics of the sintered body 14 is 30 ppm / °C or less.

[0037] The dielectric ceramic composition may further contain a copper compound, such as, but not limited to, copper oxide (CuO). For example, the copper compound may be a carbonate, a nitrate, an oxalate, a hydroxide, a sulfide, an organometallic compound, or the like.

[0038] When a copper compound is contained in the dielectric ceramic composition, the copper compound is contained in a content of more than 0 parts by weight and less than 7 parts by weight in terms of copper oxide (CuO) relative to 100 parts by weight of the main component. By containing a copper compound in the dielectric ceramic composition, the sintering temperature of the dielectric ceramic composition can be lowered. By having the content of the copper compound in the dielectric ceramic composition be less than 7 parts by weight in terms of copper oxide, a decrease in the fQ value is suppressed.

[0039] The above-mentioned sintered body 14 (the molded body 16 of the dielectric ceramic composition) is manufactured based on the manufacturing method described below, for example. This manufacturing method includes a first step, a second step, a third step, and a fourth step.

[0040] In the first step (main component preparation step), the main component is prepared. More specifically, the main component is prepared according to the following steps (1) to (3): (1) Mg oxide and Si oxide are prepared as starting materials. The starting materials may be compounds from which Mg oxide and Si oxide can be obtained by heat treatment. (2) A mixed powder containing the starting materials is prepared. Hereinafter, this mixed powder is referred to as the first mixed powder. The first mixed powder is obtained by wet-pulverizing the starting materials. The molar ratio of Mg element to Si element in the first mixed powder is 2:1. (3) The first mixed powder is calcined, and the calcined first mixed powder is pulverized. This results in a main component powder. The main component powder is a powder of the main component (forsterite). The first mixed powder is calcined at 1000°C to 1200°C for 2 to 3 hours, but is not limited to this.

[0041] The first step may include, as appropriate, obtaining powders such as barium titanate, strontium titanate, and calcium titanate. By appropriately changing the starting materials described above to calcium carbonate, barium carbonate, carbonates of strontium carbonate, titanium oxide, and the like, powders such as barium titanate, strontium titanate, and calcium titanate can be obtained. Powders such as barium titanate, strontium titanate, and calcium titanate are included in the main component powder along with the forsterite powder described above. In this case, the molar ratio of Ba to Ti is 1:1. The molar ratios of Sr to Ti and Ca to Ti are also each 1:1.

[0042] In the second step (subcomponent preparation step), a glass component (first glass component) is prepared as a subcomponent. More specifically, the glass component is prepared according to the following steps (4) to (7): (4) SiO ２ And Li ２ CO ３ and CaCO ３ and BaCO ３ and SrCO ３ and are mixed in the desired content to obtain a mixed powder. Hereinafter, this mixed powder is referred to as the second mixed powder. (5) The second mixed powder is heated to melt, and then cooled to obtain a glass molded body. Heating is performed using heat of, for example, 1200°C to 1500°C. (6) The glass molded body is pulverized and then classified. (7) The classified glass molded body (powder) is pulverized. This yields a minor component powder. The minor component powder is a powder of the minor component (glass component). Note that the materials mixed in the above-mentioned (4) are converted into SiO by heat treatment. ２ And Li ２ The second glass component may be a compound capable of obtaining SiO, CaO, BaO, and SrO. In the second step, the above-mentioned second glass component may be further prepared as an additional subcomponent. The second glass component is prepared, for example, according to the following steps (A) to (D): (A) SiO ２ and BaCO ３ And B ２ O ３and ZnO are mixed in desired amounts to obtain a mixed powder. (B) The obtained mixed powder is heated to melt and then cooled to obtain a glass molded body. Heating is performed using heat of, for example, 1200°C to 1500°C. (C) The obtained glass molded body is crushed and then classified. (D) The classified glass molded body (powder) is crushed. As a result, SiO ２ , BaO, and B ２ O ３ The resulting powder is a boron-based glass (second glass component) containing SiO and ZnO. ２ , BaO, and B ２ O ３ and ZnO may be obtained.

[0043] In the third step (sample production step), the subcomponent powder obtained in the second step is added to the main component powder obtained in the first step. This results in a powder of the dielectric ceramic composition according to this embodiment. The glass component is added in an amount of 12 to 25 parts by weight per 100 parts by weight of the main component. Hereinafter, the obtained powder of the dielectric ceramic composition will be referred to as the sample powder. The sample powder may further contain a copper compound (powder).

[0044] In the fourth step (sintering step), the sample powder is sintered to obtain a sintered body 14 of the dielectric ceramic composition. More specifically, the sample powder is sintered according to the following steps (8) to (11). (8) A molding aid is added to the sample powder, and the sample powder is molded into a sheet using a predetermined molding method. This results in a ceramic sheet. The molding aid is, for example, an organic binder. The predetermined molding method is, for example, press molding, doctor blade method, etc. (9) A plurality of ceramic sheets are stacked to form a laminate. The laminate may be subjected to press working. (10) The laminate is cut to the desired dimensions to obtain a molded body 16 of the dielectric ceramic composition. (11) The molded body 16 is fired to obtain a sintered body 14. The molded body 16 is heated, for example, using heat of 850°C to 950°C for two hours.

[0045] Hereinafter, the characteristics of the dielectric ceramic composition according to one embodiment will be described while comparing an example with a comparative example.

[0046] 2 is a table for comparing the experimental results of a number of examples with the experimental results of a number of comparative examples. Examples 1 to 8 and comparative examples 1 to 5 are shown in FIG.

[0047] The "Main Component" column in FIG. 2 shows the main components of the dielectric ceramic composition. The "Glass Composition" column in FIG. 2 shows the contents (wt%) of various components contained in the glass component. More specifically, the "SiO ２ The column "Li" in FIG. 2 shows the Si content. ２ The "O" column in FIG. 2 shows the Li content described above. The "BaO" column in FIG. 2 shows the Ba content described above. The "CaO" column in FIG. 2 shows the Ca content described above. The "SrO" column in FIG. 2 shows the Sr content described above. The "Glass Addition Amount" column in FIG. 2 shows the amount (parts by weight) of the glass component added relative to 100 parts by weight of the main component. The "Vitrification" column in FIG. 2 shows whether or not a good glass molded body was obtained in the second step described above. The "OK" mark in the "Vitrification" column indicates that a good glass molded body was obtained. The "NG" mark in the "Vitrification" column indicates that a good glass molded body was not obtained. In other words, the "NG" mark in the "Vitrification" column indicates that the various components contained in the glass component were not melted in (7) of the second step described above, and a uniform glass molded body as a whole was not obtained. The "Sintering Temperature" column in FIG. 2 shows the temperature at which the laminate is sintered in the fourth step described above.

[0048] The "Characteristics" column in Figure 2 shows various characteristics (εr, fQ value, Tf, strength) measured by the above-mentioned measurement method. εr (dielectric constant), fQ value, and Tf (temperature characteristic) were measured using a test piece (sintered compact) with a diameter of 16 mm and a height of 8 mm. Strength measurements were performed 30 times on a test piece (sintered compact) with a length of 30 mm, a width of 2.0 mm, and a height of 1.8 mm, and the average value of the 30 strength measurements (three-point bending strength) was recorded as the strength of the test piece.

[0049] Fig. 3 is a graph showing the relationship between the glass addition amount and the fQ value determined based on Examples 1 to 8 and Comparative Examples 1 to 5. Fig. 4 is a graph showing the relationship between the glass addition amount and the strength determined based on Examples 1 to 8 and Comparative Examples 1 to 5. Note that, due to the limitations of the range of the vertical axis of the graphs, the plot of the numerical values ​​for Comparative Example 1 in Figs. 3 and 4 has been omitted.

[0050] Examples 1 to 8 and Comparative Examples 1 to 5 shared the same glass composition but varied in the amount of glass added. In Examples 1 to 8, the amount of glass added relative to 100 parts by weight of the main component was within the range of 12 parts by weight to 25 parts by weight, whereas in Comparative Examples 1 to 5, the amount of glass added was outside this range. As a result, as shown in FIGS. 2 to 4 , Examples 1 to 8 all exhibited favorable sintering temperatures, dielectric constants, fQ values, temperature characteristics, and strength. In contrast, in Comparative Examples 1 to 5, at least one of the sintering temperatures, dielectric constants, fQ values, temperature characteristics, and strength did not fall within the favorable ranges. For example, in Comparative Example 4, the fQ value did not reach 15,000. Furthermore, in Comparative Example 4, the absolute value of the temperature characteristics exceeded 60.

[0051] 2 to 4, it was confirmed that even if the glass composition is constant, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength change depending on the amount of glass added. Also, it was confirmed from Figures 2 to 4 that a good dielectric ceramic composition is easily obtained if the amount of glass added is within the range of 12 parts by weight to 25 parts by weight per 100 parts by weight of the main component.

[0052] Fig. 5 is a table for comparing the experimental results of several examples with the experimental results of several comparative examples. Examples 9 to 12 and comparative examples 6 to 9 are shown in Fig. 5. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 5.

[0053] 5 shows a "Total Amount of Alkaline Earth Elements" column. As described above, the total amount of alkaline earth elements is the total amount of alkaline earth compounds contained in the glass components. That is, the "Total Amount of Alkaline Earth Elements" column in FIG. 5 shows the sum (wt %) of the Ca content shown in the "CaO" column, the Ba content shown in the "BaO" column, and the Sr content shown in the "SrO" column. The information shown in the other columns in FIG. 5 is the same as that in FIG. 2.

[0054] In Examples 9 to 12 and Comparative Examples 6 to 9, the glass addition amount was the same but the Li content was different. In Examples 9 to 12, the Li content was within the range of 6 wt % to 18 wt %, but in Comparative Examples 6 to 9, the Li content was outside this range. As a result, as shown in FIG. 5 , in Examples 9 to 12, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In contrast, in Comparative Examples 6 and 7, where the Li content was relatively low, the minor components were not well vitrified, and the sintering temperature exceeded 1,000°C. Furthermore, in Comparative Examples 6 and 7, the absolute value of the temperature characteristics exceeded 60. In Comparative Examples 8 and 9, where the Li content was relatively high, the fQ value did not reach 15,000.

[0055] 5, it was confirmed that the sintering temperature and fQ value change relatively significantly depending on the Li content even when the amount of glass added is constant. Also, it was confirmed from Fig. 5 that a good dielectric ceramic composition can be obtained when the Li content in the glass component is 6 wt% or more and 18 wt% or less.

[0056] Fig. 6 is a table for comparing the experimental results of several examples with the experimental results of several comparative examples. Examples 13 to 16 and comparative examples 10 and 11 are shown in Fig. 6. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 6. The table format of Fig. 6 is similar to that of Fig. 5.

[0057] Examples 13 to 16 and Comparative Examples 10 and 11 had the same glass additive amount but different Ca contents. In Examples 13 to 16, the Ca content was within the range of 2 wt % to 9 wt %, but in Comparative Examples 10 and 11, the Ca content was outside this range. As a result, as shown in FIG. 6 , Examples 13 to 16 were good in terms of sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength. In contrast, in Comparative Example 10, where the Ca content was relatively low, the fQ value did not reach 15,000. In Comparative Example 11, where the Ca content was relatively high, the dielectric constant exceeded 9.0.

[0058] 6, it was confirmed that even if the amount of glass added was constant, the fQ value and the dielectric constant changed relatively greatly depending on the Ca content. Also, it was confirmed from Fig. 6 that a good dielectric ceramic composition could be obtained if the Ca content was 2 wt% or more and 9 wt% or less.

[0059] Fig. 7 is a table for comparing the experimental results of several examples and the experimental results of several comparative examples. Examples 17 to 23 and comparative examples 12 to 15 are shown in Fig. 7. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 7. The table format of Fig. 7 is similar to that of Fig. 5.

[0060] Examples 17 to 23 and Comparative Examples 12 to 15 had the same glass additive amount but different Ba contents. In Examples 17 to 23, the Ba content was within the range of 6 wt % to 20 wt %, but in Comparative Examples 12 to 15, the Ba content was outside this range. As a result, as shown in FIG. 7 , Examples 17 to 23 exhibited excellent sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength. In contrast, in Comparative Examples 12 to 14, in which the Ba content was relatively low, the fQ value did not reach 15,000. Furthermore, in Comparative Examples 12 and 13, the minor components were not well vitrified. Furthermore, in Comparative Example 15, in which the Ba content was relatively high, the dielectric constant exceeded 9.0.

[0061] 7, it was confirmed that even when the amount of glass added was constant, the fQ value and the dielectric constant changed relatively greatly depending on the Ba content. Also, it was confirmed from Fig. 7 that a good dielectric ceramic composition was easily obtained when the Ba content was 6 wt% or more and 20 wt% or less.

[0062] Fig. 8 is a table for comparing the experimental results of several examples with the experimental results of several comparative examples. Examples 24 to 29 and comparative examples 16 to 18 are shown in Fig. 8. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 8. The table format of Fig. 8 is similar to that of Fig. 5.

[0063] In Example 3, Examples 24 to 27, and Comparative Example 16, the amount of glass added was the same but the Sr content was different. In Example 3 and Examples 24 to 27, the Sr content was within the range of 0 wt % or more and 7 wt % or less, but in Comparative Example 16, the Sr content was outside this range. As a result, as shown in Figure 8, in Example 3 and Examples 24 to 27, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In contrast, in Comparative Example 16, the dielectric constant exceeded 9.0.

[0064] 8, it was confirmed that the dielectric constant changes relatively greatly depending on the Sr content even when the amount of glass added is constant. Also, it was confirmed from Fig. 8 that a good dielectric ceramic composition can be obtained when the Sr content is 0 wt% or more and 7 wt% or less.

[0065] 8, it was confirmed that good dielectric ceramic compositions were obtained in Examples 28 and 29. In contrast, it was confirmed that good dielectric ceramic compositions were not obtained in Comparative Examples 17 and 18. For example, in Comparative Example 17, the minor components were not vitrified well, and the sintering temperature reached 1000°C. In Comparative Example 18, the dielectric constant exceeded 9.0.

[0066] 9 is a table showing experimental results for several examples, Examples 30-34 are shown in FIG.

[0067] The "dielectric constant change" column in Fig. 9 shows the above-mentioned dielectric constant change. As described above, the dielectric constant change is the increase in dielectric constant corresponding to an increase of 1 part by weight of the added amount of the glass component. The information shown in the other columns in Fig. 9 is the same as that in Fig. 5.

[0068] The total amount of alkaline earth elements was varied in Examples 30 to 34. More specifically, in Example 30, the total amount of alkaline earth elements was 11 wt %. In Example 31, the total amount of alkaline earth elements was 19 wt %. In Example 32, the total amount of alkaline earth elements was 22 wt %. In Example 33, the total amount of alkaline earth elements was 25 wt %. In Example 34, the total amount of alkaline earth elements was 32 wt %.

[0069] Although not shown, the dielectric constant when the glass content was 12 parts by weight (hereinafter referred to as the first dielectric constant), the dielectric constant when the glass content was 15 parts by weight (hereinafter referred to as the second dielectric constant), and the dielectric constant when the glass content was 25 parts by weight (hereinafter referred to as the third dielectric constant) were measured. The amount of change in dielectric constant for Example 30 was derived based on the first dielectric constant, second dielectric constant, and third dielectric constant measured in Example 30. The amount of change in dielectric constant for Example 31 was derived based on the first dielectric constant, second dielectric constant, and third dielectric constant measured in Example 31. The amount of change in dielectric constant for Example 32 was derived based on the first dielectric constant, second dielectric constant, and third dielectric constant measured in Example 32. The amount of change in dielectric constant for Example 33 was derived based on the first dielectric constant, second dielectric constant, and third dielectric constant measured in Example 33. The amount of change in dielectric constant according to Example 34 was derived based on the first dielectric constant, the second dielectric constant, and the third dielectric constant measured in Example 34.

[0070] The derived dielectric constant change (unit: %) is shown in the "Dielectric Constant Change" column in FIG. 9 . It was confirmed from FIG. 9 that the dielectric constant change increases as the total amount of alkaline earth elements increases. In other words, it was confirmed from FIG. 9 that the dielectric constant change decreases as the total amount of alkaline earth elements decreases. Furthermore, it was confirmed that if the total amount of alkaline earth elements is 32 wt % or less, the dielectric constant change can be suppressed to 29.6% or less. If the total amount of alkaline earth elements is 25 wt % or less, the dielectric constant change can be suppressed to 21.4% or less. If the total amount of alkaline earth elements is 22 wt % or less, the dielectric constant change can be suppressed to 13.8% or less. It was also confirmed that if the total amount of alkaline earth elements is 19 wt % or less, the dielectric constant change can be suppressed to 2.7% or less. It was also confirmed that if the total amount of alkaline earth elements is 11 wt % or less, the dielectric constant change can be suppressed to 1.2% or less.

[0071] Fig. 10 is a table for comparing the experimental results of several examples with the experimental results of several comparative examples. Examples 35 to 37 and Comparative Example 19 are shown in Fig. 10. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 10.

[0072] The "First Principal Component", "Second Principal Component", and "Third Principal Component" columns in FIG. 10 show the principal components. The "Principal Component Ratio" column in FIG. 10 shows the contents of various compounds that may be contained in the principal component in that principal component. More specifically, "1" in the "Principal Component Ratio" column shows the content of the compound shown in the "First Principal Component" column. "2" in the "Principal Component Ratio" column shows the content of the compound shown in the "Second Principal Component" column. "3" in the "Principal Component Ratio" column shows the content of the compound shown in the "Third Principal Component" column. The information shown in the other columns in FIG. 10 is similar to that in FIG. 2.

[0073] In Examples 35 to 37 and Comparative Example 19, the glass composition and the amount of glass added were the same, but the ratio of the main components was different.

[0074] In Examples 35 to 37 and Comparative Example 19, the first principal component was Mg ２ SiO ４ The second principal component is BaTiO ３In Examples 35 to 37, the second main component (BaTiO ３ In contrast, in Comparative Example 19, the content of the second main component (BaTiO ３ ) in the main component was deviated from the range. More specifically, in Comparative Example 19, the content of the second main component (BaTiO ３ ) in the main component was made to be more than 7 mol %. As a result, as shown in FIG. 10, in Examples 35 to 37, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In particular, the absolute value of the temperature characteristics of Examples 35 to 37 was good when the main component was Mg. ２ SiO ４ The absolute value of the temperature characteristic was smaller than that of Example 3 consisting only of Example 3. That is, the temperature characteristics of Examples 35 to 37 were better than that of Example 3. In contrast, in Comparative Example 19, the fQ value did not reach 15,000.

[0075] Fig. 11 is a table for comparing the experimental results of a number of examples with the experimental results of a number of comparative examples. Examples 38 to 43 and Comparative Example 20 are shown in Fig. 11. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 11. The table format of Fig. 11 is similar to that of Fig. 10.

[0076] In Examples 38 to 43 and Comparative Example 20, the first principal component was Mg ２ SiO ４ The second principal component is SrTiO ３ In Examples 38 to 43, the second main component (SrTiO ３ In contrast, in Comparative Example 20, the content of the second main component (SrTiO ３ ) in the main component was deviated from the range. More specifically, in Comparative Example 20, the content of the second main component (SrTiO ３) in the main component was made to be more than 13 mol%. As a result, as shown in FIG. 11, in Examples 38 to 43, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In particular, the temperature characteristics of Examples 38 to 43, like Examples 35 to 37, were better than the temperature characteristics of Example 3. In contrast, in Comparative Example 20, the dielectric constant exceeded 9.0.

[0077] Fig. 12 is a table for comparing the experimental results of a number of examples with the experimental results of a number of comparative examples. Examples 44 to 54 and Comparative Example 21 are shown in Fig. 12. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 12. The table format of Fig. 12 is similar to that of Fig. 10.

[0078] In Examples 44 to 51 and Comparative Example 21, the first principal component was Mg ２ SiO ４ The second principal component is CaTiO ３ In Examples 44 to 51, the second main component (CaTiO ３ In contrast, in Comparative Example 21, the content of the second main component (CaTiO ３ ) in the main component was deviated from the range. More specifically, in Comparative Example 21, the content of the second main component (CaTiO ３ ) in the main component was made to be more than 17 mol%. As a result, as shown in Figure 12, in Examples 44 to 51, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In particular, the temperature characteristics of Examples 44 to 51, like Examples 35 to 37, were better than the temperature characteristics of Example 3. In contrast, in Comparative Example 21, the dielectric constant exceeded 9.0.

[0079] In Examples 52 to 54, the first principal component was Mg ２ SiO ４ In Examples 52 to 54, the above-mentioned BaTiO ３ and SrTiO ３ and CaTiO ３Two of these were selected and included in the main components (the second and third main components). In Examples 52 to 54, different combinations of the main components (the second and third main components) were selected. More specifically, in Example 52, Mg ２ SiO ４ and BaTiO ３ and SrTiO ３ In Example 53, the main component was composed of Mg ２ SiO ４ and CaTiO ３ and BaTiO ３ In Example 54, the main component was composed of Mg ２ SiO ４ and CaTiO ３ and SrTiO ３ The main components were composed of the above. The contents of the second main component and the third main component were both 5 mol%. As a result, as shown in FIG. 12, in Examples 52 to 54, the sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength were all good. In particular, the absolute values ​​of the temperature characteristics of Examples 52 to 54 were smaller and better than those of Examples 35 to 37 described above.

[0080] 10 to 12, Mg ２ SiO ４ Not only does it contain BaTiO as the main component, ３ and SrTiO ３ and CaTiO ３ It was confirmed that the temperature characteristics were improved by further including at least one of the following in the main component. ３ It was confirmed that the content of SrTiO is preferably 7 mol % or less. ３ It was confirmed that the content of CaTiO is preferably 13 mol% or less. ３ It was confirmed that the content is preferably 17 mol % or less.

[0081] Fig. 13 is a table for comparing the experimental results of several examples and several comparative examples. Examples 55 to 57 and Comparative Example 22 are shown in Fig. 13. For comparison, Example 3, which is also shown in Fig. 2, is also shown in Fig. 13.

[0082] The "CuO content" column in Fig. 13 shows the content (parts by weight) of CuO relative to 100 parts by weight of the main component. The information shown in the other columns in Fig. 13 conforms to that in Fig. 2.

[0083] Examples 55-57 and Comparative Example 22 shared the same main component composition. Examples 55-57 and Comparative Example 22 also shared the same glass component composition. Furthermore, Examples 55-57 and Comparative Example 22 shared the same glass additive amount. Examples 55-57 and Comparative Example 22 differed in the copper compound content. In Examples 55-57, the copper compound content was within a range of more than 0 parts by weight and less than 7 parts by weight. In contrast, in Comparative Example 22, the copper compound content was outside this range. More specifically, in Comparative Example 22, the copper compound content was 7 parts by weight. As a result, as shown in FIG. 13 , Examples 55-57 were excellent in terms of sintering temperature, dielectric constant, fQ value, temperature characteristics, and strength. In particular, the sintering temperatures of Examples 55-57 were lower than those of Example 3, which did not contain a copper compound. That is, the sintering temperatures of Examples 55-57 were better than those of Example 3. In contrast, in Comparative Example 22, the fQ value did not reach 15,000.

[0084] 13, it was confirmed that the sintering temperature can be improved by adding copper oxide (copper compound) to the dielectric ceramic composition. It was also confirmed that a good dielectric ceramic composition can be obtained if the content of copper oxide is less than 7 parts by weight relative to 100 parts by weight of the main component.

[0085] 14 and 15 are tables for comparing the experimental results of several examples with the experimental results of several comparative examples. Examples 58 to 60 and comparative examples 23 and 24 are shown in FIGS. 14 and 15. For comparison, Example 1, which is also shown in FIG. 2, is also shown in FIGS. 14 and 15.

[0086] Examples 1, 58 to 60, and Comparative Examples 23 and 24 all had the same composition of the main components. On the other hand, Examples 1, 58 to 60, and Comparative Examples 23 and 24 had different amounts of added glass components. More specifically, Examples 1, 58 to 60, and Comparative Examples 23 and 24 had different amounts of added first glass components, i.e., the first glass added amount, and the second glass added amount, i.e., the second glass added amount. The first glass composition, which is the composition of the first glass component, is the same as the glass composition shown in FIG. 2. The second glass composition, which is the composition of the second glass component, is shown in FIGS. 14 and 15. As shown in FIGS. 14 and 15, the second glass component contained SiO ２ , BaO, and B ２ O ３ A boron-based glass containing ZnO was prepared. In Examples 1 and 58-60, the amount of the second glass added was within the range of 0 parts by weight or more and 3 parts by weight or less. In contrast, in Comparative Examples 23 and 24, the amount of the second glass added was outside this range. More specifically, in Comparative Examples 23 and 24, the amount of the second glass added was 4 parts by weight or more. As a result, as shown in Figures 14 and 15, Example 1 and Examples 58-60 all exhibited excellent sintering temperature, dielectric constant, fQ value, temperature characteristics, strength, and acid resistance. In particular, with regard to acid resistance, as shown in Figure 15, the erosion distances of Examples 1 and 58-60 were within the target range of 3 μm or less. In contrast, in Comparative Examples 23 and 24, the erosion distances were 4 μm or more.

[0087] 14 and 15 (particularly FIG. 15), it was confirmed that by suppressing the content of boron-based glass contained in the dielectric ceramic composition to 3 parts by weight or less, good acid resistance is imparted to the dielectric ceramic composition.

[0088] The following additional notes are provided regarding the above-described embodiments and examples.

[0089] (Appendix 1) The dielectric ceramic composition according to the present disclosure is a dielectric ceramic composition containing forsterite as a main component and a glass component as a secondary component, wherein the glass component contains lithium, calcium, barium, and silicon, and 12 parts by weight or more of the glass component is added to 100 parts by weight of the main component.

[0090] (Appendix 2) The dielectric ceramic composition according to appendix 1 may be a dielectric ceramic composition in which the amount of the glass component added is 25 parts by weight or less relative to 100 parts by weight of the main component.

[0091] (Appendix 3) The dielectric ceramic composition according to Appendix 1 may be a dielectric ceramic composition in which the content of lithium oxide in the glass component is 6 wt% or more and 18 wt% or less, the content of calcium oxide in the glass component is 2 wt% or more and 9 wt% or less, the content of barium oxide in the glass component is 6 wt% or more and 20 wt% or less, and the content of silicon dioxide in the glass component is 50 wt% or more and 75 wt% or less.

[0092] (Appendix 4) The dielectric ceramic composition according to appendix 3 may be a dielectric ceramic composition in which the total amount of alkaline earth elements, which is the content of alkaline earth elements in the glass component, is 32 wt% or less.

[0093] (Appendix 5) The dielectric ceramic composition according to appendix 4 may be a dielectric ceramic composition in which the total amount of alkaline earth elements is 25 wt% or less.

[0094] (Appendix 6) The dielectric ceramic composition according to appendix 5 may be a dielectric ceramic composition in which the total amount of alkaline earth elements is 22 wt% or less.

[0095] (Appendix 7) The dielectric ceramic composition according to appendix 6 may be a dielectric ceramic composition in which the total amount of alkaline earth elements is 19 wt% or less.

[0096] (Appendix 8) The dielectric ceramic composition according to any one of Appendices 1 to 7 may be a dielectric ceramic composition in which the main component further contains at least one of barium titanate, strontium titanate, and calcium titanate, and the content of barium titanate in the main component is 7 mol% or less, the content of strontium titanate in the main component is 13 mol% or less, and the content of calcium titanate in the main component is 17 mol% or less.

[0097] (Appendix 9) The dielectric ceramic composition according to any one of Appendices 1 to 7 may be a dielectric ceramic composition containing a copper compound in an amount of more than 0 parts by weight and less than 7 parts by weight in terms of copper oxide relative to the main component.

[0098] (Appendix 10) A compact (16) according to the present disclosure is a compact having the dielectric ceramic composition according to any one of Appendices 1 to 7.

[0099] (Appendix 11) The molded body according to Appendix 10 may be a sintered molded body having a relative dielectric constant of 9.0 or less, an fQ value, which is the product of the Q value and the resonant frequency, of 15,000 or more, and a three-point bending strength of 270 MPa or more.

[0100] (Appendix 12) The molded article according to appendix 11 may have a relative dielectric constant of 8.5 or less.

[0101] (Supplementary Note 13) An electronic component (10) according to the present disclosure is an electronic component having the molded article described in Supplementary Note 10.

[0102] (Supplementary Note 14) The electronic component according to Supplementary Note 13 may be an electronic component in which the conductor (12) containing silver is integrally fired with the molded body.

[0103] The present invention is not limited to the above disclosure, and various configurations can be adopted without departing from the gist of the present disclosure.

Claims

1. A dielectric ceramic composition containing forsterite as a main component and a glass component as a subcomponent, the glass component containing lithium, calcium, barium, and silicon, and 12 parts by weight or more of the glass component is added to 100 parts by weight of the main component.

2. A dielectric ceramic composition according to claim 1, wherein the amount of said glass component added is 25 parts by weight or less per 100 parts by weight of said main component.

3. A dielectric ceramic composition as claimed in claim 1, wherein the lithium oxide content in the glass component is 6 wt% or more and 18 wt% or less, the calcium oxide content in the glass component is 2 wt% or more and 9 wt% or less, the barium oxide content in the glass component is 6 wt% or more and 20 wt% or less, and the silicon dioxide content in the glass component is 50 wt% or more and 75 wt% or less.

4. A dielectric ceramic composition according to claim 3, wherein the total amount of alkaline earth elements, which is the content of alkaline earth elements in the glass component, is 32 wt % or less.

5. A dielectric ceramic composition according to claim 4, wherein the total amount of said alkaline earth elements is 25 wt % or less.

6. A dielectric ceramic composition according to claim 5, wherein the total amount of said alkaline earth elements is 22 wt % or less.

7. A dielectric ceramic composition according to claim 6, wherein the total amount of said alkaline earth elements is 19 wt % or less.

8. A dielectric ceramic composition according to any one of claims 1 to 7, wherein the main component further contains at least one of barium titanate, strontium titanate, and calcium titanate, the content of the barium titanate in the main component is 7 mol % or less, the content of the strontium titanate in the main component is 13 mol % or less, and the content of the calcium titanate in the main component is 17 mol % or less.

9. A dielectric ceramic composition according to any one of claims 1 to 7, wherein a copper compound is contained in an amount of more than 0 parts by weight and less than 7 parts by weight, calculated as copper oxide, relative to the main component.

10. A molded body comprising the dielectric ceramic composition according to any one of claims 1 to 7.

11. The molded body according to claim 10, which is sintered, has a relative dielectric constant of 9.0 or less, an fQ value, which is the product of the Q value and the resonant frequency, of 15,000 or more, and a three-point bending strength of 270 MPa or more.

12. The molded article according to claim 11, wherein the dielectric constant is 8.5 or less.

13. An electronic component comprising the molded article according to claim 10.

14. An electronic component according to claim 13, wherein a conductor containing silver is integrally fired with said molded body.

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