Manufacturing method for stacked electronic components and stacked electronic components

Abstract

The present invention provides a method for manufacturing a multilayer electronic component that reduces dielectric breakdown of the ceramic layer, and a multilayer electronic component. [Solution] In the method for manufacturing a stacked electronic component 1, the stacked body 7 is produced by firing a stacked body, which consists of ceramic green sheets that form a ceramic layer 11 on which internal electrodes 13 having a composition of 60% or more by mass of Cu are printed, by irradiating the stacked body with millimeter waves. The frequency of the millimeter waves is between 24 GHz and 28 GHz, which reduces the diffusion of Cu into the ceramic layer and improves the breakdown voltage (BDV).

Description

[Technical Field]

[0001] This disclosure relates to a method for manufacturing multilayer electronic components such as multilayer ceramic capacitors, and to multilayer electronic components themselves. [Background technology]

[0002] Multilayer ceramic capacitors have a laminate in which ceramic layers and internal electrodes are alternately stacked. The laminate is manufactured, for example, by stacking and firing green sheets on which the internal electrodes are printed. Known firing methods include applying heat to the laminate using a firing furnace and irradiating the laminate with microwaves (see, for example, Patent Document 1 below).

[0003] Patent Document 1 lists several examples of the types of metals included in the conductive layer, including copper (Cu). Examples of microwave frequencies given are 5 GHz to 28 GHz. Examples of oxygen partial pressure during firing are 0.2 atm and 3 × 10⁻⁶. -3 ATM and 3x10 -8 Atm is mentioned. It is disclosed that a temperature of 900°C to 1200°C can be maintained for 0.5 to 10 minutes by heating with microwaves. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2002-289457 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] For example, there is a need for a manufacturing method for multilayer electronic components and multilayer electronic components in which the diffusion of Cu into the ceramic layer is reduced. [Means for solving the problem]

[0006] A method for manufacturing a multilayer electronic component according to an aspect of the present disclosure irradiates a laminate in which green sheets printed with internal electrodes are laminated with millimeter waves to bake the laminate, where 60% by mass or more of the components of the metal contained in the internal electrodes is Cu, and the frequency of the millimeter waves is 24 GHz or more and 28 GHz or less.

[0007] A multilayer electronic component according to an aspect of the present disclosure has a laminate in which ceramic layers and internal electrodes are alternately laminated, where 60% by mass or more of the components of the metal contained in the internal electrodes is Cu, and 60% by mass or more of the components of the ceramic layer are ceramics having a perovskite structure and represented by the composition formula ABO3, where the A site is Ca, Sr, or Ba, or a combination of two or more of these, the B site is Zr, or a combination of Zr and Ti, and the average value of the distance by which Cu diffuses into the ceramic layer from the boundary between the internal electrode and the ceramic layer is 300 nm or less at 20 at%.

Advantages of the Invention

[0008] According to the above configuration, for example, the diffusion of Cu into the ceramic layer is reduced. As a result, for example, the probability of dielectric breakdown occurring in the ceramic layer can be reduced.

Brief Description of the Drawings

[0009] [Figure 1] A cross-sectional view showing the configuration of a capacitor according to an embodiment. [Figure 2] A chart showing the manufacturing conditions and characteristics of comparative examples and examples. [Figure 3] A diagram showing the concentration distributions of comparative examples and examples.

Modes for Carrying Out the Invention

[0010] Generally, "microwaves" are often regarded as electromagnetic waves with frequencies ranging from 300 MHz to 300 GHz. Also, generally, "millimeter waves" are often regarded as electromagnetic waves with frequencies ranging from 30 GHz to 300 GHz. In the present disclosure, the term "millimeter wave" may also be used for electromagnetic waves with frequencies of 30 GHz or less. The "main component" of a material refers to, for example, a component that occupies 60 wt% or more, 80 wt% or more, or 100 wt% (excluding errors) of the material. In the description of embodiments, the term "main component" may be replaced with the term "component of 60 wt% or more", "component of 80 wt% or more", or "component of 100 wt%" as long as there is no contradiction.

[0011] (Overview of Embodiments) FIG. 1 is a cross-sectional view schematically showing the configuration of a capacitor 1 (an example of a multilayer electronic component) according to an embodiment. In FIG. 1, for convenience, a rectangular coordinate system xyz is attached. The capacitor 1 may have any direction defined as the vertical direction, but for convenience, the +z side is regarded as the upper side, and terms such as the upper surface may be used. As the manufacturing process progresses, the components of the capacitor 1 may change in terms of the composition and microstructure of the materials. For convenience, the same reference numerals may be used before and after the change, or the same terms may be used.

[0012] The capacitor 1 is a so-called multilayer ceramic capacitor and has a laminate 7 in which ceramic layers 11 and internal electrodes 13 are alternately laminated. The laminate 7 is produced, for example, by firing a laminate in which a ceramic green sheet that becomes the ceramic layer 11 and an electrode layer that becomes the internal electrode 13 are alternately laminated. In the firing process, the laminate (7) is heated by irradiating it with microwaves (including millimeter waves).

[0013] In the manufacturing method according to this embodiment, various effects can be obtained by appropriately setting the conditions when firing with microwaves. For example, when the metal of the conductive paste that becomes the internal electrode 13 contains copper (Cu) as the main component (not the main component of the conductive paste, but the main component of the metal), millimeter waves of 24 GHz to 28 GHz are irradiated onto the laminate. This can reduce, for example, the diffusion of Cu into the ceramic layer 11. For convenience, the term conductive paste may be used without distinguishing between the internal electrode 13 before and after drying when referring to the internal electrode 13 before firing with microwaves.

[0014] The above is an overview of the embodiment. Below, the embodiment will be described in general terms, in the following order. 1. Configuration of electronic components 1.1. Overall Capacitor Configuration 1.2. Capacitor Stack 1.3. Other examples of electronic components 2. Manufacturing methods for electronic components 2.1. Outline of the procedure 2.2. Firing using microwaves 3. Examples and Comparative Examples 3.1. Firing conditions and characteristics 3.2.Concentration distribution 4. Summary of Embodiments

[0015] (1. Configuration of electronic components) (1.1. Overall configuration of capacitors) The capacitor 1 illustrated in Figure 1 is a chip-type component that is surface-mounted on a circuit board or the like (not shown). The capacitor 1 may be a 2-terminal, 3-terminal, 4-terminal, or other type. Figure 1 shows a cross-section (for example, a planar cross-section) that crosses any two of the two or more terminals (external electrodes 5).

[0016] The shape of capacitor 1 is, for example, roughly rectangular. The specific dimensions (including dimensional ratios) of capacitor 1 are arbitrary. For example, the dimensions of a relatively small capacitor 1 may be between 0.01 mm and 1 mm in length, width, and thickness (maximum length in each of the three orthogonal directions).

[0017] The capacitor 1 has, for example, a main body 3 and external electrodes 5 that overlap the surface of the main body 3. The external electrodes 5 contribute to the electrical connection between the capacitor 1 and other electronic components (e.g., a circuit board not shown).

[0018] The main body 3 includes, for example, the laminated body 7 described above and a cover 9 that overlaps the laminated body 7 above and below. The laminated body 7 directly performs the function of a capacitor. The cover 9 contributes, for example, to insulating the laminated body 7 from the outside and to improving the strength of the main body 3.

[0019] A single layered (film-like) component (e.g., 9, 11, and 13) of the main body 3 may be composed entirely of one material. In this case, a single layered component may be composed of one layer during the manufacturing process, or it may be composed of two or more layers made of the same material. Furthermore, a single layered component may be composed of layers made of different materials stacked on top of each other. The same applies to the external electrode 5.

[0020] (1.2. Stacked capacitors) The ceramic layer 11 is basically a layered structure with a constant thickness (at least between the internal electrodes 13). The thickness of the ceramic layer 11 is arbitrary. For example, the thickness between adjacent internal electrodes 13 may be 0.1 μm or more, 0.5 μm or more, or 1.0 μm or more, and may also be 3.0 μm or less, 2.0 μm or less, or 1.0 μm or less. The above lower and upper limits may be combined in any way so as not to cause any contradiction. The number of layers of the ceramic layer 11 (internal electrodes 13) is arbitrary. For example, it may be 10 to 1000 layers.

[0021] The specific type of the material (ceramics) of the ceramic layer 11 is not particularly limited. For example, the main component of the ceramic layer 11 may be ceramics having a perovskite structure and represented by the composition formula ABO3. The A site may be, for example, Ca, Sr, or Ba, or a combination of two or more of these. The B site may be, for example, Zr or Ti, or a combination thereof.

[0022] Specifically, for example, the main component (the ceramic particles constituting the main component) may be CaZrO3, SrZrO3, Ca 1-x Sr x ZrO3, CaZr 1-y Ti y O3, SrZr 1-y Ti y O3, Ca 1-x Sr x Zr 1-y Ti y O3, BaTiO3, Ba 1-x Ca x TiO3, Ba 1-x Sr x TiO3, Ba 1-x-y Ca x Sr y TiO3, or Ba (1-x-y) Ca x Sr y Zr (1-z) Ti z O3, or a combination of two or more of these.

[0023] The internal electrode 13 is a layered one having a certain thickness. The internal electrodes 13 adjacent to each other in the stacking direction, for example, are connected to different (at least two) external electrodes 5. Thereby, a circuit having a plurality of parallel plate capacitors connected in parallel with each other is configured.

[0024] The thickness of the internal electrode 13 is arbitrary; for example, it may be thinner, the same thickness as, or thicker than the thickness of the region between the internal electrodes 13 in the ceramic layer 11. The specific example (μm) of the thickness of the ceramic layer 11 described above may be applied to the internal electrode 13. The material of the internal electrode 13 is, for example, a metal. The specific type of metal is arbitrary; for example, its main component is a base metal. Examples of base metals include Cu, Ni, or alloys containing at least one of these as the main component.

[0025] (1.3. Other examples of electronic components) Although not specifically illustrated, other examples of capacitor configurations and examples of electronic components other than capacitors are given.

[0026] The capacitor may have an outer resin covering the entire structure illustrated in Figure 1, and lead wires connected to the external electrodes 5 and extending from the outer resin. In another view, the capacitor may be a through-hole mounting type rather than a surface-mount type.

[0027] The two types of internal electrodes 13, each connected to a different external electrode 5, may be stacked alternately in pairs rather than one at a time. In this case, for example, the thickness of the ceramic layer 11 between two opposing internal electrodes 13 connected to the same external electrode 5 may be thinner than the thickness of the ceramic layer 11 between two opposing internal electrodes 13 connected to different external electrodes 5. As can be seen from this, the multiple ceramic layers 11 do not have to have the same shape and size.

[0028] Furthermore, the two types of internal electrodes 13 connected to different external electrodes 5 do not necessarily have to face each other. For example, a circuit in which two parallel plate capacitors are connected in series may be formed by providing two types of internal electrodes 13 connected to different external electrodes 5 on the same layer, and providing an internal electrode 13 facing the two types of internal electrodes 13. Alternatively, a circuit in which three or more parallel plate capacitors are connected in series may be formed.

[0029] The electronic component is not limited to a capacitor. For example, the electronic component may be a multilayer electronic component other than a capacitor. Examples of such electronic components include multilayer inductors, multilayer varistors, multilayer ferrite beads, multilayer thermistors, and multilayer filters. As can be seen from the examples of multilayer varistors and multilayer ferrite beads, the material of the ceramic layer 11 is not limited to a dielectric, but may be, for example, a semiconductor or a magnetic material.

[0030] A multilayer ceramic filter may, for example, have an LC circuit. As can be seen from this example, an electronic component may implement two or more functions (capacitor and inductor). The parts that implement different functions may be different parts in a planar view and / or different parts in a side view.

[0031] (2. Methods for manufacturing electronic components) (2.1. Outline of the procedure) Using capacitor 1 as an example of an electronic component, we will explain its manufacturing method. The manufacturing method of capacitor 1 can be various, except for the conditions of microwave irradiation during firing. For example, the general procedure may be the same as a known procedure. An example is shown below.

[0032] First, ceramic green sheets, which will form the ceramic layer 11 and the cover 9, are fabricated. Next, conductive paste, which will form the internal electrode 13, is printed onto the ceramic green sheets. The cover 9 may also be constructed by laminating dummy electrodes (not shown) and / or base electrodes (not shown) for the external electrode 5, which are placed on the ceramic green sheets. Next, the ceramic green sheets are laminated to create a laminate that will form the main body 3.

[0033] Up to the point of fabricating the laminate described above, the process is carried out using a base substrate that is large enough to produce multiple main body parts 3. After fabricating the laminate, the base substrate containing the laminate is pieced into pieces (for example, cut) that roughly correspond to the size of the main body parts 3. Next, the laminate having the size of the main body parts 3 is fired. After that, a metal film is formed on the main body parts 3 to form the external electrodes 5.

[0034] Furthermore, degreasing may be performed before firing. Polishing (e.g., barrel polishing) of the main body 3 may be performed before and / or after firing.

[0035] The ceramic green sheet includes, for example, ceramic powder, an organic binder, and a solvent. The average particle size of the ceramic powder may be, for example, 0.1 μm to 1.5 μm. The conductive paste includes, for example, metal powder, an organic binder, and a solvent. The conductive paste may also contain ceramic powder (common material) made of the same type of material as the ceramic powder contained in the ceramic green sheet. The average particle size of the metal powder may be, for example, 10 nm to 1000 nm.

[0036] (2.2. Firing using microwaves) Examples of conditions for microwave firing are shown below. • Frequency: 10GHz to 100GHz, or 24GHz to 28GHz • Firing temperature: 950℃ to 1080℃ • Holding time at firing temperature: 1 hour or more (no upper limit), or 3 hours or more but 5 hours or less. • Heating rate: 10°C / min or more, and 30°C / min or less • Cooling speed: No particular restrictions. • Atmosphere: Reduced atmosphere Oxygen partial pressure: 0.2 atm or less (no lower limit), 10 -10 atm over 10 -3 ATM or less, or 10 -10 atm over 10 -7 below atm

[0037] The temperatures related to the firing temperature, heating rate, and cooling rate may be, for example, the surface temperature of the laminate being fired (the laminate corresponding to the main body 3 in the illustrated example) (or the average temperature if there is temperature variation depending on the location).

[0038] (3. Examples and Comparative Examples) Various capacitors 1 were fabricated using different firing conditions, and their characteristics were investigated. An example is shown below.

[0039] (3.1. Firing conditions and characteristics) Figure 2 is a chart showing the firing conditions and characteristics of capacitor 1 for the comparative example and the example. As shown in the "Equipment" column, the comparative example was fired using a batch furnace (electric furnace), while the example was fired using millimeter-wave irradiation. As shown in the "Temperature" column, the firing temperature was 1030°C for both examples.

[0040] The other conditions were set as follows, as shown in each column of Figure 2. • Millimeter wave frequency (in the "Equipment" column): 24GHz or 28GHz • Hours (hrs): 1.0, 3.0, or 5.0 Oxygen partial pressure (atm): 10 -10 or 10 -7 Note that "time" refers to the time during which the firing temperature (1030°C) was maintained.

[0041] Eight different examples (Examples 1-4 and 6-9) were established by varying the frequency (2 types) x time (3.0 or 5.0) x oxygen partial pressure (2 types). Additionally, Example 5 was established by changing the firing temperature holding time to 1.0h in Example 3 or 4. Unless otherwise specified, the conditions are the same in the comparative examples and the examples.

[0042] In Figure 3, the columns for "Capacitance (pF)," "Q-value," and "Breakdown Voltage BDV (V)" show the measured characteristics. The Q-value is the value at 1.0 MHz. For each comparative example and each example, five samples were prepared and measured. The values ​​shown are the average values.

[0043] The conditions for Examples 2 and 7 were the same as those for the Comparative Example, except that the firing was performed using millimeter waves. While the comparative example had a BDV of 900V, the BDVs for Examples 2 and 7 were 998V and 1033V, respectively. In other words, the use of millimeter waves (more specifically, 24GHz or 28GHz) resulted in a higher BDV.

[0044] The reasons for the above effects include, for example, the following: 24 GHz to 28 GHz is a frequency that can efficiently heat the Cu contained in the internal electrode 13. Therefore, during firing, the temperature of the Cu rises, and as a result, the temperature of the ceramic green sheet also rises. Consequently, heating does not proceed from the surface of the laminate, but rather proceeds uniformly over the Cu distribution area (for example, roughly the entire laminate). Furthermore, because heating proceeds uniformly, the heating time can also be shortened. By equalizing the heating and shortening the heating time, the likelihood of increased diffusion in areas where the temperature is locally higher is reduced. Furthermore, generally speaking, the smaller the ionic charge, the less diffusion occurs in monovalent (non-ionic) materials than in divalent (non-ionic) materials, taking copper as an example. This can be explained by the Pondelomotive force.

[0045] Examples 1 to 9 all demonstrate the effects described above compared to heating by an electric furnace. Furthermore, Examples 1 to 4 and 6 to 9 exhibit capacity, Q value, and BDV values ​​that are sufficiently suitable for practical use, as can be seen from the comparison with the comparative examples.

[0046] For reference, the conditions other than the firing conditions for the comparative examples and examples are shown below. • Ceramic green sheet (which will become ceramic layer 11) Composition of ceramic particles: CaZrO3 (as the main component) Thickness: 4μm • Conductive paste (which will become the internal electrode 13) • Type of metal particle: Cu Thickness: 2μm

[0047] (3.2.Concentration distribution) Figure 3 shows the concentration distribution in the comparative example and Example 1. The horizontal axis represents distance (nm). "0" on the horizontal axis corresponds to the boundary BL between the internal electrode 13 and the ceramic layer 11. The negative side of the horizontal axis is the internal electrode 13 side. The positive side of the horizontal axis is the ceramic layer 11 side. The vertical axis represents the concentration, and more specifically, it shows the ratio of the number of Cu atoms to the total number of atoms at the position on the horizontal axis in the range of 0 to 1. Figure 3 was created as follows.

[0048] Magnified images of predetermined xz cross-sections (see Figure 1) of capacitor 1 according to the comparative example and Example 1 were obtained using a Scanning Electron Microscope (SEM). The magnified images were color-coded according to the at% of Cu using a function attached to the SEM. In the magnified images, multiple observation positions were set at equal intervals in the x-direction for each of the multiple internal electrodes 13. At each observation position, the z-direction position of the boundary of the color-coded area (i.e., the part with a specific density) was identified. The boundary BL between the internal electrode 13 and the ceramic layer 11 (the z-direction position differs slightly depending on the x-direction position) was also visually identified. The distance (z-direction length) from the boundary BL to the position with the specific density was then measured.

[0049] Points P0 and P1 show the relationship between concentration and distance measured as described above. Point P0 corresponds to the comparative example. Point P1 corresponds to the example. Lines L0 and L1 are approximation curves of points P1 and P0, obtained by the diffusion equation. Therefore, lines L0 and L1 can be considered to represent the average concentration distribution of the comparative example and the example, respectively.

[0050] As shown in Figure 3, line L1 is located closer to the internal electrode 13 than line L0. That is, the diffusion of Cu into the ceramic layer 11 is suppressed. More specifically, it is as follows: • Distance at which Cu diffuses from boundary BL to ceramic layer 11 at a rate of 40 at% L0: 100nm or higher L1: Below 100nm, and even below 50nm • Distance at which Cu diffuses from boundary BL to ceramic layer 11 at a rate of 20 at% L0: 400nm or higher L1: Below 300nm, and even below 200nm • Distance at which Cu diffuses from boundary BL to ceramic layer 11 at a rate of 10 at% L0: 600nm or higher L1: Below 500nm, and even below 400nm

[0051] The average value obtained by a method other than the method for finding the approximation curve described above may fall within the range shown for line L1. For example, when the distance (z direction) at which Cu is diffused from the boundary BL at a specific rate (40 at%, 20 at%, or 10 at%) is determined at multiple observation positions (x direction) as described above, the simple average value of these values ​​may fall within the range of line L0. In any case, similar results can be obtained by setting a sufficient number of observation positions evenly.

[0052] Furthermore, in determining the approximate curve and mean value, specific cross-sections (e.g., the xz cross-section located at the y-direction end of capacitor 1) may be avoided. Alternatively, the approximate curve or mean value may be determined based on multiple cross-sections (e.g., five or more) evenly spaced in the y-direction. If it is difficult to observe multiple cross-sections from a single sample, cross-sections from multiple samples intended to have the same configuration may be used. The number of observation positions may be, for example, 50 or more, or 100 or more.

[0053] The inventors used Boltzmann-Matano analysis based on approximation curves (lines L0 and L1) to determine the diffusion coefficient (nm). 2The value of / s) has also been identified. The value is shown below. Although not shown in Figure 3, the same identification was performed for Example 3. Comparison example: 0.13 Example 1: 0.03 Example 3: 0.06 By comparing the diffusion coefficients of the comparative example and the example, it is clear that under the same level of reducing atmosphere, calcination using millimeter waves results in less Cu diffusion than calcination using a batch furnace (sintering furnace).

[0054] (5. Summary of the Embodiments) Below, we will extract configurations and / or procedures according to the embodiment and describe their effects. Note that the extracted configurations and / or procedures do not necessarily have to produce the effects exemplified below.

[0055] The manufacturing method for the capacitor 1 (an example of a multilayer electronic component) according to this embodiment involves firing a laminate (7) formed by stacking ceramic green sheets (11) on which (unfired) internal electrodes 13 are printed, by irradiating the laminate (7) with millimeter waves. 60% or more of the metal component in the internal electrodes 13 is Cu. The frequency of the millimeter waves is between 24 GHz and 28 GHz.

[0056] Therefore, for example, the internal electrode 13 can be effectively heated by millimeter waves having a frequency corresponding to Cu. As a result, for example, the probability of Cu dispersing in the ceramic layer 11 can be reduced, and consequently, the BDV can be increased.

[0057] In the ceramic green sheet (11), 60% by mass or more of the ceramic components may have a perovskite structure and be represented by the compositional formula ABO3. The A site may be Ca, Ba, or Sr, or a combination of two or more of these. The B site may be Zr, or a combination of Zr and Ti.

[0058] In this case, for example, the ceramic material, as in the example, has an alkaline earth metal at site A and contains zirconium at site B. Therefore, the effect of increasing BDV is easily obtained.

[0059] The oxygen partial pressure when firing the laminate (7) is 10 -10 atm over 10 -7 It's also acceptable to have an ATM or lower.

[0060] In this case, for example, the oxygen partial pressure is within the range in which the effect of increasing BDV was confirmed in the examples. Therefore, the effect of increasing BDV is easily obtained. Also, if the oxygen partial pressure is 10 -7 The formation of copper oxide is reduced when the oxygen partial pressure is below atm. -10 A pH of 0.5 or higher reduces the likelihood of oxygen vacancies occurring in zirconate-based ceramics.

[0061] During the firing of the laminate (7), the temperature of the laminate (7) may be maintained at 950°C to 1080°C for a period of 3 hours to 5 hours.

[0062] In this case, for example, the firing temperature and holding time are within the range in which an effect of increasing BDV was confirmed in the examples. Therefore, the effect of increasing BDV is easily obtained. Example 5 shows that when the holding time is less than 3 hours, the effect of increasing BDV becomes difficult to obtain. On the other hand, when comparing examples where the conditions other than holding time are the same, the BDV does not necessarily increase when the holding time is increased from 3 hours to 5 hours. Therefore, by setting the BDV to between 3 hours and 5 hours, it is possible to obtain the effect of increasing BDV while reducing costs related to electricity, etc.

[0063] The capacitor 1 according to this embodiment has a laminate 7 in which ceramic layers 11 and internal electrodes 13 are alternately stacked. 60% by mass or more of the metal component in the internal electrodes 13 is Cu. 60% by mass or more of the ceramic layer 11 is a ceramic having a perovskite structure and represented by the compositional formula ABO3. The A site is Ca, Ba, or Sr, or a combination of two or more of these. The B site is Zr, or a combination of Zr and Ti. The average distance over which Cu diffuses from the boundary between the internal electrodes 13 and the ceramic layer 11 to the ceramic layer 11 at a rate of 20 at% is 300 nm or less.

[0064] Therefore, for example, the diffusion of Cu into the ceramic layer 11 is relatively small, and the BDV is relatively large. Such a capacitor 1 is realized for the first time by the manufacturing method according to this embodiment.

[0065] The following concepts can be extracted from this disclosure. (Concept 1) A laminate made of green sheets with printed internal electrodes is irradiated with millimeter waves to sinter the laminate, The metal contained in the internal electrode is composed of 60% by mass or more of Cu. The aforementioned millimeter wave frequency is between 24 GHz and 28 GHz. Manufacturing method for multilayer electronic components. (Concept 2) In the aforementioned green sheet, 60% or more of the ceramic components have a perovskite structure and are represented by the compositional formula ABO3. Site A is Ca, Ba, or Sr, or a combination of two or more of these. Site B is Zr, or a combination of Zt and Ti. A method for manufacturing a stacked electronic component as described in Concept 1. (Concept 3) When firing the laminate, the oxygen partial pressure is 10 -10 atm over 10 -7 It is less than or equal to atm Manufacturing method for multilayer electronic components according to Concept 1 or 2 (Concept 4) In firing the laminate, the temperature of the laminate is maintained at 950°C to 1080°C for a period of 3 hours to 5 hours. A method for manufacturing a stacked electronic component as described in any one of Concepts 1 to 3. (Concept 5) It has a laminate in which ceramic layers and internal electrodes are alternately stacked, The metal contained in the internal electrode is composed of 60% by mass or more of Cu. At least 60% by mass of the ceramic layer is a ceramic having a perovskite structure and represented by the compositional formula ABO3. Site A is Ca, Ba, or Sr, or a combination of two or more of these. Site B is Zr, or a combination of Zr and Ti. The average distance over which Cu diffuses from the boundary between the internal electrode and the ceramic layer into the ceramic layer at a rate of 20 at% is 300 nm or less. Stacked electronic components. [Explanation of Symbols]

[0066] 1...Capacitor (multilayer electronic component), 11...Ceramic layer, 13...Internal electrode.

Claims

1. A laminate made of green sheets with printed internal electrodes is irradiated with millimeter waves to sinter the laminate, The metal contained in the internal electrode is composed of 60% by mass or more of Cu. The frequency of the aforementioned millimeter wave is between 24 GHz and 28 GHz. Manufacturing method for multilayer electronic components.

2. 60% or more of the ceramic components in the aforementioned green sheet have a perovskite structure and compositional formula ABO ３ It is represented by, Site A is Ca, Ba, or Sr, or a combination of two or more of these. Site B is Zr, or a combination of Zt and Ti. A method for manufacturing a stacked electronic component according to claim 1.

3. When firing the laminate, the oxygen partial pressure is 10 －１０ atm over 10 －７ It is less than ATM. A method for manufacturing a stacked electronic component according to claim 2.

4. In firing the laminate, the temperature of the laminate is maintained at 950°C to 1080°C for a period of 3 hours to 5 hours. A method for manufacturing a stacked electronic component according to claim 3.

5. It has a laminate in which ceramic layers and internal electrodes are alternately stacked, The metal contained in the internal electrode is composed of 60% by mass or more of Cu. 60% by mass or more of the ceramic layer has a perovskite structure and composition formula ABO ３ These are ceramics represented by Site A is Ca, Ba, or Sr, or a combination of two or more of these. Site B is Zr, or a combination of Zr and Ti. The average distance over which Cu is diffused at a rate of 20 at% from the boundary between the internal electrode and the ceramic layer to the ceramic layer is 300 nm or less. Stacked electronic components.

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