Dielectric ceramic composition and ceramic capacitor using the same dielectric ceramic composition

Abstract

The present invention discloses a dielectric ceramic formulation in which ceramic dielectric layers and base metal internal electrodes are alternately laminated to obtain a multilayer ceramic capacitor. 1-x K x ) s A 1-s ] m [(Nb 1-y Ta y ) u B1 v B2 w )]O3, in which A is one element selected from the alkaline earth elements Mg, Ca, Sr, and Ba, B1 is one element selected from Ti, Zr, Hf, and Sn, B2 is one element selected from the group of transition metal elements, x, y, s, u, v, and w are the mole fractions of each element, and m is [(Na 1-x K x ) s A 1-s ] and [(Nb 1-y Ta y ) u B1 v B2 w ), within the following ranges: 0.93≦m≦1.07, 0.7≦s≦1.0, 0.00≦x≦0.05, 0.00≦y≦0.65, 0.7≦u≦1.0, 0≦v≦0.3, 0.001≦w≦0.100.

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the priority of U.S. Provisional Application No. 63 / 142,752, filed on January 28, 2021, the content of which is incorporated herein by reference.

[0002] This application relates to a dielectric ceramic composition and a multilayer ceramic capacitor using the dielectric ceramic composition. The dielectric ceramic composition enables co - firing with a base - metal - containing internal electrode at a low oxygen partial pressure, and the multilayer ceramic capacitor manufactured using this composition is used for high - temperature applications.

Background Art

[0003] With the rapid growth of the information and electronics industries over the past 20 years, the manufacturing of multilayer ceramic capacitors has thrived greatly due to the increasing demand for electrical energy storage components in many applications such as portable electronic devices, personal computers, mobile phones, televisions, etc. In these cases, BaTiO3 has been overwhelmingly adopted as an essential ceramic dielectric material because of its high dielectric constant, dielectric loss, and stable capacitance variation over the temperature range of -55°C to 125°C. However, BaTiO3 is well-known as a ferroelectric material that undergoes a ferroelectric - paraelectric phase transition at about 125°C, resulting in a significant decrease in the dielectric constant along with a sharp decrease in the capacitance temperature coefficient. These days, with the emergence of new electronic technology applications in extreme environments such as engine control units, downhole drilling exploration, pulse power electronics, etc., the maintenance of stable capacitance at the maximum operating temperature window of 175°C to 200°C or higher temperatures is required. Extensive research activities have been carried out to stabilize the temperature - capacitance characteristics of BaTiO3-based capacitors through a wide range of doping modification packages, but the extended operating temperature is still limited to 150°C. However, considerable attention has been focused on developing new dielectric materials that enable application in severe environments at 175°C to 200°C or higher temperatures. Recently, alkaline niobate-based ceramics such as NaNbO3 have been found as viable candidates for developing high-temperature capacitors with appropriate doping selection. Doping of alkaline earth zirconates such as CaZrO3 and SrZrO3 or alkaline earths such as CaHfO3 and SrHfO2 is also being considered.

[0004] In the detailed firing studies and defect chemistry investigations reported in the literature, it has been proposed that alkaline niobate ceramics can be co-fired with base metals such as Cu and Ni at low oxygen partial pressures by well-adjusted chemical thermodynamics that reduce the volatility of alkaline elements. In U.S. Patent No. 9,564,271 and WO2018 / 062084A1, which are incorporated by reference, it has been demonstrated that (K, Na)NbO3-based and NaNbO3-based ceramics are comparable to co-firing with Ni internal electrodes in a reducing atmosphere, respectively. However, the dielectric ceramic compositions disclosed in both contain Li. As a light element, Li is known to move easily in electroceramic materials and can introduce high leakage currents, especially in severe environments such as under high voltage and / or high temperature, or in a high humidity environment. Clearly, this leakage current is harmful to dielectric capacitors in terms of insulation stability and lifetime reliability.

[0005] Despite great efforts, new formulations that meet the demands of recent electronic devices are still required. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0006] The present invention relates to improved ceramics in which the ceramics exhibit better thermal stability. The present invention also relates to an improved capacitor including this improved ceramic. MEANS FOR SOLVING THE PROBLEMS

[0007] As will be appreciated, these and other embodiments are dielectric ceramic compositions comprising [(Na 1-x K x ) s A 1-s ) m [(Nb 1-y Ta y ) u B1 v B2 w )]O3 as the main component, wherein in the formula, A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba, B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn, B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn, x, y, s, u, v, and w are the molar fractions of each element, and m is [(Na 1-x K x ) s A 1-s and [(Nb 1-y Ta y ) u B1 v B2 w )]'s molar ratio, 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100 as the main component, and a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Yu, a second sub-component containing frit, are provided in the dielectric ceramic composition.

[0008] Another embodiment further provides a multilayer ceramic capacitor, which is a plurality of dielectric ceramic layers, and each layer of the layers is [(Na 1-x K x ) s A 1-s m [(Nb 1-y Ta y ) u B1 v B2 w )]O3 as the main component defined by the formula, where ​A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba, B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn, B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn, x, y, s, u, v, and w are the mole fractions of each element, and m is [(Na 1-x K x ) s A 1-s and [(Nb 1-y Ta y ) u B1 v B2 w )] is the molar ratio of, 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100 as the main component, and a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Yu, a second sub-component containing frit, and a dielectric ceramic layer containing a dielectric composition defined by, a plurality of internal electrodes containing base metals of Ni, Cu, or alloys thereof, a pair of external electrodes formed at each end of the capacitor element body, provided in a multilayer ceramic capacitor.

[0009] Still another embodiment is a method of forming a multilayer ceramic capacitor, forming a dielectric ceramic precursor, forming a stack by alternately arranging a metal layer and a layer of the dielectric ceramic precursor, compressing the stack and sintering the dielectric precursor, [(Na 1-x K x ) s A 1-s m [(Nb 1-y Ta y ) u B1 v B2 w )]O3 which is the main component defined by the formula, wherein A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; x, y, s, u, v, and w are the mole fractions of each element, and m is the molar ratio of [(Na 1-x K x ) s A 1-s and [(Nb 1-y Ta y ) u B1 v B2 w )]; 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100, and a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Yu; forming a dielectric ceramic layer having a dielectric composition defined by a second sub-component containing frit. A method for forming a multilayer ceramic capacitor is provided, including this step.

Brief Description of the Drawings

[0010] ​​

Figure 1

DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention provides a dielectric ceramic composition that enables good temperature-capacitance characteristics from low to high temperatures. Specifically, a capacitor made of the disclosed dielectric ceramic composition can have a capacitance temperature coefficient within ±25% over a temperature range of -55°C to 200°C with respect to the capacitance at 25°C. The advanced dielectric ceramic has a dielectric constant of at least 100, preferably at least 900 to 2000 or less at 25°C.

[0012] The present invention also provides a dielectric ceramic composition comparable to a co-fired internal electrode using inexpensive base metals such as Ni in a reducing atmosphere.

[0013] Therefore, the present invention provides a multilayer ceramic capacitor device formed by a plurality of stacked ceramic layers and a plurality of internal electrode layers in a pattern in which the ceramic layers and the internal electrode layers are alternately stacked. The ceramic layer is made of the present dielectric composition, and the internal electrode layer is made of a conductive paste mainly containing a non-metal such as Ni. The obtained multilayer ceramic capacitor can have a capacitance temperature coefficient within ±25% over a temperature range of -55°C to 200°C after co-firing in a low oxygen partial pressure.

[0014] The above object can be achieved in a multilayer ceramic capacitor using a dielectric ceramic composition, and the dielectric ceramic composition is [(Na 1-x K x ) s A 1-s ) m [(Nb 1-y Ta y ) u B1 v B2 w )]O3 wherein A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn; B2 is at least one element selected from transition metal elements; x, y, s, u, v, and w are mole fractions of each element, and m is the molar ratio of [(Na 1-x K x ) s A 1-s and [(Nb 1-y Ta y ) u B1 v B2 w . These are within the following respective ranges. 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100

[0015] Together with this main component, secondary components are also included.

[0016] The first secondary component consists of at least one element selected from rare earth compounds, which is 10 mol% or less relative to the main component. The second secondary component contains a compound with a low melting temperature that supports the ceramic sintering process, also known as frit, which is Li-free and is preferably at least one compound selected from fluorides, silicates, borides, and oxides. The content of the frit is within the range of 0.01 mol% to 15.00 mol% relative to the main component.

[0017] To obtain the disclosed dielectric ceramic composition, (1) the precursor is first prepared by calcination. Here, the precursor is defined as a group of intermediate compounds or compounds made from specific raw material ceramics powders. The precursor may contain all or part of the components of the final composition, but the final form of the material cannot be obtained until the precursor is further mixed with other reactants and processed under specific thermal conditions to achieve the desired chemical reaction. (2) Then, a mixture of the obtained precursor and other dopants such as transition metal compounds, rare earth compounds, and frit is further prepared in the form of a paste with the aid of various organic formulations prior to sintering. (3) Finally, the composition containing the obtained paste mixture forms the dielectric ceramic material disclosed in the present invention during the sintering process. An example is listed in Table 1. The precursor mainly contains NaNbO3-SrZrO3 ceramics, which are prepared by calcination with pre-reacted oxides and carbonates such as Na2CO3, SrCO3, Nb2O5, and ZrO2. The inorganic dopants used to form the paste prior to sintering are MnCO3, CeO2, and SiO2.

[0018]

Table 1

[0019] The dielectric ceramic material may also be obtained by other routes starting with more than one precursor as exemplified in Table 2 using the same starting raw materials as in Table 1. In this case, the two precursors are mainly made separately by calcination, with precursor 1 mainly containing NaNbO3 and precursor 2 mainly containing SrZrO3. Then, the paste is formed by a formulation of NaNbO3, SrZrO3, MnCO3, CeO2, and SiO2 together with an organic mixture. After sintering, the formulation in Table 2 results in a dielectric material composition that is substantially the same as that made by the formulation in Table 1.

[0020]

Table 2

[0021] The following description will be given in more complete embodiments that illustratively show the foregoing and other features of the present invention without limitation. However, these examples show only some of the various ways in which the principles of the present invention may be applied and are not intended to limit the scope of the present invention.

[0022] The dielectric ceramic composition of the present invention includes a main component together with sub-components, and the above main component is [(Na 1-x K x ) s A 1-s m [(Nb 1-y Ta y ) u B1 v B2 w )]O3…(1) represented by the formula, wherein A is at least one selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba, and A is preferably Ba, Sr, and / or Ca. B1 is at least one selected from Ti, Zr, Hf, and Sn, and B1 is preferably Zr and / or Hf. B2 is a transition metal element, and is preferably one selected from V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, Zn, and mixtures thereof, and B2 is at least one of V, W, Mo, Cr, and Mn.

[0023] In formula 1, x, y, s, u, v, and w are the molar fractions of each element, and m is the molar ratio of [(Na 1-x K x ) s A 1-s and [(Nb 1-y Ta y ) u B1 v B2 w )]. These are within the following respective ranges. 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65,​ 0.7 ≤ u ≤ 1.0, 0 ≤ v ≤ 0.3, 0.001 ≤ w ≤ 0.100

[0024] The first sub-component preferably contains at least one rare earth element selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu. The amount of the rare earth element added is 10 mol% or less based on the main component. The value of the molar fraction is calculated based on YO 3 / 2 , ScO 3 / 2 , LaO 3 / 2 , CeO2, PrO 11 / 6 , NdO 3 / 2 , SmO 3 / 2 , EuO 3 / 2 , GdO 3 / 2 , TbO 7 / 4 , DyO 3 / 2 , HoO 3 / 2 , ErO 3 / 2 , TmO 3 / 2 , YbO 3 / 2 and LuO 3 / 2 .

[0025] The second sub-component contains a compound having a low melting temperature called frit to assist the ceramic sintering process. The composition of the frit is not limited to any form and may preferably be at least one selected from fluorides such as NaF, KF, MgF2, silicates such as Si, SiO2, (Ba x Sr y Ca 1-x-y )SiO3 (0 ≤ x, y ≤ 1), borides such as B2O3, and oxides such as Na2O, MoO3, V2O5. The content of the frit is in the range of 0.01 mol% to 15.00 mol% based on the main component. The frit is defined as not containing Li as a main component, taking into account Li impurities that cannot actually be removed, with less than 0.10 mol% of lithium, preferably less than 0.05 mol% of lithium, more preferably less than 0.01 mol% of lithium, and even more preferably an amount of lithium below the detection limit.

[0026] In the ceramic layer 2 of the multilayer ceramic capacitor 1 shown in FIG. 1, to obtain the dielectric ceramic composition of the present disclosure, K2CO3, Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, TiO2, ZrO2, HfO2, transition metal compounds, rare earth compounds, and frit are prepared as starting ceramic raw materials. The proportions of these compounds in the raw materials are predetermined so that the dielectric ceramic composition disclosed in the present invention can be obtained after sintering. Further, in the dielectric formulation of the present disclosure, the raw material compounds containing each component may use not only oxides and carbonates but also hydroxides. Specifically, the raw materials are not limited to any form. For example, Mn can be added in the form of MnO, MnO2, MnCO3, etc., and this applies to all other raw materials as well. After the raw materials as the main components are weighed to satisfy the composition preparation of the present disclosure, they are wet-mixed together with a suitable solvent such as water, ethanol, isopropanol, toluene, ethyl acetate, propyl acetate, butyl acetate, mineral spirit, or other suitable hydrocarbon liquids, or blends thereof through ball milling with yttrium-stabilized zirconium media. In this way, a ceramic material before sintering is obtained after drying and calcination.

[0027] The calcined powder disclosed herein is further wet-milled by adding water and / or other suitable organic additives such as binders, dispersants, solvents, plasticizers, etc. to form a ceramic slip. The selection of the organic additives or organic contents used here is not particularly limited.

[0028] Thereafter, to obtain the ceramic slip and the ceramic composition of the present disclosure, the preparation steps are not limited to the above-described steps. After the precursor material is first calcined, it can be mixed with the precursor or the dopant contains other components of the desired composition, and in such a way that a ceramic slip is formed with suitable organic additives prior to sintering.

[0029] Examples 1 to 4 illustrate the present invention but do not limit the scope of the present invention. Within the scope of the present invention, modifications obvious to those skilled in the art are included.

[0030] Example 1 K2CO3, Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, TiO2, and ZrO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750°C to 1300°C. The starting ceramic materials are 0.1 mol% to 2.0 mol% of K from K2CO3, 90.0 mol% to 95.5 mol% of Na from Na2CO3, 0.1 mol% to 2.7 mol% of Ba from BaCO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.05 mol% to 1.20 mol% of Ti from TiO2, 0.1 mol% to 6.6 mol% of Zr from ZrO2, including, a mixture of transition metal oxides, rare earth oxides, and frit is 0.1 mol% to 2.4 mol% of Mn from MnO2, Pr6O 11 0.2 mol% to 4.8 mol% of Pr from 0.01 mol% to 3.30 mol% of frit from SiO2 including, is added as a dopant together with a suitable organic additive to form a ceramic slip.

[0031] Example 2 K2CO3, Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO2, HfO2 and transition metal oxides such as MnO2 and MoO3 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material is 0.1 mol% to 2.0 mol% of K from K2CO3, 90.0 mol% to 95.5 mol% of Na from Na2CO3, 0.1 mol% to 1.7 mol% of Ba from BaCO3, 0.1 mol% to 3.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.01 mol% to 0.80 mol% of Mo from MoO3 and a mixture of rare earth oxides and frit contains 0.6 mol% to 5 mol% of Y from Y2O3, 0.01 mol% to 3.30 mol% of frit from CaSiO3 is added as a dopant together with a suitable organic additive to form a ceramic slip.

[0032] Example 3 Rare earth oxides such as Na2CO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO2, HfO2 and Y2O3 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material is 87.0 mol% to 92.5 mol% of Na from Na2CO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, Pr6O 11 containing 0.2 mol% to 3.7 mol% of Pr from Pr6O including, the mixture of rare earth oxides and frit 0.1 mol% to 2.7 mol% of Mn from MnO2, 0.01 mol% to 3.30 mol% of frit from NaF is added as a dopant together with a suitable organic additive to form a ceramic slip.

[0033] Example 4 Na2CO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO 2、 and rare earth oxides such as La2O3, transition metal oxides such as MnO2, and rare earth oxides such as La2O3 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic materials are 87.0 mol% to 92.5 mol% of Na from Na2CO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 87.0 mol% to 92.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.2 mol% to 4.8 mol% of La from La2O3, including, the frit is 0.01 mol% to 5.90 mol% of NaF is included and added as a dopant together with a suitable organic additive to form a ceramic slip.

[0034] Furthermore, in order to obtain the desired dielectric composition disclosed in the present invention, dopants such as transition metal compounds, rare earth compounds, and frit can also be added in two separate steps. This means that a partial amount of the transition metal compound, rare earth compound, and / or frit is first added into the raw materials, and a precursor is prepared after firing at 750 °C to 1300 °C, which is defined as step 1. Then, the remaining amount of the transition metal compound, rare earth compound, and / or frit is further added to the precursor together with a suitable organic additive to form a ceramic slip, which is defined as step 2. The transition metal compounds added in step 1 and step 2 can be the same compound containing the same target transition metal element, or different compounds containing different target transition metal elements. This also applies to the rare earth compounds and frit when they are added separately in step 1 and step 2. The total amounts of the transition metal elements, rare earth elements, and frit added in step 1 and step 2 satisfy the value ranges specified in the present invention.

[0035] Examples 5 to 9 illustrate the present invention but do not limit the scope of the present invention. Modifications obvious to those skilled in the art are included within the scope of the present invention.

[0036] Example 5 Transition metal oxides such as Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO2, HfO2, and MoO3 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material is 87.0 mol% to 92.5 mol% of Na from Na2CO3, 0.1 mol% to 2.7 mol% of Ba from BaCO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 87.0 mol% to 92.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, 0.01 mol% to 0.80 mol% of Mo from MoO3, including, the mixture of transition metal oxides, rare earth oxides, and frit, 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.6 mol% to 5.0 mol% of Y from Y2O3, 0.01 mol% to 5.90 mol% of frit from NaF is further added as a dopant together with a suitable organic additive to form a ceramic slip.

[0037] Example 6 Transition metal oxides such as Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, TiO2, ZrO2, HfO 2、 and Y2O3 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material is 90.0 mol% to 95.5 mol% of Na from Na2CO3, 0.1 mol% to 1.7 mol% of Ba from BaCO3, 0.1 mol% to 3.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.05 mol% to 1.20 mol% of Ti from TiO2, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, 0.1 mol% to 2.2 mol% of Y from Y2O3 and the mixture of transition metal oxides, rare earth oxides, and frit contains, 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.1 mol% to 3.8 mol% of Dy from Dy2O3 0.01 mol% to 3.3 mol% of frit from CaSiO3 is further added as a dopant together with a suitable organic additive to form a ceramic slip.

[0038] Example 7 Transition metal oxides such as Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO2, and MnO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material contains, 90.0 mol% to 95.5 mol% of Na from Na2CO3, 0.1 mol% to 2.7 mol% of Ba from BaCO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.1 mol% to 2.2 mol% of Mn from MnO2~ and the mixture of rare earth oxides, transition metal oxides, and frit contains, 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.6 mol% to 5.0 mol% of Y from Y2O3, 0.01 mol% to 3.30 mol% of frit from KF Those containing are further added as dopants together with suitable organic additives to form ceramic slips.

[0039] Example 8 Transition metal oxides such as K2CO3, Na2CO3, SrCO3, CaCO3, Ta2O5, Nb2O5, ZrO2, HfO2, and WO3, and frit such as SiO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic material is 0.1 mol% to 2.0 mol% of K from K2CO3, 87.0 mol% to 92.5 mol% of Na from Na2CO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 87.0 mol% to 92.5 mol% of Nb from Nb2O5, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, 0.01 mol% to 0.80 mol% of W from WO3, 0.01 mol% to 0.85 mol% of frit from SiO2 including, and the mixture of rare earth oxides, transition metal oxides, and frit is 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.6 mol% to 4.0 mol% of Y from Y2O3, 0.01 mol% to 3.30 mol% of frit from BaSiO3 Those containing are further added as dopants together with suitable organic additives to form ceramic slips.

[0040] Example 9 Transition metal oxides such as Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, Nb2O5, TiO2, ZrO2, and MoO3, rare earth oxides such as Y2O3, and frit such as SiO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750°C to 1300°C. The starting ceramic material is 87.0 mol% to 92.5 mol% of Na from Na2CO3, 0.1 mol% to 2.7 mol% of Ba from BaCO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 87.0 mol% to 92.5 mol% of Nb from Nb2O5, 0.05 mol% to 1.20 mol% of Ti from TiO2, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.01 mol% to 1.80 mol% of Mo from MoO3, 0.1 mol% to 2.0 mol% of Y from Y2O3, 0.01 mol% to 1.40 mol% of frit from SiO2 and the mixture of rare earth oxide, transition metal oxide, and frit contains 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.6 mol% to 4.0 mol% of Y from Y2O3, 0.01 mol% to 3.30 mol% of frit from CaSiO3 and is further added as a dopant together with a suitable organic additive to form a ceramic slip.

[0041] Example 10 Frits such as Na2CO3, BaCO3, SrCO3, CaCO3, Ta2O5, Nb2O5, Nb2O5, TiO2, ZrO2, HfO2, and SiO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750°C to 1300°C. The starting ceramic material is 90.0 mol% to 95.5 mol% of Na from Na2CO3, 0.1 mol% to 2.7 mol% of Ba from BaCO3, 0.1 mol% to 5.3 mol% of Sr from SrCO3, 0.1 mol% to 6.6 mol% of Ca from CaCO3, 0.1 mol% to 5.5 mol% of Ta from Ta2O5, 90.0 mol% to 95.5 mol% of Nb from Nb2O5, 0.05 mol% to 1.20 mol% of Ti from TiO2, 0.1 mol% to 6.6 mol% of Zr from ZrO2, 0.05 mol% to 1.20 mol% of Hf from HfO2, 0.01 mol% to 1.40 mol% of frit from SiO2 and the mixture of rare earth oxides, transition metal oxides, and frit contains 0.1 mol% to 2.4 mol% of Mn from MnO2, 0.01 mol% to 2.60 mol% of W from WO3, 0.6 mol% to 5.0 mol% of Yb from Yb2O3, 0.01 mol% to 3.30 mol% of frit from B2O3 and is further added as a dopant together with a suitable organic additive to form a ceramic slip.

[0042] Example 11 Na2CO3, CaCO3, Nb2O5, Gd2O3, ZrO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750°C to 1300°C. The starting ceramic material is 84.0 mol% to 95.2 mol% of Na from Na2CO3, 0.1 mol% to 15.3 mol% of Ca from CaCO3, 84.0 mol% to 95.2 mol% of Nb from Nb2O5, 0.1 mol% to 15.3 mol% of Zr from ZrO2, 0.1 mol% to 7.2 mol% of Gd from Gd2O3, and the mixture of transition metal oxides and frit contains 0.1 mol% to 3.8 mol% of Mn from MnO2, 0.1 mol% to 4.2 mol% of frit from SiO2 is added as a dopant to the main component.

[0043] Example 12 Na2CO3, CaCO3, Nb2O5, Gd2O3, Ta2O5, ZrO2 are mixed as starting ceramic raw materials to prepare a precursor after calcination at 750 °C to 1300 °C. The starting ceramic materials contain 84.0 mol% to 95.2 mol% of Na from Na2CO3, 0.1 mol% to 15.3 mol% of Ca from CaCO3, 61.0 mol% to 75.6 mol% of Nb from Nb2O5, 0.5 mol% to 23.4 mol% of Ta from Ta2O5, 0.1 mol% to 15.1 mol% of Zr from ZrO2, 0.1 mol% to 6.6 mol% of Gd from Gd2O3, and the mixture of transition metal oxides and frit contains 0.1 mol% to 2.9 mol% of Mn from MnCO3, 0.1 mol% to 3.3 mol% of frit from SiO2 is added as a dopant to the main component.

[0044] Preparation of Ceramic Disk Samples The main component ceramic powder and the sub-components were weighed at the ratios described in the examples, and wet mixing was carried out in a ball mill for 12 to 30 hours. Thereafter, this mixture was dried at 150 °C for 1 to 8 hours. After adding the binder solution to the mixture in a mortar, it was formed into granules. Then, the obtained granules were put into a steel mold with a diameter of 13 mm and press-molded under a pressure of 200 MPa to produce a disk-shaped compact. The obtained compact was baked in air at 375 °C for 10 to 100 hours to burn out the organic binder. Next, combustion was carried out in a reducing atmosphere to obtain a sintered disk. This combustion was carried out at a peak temperature of 750 to 1300 °C for a holding time of 1 to 6 hours. Thereafter, silver electrodes were applied to two surfaces of the sintered body to obtain disk ceramic capacitors corresponding to Example 11 and Example 12.

[0045] Preparation of MLCC Samples By sintering in the temperature range of 750 to 1300 °C, a sintered MLCC chip having a standard size of 3.2 mm × 1.6 mm and nickel internal electrodes was obtained. The sintered MLCC chip included 19 active dielectric ceramic layers and 20 nickel electrodes. The average thickness of the dielectric ceramic layer was determined to be about 12 μm.

[0046] Electrical Measurement Values The capacitance and dielectric loss were measured for each composition under the conditions of 1 kHz and AC 1 V in the temperature range of -55 °C to 200 °C. The capacitance temperature coefficient (TCC) was calculated based on the following formula: TCC (%) = [(C T - C 25 ) / C 25 × 100 where T is the temperature at which the measurement was carried out, and C T and C 25 are the capacitances at temperature T and 25 °C, respectively.

[0047] The breakdown voltage (BDV) was measured at 25 °C with a voltage increase rate of 5 V per second.

[0048] The insulation resistance (IR) was measured after charging for 60 seconds under a DC voltage of 50 V at 25 °C.

[0049] Table 3 shows the dielectric properties of the disks prepared in Example 11 and Example 12 burned at 1250°C.

[0050]

Table 3

[0051] The results shown in Table 3 demonstrate that a capacitance temperature coefficient (TCC) within ±20% of the capacitance at 25°C, more preferably within ±5% of the capacitance at 25°C, and a wide range of dielectric constants can be obtained.

[0052] Table 4 shows the dielectric properties of the MLCCs prepared in Example 11 and Example 12 burned at 1250°C.

[0053]

Table 4

[0054] The results in Table 4 demonstrate the effect when the ceramic of the present invention is used in a multilayer ceramic capacitor.

[0055] The tape casting process is used to further form a ceramic green sheet by spreading a slip on a carrier film using the doctor blade method. After a suitable drying process, the internal electrodes 3a and 3b in FIG. 1 are screen printed on the ceramic green sheet using a conductive ink mainly containing a base metal such as Ni, Cu, or an alloy thereof. It is preferable to use Ni or an alloy mainly composed of Ni.

[0056] The obtained product is further processed into a green chip through a lamination process. After laminating a plurality of ceramic green sheets without printed electrodes as a bottom cover layer 4b, a plurality of ceramic green sheets with printed electrodes are laminated in alternating directions to form alternating current electrodes 3a and 3b that terminate at both ends, and finally, a specific number of ceramic green sheets without printed electrodes are laminated as an upper covering layer 4a. Then, this laminate is pressed between 20°C and 120°C to improve the adhesion of all laminations, and further cut into individual green chips. In this specification, the number of layers is not particularly limited, and 10 to several hundred layers are suitable for demonstrating the present invention.

[0057] The green chip is heated to 200°C to 700°C in ambient air or a slightly reduced atmosphere for 0.1 to 100 hours to burn out the binder, and then -16 atm to 10 -4 atm in a reducing atmosphere with an oxygen partial pressure between 750°C and 1300°C. After sintering, 10 -14 atm to 10 -3 atm in an oxygen partial pressure between 1100°C or lower by heating, a reoxidation step may be further applied to the chip. In this way, a sintered chip is achieved.

[0058] The sintered chip is subjected to a chamfering process by barrel or sandblasting to expose the internal electrodes formed at both ends of the ceramic sintered body. Then, external electrodes 5a and 5b are formed at both ends as follows. (1) A suitable copper paste is applied to both ends of the sintered chip, and baking is performed at a temperature of 600°C to 1000°C for 1 to 60 minutes in nitrogen or a slightly reduced atmosphere to form copper terminals. (2) By the barrel plating method, a nickel plating layer and a tin plating layer or other suitable solder composition are further placed on the copper terminals to improve solderability and prevent oxidation of the copper external electrodes. In this way, a multilayer ceramic capacitor 1 formed of the base metal electrodes 3a and 3b and the dielectric ceramic layer 2 containing the dielectric composition disclosed in the present invention is obtained.

[0059] The present invention discloses a dielectric ceramic composition applicable at high temperatures. Such a ceramic formulation can achieve co-firing with a base metal electrode in a reducing atmosphere. Therefore, by using the dielectric ceramic composition of the present disclosure together with a non-metal internal electrode such as Ni, a multilayer ceramic capacitor can be fabricated.

[0060] Throughout this description, all intermediate values having the same number of significant figures are included within the stated range. By way of non-limiting example, in the stated range of 0.01 to 0.05, 0.01, 0.02, 0.03, 0.04, and 0.05 are included. For a display having two numbers with different significant figures, when a range is displayed, the one having the smallest increment significant figure determines the significant figures for both. By way of non-limiting example, if a certain range is displayed as 1.0 to 5, it is intended to refer to all numbers from 1.0 to 5.0.

[0061] The following are incorporated herein by reference. U.S. Patent No. 9,564,271 to Banno et al. WO2018-062084A1 to Banno U.S. Patent No. 10,710,934 to Banno et al. Lead-free anti-ferroelectric: xCaZrO3-(1-x)NaNbO3 system (0≤x≤0.10), Shimizu et al., Dalton Transactions, Vol. 44, pp. 10763-10772, 2015 Strategy for stabilizing an anti-ferroelectric phase (Pbma) beyond a metastable ferroelectric phase (P21ma) for constructing double-loop hysteresis in a lead-free (1-x)NaNbO3-xSrZrO3 solid solution, Guo et al., Journal of Applied Physics, Vol. 117, p. 14103, 2015 Perovskite lead-free anti-ferroelectric xCaHfO3-(1-x)NaNbO3 with double hysteresis loops introduced at room temperature, Gao et al., Journal of Applied Physics, Vol. 120, p. 204102, 2016 Effect of Low Partial Pressure of Oxygen Treatment on Alkali Niobate NaNbO3, Shimizu et al., Journal of the American Ceramic Society, Vol. 97, No. 6, pp. 1791-1796, 2014 Base Metal Co-Fired Multilayer Piezoelectric Materials, Gao et al., Actuators, Vol. 5, No. 1, p. 8, 2016

[0062] The present invention will be described with reference to the drawings, which are an integral and non-limiting part of the specification provided for the accuracy of the present invention. Throughout the various drawings, like elements are designated by corresponding numbers. The present invention has been described with reference to preferred embodiments and is not limited thereto. Those skilled in the art will recognize additional embodiments in the accompanying drawings and the description thereof.

Claims

1. A dielectric ceramic composition comprising: [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ a main component defined by the formula: wherein A is at least one element selected from the group of alkaline earth elements Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of elements Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ ), and is 0.93 ≦ m ≦ 1.07, 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100; a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and a second sub-component containing frit, wherein the dielectric ceramic composition has a capacitance temperature coefficient of ±25% at a temperature of -55°C to 200°C; wherein the first sub-component is 10 mol% or less based on the main component; wherein the second sub-component is selected from the group consisting of fluoride, silicate, boride, and oxide; and wherein the second component is in the range of 0.01 mol% to 15.00 mol% based on the main component.

2. The dielectric ceramic composition according to claim 1, wherein the second component is Li-free.

3. A dielectric ceramic composition comprising: a main component defined by the formula: wherein [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ A is at least one element selected from the group of alkaline earth elements Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of elements Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; 0.93 ≦ m ≦ 1.07, x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ ), and is 0.7 ≦ s ≦ 1.0, 0 ≦ x ≦ 0.05, 0 ≦ y ≦ 0.65, 0.7 ≦ u ≦ 1.0, 0 ≦ v ≦ 0.3, 0.001 ≦ w ≦ 0.100; a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and a second sub-component containing frit, wherein the dielectric ceramic composition has a dielectric constant of at least 100 at 25°C. ​ The first sub-component is 10 mol% or less relative to the main component. The second sub-component is selected from the group consisting of fluorides, silicates, borides, and oxides. The second component is a dielectric ceramic composition within the range of 0.01 mol% to 15.00 mol% relative to the main component. **Claim 4** The dielectric ceramic composition according to claim 3, having a dielectric constant of at least 900 at 25°C. **Claim 5** A multilayer ceramic capacitor, comprising a plurality of dielectric ceramic layers, each layer of which [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ is a main component defined by, where in the formula, A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ ), and is 0.93 ≤ m ≤ 1.07, 0.7 ≤ s ≤ 1.0, 0 ≤ x ≤ 0.05, 0 ≤ y ≤ 0.65, 0.7 ≤ u ≤ 1.0, 0 ≤ v ≤ 0.3, 0.001 ≤ w ≤ 0.100, a main component, and a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and a second sub-component containing frit, defined by, where the first sub-component is 10 mol% or less relative to the main component, the second sub-component is selected from the group consisting of fluorides, silicates, borides, and oxides, the second component is a dielectric ceramic layer containing a dielectric composition within the range of 0.01 mol% to 15.00 mol% relative to the main component, the dielectric composition has a dielectric ceramic layer having a capacitance temperature coefficient of ±25% at a temperature of -55°C to 200°C, a plurality of internal electrodes containing a base metal of Ni, Cu, or an alloy thereof, and a pair of external electrodes formed at each end of the capacitor element body. **Claim 6** The multilayer ceramic capacitor according to claim 5, wherein the first sub-component is 10 mol% or less relative to the main component. **Claim 7** The multilayer ceramic capacitor according to claim 5, wherein the second sub-component is selected from the group consisting of fluorides, silicates, borides, and oxides. **Claim 8** The multilayer ceramic capacitor according to claim 5, wherein the second component is in the range of 0.01 mol% part to 15.00 mol% part with respect to the main component.

9. The multilayer ceramic capacitor according to claim 5, wherein the second component is Li-free.

10. A multilayer ceramic capacitor, comprising: A plurality of dielectric ceramic layers, each layer of which: [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ Is a main component defined by, wherein in the formula: A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and [[(Nb １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ )], and 0.93 ≤ m ≤ 1.07; 0.7 ≤ s ≤ 1.0; 0 ≤ x ≤ 0.05; 0 ≤ y ≤ 0.65; 0.7 ≤ u ≤ 1.0; 0 ≤ v ≤ 0.3; A main component with 0.001 ≤ w ≤ 0.100, A first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, And a second sub-component containing frit, The first sub-component is 10 mol% part or less with respect to the main component; The second sub-component is selected from the group consisting of fluoride, silicate, boride, and oxide; The second component is a dielectric ceramic layer containing a dielectric composition that is in the range of 0.01 mol% part to 15.00 mol% part with respect to the main component; The dielectric composition has a dielectric ceramic layer having a dielectric constant of at least 100 at 25°C; A plurality of internal electrodes containing a base metal of Ni, Cu, or an alloy thereof; And a pair of external electrodes formed at each end of the capacitor element body.

11. The multilayer ceramic capacitor according to claim 10, wherein the dielectric composition has a dielectric constant of at least 900 at 25°C.

12. A method for forming a multilayer ceramic capacitor, comprising: Forming a dielectric ceramic precursor; Forming a laminate by alternately arranging a metal layer and a layer of the dielectric ceramic precursor; Compressing the laminate and sintering the dielectric precursor to obtain a main component defined by, wherein in the formula: [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ ​ A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba, B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn, B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn, x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and [[(Nb １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ ), and 0.93 ≤ m ≤ 1.07, 0.7 ≤ s ≤ 1.0, 0 ≤ x ≤ 0.05, 0 ≤ y ≤ 0.65, 0.7 ≤ u ≤ 1.0, 0 ≤ v ≤ 0.3, 0.001 ≤ w ≤ 0.100, and a main component, a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, a second sub-component containing frit, and is defined by the first sub-component is 10 mol% or less with respect to the main component, the second sub-component is selected from the group consisting of fluoride, silicate, boride, and oxide, the second component is within the range of 0.01 mol% to 15.00 mol% with respect to the main component, and forming a dielectric ceramic layer having a dielectric composition, the dielectric composition is a method for forming a multilayer ceramic capacitor having a capacitance temperature coefficient of ±25% at a temperature of -55°C to 200°C.

13. The layer of the dielectric ceramic precursor is prepared as a ceramic green paste containing a mixture of an inorganic material and an organic additive, and the inorganic material includes at least one combination of a precursor and a dopant. The method for forming a multilayer ceramic capacitor according to claim 12.

14. The dopant is a transition metal element selected from the group consisting of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn, a rare earth element selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, and a frit group selected from the group consisting of fluoride, silicate, boride, and oxide, The method for forming a multilayer ceramic capacitor according to claim 13, which is selected from at least one of the groups consisting of

15. The method for forming a multilayer ceramic capacitor according to claim 13, comprising sintering the ceramic green paste.

16. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the sintering is performed at a temperature of 750°C to 1300°C.

17. The sintering is carried out at 10 －１６ atm to 10 －４ The method for forming a multilayer ceramic capacitor according to claim 12, which is carried out in an atmosphere with an oxygen partial pressure of atm.

18. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the first sub-component is 10 mol% or less based on the main component.

19. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the second sub-component is selected from the group consisting of fluorides, silicates, borides, and oxides.

20. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the second component is in the range of 0.01 mol% to 15.00 mol% based on the main component.

21. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the second component is Li-free.

22. The method for forming a multilayer ceramic capacitor according to claim 12, wherein the metal layer contains a base metal of Ni, Cu, or an alloy thereof.

23. The method for forming a multilayer ceramic capacitor according to claim 12, further comprising forming a pair of external electrodes at each end of the multilayer ceramic capacitor element.

24. A method for forming a multilayer ceramic capacitor, comprising: forming a dielectric ceramic precursor; forming a laminate by alternately arranging a metal layer and a layer of the dielectric ceramic precursor; compressing the laminate and sintering the dielectric precursor to obtain a main component defined by the following formula, wherein: [(Na １－ｘ K ｘ )( ｓ A １－ｓ ) ｍ [(Nb １－ｙ Ta ｙ )( ｕ B1 ｖ B2 ｗ )]O ３ A is at least one element selected from the group of alkaline earth elements of Mg, Ca, Sr, and Ba; B1 is at least one element selected from the group of Ti, Zr, Hf, and Sn; B2 is at least one element selected from the group of transition metal elements of V, Cr, Mo, W, Mn, Fe, Co, Ni, Cu, and Zn; 0.93 ≤ m ≤ 1.07; x, y, s, u, v, and w are the mole fractions of the respective elements, and m is the molar ratio of １－ｘ K ｘ ), ｓ A １－ｓ and [[(Nb １－ｙ Ta ｙ ), ｕ B1 ｖ B2 ｗ ), and 0.7 ≤ s ≤ 1.0; 0 ≤ x ≤ 0.05; 0 ≤ y ≤ 0.65; 0.7 ≤ u ≤ 1.0; 0 ≤ v ≤ 0.3; 0.001 ≤ w ≤ 0.100; a first sub-component containing at least one rare earth selected from the group consisting of Y, Sc, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu; and a second sub-component containing frit, wherein the first sub-component is 10 mol% or less based on the main component. ​ The second sub-component is selected from the group consisting of fluorides, silicates, borides, and oxides, The second component includes forming a dielectric ceramic layer having a dielectric composition within a range of 0.01 mol% part to 15.00 mol% part with respect to the main component, and the dielectric composition is a method for forming a multilayer ceramic capacitor having a dielectric constant of at least 100 at 25°C.

25. The method for forming a multilayer ceramic capacitor according to claim 24, wherein the dielectric composition has a dielectric constant of at least 900 at 25°C.

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