Dielectric ceramic composition and ceramic electronic component

Patent metadata

Field	Value
Publication number	US-11066332-B2
Application number	US-201716342515-A
Country	US
Kind code	B2
Filing date	Oct 11, 2017
Priority date	Oct 17, 2016
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

According to the present invention, a dielectric ceramic composition, which can be fired in a reducing atmosphere, has a high dielectric constant, has an electrostatic capacity exhibiting little change, when used as a dielectric layer of a ceramic electronic component such as a laminated ceramic capacitor even under a condition of 150 to 200° C., and has small dielectric losses at 25° C. and 200° C., can be provided.

First claim

The invention claimed is:

1. A dielectric ceramic composition comprising a first component and a second component, wherein:
the dielectric ceramic composition is a sintered compact obtained by mixing a dielectric raw material for the first component obtained by calcining starting materials for the first component and a raw material for the second component, and firing them;
the first component comprises: an oxide of Ca in a content of 0 to 35.85 mol % in terms of CaO; an oxide of Sr in a content of 0 to 47.12 mol % in terms of SrO; an oxide of Ba in a content of 0 to 51.22 mol % in terms of BaO; an oxide of Ti in a content of 0 to 17.36 mol % in terms of TiO 2 ; an oxide of Zr in a content of 0 to 17.36 mol % in terms of ZrO 2 ; an oxide of Sn in a content of 0 to 2.60 mol % in terms of SnO 2 ; an oxide of Nb in a content of 0 to 35.32 mol % in terms of Nb 2 O 5 ; an oxide of Ta in a content of 0 to 35.32 mol % in terms of Ta 2 O 5 ; and an oxide of V in a content of 0 to 2.65 mol % in terms of V 2 O 5 , at the specified content based on the total number of moles of the first component in terms of the above oxides;
the first component comprises at least one selected from the oxide of Ca, the oxide of Sr, and the oxide of Ba, at least one selected from the oxide of Ti and the oxide of Zr, and at least one selected from the oxide of Nb and the oxide of Ta; and wherein, based on a total number of moles of the first component in terms of the above oxides, a total content of the oxide of Ca in terms of CaO, the oxide of Sr in terms of SrO, and the oxide of Ba in terms of BaO is 48.72 to 51.22 mol %; a total content of the oxide of Ti in terms of TiO 2 , the oxide of Zr in terms of ZrO 2 , and the oxide of Sn in terms of SnO 2 is 15.97 to 17.36 mol %; and a total content of the oxide of Nb in terms of Nb 2 O 5 , the oxide of Ta in terms of Ta 2 O 5 , and the oxide of V in terms of V 2 O 5 is 31.42 to 35.31 mol %; and
the dielectric ceramic composition comprises at least an oxide of Mn in a content of more than 0% by mass and 3.5% by mass or less in terms of MnO with respect to the total mass of the first component in terms of the above oxides as the second component.

2. A dielectric ceramic composition comprising a first component and a second component, wherein
the dielectric ceramic composition is a sintered compact obtained by mixing a dielectric raw material for the first component obtained by calcining starting materials for the first component and a raw material for the second component, and firing them;
the dielectric ceramic composition comprises a compound represented by Formula (1):
A a M 1 b M 2 c O d   (1)

wherein A is represented by Formula (2):
Ba 1-x-y Sr x Ca y   (2),

wherein 0≤x≤0.920 and 0≤y≤0.700; M 1 is at least one selected from Ti and Zr, and optionally Sn; and M 2 is at least one selected from Nb and Ta, and optionally V; and 5.70≤a≤6.30, 1.90≤b≤2.10, 7.20≤c≤8.80, and 27.45≤d≤32.50; provided that when Sn is contained, a content of an oxide of Sn in terms of SnO 2 based on a total number of moles of an oxide of Ti in terms of TiO 2 , an oxide of Zr in terms of ZrO 2 , and the oxide of Sn in terms of SnO 2 is 15 mol % or less; and when V is contained, a content of an oxide of V in terms of V 2 O 5 based on a total number of moles of an oxide of Nb in terms of Nb 2 O 5 , an oxide of Ta in terms of Ta 2 O 5 , and the oxide of V in terms of V 2 O 5 is 7.5 mol % or less, as the first component; and
the dielectric ceramic composition comprises an oxide of Mn in a content of more than 0% by mass and 3.5% by mass or less in terms of MnO with respect to the total mass of the compound represented by the Formula (1) in terms of the above oxides as the second component.

3. A dielectric ceramic composition comprising a first component and a second component, wherein:
the dielectric ceramic composition is a sintered compact obtained by mixing a dielectric raw material for the first component obtained by calcining starting materials for the first component and a raw material for the second component, and firing them;
the dielectric ceramic composition comprises a compound represented by Formula (3):
α·Ca η1 M 3 θ1 M 4 ϕ1 O ω1 -β·Sr η2 M 3 θ2 M 4 ϕ2 O ω2 -γ·Ba η3 M 3 θ3 M 4 ϕ3 O ω3   (3)

wherein η 1 , η 2 , and η 3 are each independently a value within a range of 5.70 to 6.30; θ1, θ2, and θ3 are each independently a value within a range of 0.95 to 1.05; ϕ1, ϕ2, and ϕ3 are each independently a value within a range of 0.90 to 1.10; ω1, ω2, and ω3 are each independently a value within a range of 27.45 to 32.50; M 3 is represented by Formula (4): Ti 2-ρ-σ Zr ρ Sn σ (4), wherein 0≤ρ≤2.0 and 0≤σ≤0.3; M 4 is represented by Formula (5): Nb 8-π-ϕ Ta π V ϕ (5), wherein 0≤π≤8.0 and 0≤ϕ≤0.6; α, β, and γ satisfy α+β+γ=1.00; and wherein, when an arbitrary point on a ternary composition diagram is expressed as (α, β, γ), the compound exists in a region surrounded by line segments joining point A=(0.05, 0.95, 0.00), point B=(0.70, 0.30, 0.00), point C=(0.70, 0.00, 0.30), point D=(0.00, 0.00, 1.00), and point E=(0.00, 0.90, 0.10), as the first component; and
the dielectric ceramic composition comprises an oxide of Mn in a content of more than 0% by mass and 3.5% by mass or less in terms of MnO based on a mass of the compound existing in the region surrounded by the line segments joining the point A, the point B, the point C, the point D, and the point E on the ternary composition diagram as the second component.

4. The dielectric ceramic composition according to claim 3 , wherein the first component is a compound existing in a region surrounded by the line segments joining point A′=(0.05, 0.95, 0.00), point B′=(0.60, 0.40, 0.00), point C′=(0.70, 0.20, 0.10), point D′=(0.70, 0.10, 0.20), point E′=(0.55, 0.00, 0.45), point F′=(0.40, 0.00, 0.60), point G′=(0.10, 0.10, 0.80), point H′=(0.00, 0.00, 1.00), point I′=(0.00, 0.40, 0.60), point J′=(0.20, 0.40, 0.40), point K′=(0.00, 0.70, 0.30), and point L′=(0.00, 0.90, 0.10) in the ternary composition diagram.

5. The dielectric ceramic composition according to any one of claims 1 , 2 , and 3 , comprising the oxide of Mn and an oxide of D, wherein D is at least one selected from Li, Mg, Si, Cr, Al, Fe, Co, Ni, Cu, Zn, Ga, Ge, In, W, Mo, Y, Hf, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, as the second component.

6. The dielectric ceramic composition according to any one of claims 1 , 2 , and 3 , having a tungsten bronze-type crystal phase.

7. The dielectric ceramic composition according to claim 1 , wherein a dielectric constant at 25° C. is 100 or more.

8. The dielectric ceramic composition according to claim 7 , wherein the dielectric constant at 25° C. is 200 or more.

9. The dielectric ceramic composition according to claim 8 , wherein the dielectric constant at 25° C. is 300 or more.

10. The dielectric ceramic composition according to claim 1 , wherein a change rate of electrostatic capacity in a temperature range of −55° C. to 200° C. is in a range of −50% to 50%.

11. The dielectric ceramic composition according to claim 10 , wherein a change rate of the electrostatic capacity in a temperature range of −55° C. to 200° C. is in a range of −33% to 22%.

12. The dielectric ceramic composition according to claim 1 , wherein a dielectric loss (tan δ) at 25° C. is 10% or less, and a dielectric loss (tan δ) at 200° C. is 10% or less.

13. A ceramic electronic component comprising a dielectric layer formed of the dielectric ceramic composition according to claim 1 , and an electrode layer containing a base metal as a conductive component.

Assignees

• Shoei Chemical Ind Co

Inventors

• Nomura Takeshi
• Nemoto Atsushi
• Sasaki Yukari
• Takemoto Kazuhiko
• KINOSHITA Naomi
• Takahashi Yumi

Classifications

• C04B35/499

  containing also titanates · CPC title

• H01B3/12 Primary

  ceramics · CPC title

• H01G4/30

  Stacked capacitors (H01G4/33 takes precedence) · CPC title

• H01G4/12

  Ceramic dielectrics {(H01G4/085 takes precedence)} · CPC title

• C04B2235/3208

  Calcium oxide or oxide-forming salts thereof, e.g. lime · CPC title