JP3467876B2 - Dielectric porcelain composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] The present invention relates to a material for a dielectric resonator or the like.
The present invention relates to a dielectric porcelain composition suitable as the above. [0002] 2. Description of the Related Art In recent years, microwave circuits
With integration, small and high-performance dielectric resonators are required
ing. Dielectric magnet used in such a dielectric resonator
The container composition has a relative dielectric constant ε_rIs large, and no-load Q
Large, temperature coefficient τ of resonance frequency_fIs small
Characteristics are required. As such a dielectric ceramic composition, Ba is used.
O-TiO_Two-Nd_TwoO_ThreeBased dielectric porcelain composition
[Ber. Dt. Keram. Ges., 55 (1978) Nr. 7;
-35406] or BaO-TiO._Two-N
d_TwoO_Three-Bi_TwoO_ThreeSystem (Japanese Patent Application Laid-Open No. 62-72558)
Information) has been proposed. [0004] Recently, a laminated ceramic laminated with a dielectric ceramic composition has been proposed.
Capacitors and multilayer dielectric resonators have been developed.
Layering by simultaneous firing of the porcelain composition and internal electrodes
Is being done. However, the dielectric porcelain composition is
Internal electrode because firing temperature is as high as 1300 ° C to 1400 ° C
It is difficult to perform simultaneous firing with
Palladium that can withstand high temperatures as an electrode material
(Pd) and platinum (Pt). This
Therefore, inexpensive silver (Ag) and silver-palladium
1200 ° C. using aluminum (Ag-Pd) and copper (Cu)
Dielectric ceramic compositions that can be co-fired at the following low temperatures are required
Have been. [0005] An object of the present invention is to provide a material for a dielectric resonator or the like.
Excellent characteristics, especially high dielectric constant, large unloaded Q
Has a characteristic that the temperature change of the resonance frequency is small,
Moreover, even when fired at a low temperature, the dielectric magnet has good sinterability.
To provide a container composition. [0006] According to the present invention, the main component is a composition.
Formula, xBaO-yTiO₂-ZNd₂O₃-TSm₂O
₃-WBi₂O₃(Where 0.1 ≦ x ≦ 0.2, 0.5
≦ y ≦ 0.8, 0.01 ≦ z ≦ 0.2, 0 ≦ t ≦ 0.
2, 0.005 <w <0.05, x + y + z + t + w =
It is one. ) Is a dielectric porcelain composition represented by
, Titanium, neodymium, samarium, bismuth and
Calcined powder composed of oxygen and PbO, ZnO and
And B₂O₃Powder and GeO composed of
₂andLi ₂ CO ₃ And 85 in an oxygen-containing gas atmosphere.
Dielectric obtained by firing at 0 ° C to 1100 ° C
A porcelain composition, wherein the auxiliary component gas is based on the main component.
The content a (% by weight) of the lath powder is 1 ≦ a ≦ 25;
eO₂The content b (% by weight) of 0.5 ≦ b ≦ 10 and
The Li ₂ CO ₃ Arise fromLi₂O content c (weight
%) Is 0.04 ≦ c ≦ 4.
It relates to a porcelain composition. According to the present invention, the composition formula xBaO-yTi
O_Two-ZNd_TwoO_Three-TSm_TwoO_Three-WBi_TwoO_ThreeIn table
PbO and Zn as sub-components in the dielectric ceramic composition to be
O and B_TwoO_ThreeGlass powder composed of and G
eO_TwoAnd Li_TwoBy incorporating O, low-temperature firing
High dielectric constant, large no-load Q, resonance frequency
Porcelain set with characteristics of small temperature change of number
A product can be obtained. In the present invention, the molar fraction of BaO is excessively high.
If it is too large, it will not resonate, if it is too small
, The dielectric constant and the no-load Q become smaller. TiO_TwoMole of
If the fraction is too large, the temperature coefficient of the resonance frequency will
If it is too large and too small, the dielectric constant will be small.
You. Nd_TwoO_ThreeIf the mole fraction of
If the power factor and the no-load Q become too small,
The temperature coefficient of the resonance frequency increases. Sm_TwoO_ThreeMole of
If the fraction is too large, the dielectric constant and unloaded Q
It becomes. Bi_TwoO_ThreeIs too large
Is when the dielectric constant and unloaded Q are too small and too small
, The temperature coefficient of the resonance frequency increases. Further, in the present invention, the sub
Components PbO, ZnO and B_TwoO_ThreeGala consisting of
Powder content a (% by weight) and GeO_TwoContent of
When b (% by weight) is excessively large, the no-load Q is small.
Become Li_TwoO content c (% by weight) is excessively large
In such a case, no resonance occurs. In addition, PbO, ZnO and
And B_TwoO_ThreePowder and GeO composed of_Two
If the content b (% by weight) is too small or zero
Makes it difficult to fire at 1200 ° C. or lower at low temperatures. Li_Two
By including O, the sintering temperature is further lowered,
Ag internal electrodes can be easily formed. Therefore,
Secondary components PbO, ZnO and B_TwoO_ThreeMoth composed of
Lath powder content a (% by weight) and GeO_TwoContaining
Quantity b (% by weight) and Li_TwoThe content c (% by weight) of O is
It is set in the above range. Secondary components PbO, ZnO and B
_TwoO_ThreeGlass powder composed of PbO, Z
nO and B_TwoO_ThreeThe composition ratio of is not particularly limited,
When the content of ZnO is excessively large, the softening point of the glass
Rises, making low-temperature sintering difficult.
The content of ZnO is preferably 50% by weight or less. Preferred method for producing the dielectric ceramic composition of the present invention
An example will be described below. Barium carbonate, titanium oxide, acid
Of neodymium fluoride, samarium oxide and bismuth oxide
Wet raw materials with water, alcohol, etc.
Mix. Subsequently, after removing water, alcohol, etc., the powder
Crushed under an oxygen-containing gas atmosphere (for example, an air atmosphere).
Calcinate at 000-1300 ° C for about 1-5 hours. this
The calcined powder obtained in this way and the subcomponents PbO, ZnO and
And B_TwoO_ThreeGlass powder composed of GeO_Two, Li
_TwoCO_ThreeIs wet-mixed and ground with a solvent such as alcohol.
I do. Then, after removing water, alcohol, etc.
Mixed with organic binder such as Nyl alcohol
, Drying, pulverization, pressure molding (pressure 100-1000K
g / cm^Two Degree). The resulting molded product is treated with an acid such as air.
Baking at 850 ° C to 1100 ° C in an atmosphere containing nitrogen gas
As a result, a dielectric ceramic composition represented by the above composition formula is obtained.
Can be [0011] The dielectric ceramic composition thus obtained
Is processed to an appropriate shape and size if necessary, or
Is a sheet molding and sheeting by a doctor blade method or the like.
And electrodes to form a dielectric resonator and a dielectric substrate.
It can be used as a material for plates, laminated elements, and the like. In addition, barium, titanium, neodymium, and sama
Lium, bismuth, lead, zinc, boron, germanium,
As a raw material of lithium, BaCO_Three, TiO_Two, Nd
_TwoO _Three, Sm_TwoO_Three, Bi_TwoO_Three, PbO, ZnO, B
_TwoO_Three, GeO_Two, Li_TwoCO_ThreeBesides, oxidation during firing
Nitrate, hydroxide and the like can be used. [0013] The following examples and comparative examples illustrate the present invention.
This will be described more specifically. Example 1 Barium carbonate powder (BaCO_Three) 0.13 mol, oxide
Tan powder (TiO_Two) 0.69 mol, neodymium oxide powder
(Nd_TwoO_Three) 0.16 mol, bismuth oxide powder (Bi
_TwoO_Three) 0.02 mol to a ball mill together with ethanol
And wet mixed for 12 hours. After desolvating the solution, pulverize,
Calcination was performed at 1250 ° C. in an air atmosphere. Also, lead oxide powder
(PbO) 84wt%, zinc oxide powder (ZnO) 7wt
% And boron oxide powder (B_TwoO_Three) Consists of 9wt%
Was prepared by a conventional method. Obtained above
PbO, ZnO and B_TwoO_ThreeFrom
Glass powder A2wt% to be formed and germanium oxide
Powder (GeO_Two) 3wt% and lithium carbonate powder
(Li_TwoCO_Three) 1 wt% (Li_Two0.4wt in O conversion
% And added to a ball mill together with ethanol.
Wet-mixed. After desolvating the solution, pulverize and pulverize the solution.
After adding an appropriate amount of polyvinyl alcohol solution and drying,
Form into pellets of 12mmφ and 4mmt thickness, air atmosphere
It was calcined at 945 ° C. for 2 hours under an atmosphere. [0014] The porcelain composition obtained in this way is 7 mm in diameter.
φ, processed into a size of about 3mmt, dielectric resonance
Measured at the resonance frequency (3 to 6 GHz)
Temperature coefficient of the no-load Q, relative permittivity and resonance frequency
I did. Table 2 shows the results. Examples 2 to 21 and Comparative Examples 1 to 16 Barium carbonate, titanium oxide, neodymium oxide of Example 1,
The mixing ratio of samarium oxide and bismuth oxide
PbO, ZnO and B_TwoO_ThreeComposed of
Type of glass powder (glass powder B: 80 wt% PbO,
ZnO10wt%, B_TwoO_Three10wt%) and auxiliary components
Same as Example 1 except that the addition amount was changed as shown in Table 1.
To produce a dielectric ceramic composition, and the characteristics were measured. So
Table 2 shows the results. [0016] [Table 1][0017] [Table 2][0018] According to the present invention, the relative permittivity ε_rIs large
And the no-load Q value is large, and the temperature of the resonance frequency
Coefficient τ_fCan provide a dielectric ceramic composition having a small
Wear. In addition, low-temperature sintering is possible, and Ag, Ag-P
Dielectric ceramics that can be laminated using d, Cu, etc. as internal electrodes
A composition can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01B 3/12 C04B 35/46 H01G 4/12 H01P 7/10

Claims (1)

(57) [Claim 1] The main component is a composition formula, xBaO-yTiO ₂
-ZNd ₂ O ₃ -tSm ₂ O ₃ -wBi ₂ O ₃ (wherein,
0.1 ≦ x ≦ 0.2, 0.5 ≦ y ≦ 0.8, 0.01 ≦
z ≦ 0.2, 0 ≦ t ≦ 0.2, 0.005 <w <0.0
5, x + y + z + t + w = 1. ), A calcined powder composed of barium, titanium, neodymium, samarium, bismuth and oxygen, glass powder composed of PbO, ZnO and B ₂ O ₃ as auxiliary components, and GeO ₂ and Li ₂ CO _3, which are obtained by firing at 850 ° C. to 1100 ° C. in an oxygen-containing gas atmosphere, wherein the content a of the sub-component glass powder with respect to the main component a (weight %) Is 1 ≦ a ≦ 25, the content b (% by weight) of the GeO ₂ is 0.5 ≦ b ≦ 10, and the LiO ₂ is produced from the Li ₂ CO _3.
Jill Li ₂ O content c (wt%) is 0.04 ≦ c ≦ 4
A dielectric porcelain composition, characterized in that: