Claims
- 1. A dielectric resonator, comprising:
- a dielectric ceramic body obtained by firing a dielectric ceramic composition produced By (i) preparing a main ceramic composition comprising SaO, TiO.sub.2 and Re.sub.2 O.sub.3 as major components, Re representing at least one rare earth metal, wherein a mixture of starting materials which gives said main ceramic composition is calcined at a temperature not lower than 1050.degree. C., (ii) finely pulverizing said calcined mixture to provide a calcined ceramic powder having an average grain size of not larger than 0.8 .mu.m, and (iii) adding a secondary component comprising B.sub.2 O.sub.3 powder or a glass powder containing B.sub.2 O.sub.3 to said calcined ceramic powder or said mixture of starting materials prior to calcining; and
- a conductor pattern formed by co-firing with said dielectric ceramic body such that said conductor pattern is embedded in said dielectric ceramic body.
- 2. The dielectric resonator of claim 1, wherein said B.sub.2 O.sub.3 is contained in said dielectric ceramic composition in an amount of 0.1-7.5 parts by weight per 100 parts by weight of the main ceramic composition.
- 3. A dielectric filter comprising a plurality of dielectric resonators, each dielectric resonator comprising:
- a dielectric ceramic body obtained by firing a dielectric ceramic composition produced by (i) preparing a main ceramic composition comprising BaO, TiO.sub.2 and Re.sub.2 O.sub.3 as major components, Re representing at least one rare earth metal, wherein a mixture of starting materials which gives said main ceramic composition is calcined at a temperature not lower than 1050.degree. C., (ii) finely pulverizing said calcined mixture to provide a calcined ceramic powder having an average grain size of not larger than 0.8 .mu.m, and (iii) adding a secondary component comprising B.sub.2 O.sub.3 powder or a glass powder containing B.sub.2 O.sub.3 to said calcined ceramic powder or said mixture of starting materials prior to calcining; and
- a conductor pattern formed by co-firing with said dielectric ceramic body such that said conductor pattern is embedded in said dielectric ceramic body.
- 4. The dielectric resonator of claim 1, wherein said conductor pattern consists of Ag or of an alloy containing Ag as a major component, said dielectric ceramic body having a sintering temperature of not greater than 962.degree. C.
- 5. The dielectric resonator of claim 4, wherein said sintering temperature is not greater than 950.degree. C.
- 6. The dielectric resonator of claim 5, wherein said sintering temperature is not greater than 900.degree. C.
- 7. The dielectric resonator of claim 1, wherein said average grain size is within a range of 0.1-0.8 .mu.m.
- 8. The dielectric resonator of claim 1, wherein said average grain size is not larger than 0.7 .mu.m.
- 9. The dielectric resonator of claim 1, wherein said dielectric resonator has an unloaded Q value within a range of 500-300, as evaluated at 3 GHz.
- 10. The dielectric filter of claim 3, wherein said conductor pattern consists of Ag or of an alloy containing Ag as a major component, said dielectric ceramic body having a sintering temperature of not greater than 962.degree. C.
- 11. The dielectric filter of claim 10, wherein said sintering temperature is not greater than 950.degree. C.
- 12. The dielectric filter of claim 11, wherein said sintering temperature is not greater than 900.degree. C.
- 13. The dielectric filter of claim 3, wherein said average grain size is within a range of 0.1-0.8 .mu.m.
- 14. The dielectric filter of claim 3, wherein said average grain size is not larger than 0.7.mu.m.
- 15. The dielectric filter of claim 3, wherein said B.sub.2 O.sub.3 is contained in said dielectric ceramic composition in an amount of 0.1-7.5 parts by weight by 100 parts by weight of the main ceramic composition.
- 16. The dielectric filter of claim 3, wherein said dielectric filter has an unloaded Q value within a range of 500-1300, as evaluated at 3 GHz.
- 17. The dielectric resonator of claim 1, wherein said average grain size is not larger than 0.6 .mu.m.
- 18. The dielectric filter of claim 3, wherein said average grain size is not larger than 0.6 .mu.m.
Priority Claims (3)
Number |
Date |
Country |
Kind |
3-276587 |
Sep 1991 |
JPX |
|
4-092180 |
Mar 1992 |
JPX |
|
4-276597 |
Sep 1992 |
JPX |
|
Parent Case Info
This is a Division of application Ser. No. 07/950,664 filed Sep. 25, 1992, now U.S. Pat. No. 5,292,694.
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Divisions (1)
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Number |
Date |
Country |
Parent |
950664 |
Sep 1992 |
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