Dielectric ceramic composition and ceramic electronic...

Details Dielectric ceramic composition and ceramic electronic... Dielectric ceramic composition and ceramic electronic...

1999-02-26

2001-11-13

Sample, David R. (Department: 1755)

Compositions: ceramic

Ceramic compositions

Glass compositions, compositions containing glass other than...

C501S063000, C501S064000, C501S065000, C501S066000, C501S067000, C501S068000, C501S069000, C501S070000

Reexamination Certificate

active

06316374

ABSTRACT:

BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a dielectric ceramic composition and a ceramic electronic element produced from the same. More particularly, the present invention relates to a dielectric ceramic composition which has a high value of Q (hereinafter referred to as “high Q”) in a high-frequency region such as a microwave region or a millimeter wave region and which provides a glass ceramic material useful for a low-temperature-firable dielectric ceramic composition for temperature compensation, and to a ceramic electronic element made from the composition, such as a monolithic capacitor.
BACKGROUND ART
As mobile communication devices are operated in a higher-frequency region and at higher speed, a dielectric ceramic must have a higher Q in the high-frequency region. Conventionally, a resonator material having a composition such as Ba—Nd—Pb—Ti—O has been known as a material having a high Q in a high-frequency region, and an alumina-borosilicate glass ceramic substrate has been known as a low-temperature-sinterable material.
However, although such a resonator material has a high Q, sintering thereof at a temperature as low as 1050° C. or lower is difficult and does not allow formation of an electrode from a material such as Ag or Cu. In addition, a low-temperature-sinterable alumina glass ceramic has a disadvantageously low Q.
SUMMARY OF THE INVENTION
In view of the foregoing, an object of the present invention is to provide a novel dielectric ceramic composition which can be sintered at low temperature and has a high Q and a good temperature-dependent characteristic of capacitance in the high-frequency region. Another object of the present invention is to provide a ceramic electronic element produced from the same.
Accordingly, in a first aspect of the present invention, there is provided a dielectric ceramic composition comprising glass and at least one of an Si—Mg—Al—O ceramic and TiO
2
.
Preferably, in the dielectric ceramic composition according to the present invention, the compositional proportions of the three components based on wt. % of (glass, Si—Mg—Al—O ceramic, TiO
2
) fall within a polygon formed by connecting points A(
100
,
0
,
0
), B(
30
,
70
,
0
), and C(
30
,
0
,
70
) in the ternary diagram of FIG.
1
.
More preferably, the compositional proportions of the three components based on wt. % of (glass, Si—Mg—Al—O ceramic, TiO
2
) fall within a polygon formed by connecting points A′(
100
,
0
,
0
), B′(
30
,
70
,
0
), C′(
30
,
30
,
40
), and D′(
80
,
0
,
20
) in the ternary diagram of FIG.
1
.
Still more preferably, the compositional proportions of the three components based on wt. % of (glass, Si—Mg—Al—O ceramic, TiO
2
) fall within a polygon formed by connecting points A″(
100
,
0
,
0
), B″(
40
,
60
,
0
), C″(
30
,
65
,
5
), D″(
30
,
50
,
20
), and E″(
85
,
0
,
15
) in the ternary diagram of FIG.
1
.
Furthermore, the glass is preferably silicate glass in the dielectric ceramic composition according to the present invention.
Preferably, the silicate glass comprises SiO
2
and at least one of B
2
O
3
and K
2
O, wherein the compositional proportions of the three components based on wt. % of (SiO
2
, B
2
O
3
, K
2
O) fall within a polygon formed by connecting points F(
65
,
35
,
0
), G(
65
,
20
,
15
), H(
85
,
0
,
15
), and I(
85
,
15
,
0
) in the ternary diagram of FIG.
2
.
More preferably, the silicate glass compositional proportions of the three components based on wt. % of (SiO
2
, B
2
O
3
, K
2
O) fall within a polygon formed by connecting points J(
75
,
24
.
5
,
0
.
5
), K(
75
,
22
,
3
), L(
85
,
12
,
3
), and M(
85
,
14
.
5
,
0
.
5
) in the ternary diagram of FIG.
2
.
Preferably, the silicate glass contains, in addition to the mentioned primary components, i.e., SiO
2
and at least one of B
2
O
3
and K
2
O, at least one species selected from among Li
2
O, Na
2
O, MgO, CaO, SrO, BaO, ZnO, Al
2
O
3
, La
2
O
3
, Ta
2
O
5
, Nd
2
O
3
and compounds thereof in an amount of 5 wt. % or less based on 100 wt. % of the entirety of the primary components of the silicate glass.
Furthermore, preferably, in the Si—Mg—Al—O ceramic component of the dielectric ceramic composition according to the present invention, the compositional proportions of the three components based on mol % of (SiO
2
, Al
2
O
3
, MgO) falls within a polygon formed by connecting points N(
100
,
0
,
0
), O(
50
,
50
,
0
), P(
0
,
50
,
50
), and Q(
0
,
0
,
100
) in the ternary diagram of FIG.
3
.
In a second aspect of the present invention, there is provided a ceramic electronic element including a dielectric layer formed from the dielectric ceramic composition according to the present invention.
In a third aspect of the present invention, there is provided a monolithic ceramic capacitor including a dielectric layer formed from the dielectric ceramic composition according to the present invention.


REFERENCES:
patent: 4777092 (1988-10-01), Kawakami et al.
patent: 5024975 (1991-06-01), Hartmann
patent: 5079194 (1992-01-01), Jean et al.
patent: 5141899 (1992-08-01), Jean et al.
patent: 5206190 (1993-04-01), Jean et al.
patent: 5212121 (1993-05-01), Omata et al.
patent: 5242867 (1993-09-01), Lin et al.
patent: 5283210 (1994-02-01), Kata et al.
patent: 5342674 (1994-08-01), Tanai et al.
patent: 5498580 (1996-03-01), Yamade et al.
patent: 5578533 (1996-11-01), Manabe et al.
patent: 5821181 (1998-10-01), Bethke et al.
patent: 5998314 (1999-12-01), Sugimoto et al.

Affiliated with

Also associated with

Rating

Dielectric ceramic composition and ceramic electronic... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Dielectric ceramic composition and ceramic electronic..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Dielectric ceramic composition and ceramic electronic... will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2604094