CN1067360C

CN1067360C - High-dielectric constant microwave-medium ceramics

Info

Publication number: CN1067360C
Application number: CN97118315A
Authority: CN
Inventors: 陈湘明; 杨敬思
Original assignee: Zhejiang University ZJU
Current assignee: Zhejiang University ZJU
Priority date: 1997-09-12
Filing date: 1997-09-12
Publication date: 2001-06-20
Anticipated expiration: 2017-09-12
Also published as: CN1211557A

Abstract

本发明公开的“高介电常数微波介质陶瓷”是微波通讯元器件的关键材料，它是BaO、(Nd_1-xBi_x)₂O₃、TiO₂、(Ta_1-yNb_y)₂O₅组合而成，各成份含量分别为：8.34摩尔%≤BaO≤41.66摩尔%，4.17摩尔%≤(Nd_1-xBi_x)₂O₃≤20.83摩尔%，其中0≤x≤0.15，25.0摩尔%≤TiO₂≤58.33摩尔%，12.5摩尔%≤(Ta_1-yNb_y)₂O₅≤29.17摩尔%，其中0≤y≤1.0，各成分含量百分数之和为100摩尔%。本发明提供的微波介质陶瓷，其介电常数可达80～155，同时具有低损耗与较小的谐振频率温度系数。The "high dielectric constant microwave dielectric ceramic" disclosed by the present invention is the key material of microwave communication components, which are BaO, (Nd _1-x Bi _x ) ₂ O ₃ , TiO ₂ , (Ta _1-y Nb _y ) ₂ O ₅ , the contents of each component are: 8.34 mol% ≤ BaO ≤ 41.66 mol%, 4.17 mol% ≤ (Nd _1-x Bi _x ) ₂ O ₃ ≤ 20.83 mol%, where 0 ≤ x ≤ 0.15, 25.0 Mole % ≤ TiO ₂ ≤ 58.33 mol %, 12.5 mol % ≤ (Ta _1-y Nb _y ) ₂ O ₅ ≤ 29.17 mol %, where 0 ≤ y ≤ 1.0, and the sum of the percentages of each component is 100 mol %. The microwave dielectric ceramic provided by the invention has a dielectric constant up to 80-155, and has low loss and small temperature coefficient of resonance frequency.

Description

High-permittivity microwave medium ceramics

The present invention relates to the microwave-medium ceramics that the microwave device such as dielectric resonator, wave filter in the communication system is used.

In recent years, along with developing rapidly of mobile communication and satellite communication technology, the demand of the microwave-medium ceramics that microwave devices such as dielectric resonator and wave filter are used is just growing.

For microwave-medium ceramics, at first require it that low dielectric loss (high Q value is arranged, Q＞3000 are at applying frequency) and approach zero temperature coefficient of resonance frequency (f＜20ppm/ ℃ of 20ppm/ ℃＜τ, for the lower material series of specific inductivity, f＜10ppm/ ℃ of requirement-10ppm/ ℃＜τ), simultaneously, require the high DIELECTRIC CONSTANT of trying one's best for the needs that satisfy device miniaturization.

Existing microwave-medium ceramics is a principal crystalline phase with uhligite or perovskite-like all mutually generally, though developed a series of microwave-medium ceramics at present, high-k class material (ε＞80) is less for number, even and the highest BaO-Nd of specific inductivity ₂O ₃-TiO ₂Series, its specific inductivity is the highest also can only to reach 90 front and back.In general, its dielectric loss of the material that specific inductivity is big and temperature factor are also bigger.Therefore, 100 specific inductivity once was considered to one threshold that microwave-medium ceramics is difficult to go beyond.This has just limited the expansion of further miniaturization of microwave device and range of application widely.

In view of above-mentioned, the purpose of this invention is to provide a kind of have low-loss and good temperature stability, have the microwave-medium ceramics of high-k simultaneously.

Technical solution of the present invention is: from brand-new angle, be conceived to easily form the BaO-Nd of tungsten bronze(s) ore deposit structure ₂O ₃-TiO ₂-Ta ₂O ₅With BaO-Nd ₂O ₃-TiO ₂-Nb ₂O ₅System proposes a kind of with BaO, (Nd _1-xBi _x) ₂O ₃, TiO ₂, (Ta _1-yNb _y) ₂O ₅The compound solid solution body microwave-medium ceramics of the tungsten bronze structure that is combined into, the content of each composition is respectively: the content of establishing BaO is 8.34 moles of %≤m≤41.66 mole % of m

(Nd _1-xBi _x) ₂O ₃Content be n 4.17 moles of %≤n≤20.83 mole %, wherein 0≤x≤0.15

TiO ₂Content be 25.0 moles of %≤p≤58.33 mole % of p

(Ta _1-yNb _y) ₂O ₅Content be q 12.5 moles of %≤q≤29.17 mole %, wherein 0≤y≤1.0

M+n+p+q=100 mole %.

The preferred content of each composition is: m=33.34 mole %, n=8.33 mole %, p=33.33 mole %, q=25.0 mole %, x=0.05, y=0.25.

The high-permittivity microwave medium ceramics of invention can be prepared from as follows.

At first, with purity be BaCO more than 99.9% ₃, Nd ₂O ₃, Bi ₂O ₃, TiO ₂, Ta ₂O ₅And Nb ₂O ₅Mix 24 hours (solvent is a distilled water) with the wet ball-milling method according to a certain percentage, the oven dry back is given in 1100～1250 ℃, air atmosphere and being burnt 3 hours.Then, in giving the burning powder, after interpolation binding agent and the granulation, be formed in 1000kg/cm by uniaxial tension ²Pressure under prepare the ceramic body of diameter 12mm, thickness 3～6mm, at last in 1300～1450 ℃, air atmosphere sintering 3 hours to prepare required microwave-medium ceramics.

Table 1 shows several specific exampless and the microwave dielectric property thereof that constitutes each component content of the present invention.

As known from Table 1, in ceramic systems of the present invention, along with BaO and Ta ₂O ₅The increase and the Nd of content (m, q) ₂O ₃With TiO ₂The minimizing of content (n, p), DIELECTRIC CONSTANT are tending towards increasing and Qf value (Q is that quality factor are the inverse of dielectric loss, and f is a resonant frequency) is tending towards reducing, temperature coefficient of resonance frequency τ f is tending towards increase simultaneously.

High-permittivity microwave medium ceramics provided by the invention, its specific inductivity be up to 80～155, and have low-loss and less temperature coefficient of resonance frequency simultaneously, and the specific inductivity of particularly having broken through microwave-medium ceramics is generally less than 100 " threshold ".And utilize high-permittivity microwave medium ceramics provided by the invention, can make the further miniaturization of microwave devices such as dielectric resonator and wave filter become possibility.Simultaneously, pottery provided by the invention also can be applicable to radio ceramics electrical condenser or temperature compensating ceramic capacit etc.Therefore, the present invention has great value industrial.

Table 1

m moI％)	n (moI％)	p (moI％)	q (nol％)	x	y	ε	Qf (GHz)	τr (ppm/℃)
m moI％)	n (moI％)	p (moI％)	q (nol％)	x	y	ε	Qf (GHz)	τr (ppm/℃)	8.34	20.83	58.33	12.50	0	0	81	4800	12
16.66	16.67	50.00	16.67	0	0	90	4600	15	8.34	20.83	58.33	12.50	0	0	81	4800	12
16.66	16.67	50.00	16.67	0	0	90	4600	15	25.00	12.50	41.67	20.83	0	0	100	3700	16
33.34	8.33	33.33	25.00	0	0	135	3500	18	25.00	12.50	41.67	20.83	0	0	100	3700	16
33.34	8.33	33.33	25.00	0	0	135	3500	18	41.66	4.17	25.00	29.17	0	0	155	3200	20
									41.66	4.17	25.00	29.17	0	0	155	3200	20
									25.00	12.50	41.67	20.83	0	0.1	95	3900	12
33.34	8.33	33.33	25.00	0	0.25	105	4500	10	25.00	12.50	41.67	20.83	0	0.1	95	3900	12
33.34	8.33	33.33	25.00	0	0.25	105	4500	10	41.66	4.17	25.00	29.17	0	0.5	133	3500	10
41.66	4.17	25.00	29.17	0	1.0	98	3100	19	41.66	4.17	25.00	29.17	0	0.5	133	3500	10
41.66	4.17	25.00	29.17	0	1.0	98	3100	19
8.34	20.83	58 33	12.50	0.15	0	98	5000	6
8.34	20.83	58 33	12.50	0.15	0	98	5000	6	16.66	16.67	50.00	16.67	0.10	0	102	4500	8
25.00	12.50	41.67	20.83	0.08	0.1	100	4200	9	16.66	16.67	50.00	16.67	0.10	0	102	4500	8
25.00	12.50	41.67	20.83	0.08	0.1	100	4200	9	33.34	8.33	33.33	25.00	0.05	0.25	132	5500	9
41.66	4.17	25.00	29.17	0.03	0.5	151	4500	12	33.34	8.33	33.33	25.00	0.05	0.25	132	5500	9

Claims

1. high-permittivity microwave medium ceramics is characterized in that it is with BaO, (Nd _1-xBi _x) ₂O ₃, TiO ₂, (Ta _1-yNb _y) ₂O ₅The compound solid solution body of the tungsten bronze structure that combines, the content of each composition is respectively: the content of establishing BaO is 8,34 moles of %≤m≤41.66 mole % of m

TiO ₂Content be 25.0 moles of %≤p≤58.33 mole % of p

M+n+p+q=100 mole %.

2. by the described microwave-medium ceramics of claim 1, it is characterized in that the content of each composition is: m=33.34 mole %, n=8.33 mole %, p=33.33 mole %, q=25.0 mole %, x=0.05, y=0.25.