CN107010952A - A kind of gallate ultralow dielectric microwave dielectric ceramic - Google Patents

A kind of gallate ultralow dielectric microwave dielectric ceramic Download PDF

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CN107010952A
CN107010952A CN201710268595.2A CN201710268595A CN107010952A CN 107010952 A CN107010952 A CN 107010952A CN 201710268595 A CN201710268595 A CN 201710268595A CN 107010952 A CN107010952 A CN 107010952A
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dielectric ceramic
binding agent
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方维双
陈进武
李纯纯
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Guilin University of Technology
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Abstract

The invention discloses a kind of gallate temperature-stable ultralow dielectric microwave dielectric ceramic Li3W2Ga3O12And preparation method thereof.(1) it is Li more than 99.9% (percentage by weight) by purity2CO3、WO3And Ga2O3Starting powder press Li3W2Ga3O12Composition weigh dispensing；(2) by step (1) raw material wet ball-milling mix 12 hours, ball-milling medium is distilled water, after drying in 1100 DEG C of air atmospheres pre-burning 6 hours；(3) after binding agent is added in powder made from step (2) and is granulated, re-compacted shaping is finally sintered 4 hours in 1150~1200 DEG C of air atmospheres；Described binding agent uses mass concentration for 5% poly-vinyl alcohol solution, and the addition of polyvinyl alcohol accounts for the 3% of powder gross mass.Ceramics prepared by the present invention are sintered well below 1200 DEG C, and dielectric constant reaches 9.6~10.3, and its quality factor q f values are up to 81000 102000GHz, and temperature coefficient of resonance frequency is small, industrially there is great application value.

Description

A kind of gallate ultralow dielectric microwave dielectric ceramic
Technical field
The present invention relates to dielectric ceramic material, more particularly to for manufacturing ceramic substrate, the resonance that microwave frequency is used Dielectric ceramic material of microwave device such as device and wave filter and preparation method thereof.
Background technology
Microwave dielectric ceramic refers to be applied in microwave frequency band (mainly UHF and SHF frequency ranges) circuit as dielectric material And the ceramics of one or more functions are completed, it is widely used as resonator, wave filter, dielectric substrate and medium in modern communication The components such as wave circuit, are the key foundation materials of modern communication technology, in portable mobile phone, automobile telephone, nothing There is highly important application in terms of rope phone, television satellite recipient and military radar, in the small-sized of modern communication instrument Change, it is integrated during just playing increasing effect.
Applied to the dielectric ceramic of microwave frequency band, the requirement of following dielectric property should be met：(1) seriation permittivity εr To adapt to the requirement of different frequency and different application occasion；(2) high quality factor q value or low dielectric loss tan δ are to reduce Noise, typically requires Qf >=3000GHz；(3) the temperature coefficient τ of resonant frequencyfIt is as small as possible to ensure heat that device has had Stability, general -10ppm/ DEG C of requirement≤τf≤+10ppm/℃.Just had tried to electricity from late 1930s in the world Dielectric material is applied to microwave technology, and prepares TiO2Microwave dielectric filter, but its temperature coefficient of resonance frequency τfIt is too big and Can not be practical.Since the seventies in last century, the large-scale development to medium ceramic material is started, according to relative Jie Electric constant εrSize with using frequency range difference, generally the microwave-medium ceramics for having been developed that He developing can be divided into 4 Class.
(1) ultralow dielectric microwave dielectric ceramic, main representative is Al2O3-TiO2、Y2BaCuO5、MgAl2O4With Mg2SiO4Deng its εr≤ 20, quality factor q × f >=50000GHz, τf≤10ppm/℃.It is mainly used in microwave base plate and height Hold microwave device.
(2) low εrWith the microwave dielectric ceramic of high q-factor, mainly BaO-MgO-Ta2O5,BaO-ZnO-Ta2O5Or BaO- MgO-Nb2O5,BaO-ZnO-Nb2O5System or the hybrid system MWDC materials between them.Its εr=20~35, Q=(1~2) ×104(under f >=10GHz), τf≈0.It is mainly used in humorous as medium in the microwave communication equipments such as f >=8GHz direct broadcasting satellite Shake device.
(3) medium εrWith the microwave dielectric ceramic of Q values, it is mainly with BaTi4O9、Ba2Ti9O20(Zr, Sn) TiO4Etc. for The MWDC materials of base, its εr=35~45, Q=(6~9) × 103(under f=3~-4GHz), τf≤5ppm/℃.It is main to use Dielectric resonator device is used as in the microwave military radar and communication system in 4~8GHz frequency ranges.
(4) high εrAnd the relatively low microwave dielectric ceramic of Q values, it is mainly used in civilian movement in 0.8~4GHz frequency ranges and leads to News system, this is also the emphasis of microwave dielectric ceramic research.Since the eighties, Kolar, Kato et al. have found and have studied in succession Perovskite-like tungsten bronze type BaO-Ln2O3—TiO2Serial (Ln=La, Sm, Nd or Pr etc., abbreviation BLT systems), composite perofskite Structure C aO-Li2O—Ln2O3—TiO2Series, lead base series material, Ca1-xLn2x/3TiO3It is contour εrMicrowave dielectric ceramic, Wherein BaO-Nd of BLT systems2O3—TiO2Material dielectric constant reaches 90, lead base series (Pb, Ca) ZrO3Dielectric constant reaches To 105.
The sintering temperature of the above material system is generally greater than 1300 DEG C, it is impossible to directly with the low-melting-point metal such as Ag and Cu Burn altogether and form multilayer ceramic capacitor.In recent years, with LTCC Technology (Low Temperature Co-fired Ceramics, LTCC) development and microwave multilayer device development requirement, researcher both domestic and external is to some low fever's system materials Material has carried out extensive exploration and research, mainly using devitrified glass or glassceramic composite system, because of low melting point glass Glass mutually has of a relatively high dielectric loss, and the presence of glass phase substantially increases the dielectric loss of material.Therefore develop without glass Low fever's microwave dielectric ceramic materials of glass phase are the emphasis of current research.
Explore with develop it is new can be during low fever's microwave dielectric ceramic material, the low Li bases of intrinsic sintering temperature The material systems such as compound, Bi based compounds, tungstates system compound and tellurate system compound get the attention with Research, but be due to three performance indications (ε of microwave dielectric ceramicrWith Qf and τf) between be the relation mutually restricted (see text Offer：Restricting relation between microwave dielectric ceramic materials dielectric properties, Zhu Jianhua, Liang Fei, Wang Xiaohong, Lv Wenzhong, electronic component with Material, phase March the 3rd in 2005), meet three performance requirements and the single-phase microwave-medium ceramics of low temperature sintering are considerably less, it is main If their temperature coefficient of resonance frequency generally excessive or quality factor it is relatively low and can not application request.At present to micro- Most of research of ripple media ceramic is the summary of experience drawn by many experiments, but illustrates micro- without complete theory The relation of structure and dielectric properties is seen, therefore, its resonance frequency can not be also predicted from the composition and structure of compound in theory The microwave dielectric property such as rate temperature coefficient and quality factor, which greatly limits low temperature co-firing technology and microwave multilayer The development of device.Exploration and exploitation can low-temperature sintering there is (- 10ppm/ DEG C≤τ of near-zero resonance frequency temperature coefficient simultaneouslyf≤ + 10ppm/ DEG C) with the microwave dielectric ceramic of higher figure of merit it is that those skilled in the art thirst for solving but being all the time difficult to always The problem succeeded.
The content of the invention
It is an object of the invention to provide a kind of there is good heat endurance to be situated between with low-loss ultralow dielectric microwave Electroceramics material and preparation method thereof.
The chemical composition of the microwave dielectric ceramic material of the present invention is Li3W2Ga3O12。
The preparation method step of this microwave dielectric ceramic material is：
(1) it is Li more than 99.9% (percentage by weight) by purity2CO3、WO3And Ga2O3Starting powder press Li3W2Ga3O12Composition weigh dispensing.
(2) step (1) raw material wet ball-milling is mixed 12 hours, ball-milling medium is distilled water, it is big at 1100 DEG C after drying Pre-burning 6 hours in gas atmosphere.
(3) after binding agent is added in powder made from step (2) and is granulated, re-compacted shaping, finally 1150~ Sintered 4 hours in 1200 DEG C of air atmospheres；Described binding agent uses mass concentration for 5% poly-vinyl alcohol solution, polyethylene Alcohol addition accounts for the 3% of powder gross mass.
Advantages of the present invention：Li3W2Ga3O12Ceramic sintering temperature is relatively low, and cost of material is low；Its quality factor q f values are up to 81000-102000GHz, dielectric constant reaches 9.6~10.3, the temperature coefficient τ of its resonant frequencyfSmall, temperature stability is good； The manufacture of the microwave devices such as various medium substrates, resonator and wave filter is can be widely used for, low temperature co-firing technology can be met and micro- The technology of ripple multilayer device needs.
Embodiment
Embodiment：
Table 1 shows 3 specific embodiments and its microwave dielectric property for constituting the different sintering temperatures of the present invention.It is made Preparation Method is as described above, carry out the evaluation of microwave dielectric property with cylindrical dielectric resonator method.
This ceramics can be widely used for the manufacture of the microwave devices such as various medium substrates, resonator and wave filter, can meet shifting The technology of the systems such as dynamic communication and satellite communication needs.
Table 1：

Claims (1)

1. a kind of high quality factor temperature-stable ultralow dielectric microwave dielectric ceramic, it is characterised in that the micro-wave dielectric Ceramics chemical composition be：Li3W2Ga3O12；
The preparation method of the microwave dielectric ceramic is concretely comprised the following steps：
(1) it is Li more than 99.9% (percentage by weight) by purity2CO3、WO3And Ga2O3Starting powder press Li3W2Ga3O12's Composition weighs dispensing；
(2) step (1) raw material wet ball-milling is mixed 12 hours, ball-milling medium is distilled water, in 1100 DEG C of air gas after drying Pre-burning 6 hours in atmosphere；
(3) after binding agent is added in powder made from step (2) and is granulated, re-compacted shaping, finally at 1150~1200 DEG C Sintered 4 hours in air atmosphere；Described binding agent uses mass concentration for 5% poly-vinyl alcohol solution, polyvinyl alcohol addition Amount accounts for the 3% of powder gross mass.
CN201710268595.2A 2017-04-23 2017-04-23 A kind of gallate ultralow dielectric microwave dielectric ceramic Withdrawn CN107010952A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113651599A (en) * 2021-08-19 2021-11-16 桂林理工大学 Gallate microwave dielectric ceramic with low dielectric constant and high quality factor and preparation method thereof
CN113651600A (en) * 2021-08-19 2021-11-16 桂林理工大学 Germanate microwave dielectric ceramic with low dielectric constant and high quality factor and preparation method thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113651599A (en) * 2021-08-19 2021-11-16 桂林理工大学 Gallate microwave dielectric ceramic with low dielectric constant and high quality factor and preparation method thereof
CN113651600A (en) * 2021-08-19 2021-11-16 桂林理工大学 Germanate microwave dielectric ceramic with low dielectric constant and high quality factor and preparation method thereof

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