KR100415219B1 - Ceramic Compositions of Microwave Dielectrics - Google Patents
Ceramic Compositions of Microwave Dielectrics Download PDFInfo
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Abstract
본 발명은 하기 화학식 1의 조성을 갖는 마이크로파용 유전체 세라믹 조성물에 관한 것이다.The present invention relates to a dielectric ceramic composition for microwave having a composition of the formula (1).
<화학식 1><Formula 1>
(1-x)(Al1/2Ta1/2)O2-xTiO2 (1-x) (Al 1/2 Ta 1/2 ) O 2 -xTiO 2
상기 식에서, x는 0.1≤x≤0.5를 충족시키는 값이다.Wherein x is a value that satisfies 0.1 ≦ x ≦ 0.5.
본 발명에 따른 상기 조성물을 사용하면 공진기, 대역 통과 필터, 듀플렉서 및 안테나 등으로서의 성능이 우수한 이동 통신용 부품을 제조하는 것이 가능하다.By using the composition according to the present invention, it is possible to manufacture components for mobile communication which are excellent in performance as resonators, band pass filters, duplexers, antennas, and the like.
Description
본 발명은 높은 품질계수와 유전율을 가지며 또한 공진 주파수의 온도 계수가 안정한 마이크로파용 유전체 세라믹 조성물에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric ceramic composition for microwaves having a high quality factor and dielectric constant and having a stable temperature coefficient of resonance frequency.
최근 AMPS(Advanced Mobile Phone Service), PCS(Personal Communication System) 등의 무선 전화기, GPS(Global Positioning System) 안테나 등의 이동 통신, 위성 방송, 위성 통신 등에 주파수 대역이 300 MHz 내지 300 GHz인 마이크로파를 이용한 통신 시스템이 급속히 발전하고 있으며, 이러한 뉴 미디어의 실용화를 위해 공진기, 안테나, 대역 통과 (또는 저지) 필터, 듀플렉서 및 마이크로파 집적회로(MIC) 등에 고주파용 유전체 세라믹의 응용이 크게 증대되고 있다. 유전체 내에서 마이크로파의 파장은 유전율(εr)의 1/2 제곱과 주파수에 반비례하므로 부품의 소형화를 위해서는 유전율과 사용 주파수가 커야 한다. 일반적으로 유전율과 품질계수 (Q) 값은 반비례 관계에 있으며 1 내지 2 GHz 이상의 고주파에서는 큰 품질계수 (상대적으로 유전율은 작아짐)를 갖는 유전체 소재가 요구되나 앞에서 언급되었듯이 사용 주파수가 커짐에 따라 부품의 크기가 충분히 작아져 현재 800 MHz 대역의 셀룰러용 필터류에는 유전율 90 대역, 1.9 GHz 대역의 PCS용 필터류에는 유전율 38 전후의 유전체 소재가 이용되며, 향후 WLL(Wireless Local Loop) 및 IMT(International Mobile Telecommunication) 2000 등으로 주파수가 더욱 고주파화됨에 따라 유전율 20 대역의 소재가 이용될 것이며 현재 각종 공진기에 활발히 이용되어지고 있다.Recently, microwaves with a frequency band of 300 MHz to 300 GHz are used for mobile communication, satellite broadcasting, and satellite communication, such as AMPS (Advanced Mobile Phone Service), PCS (Personal Communication System), and mobile phones such as Global Positioning System (GPS) antennas. Communication systems are rapidly developing, and the application of high frequency dielectric ceramics to resonators, antennas, band pass (or stop) filters, duplexers, and microwave integrated circuits (MICs) has been greatly increased for the practical use of such new media. In a dielectric, the wavelength of the microwave is inversely proportional to half the square of the permittivity (ε r ) and the frequency, so the dielectric constant and frequency of use must be large for the miniaturization of components. In general, dielectric constant and quality factor (Q) values are inversely related, and at high frequencies above 1 to 2 GHz, dielectric materials with large quality factors (relatively smaller permittivity) are required, but as mentioned above, Since the size of the filter is small enough, dielectric filters with dielectric constants before and after the dielectric constant of 38 are used for cellular filters in the 800 MHz band and 90 s for PCS, and for PCS filters in the 1.9 GHz band. As the frequency becomes higher, such as 2000, materials with a dielectric constant of 20 bands will be used and are being actively used in various resonators.
지금까지 개발된 유전율 20 대역의 대표적인 유전체로는, MgTiO3-CaTiO3계를 들 수 있는데, 이러한 유형의 유전체는 품질계수 Q값이 8000 (at 7 GHz)이며 유전율 εr이 21이고 공진 주파수의 온도 계수 TCF가 0 ppm/℃이다[문헌 (K. Wakino, Ferroelectrics, 91, 69(1989)) 참조]. 이 정도의 Q·f0값 (56000 GHz)은 부품으로의 적용에 문제는 없으나 주파수의 선택도를 향상시키기 위해서는 일반적으로 더욱 큰 Q값이 선호된다.Representative dielectric materials of the 20 bands developed so far include the MgTiO 3 -CaTiO 3 system, which has a quality factor Q of 8000 (at 7 GHz) with a dielectric constant of ε r of 21 and a resonance frequency of The temperature coefficient TCF is 0 ppm / ° C. (see K. Wakino, Ferroelectrics, 91, 69 (1989)). The degree of Q · f 0 value (56000 GHz) is a problem with the application of the parts of, but is generally greater the Q value in order to improve the selectivity of the frequency is to be preferred.
본 발명의 목적은 유전율이 20 대역이며 공진 주파수의 온도 계수가 안정하고 유전 손실이 작은 (품질계수가 큼) 마이크로파용 유전체 세라믹 조성물을 제공하는 것이다.An object of the present invention is to provide a dielectric ceramic composition for microwaves having a dielectric constant of 20 bands, stable temperature coefficient of resonance frequency, and low dielectric loss (large quality factor).
본 발명의 다른 목적은 공진 주파수의 온도 계수를 조성의 변화에 따라 용이하게 조절할 수 있는 마이크로파용 유전체 세라믹 조성물을 제공하는 것이다.Another object of the present invention is to provide a dielectric ceramic composition for microwave which can easily adjust the temperature coefficient of the resonance frequency according to the change of composition.
위와 같은 본 발명의 목적은 하기 화학식 1의 조성을 갖는 유전체 세라믹 조성물을 제공함으로써 달성된다.The object of the present invention as described above is achieved by providing a dielectric ceramic composition having a composition of the following formula (1).
상기 식에서, x는 0.1≤x≤0.5를 충족시키는 값이다.Wherein x is a value that satisfies 0.1 ≦ x ≦ 0.5.
본 발명에 따른 유전체 조성물은 유전율이 14.1 내지 45.5이고, Q·f0값(GHz)이 6700 내지 76890이며, 공진 주파수의 온도 계수 (TCF)의 범위가 -31.7 내지 +99.9 ppm/℃이며, 조성의 변화에 따라 TCF를 0 ppm/℃로 조절이 가능하여 고주파용 유전체 세라믹의 부품으로 사용되는 재료로서 이용될 수 있다.A dielectric composition of the present invention is the dielectric constant is 14.1 to 45.5, Q 0 · f value (GHz) is 6700 to 76 890, and the range of the resonance frequency temperature coefficient (TCF) of -31.7 to +99.9 ppm / ℃, Composition According to the change of the TCF can be adjusted to 0 ppm / ℃ can be used as a material used as a component of the high-frequency dielectric ceramic.
본 발명의 유전체 세라믹 조성물은 음(-)의 공진 주파수의 온도 계수를 갖는 (Al1/2Ta1/2)O2와 양(+)의 공진 주파수의 온도 계수를 갖는 TiO2를 일정 비율로 혼합한 조성물로서, 그 특성은 (Al1/2Ta1/2)O2와 TiO2의 조성비와 소결온도에 따라서 변화된다. (Al1/2Ta1/2)O2는 유전율이 8.7, Q·f0값(GHz)이 60830, 공진 주파수의 온도 계수가 -55.2 ppm/℃이며, TiO2는 유전율이 104, Q·f0값(GHz)이 42000, 공진 주파수의 온도 계수가 +450 ppm/℃이다. 따라서, 상대적으로 높은 유전율과 양(+)의 공진 주파수의 온도 계수를 갖는 TiO2의 함량이 증가함에 따라, (Al1/2Ta1/2)O2와TiO2로 이루어진 유전체의 유전율은 점진적으로 증가하고, Q·f0값(GHz)은 증가 후 감소하며, 공진 주파수의 온도 계수는 음의 값에서 양의 값으로 증가하여, 유전체의조성의 변화에 따라 공진 주파수의 온도 계수를 조절할 수 있다.The dielectric ceramic composition of the present invention has a ratio of (Al 1/2 Ta 1/2 ) O 2 having a temperature coefficient of negative resonant frequency and TiO 2 having a temperature coefficient of positive resonant frequency. As a mixed composition, the properties thereof change depending on the composition ratio of (Al 1/2 Ta 1/2 ) O 2 and TiO 2 and the sintering temperature. (Al 1/2 Ta 1/2) O 2 is a dielectric constant of 8.7, Q 0 · f value (GHz) is the temperature coefficient of 60 830, the resonant frequency and -55.2 ppm / ℃, TiO 2 is a dielectric constant of 104, Q · the value f 0 (GHz) 42000, is the temperature coefficient of resonant frequency +450 ppm / ℃. Therefore, as the content of TiO 2 with relatively high dielectric constant and temperature coefficient of positive resonant frequency increases, the dielectric constant of the dielectric composed of (Al 1/2 Ta 1/2 ) O 2 and TiO 2 gradually increases. increased and, Q · f 0 value (GHz) is decreases then increases, the temperature coefficient of the resonance frequency is increased from a negative value to a positive value, the number depending on the change in the dielectric composition to control the temperature coefficient of the resonant frequency have.
본 발명에 따른 유전체 세라믹 조성물은 출발 물질로서 예를 들어 Al2O3, Ta2O5및 TiO2를 사용하여 일반적으로 알려진 세라믹 제조 방법으로 제조할 수 있다. 구체적으로 설명하면, Al2O3, Ta2O5및 TiO2를 사용 전에 잘 건조시킨 후 이들 시료를 일정 조성비로 혼합한 분말을 1100 내지 1300℃의 온도에서 2 내지 4 시간 동안 하소하고 분쇄한 후, 성형 첨가제로 5% PVA 수용액을 10 중량% 첨가하여 직경 10 mm, 두께 5 내지 6 mm의 원기둥형 시편을 가압 성형하며 유기 결합제를 제거하기 위해 600℃의 온도에서 1 시간 동안 열처리한 후 대기 중에서 1300 내지 1600℃의 온도에서 1 내지 5 시간 동안 소결하여 제조할 수 있다.The dielectric ceramic composition according to the present invention can be prepared by a generally known ceramic manufacturing method using, for example, Al 2 O 3 , Ta 2 O 5 and TiO 2 as starting materials. Specifically, after Al 2 O 3 , Ta 2 O 5 and TiO 2 are dried well before use, powders mixed with these samples at a constant composition ratio are calcined and ground at a temperature of 1100 to 1300 ° C. for 2 to 4 hours. Thereafter, 10% by weight of a 5% PVA aqueous solution was added as a molding additive to form a cylindrical specimen having a diameter of 10 mm and a thickness of 5 to 6 mm, and heat-treated at a temperature of 600 ° C. for 1 hour to remove the organic binder. It can be prepared by sintering for 1 to 5 hours at a temperature of 1300 to 1600 ℃.
소결 시편의 유전율, Q값 및 공진 주파수의 온도 계수 등의 유전 특성은 공지된 유전체 공진기 법으로 측정할 수 있다.Dielectric properties such as dielectric constant, Q value, and temperature coefficient of resonance frequency of the sintered test piece can be measured by a known dielectric resonator method.
이하, 본 발명을 보다 구체적으로 실시예를 들어서 상세히 설명하나, 본 발명의 범위가 하기 실시예에 의해 한정되는 것은 아니다.Hereinafter, the present invention will be described in more detail with reference to Examples, but the scope of the present invention is not limited by the following Examples.
<실시예><Example>
순도 98%의 Al2O3와 99%의 Ta2O5및 99.9%의 TiO2를 사용 전에 잘 건조시킨 후 이들 시료를 하기 표 1에 기재되어 있는 조성비로 혼합하고, 혼합 분말을 대기 중에서 1200℃의 온도에서 4 시간 정도 하소하여 분쇄한 후 성형 첨가제로 5% PVA 수용액을 10 중량% 첨가하여 직경 10 mm, 두께 5 내지 6 mm의 원기둥형 시편으로 가압 성형하였다. 성형된 시편은 유기 결합제를 제거하기 위해 600℃의 온도에서 1시간 동안 열처리한 후 대기 중에서 1350 내지 1500℃의 온도에서 3 시간 동안 소결하였다.Al 2 O 3 with a purity of 98% and Ta 2 O 5 with 99% and 99.9% of TiO 2 were dried well before use, and these samples were mixed at the composition ratios shown in Table 1 below, and the mixed powder was mixed in the air at 1200 After calcination by calcination at a temperature of about 4 hours and pulverized, 10% by weight of a 5% PVA aqueous solution was added as a molding additive and pressure molded into a cylindrical specimen having a diameter of 10 mm and a thickness of 5 to 6 mm. The molded specimens were heat treated at a temperature of 600 ° C. for 1 hour to remove the organic binder and then sintered for 3 hours at a temperature of 1350 to 1500 ° C. in air.
소결 시편의 양면을 연마지 (SiC paper)로 잘 연마한 후, 도파관 속에 넣고 공지된 유전체 공진기 법으로 유전율, Q값 및 공진 주파수의 온도 계수를 측정하였다. 이때, 측정 주파수는 6 내지 12 GHz이고, 측정 온도 범위는 -15 내지 85℃이었다. 각 시편의 마이크로파 유전 특성을 표 1에 나타낸다.Both surfaces of the sintered specimens were polished well with a SiC paper, and then placed in a waveguide to measure temperature coefficients of dielectric constant, Q value and resonant frequency by a known dielectric resonator method. At this time, the measurement frequency was 6 to 12 GHz, and the measurement temperature range was -15 to 85 ° C. The microwave dielectric properties of each specimen are shown in Table 1.
상기 표 1로부터, TiO2의 함량이 증가함에 따라, 유전율이 점진적으로 증가하였고, Q·f0값(GHz)이 대체적으로 증가하다가 감소하였으며, 공진 주파수의 온도 계수가 음의 값에서 양의 값으로 증가하였다는 것을 알 수 있다. 특히, TiO2의 함량이 0.2 몰인 화학식 1의 유전체를 1450℃에서 3 시간 소결시 유전율이 29.4이고, Q·f0값이 75470 GHz이며, 공진 주파수의 온도 계수가 0 ppm/℃인 우수한 마이크로파용 유전체를 제조할 수 있었다.From Table 1, as the content of TiO 2 increases, the dielectric constant gradually increases, the Q f 0 value (GHz) increases and decreases substantially, and the temperature coefficient of the resonant frequency is a positive value from a negative value. It can be seen that increased. Particularly, when sintering a dielectric material of Formula 1 having a content of 0.2 mol of TiO 2 at 1450 ° C. for 3 hours, the dielectric constant was 29.4, the Q f 0 value was 75470 GHz, and the temperature coefficient of resonance frequency was 0 ppm / ° C. Dielectrics could be produced.
본 발명의 신규한 조성물은 현재까지 개발된 유전율 20 대역의 대표적인 마이크로파 유전체인 MgTiO3-CaTiO3보다 품질계수의 값이 우수하여 주파수의 선택도를 향상시킬 수 있으며, 따라서 이러한 본 발명에 따른 조성물을 사용하면 공진기, 대역 통과 필터, 듀플렉서 및 안테나 등으로서의 성능이 우수한 이동 통신용 부품을 제조하는 것이 가능하다.The novel composition of the present invention has better quality coefficient values than MgTiO 3 -CaTiO 3, which is a typical microwave dielectric with a dielectric constant of 20 bands, thus improving the selectivity of frequencies. When used, it is possible to manufacture components for mobile communication which are excellent in performance as resonators, band pass filters, duplexers, antennas, and the like.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2001-0014667A KR100415219B1 (en) | 2001-03-21 | 2001-03-21 | Ceramic Compositions of Microwave Dielectrics |
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|---|---|---|---|
| KR10-2001-0014667A KR100415219B1 (en) | 2001-03-21 | 2001-03-21 | Ceramic Compositions of Microwave Dielectrics |
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| KR20020074714A KR20020074714A (en) | 2002-10-04 |
| KR100415219B1 true KR100415219B1 (en) | 2004-01-16 |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6376206A (en) * | 1986-09-18 | 1988-04-06 | 日本特殊陶業株式会社 | Alumina ceramic composition |
| JPH029748A (en) * | 1988-06-27 | 1990-01-12 | Canon Inc | Ceramics and circuit substrate formed by using the same ceramics and electronic circuit substrate as well as production of ceramics |
| JPH0632617A (en) * | 1992-07-13 | 1994-02-08 | Tosoh Corp | Sintered double oxide |
| JPH08236390A (en) * | 1995-02-28 | 1996-09-13 | Kyocera Corp | Capacitor material, multilayered alumina wiring board, and semiconductor device containing package |
| JPH0952760A (en) * | 1995-08-11 | 1997-02-25 | Kyocera Corp | Dielectric ceramic composition |
| KR19980014361A (en) * | 1996-08-10 | 1998-05-25 | 박원훈 | Dielectric ceramic composition for high frequency use |
| KR20010100258A (en) * | 2000-03-31 | 2001-11-14 | 박호군 | Dielectric Ceramic Compositions for High Frequency |
-
2001
- 2001-03-21 KR KR10-2001-0014667A patent/KR100415219B1/en not_active IP Right Cessation
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6376206A (en) * | 1986-09-18 | 1988-04-06 | 日本特殊陶業株式会社 | Alumina ceramic composition |
| JPH029748A (en) * | 1988-06-27 | 1990-01-12 | Canon Inc | Ceramics and circuit substrate formed by using the same ceramics and electronic circuit substrate as well as production of ceramics |
| JPH0632617A (en) * | 1992-07-13 | 1994-02-08 | Tosoh Corp | Sintered double oxide |
| JPH08236390A (en) * | 1995-02-28 | 1996-09-13 | Kyocera Corp | Capacitor material, multilayered alumina wiring board, and semiconductor device containing package |
| JPH0952760A (en) * | 1995-08-11 | 1997-02-25 | Kyocera Corp | Dielectric ceramic composition |
| KR19980014361A (en) * | 1996-08-10 | 1998-05-25 | 박원훈 | Dielectric ceramic composition for high frequency use |
| KR20010100258A (en) * | 2000-03-31 | 2001-11-14 | 박호군 | Dielectric Ceramic Compositions for High Frequency |
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| KR20020074714A (en) | 2002-10-04 |
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