JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 23
·20247-20252
·
IF 2.324
Zhang Yun,Ding Shihua,Song Tianxiu,Huang Long,Zhang Xiaoyun
Rutile-structured CoTiNb 2 O 8 ceramics were synthesized via traditional solid-state route. The effects of LiF addition on their sintering behavior, phase composition, microstructure and microwave dielectric properties were investigated systematically in this study. The sintering temperature was successfully lowered to 950 °C by a small amount (1 wt%) of sintering aid. XRD and EDS results indicated that chemical reaction between LiF and host ceramic took place during sintering process. And CoTiNb 2 O 8 with Li 0.8 Co 0.2 Nb 0.96 O 3 second phase coexisted in the entire composition range. The addition of LiF to the CoTiNb 2 O 8 ceramics induced a limited degradation in microwave dielectric properties. The ε r and Q × f values of the low-fired CoTiNb 2 O 8 ceramics ranged from 39.4 to 53.9 and 17,580 GHz to 20,147 GHz, respectively. While the τ f decreased in negative values with increasing LiF content. When sintered at 950 °C, the CoTiNb 2 O 8 ceramic doped with 1 wt% LiF had excellent microwave dielectric properties: ε r = 53.9, Q × f = 20,147 GHz, and τ f = 77.2 ppm/°C, making them promising for LTCC applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2022
·
IF 6.364
Xianqiang Chen,Binfeng Zhao,Naichao Chen,Jin Cheng,Mingzhao Dang,Feng Wang,Xinwei Xu,Hong Wang
Low-temperature-fired microwave ceramics are key to realizing the integration and miniaturization of microwave devices. In this study, a facile wet chemical method was applied to synthesize homogenous nano-sized CaF 2 powders for simultaneously achieving low-temperature sintering and superior microwave dielectric properties . Pure CaF 2 ceramics sintered at 950 °C for 6 h with good microwave dielectric properties (ε r = 6.22, Q×f = 36,655 GHz, and τ f = −102 ppm/°C) was achieved. The microwave dielectric properties of the CaF 2 ceramics were further improved by introducing LiF as a sintering aid. The sintering temperature of CaF 2 -based ceramics was effectively lowered from 950 °C to 750 °C with 10 wt% LiF doping, and excellent microwave dielectric properties (ε r = 6.37, Q×f = 65,455 GHz, and τ f = −71 ppm/°C) were obtained.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xinwen Liu,Bingchu Mei,Guolong Tan
Transparent hexagonal 2 at.% Yb:Sr 5 (PO 4 ) 3 F ( S -FAP) ceramics were effectively fabricated by hot pressing the coprecipitated powder employing LiF as the sintering additive. The effects of LiF doping levels (0–0.5 wt%) and sintering temperature (820–940 °C) on microstructural development and optical characteristics of samples were examined. The results showed that the addition of LiF and the evaluated sintering temperature accelerated the grain development and densification process of Yb:S-FAP ceramics. Also, the full densification process of low-doped LiF ceramic samples was found to be strongly dependent on the reduced sintering temperature. For the Yb:S-FAP transparent ceramic sintered at the lowest temperature of 850 °C than previously reported with 0.1 wt% LiF, which have an optical in-line transmittance of 59.7% and 79.66% at 500 and 1100 nm respectively. The corresponding scattering sources of ceramic samples were analyzed by the surface SEM of different magnification at different LiF doping concentrations, and residual LiF, residual porosity, and grain boundary scattering were considered to be the main scattering sources. The spectral results showed that the LiF-doped Yb:S-FAP transparent ceramics had a wide absorption peak at 975 nm with the full width at half maximum (FWHM) of 15 nm and possessed a fluorescence lifetime of 1.12 ms.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
·
2019
·Vol. 49
·期 1
·773-779
·
IF 1.676
Zheng Jinjie,Xu Huizhong,Yang Yaokang,Liu Lintao,Wu Haitao
Low-firing 1–4 wt.% LiF-doped Li 2 Mg 3 Ti 0.95 (Mg 1/3 Ta 2/3 ) 0.05 O 6 (LMTT) ceramics were synthesized via solid state reaction method. The effects of LiF on the phase composition, sintering behavior as well as microwave dielectric properties were systematically discussed. Adding LiF additives could lower the sintering temperature to 950°C for LMTT ceramics. X-ray powder diffraction analysis indicated that all the compounds prepared in this work have cubic symmetry with space group Fm - 3m . Typically, LMTT with 2 wt.% LiF exhibited a dense uniform microstructure and optimized microwave dielectric properties of ε r ∼ 15.1 (± 0.2), Q · f ∼ 60,100 GHz (at 8.3 GHz), and τ f ∼ − 20.45 ppm/°C at 950°C. In addition, the good chemical compatibility with Ag electrode made LMTT-2 wt.% LiF ceramic an appropriate candidate for low temperature co-fired ceramic.
研究领域:
材料科学
·
电子材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Pengfei Wei,Cen Qian,Luchao Ren
This study demonstrates the successful synthesis of (1- x )MgGa 2 O 4 - x LiF ( x = 0.1–0.4, mass fraction) ceramics via solid-state reaction, achieving a significant reduction in sintering temperature from 1410 to 850 °C. The XRD and Raman testing results showed the formation of a new phase of LiGaO 2 , which affected the dielectric properties. Variations in the sintering density and ionic polarizability cause changes in the permittivity. In addition, the packing fraction analysis of MgGa 2 O 4 , which influences the crystal structure stability, elucidates the intrinsic mechanisms affecting the dielectric loss. The composite effect makes the τ f value of the ceramic shift toward the negative value, owing to the large negative frequency temperature coefficient of LiF. Finally, (1- x )MgGa 2 O 4 - x LiF ( x = 0.3) sintered at 850 °C possesses the superior dielectric properties: ε r = 9.45, Q × f = 32,790 GHz, τ f = −28.5 ppm/°C (at 14 GHz). In addition, (1- x )MgGa 2 O 4 - x LiF ( x = 0.3) ceramics exhibit good cofiring compatibility with Ag electrodes promoting the ceramic to be a suitable candidate for LTCC applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2025
·
IF 3.2
Chenxi Cai,Jiamao Li,Junxian Wang,Yuxuan Ren,Yunfeng Guo
Development of low-temperature co-fired ceramics (LTCC) is a worldwide focus due to high integration, energy saving, and environmental friendliness. Herein, a beneficial attempt was made to decrease the sintering temperature of the Li2Mg6TiO9 (L2M6T) ceramic via doping LiF for LTCC applications. Furthermore, the phase structure, microstructure, and microwave dielectric properties of the doped ceramics were investigated in detail. The densification temperature of L2M6T was significantly reduced from 1450 to 1025 °C after LiF doping, which was conducive to energy saving. A small amount of LiF doping resulted in the formation of a MgO-type solid solution. The increase in molecular polarizability led to an increase in the dielectric constant (εr). An appropriate amount of LiF doping reduced the lattice vibration damping behavior, which in reverse improved the quality factor (Q × f). The substitution of F– ion for the O2– ion increased the bond energy of the total chemical bond, optimizing the temperature coefficient of resonant frequency (τf). The L2M6T ceramic-doped 3 wt % LiF presented the best microwave dielectric properties of εr = 12.37, Q × f = 112,400 GHz, and τf = −29.5 ppm/°C. In addition, the ceramic sintered at 950 °C exhibited great chemical compatibility with silver electrodes, indicating that it is potentially valuable for LTCC applications.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2017
·Vol. 28
·期 18
·13278-13282
·
IF 2.019
Mao Y. X.,Pan H. L.,Zhang Y. W.,Liu Q. Q.,Wu H. T.
Li 2 Mg 3 SnO 6 (abbreviation for LMS) ceramics doped with 1–4 wt% lithium fluoride (LiF) were prepared by the conventional solid-state reaction method. The effects of LiF addition on the phase compositions, sintering behaviors and microwave dielectric properties of LMS ceramics were investigated. A small amount of LiF addition could effectively decrease the sintering temperatures due to the liquid phase in the sintering process and induced no apparent degradation of the microwave dielectric properties. The optimized quality factor values for each composition firstly increased and then decreased with the increase of the LiF content. Whereas, the optimized dielectric permittivity increased with increasing of the LiF content. Distinguished microwave dielectric properties with a dielectric constant ( ε
r ) of 11.13, a quality factor ( Q · f ) of 104,750 GHz, and a temperature coefficient of resonant frequency (τ
f
) of −10.83 ppm/°C were obtained for LMS ceramics sintered at 950 °C doped with 3 wt% LiF, which showed that the materials were suitable for the low temperature co-fired ceramics applications (LTCC).
研究领域:
材料科学
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Bingjing Tao,Weifeng Wang,Huanyu Liu,Tianxiu Du,Haitao Wu,Chunfang Xing,Dongzhi Wang,Yuping Zhang
Li 4 Mg 3 [Ti 0 · 6 (Mg 1/3 Nb 2/3 ) 0.4 ] 2 O 9 (LMT 0.6 (MN) 0.4 O) ceramics doped with 1–5 wt% lithium fluoride (LiF) were prepared through a conventional solid-state reaction at a relatively low sintering temperature . The influences of the LiF additive on the micromorphology, crystal phase composition, and sintering behavior, as well as the microwave dielectric properties of the LMT 0.6 (MN) 0.4 O ceramics were explored in depth. The addition of the LiF sintering additive reduced the densification temperature of the LMT 0.6 (MN) 0.4 O ceramics from 1450 °C–950 °C. X-ray powder diffractometer patterns indicated that a single phase formed for all experimental samples. Scanning electron microscopy photographs revealed that dense and homogeneous microstructures were obtained at 950 °C for the LMT 0.6 (MN) 0.4 O ceramics with 3–5 wt% LiF. Additionally, the optimized microwave dielectric properties, including ε r = 16.24, Q·f = 107,828 GHz (at 8.13 GHz), and τ f = −6.25 ppm/°C were achieved in the prepared LMT 0.6 (MN) 0.4 O ceramics with 4 wt% LiF at the sintering temperature of 950 °C. Furthermore, the excellent chemical compatibility between this component and silver were confirmed based on the results of XRD and EDS analyses, suggesting that the LMT 0.6 (MN) 0.4 O ceramics with 4 wt% LiF could be a suitable material for the application of low temperature co-fired ceramics.
研究领域:
材料科学
·
陶瓷
·
微波工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）