Journal of Materials Chemistry C
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2021
·Vol. 9
·期 40
·14359-14370
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IF 7.393
Lingxia Li,Xubin Wang,Weijia Luo,Shun Wang,Tian Yang,Ji Zhou
Miniaturization, power dissipation and temperature stability are the most critical factors restricting the microwave use of ceramic-based devices. Balancing them, especially for the ceramics with high dielectric constant, is a great challenge. Herein, a new strategy by trivalent ion (Al3+ and Ga3+) co-substitution is put forward in tungsten bronze structural Ba4Nd9.33Ti18O54 ceramics for millimeter-wave metamaterials, and a nearly 40% increase in Qf values with stable temperature characteristics is obtained. The crystal symmetry, morphology and the vibration modes are characterized by XRD, EDS and Raman spectroscopy, suggesting the varied internal strain and oxygen octahedron tilt from the mismatch of different cations. The best performance of Ba4Nd9.33Ti18−x(Al0.4Ga0.6)xO54−0.5x (BNT-AGx) is observed when x is 2.4: εr = 67.71, Qf = 13 675 GHz, τf = +4.4 ppm °C−1. Considering the dispersion relationship of BNT-AGx ceramics further, the structure of BNT-AGx metamaterials is uniquely designed, and the sub-wavelength BNT-AGx blocks are also fabricated to demonstrate the frequency selection filtering function with high temperature stability at the millimeter-wave band (>30 GHz), which is of great significance to achieve some eMBB (Enhanced Mobile Broadband) scenes of 5G (the 5th Generation) technology, from a metal loaded cavity to free space.
研究领域:
材料科学
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电子工程
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高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
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2021
·Vol. 104
·期 9
·4659-4668
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IF 3.784
Chao Du,Mao-Sen Fu,Di Zhou,Huan-Huan Guo,He-Tuo Chen,Jian Zhang,Jun-Ping Wang,Shao-Fei Wang,Hai-Wen Liu,Wen-Feng Liu,Long Li,Zhuo Xu
Microwave dielectric ceramics are considered to be one of the key materials for dielectric resonators (DR) and have very broad application prospects in the fifth generation (5G) mobile communication system. Here we have prepared high-quality factor Y 3 Al 5 O 12 (YAG) transparent dielectric ceramics using high-purity α-Al 2 O 3 and Y 2 O 3 powders by cold isostatic pressing of the vacuum sintered with tungsten meshes as the heating elements. Optimum relative permittivity ( ) ~10.53, quality factor Q × f (Q = 1/dielectric loss, f = resonant frequency) ~95, 270 GHz (at =7.37 GHz), and temperature coefficient of resonant frequency (TCF) ~ −51.7 ppm °C −1 were obtained at a sintering temperature of 1780°C for 12 h. For the first time, YAG transparent ceramic dielectric resonator antenna (DRA) is designed as a dominant mode and a higher-order mode using the aperture coupling feeding configuration excitation. The proposed transparent dielectric ceramic DRA can provide a broad impedance bandwidth of 4.193 GHz (ranging from 21.90 to 26.09 GHz) for S 11 < −10 dB, radiation efficiency of 92.1%, and compact DR unit. The proposed DRA can be used potentially as a 5G millimeter (mm)-wave multiple-input-multiple-output (MIMO) antenna unit.
研究领域:
材料科学
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通信工程
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电子工程
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2021
·Vol. 32
·期 13
·18205-18211
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IF 2.478
Jin Ding Hao,Hu Cheng Chao,Liu Bing
CaAl 2 − 2 x Zn x Ti x O 4 ( x = 0.05, 0.10, 0.15) ceramics with low permittivity have been prepared via a standard solid-state reaction method. The partial co-substitution of (Zn 0.5 Ti 0.5 ) 3+ for Al 3+ can effectively lower the sintering temperature of CaAl 2 O 4 ceramics by approximately 200 °C. Meanwhile, the large negative temperature coefficient of resonant frequency ( τ f = − 55 ppm/°C) of CaAl 2 O 4 ceramics can be simultaneously modified toward zero. With increasing x , the quality factor ( Q f ) indicates a downward changing trend owing to the appearance of ZnAl 2 O 4 and CaTiO 3 secondary phases. The optimum microwave dielectric properties ( ε r = 11.9, Q f = 28,090 GHz, and τ f = − 1.2 ppm/°C) are achieved at x = 0.15. Moreover, a microstrip patch antenna is fabricated using the x = 0.15 ceramic as the dielectric substrate. The fabricated antenna demonstrates a S 11 value of − 17.8 dB at 4.9 GHz and a measured − 10 dB bandwidth of 86 MHz. The good antenna performances suggest that the present ceramics are good candidates for 5G antenna applications at the sub-6 GHz band.
研究领域:
材料科学
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电子工程
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高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
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2022
·
IF 6.364
Shuai Li,Chen Li,Minmin Mao,Kaixin Song,Yaseen Iqbal,Amir Khesro,Sinan S. Faouri,Zhilun Lu,Bing Liu,Shikuan Sun,Dawei Wang
In this work, Zn-Ni co-modified LiMg 0.9 Zn 0.1- x Ni x PO 4 ( x = 0–0.1) microwave dielectric ceramics were fabricated using a solid state synthesis route. Rietveld refinement of the XRD data revealed that all ceramic samples have formed a single phase with olivine structure. SEM images showed that the samples have a dense microstructure, that agrees with the measured relative density of 97.73 %. Based on the complex chemical bond theory, Raman and infrared reflectance spectra, we postulate that ε r is mainly affected by the ionic polarizability, lattice and bond energy, while P-O bond plays a decisive role in Q×f and τ f value. Optimum properties of Q×f ~ 153,500 GHz, ε r ~ 7.13 and τ f ~ −59 ppm/°C were achieved for the composition LiMg 0.9 Zn 0.06 Ni 0.04 PO 4 sintered at 875 ℃ for 2 h. This set of properties makes these ceramics an excellent candidate for LTCC , wave-guide filters and antennas for 5 G/6 G communication applications.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2020
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IF 3.83
Atta Ullah,Hanxing Liu,Abdul Manan,Arbab Safeer Ahmad,Zhai Pengcheng,Hua Hao,Minghe Cao,Zhonghua Yao,Amjad Ullah,Abdullah Jan,Marwa Emmanuel,Javed Iqbal
The solid-state sintering route was employed for the production of (1-x)Bi 2 (Li 0 .5 Ta 1.5 )O 7 -xTiO 2 (x = 0, 0.02, 0.04, 0.06, 0.08) ceramics. The phase, microstructure and microwave dielectric properties of each ceramic composition were determined via X-ray diffraction, scanning electron microscopy and Haki Colmon resonator technique, respectively. The dielectric constant, tan δ and AC conductivity were also determined for the composition of x = 0.04. The TiO 2 addition developed new phases of Bi 3 Ti 4 O 12 and Bi 3 TaTiO 9 for x = 0.04 along with Bi 2 (Li 0 . 5 Ta 1.5 )O 7 phase which disappeared for x = 0.08. The τ f of Bi 2 (Li 0 . 5 Ta 1.5 )O 7 was tuned through zero by TiO 2 addition and good microwave dielectric properties ε r ~67.2, Q u f õ 13,767 GHz and τ f ~ −1.45 ppm/ ° C can be obtained for the composition of x = 0.04 sintered at 1050 °C for 2 h. This ceramic composition is a suitable candidate for 5G cellular base station resonator application.
研究领域:
材料科学
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电子工程
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高影响因子
Crystals
·
2023
·Vol. 13
·期 9
·1296
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IF 2.7
Yan Wang,Jiajing Li,Haipeng Zhu,Qilei Wang,Tulai Sun,Tao Ni,Yanghong Lin,Yu Liu,Minmin Mao,Ji Hu,Bing Liu,Hadi Barzegar Bafrooei,Zhongyan Ma,Yingjie Ren,Feng Shi,Ehsan Taheri-Nassaj,Dawei Wang,Kaixin Song
Mg2SiO4and MgSiO3ceramics with superior microwave dielectric properties are considered to be promising candidates for 5G applications. However, a slight deviation from the stoichiometric Mg/Si ratio will significantly influence their microwave dielectric properties, which will hinder their practical applications. In this work, thexMgO-SiO2(x= 1~2) ceramics were synthesized by a solid-state reaction method. The influence of the Mg/Si ratioxon the crystalline phase, microstructure, and microwave dielectric properties was investigated through X-ray diffraction (XRD), a scanning electron microscope (SEM), and the resonant cavity method. The XRD patterns revealed the coexistence of Mg2SiO4and MgSiO3within thexrange of 1~2, which was further demonstrated by the energy-dispersive X-ray spectra. The SEM images show a typical polycrystalline morphology of ceramics with an inhomogeneous grain size distribution. It is found that the microwave dielectric properties fluctuate at both sides of thexrange while those remain relatively stable with minor changes at the intermediate components, indicating an obvious low composition dependence helpful for practical applications. Further, a demonstrator of a microstrip patch antenna for 5G applications using the 1.5MgO-SiO2ceramic was designed and fabricated, and a return loss of −16.2 dB was demonstrated, which demonstrated the potential applications.Keywords:MgO-SiO2systems;5G application;microwave dielectric ceramics;phase composition
研究领域:
材料科学
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电子工程
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高影响因子
Crystals
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2022
·Vol. 12
·期 11
·1608
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IF 2.67
Zijun Ye,Yu Jiang,Minmin Mao,Zhiyu Xiu,Mengjiao Chi,Guofa Wu,Bing Liu,Dawei Wang,Bin Yang,Kaixin Song
In this work, Y2.95R0.05MgAl3SiO12(R = Yb, Y, Dy, Eu, Sm) microwave single-phase dielectric ceramics were successfully prepared via a conventional ceramic sintering technology by doping a series of rare earth elements (Yb, Y, Dy, Eu, Sm) with different ionic radii for the first time. The effects of A-sites occupied by rare earth elements on the microwave dielectric properties of Y2.95R0.05MgAl3SiO12were studied using crystal structure refinement, a scanning electron microscope (SEM), bond valence theory, P-V-L theory, and infrared reflection spectroscopy. It was found that the ionicity of the Y-O bond, the lattice energy, the bond energy, and the bond valance of the Al(Tet)-O bond had important effects on the microwave dielectric properties. Particularly, the optimum microwave dielectric properties,εr= 9.68,Q×f= 68,866 GHz, andτf= −35.8 ppm/°C, were obtained for Y2.95Dy0.05MgAl3SiO12when sintered at 1575 °C for 6 h, displaying its potential for 5G communication.Keywords:garnet;microwave dielectric properties;P–V–L theory;infrared reflection spectroscopy
研究领域:
材料科学
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通信工程
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高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 22
·37337-37347
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IF 5.6
Wei Wen,Ting Jiang,Jiaqi Wang,Feng Zhou,Yonghong Zhou
With the rapid development of 5G communication technology, there is an increasing demand for low-loss, thermally stable dielectric ceramics suitable for microwave filter applications. This study focuses on the effects of heavy rare-earth element doping (Dy 3+ , Ho 3+ , Er 3+ ) on the microwave dielectric properties of Zn 1.8 SiO 3.8 ceramics, aiming at potential applications in 5G communication filters. The doped ceramics, namely ZDSO, ZHSO, and ZESO, were synthesized and characterized by XRD , SEM, FTIR , Raman, and dielectric property measurements. The results show that the addition of rare-earth ions effectively reduces the sintering temperature to 1250 °C , promotes grain growth, and significantly improves the dielectric properties , with ZHSO being the best performer ( ε ᵣ = 7.02 , Q × f = 97,782 GHz , τ f = -28.03 ppm/°C ). Subsequently, microwave filters based on ZDSO, ZHSO, and ZESO were designed using Ansys HFSS simulation software, and their performance was evaluated through return loss (S 11 ), insertion loss (S 21 ). Simulation results indicate that the filters exhibit low S 21 and excellent S 11 in the frequency range of 6.425–7.125 GHz, along with superior frequency selectivity . Finally, the ZHSO-based filter was fabricated and measured using a vector network analyzer , confirming the reliability of the simulation results. These results highlight the promise of rare-earth-doped Zn 1.8 SiO 3.8 ceramics as cost-effective, environmentally friendly dielectric materials for high-performance microwave devices.
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高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yu Jiang,Huan Liu,Raz Muhammad,Xinjiang Luo,Kaixin Song,Minmin Mao,Shikuan Sun,Hadi Barzegar Bafrooei,Ehsan Taheri-Nassaj,Yaseen Iqbal,Rong Sun,Dawei Wang
Garnet-typed ceramics of Y 3 Mg 1- x Mn x Al 3 SiO 12 (0 ≤ x ≤ 0.2) have been synthesized using the traditional solid-state reaction method. The optimal microwave dielectric properties ( ε r = 10.73, Q׃ = 62,824 GHz, τ f = −34.8 ppm/°C) are obtained for Y 3 Mg 0.9 Mn 0.1 Al 3 SiO 12 ( x = 0.1) sintered at 1575 °C for 5h. A millimeter-wave dielectric resonator antenna is designed and fabricated using Y 3 Mg 0.9 Mn 0.1 Al 3 SiO 12 as a dielectric unit due to its excellent characteristics of low dielectric constant and high Q׃ . The designed DRA resonates at 24.94 GHz with a bandwidth ∼2.20 GHz (S 11 < −10 dB). The simulated gain and efficiency are 6.64 dBi and 91.08%, respectively. The results indicate that the Y 3 Mg 0.9 Mn 0.1 Al 3 SiO 12 ceramic has a potential application as an antenna for the 5G/6G millimeter wave frequency band.
研究领域:
材料科学
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通信工程
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电子工程
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高影响因子
Materials Today Advances
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2024
·
IF 8.1
Heming Li,Panpeng Wei,Yongqi Wang,Qiushi Zhu,Xinming Wang,Weiguo Gao,Lin Tao,Ke Ma,Zhizhi Hu,Wei Chen
Polyimide (PI) faces new challenges in meeting the requirements of low coefficient of thermal expansion (CTE), low dielectric content/loss, and high thermal stability to be utilized effectively as a substrate for flexible electronic materials. At present research, the CTE of PI films can be reduced to around 5 ppm/K, with Tg > 420 °C. However, it is difficult to balance low CTE and high Tg at the same time, and reducing dielectric performance is even more difficult. This study focused on synthesizing four types of PI films (using BPDA as the dianhydride) by employing biphenyl structure diamines (PDA, BZD, DPT, DMP) with an increasing number of benzene rings. The improvement in CTE, dielectric properties, and thermal stability was observed with an increase in the number of benzene rings and a decrease in the number of imine rings in the PI horizontal structure. The Tetraphenylene PI-DMP exhibited values of ε and tanθ as 3.31 and 4.73 ‰ respectively under 10 GHz . Additionally, the biphenyl PI films demonstrated commendable thermal stability (Tg = 442°C ), outstanding mechanical properties (elastic modulus > 10 GPa ), and a low CTE ( 2 ppm/K within the temperature range of 50–300 °C, and close to the 3.6 ppm/K CTE of monocrystalline silicon). The low CTE, high thermal stability, and low dielectric properties that 5G flexible substrate materials need to be qualified are simultaneously reflected in this study. MS theoretical calculations were used to analyze the results. The excellent consistency with experimental results can promote the feasibility of MS theory in PI dielectric properties at high-frequency (10 Ghz). This innovative approach is anticipated to provide foldable chip fields with intrinsic biphenyl PI materials possessing low dielectric, low CTE, and high thermal stability.
研究领域:
材料科学
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电子工程
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高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Siyu Xiong,Xiaowei Zhu,Guobin Zhu,Deqin Chen,Hongbo Cui,Laijun Liu,Chunchun Li
A microwave dielectric ceramic based on lithium aluminum silicate (LiAlSi2O6) with ultralow permittivity was synthesized using the traditional solid-state reaction technique, and its dielectric characteristics at microwave frequencies are presented. The nominal LiAlSi2O6 ceramic exhibited a relative permittivity of 3.95. To enhance the material properties, LiAlSi2O6-x wt % B2O3 microwave dielectric ceramics were fabricated by incorporating a low-melting-point sintering aid (B2O3), achieving a relative density exceeding 94%. The resultant ceramics exhibited a relative permittivity (εr) ranging from 3.95 to 4.42, a microwave quality factor (Q × f) between 24,720 and 28,990 GHz, and a resonant frequency temperature coefficient (τf) varying from −45.9 to −20.6 ppm/°C. Additionally, the introduction of B2O3 broadened the sintering temperature window and effectively lowered the optimal sintering temperature from 1400 to 1200 °C. Furthermore, LiAlSi2O6 ceramics demonstrated a near-zero coefficient of thermal expansion (CTE) of 1.44 ppm/°C, which is advantageous for applications requiring high thermal stability. Based on LiAlSi2O6-2.0 wt % B2O3 ceramics with εr = 4.42, Q × f = 28,990 GHz, and τf = −20.6 ppm/°C, a microstrip patch antenna was designed and fabricated. Testing of the antenna revealed exceptional performance, including a center frequency of 4.98 GHz, a bandwidth of 280 MHz (−10 dB), and a total efficiency reaching up to 93.7%. These findings underscore the promising potential of this material in advanced microwave and wireless communication applications.
研究领域:
材料科学
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无线通信
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Meng Fei Zhou,Cheng Chao Hu,Jian Bing Yin,Yu Jiang,Bing Liu,Kai Xin Song
SrF 2 is a promising low- ε r fluoride with outstanding microwave dielectric properties , while densification of SrF 2 ceramics is challenging via traditional thermal sintering (TTS). In this work, dense SrF 2 ceramics with 93.4%–97.2% relative density have been obtained via cold sintering (300 MPa–900 MPa, 150 °C, 1 h) and subsequent post-annealing at 950 °C/3 h. The pretreated cold sintering process is beneficial for microstructure optimization, where the maximum Qf value (62,037 GHz) is obtained at 750 MPa, nearly three times higher than the TTS sample (21,080 GHz). An ultra-low dielectric constant ( ε r ) of 5.94 is simultaneously obtained, together with a temperature coefficient of resonant frequency τ f = −78.26 ppm/°C. Good chemical compatibility between SrF 2 ceramics and silver is verified, indicating great promise for their use in LTCC technology. Moreover, the low- ε r and high Qf values of the cold sintering optimized SrF 2 ceramics suggest great potential in the 5G millimeter-wave antenna systems. A SrF 2 -based dielectric resonator antenna is designed and fabricated, which resonates at the desired 24.5 GHz and exhibits an outstanding S 11 of −43.95 dB and a broad bandwidth of 4.51 GHz.
研究领域:
材料科学
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电子工程
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高影响因子
危险品化学品经营许可证（带存储）