JOURNAL OF ELECTRONIC MATERIALS
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2022
·Vol. 51
·期 7
·3896-3902
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IF 2.047
Cheng Jiawen,Qing Zhenjun,Wang Jin,Zhao Yun,Zhou Xin,Zou Huapeng,Li Haiyan,Li Yingxiang
In this paper, the traditional solid-phase reaction sintering process was used to synthesize Ca 1-x Mg x V 2 O 6 (x = 0.03, 0.06, 0.09, 0.12) ceramics under low-temperature conditions. The effects of partial replacement of Ca 2+ by Mg 2+ on the A-site on the crystalline type, sintering temperature, microstructure, densification, and microwave dielectric performances of Ca 1-x Mg x V 2 O 6 ceramic were studied. The only crystalline phase of CaV 2 O 6 was observed in the ceramics. The sintering densification and dielectric performances of the Ca 1-x Mg x V 2 O 6 ceramic show a trend of first increasing and then decreasing with the increase of Mg 2+ content. The addition of Mg ions can effectively increase the Q × f value of the Ca 1-x Mg x V 2 O 6 ceramics but cannot improve the τ f value. The Ca 0.91 Mg 0.09 V 2 O 6 ceramic sintered at 725°C displayed good microwave dielectric performances: ε r = 10.41, Q × f = 68524 GHz, and τ f = − 36.8 ppm/°C. The good dielectric properties of this ceramic can meet the development needs of 5G communication technologies.
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
Crystals
·
2022
·Vol. 12
·期 11
·1608
·
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
✓ 已验证
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2022
·Vol. 33
·期 27
·21976-21984
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IF 2.779
Sha Ke,Lin Feng Li,Liu Bing,Song Kai Xin,Zhang Jia Heng
Dense (Sr 1 − x Ca x ) 2 (Ti 1 − x Sn x )O 4 ( x = 0.0, 0.05, 0.10, 0.15) ceramics were synthesized by a standard solid-state reaction method. The formation of solid-solution with an I 4/ mmm space group was revealed from the X-ray diffraction patterns and Rietveld refinement results. The variation of the microwave dielectric properties was systematically analyzed using the dielectric polarizability and complex chemical bond theory. The dielectric constant ( ε r ) was mainly determined by the ionic polarizability per unit volume. Qf value was closely associated with the increasing amount of Sr 3 Ti 2 O 7 secondary phase and the declined lattice energy. Meanwhile, the variation of Qf value was further analyzed by extrapolating the intrinsic dielectric loss from the infrared reflectivity spectra. τ f value was successfully adjusted toward zero, which could be explained by the enhanced bond energy. The optimal microwave dielectric properties were achieved at x = 0.10, with ε r = 33.6, Qf = 73,150 GHz, and τ f = 115 ppm/°C.
研究领域:
材料科学
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化学
✓ 已验证
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Xingyu Chen,Yeqing Guan,Zhaolin Zhong,Fenglin Wang,Wei Li,Haijun Mao,Zhuofeng Liu,Weijun Zhang
The effect of Zr 4+ substitution for Ti 4+ on the phase evolution and microwave dielectric properties of (Cu 1/3 Nb 2/3 ) 0.25 Ti 0.75- x Zr x O 2 (0 = x ≤ 0.35) ceramics prepared via conventional solid-state method has been investigated. With the increase of Zr substitution, the ceramics exhibit a gradual phase transition from a tetragonal rutile phase to an orthorhombic srilankite phase, where the synthesis of the srilankite phase at atmospheric pressure and temperature below 1200 °C in this study is reported for the first time. The crystal structure is tetragonal rutile type for the unsubstituted composition, orthorhombic srilankite type for the compositions with x > 0.30, and the compositions in between is a two-phase region with a mixture of rutile and srilankite. The Zr substitution has a great influence on the microstructure of the ceramics. In particular, for compositions where x > 0.1, the grain boundaries are surrounded by elongated powdery particles. The microwave dielectric properties of the ceramics are closely related to the phase transition process, in which Q × f is significantly improved and τ f decreases almost linearly with the increase of the content of srilankite phase. Optimum microwave dielectric properties with a permittivity of 35.1, a Q × f value of 7270 GHz, and a near-zero τ f of 9.0 ppm/°C are obtained in the ceramics with x = 0.3 sintered at 1150 °C for 4 h, which provides a new option for microwave devices requiring medium-permittivity dielectric ceramics .
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
Materials Today Communications
·
2023
·
IF 3.8
Zhuo Xing,Juhai Weng,Chi Ma
A series of Zn 2- x Cu x GeO 4 ceramics were prepared by the solid-phase sintering method. Cu 2+ substitution for Zn 2+ facilitated the single-phase formation and benefited densification via lowering the sintering temperatures , hence thereby the microwave dielectric properties were largely improved. A representative composition with x = 0.08 revealed a homogenous Zn 2 GeO 4 phase with good microwave dielectric properties: ε r ∼ 7.47, Q × f ∼ 56,980 GHz, and τ f ∼ −13.9 ppm/°C when sintered at 1000 °C. To evaluate the potential application of low-temperature cofired ceramics (LTCC), sintering aids (B 2 O 3 ) were added to the x = 0.08 sample to reduce its sintering temperature to below 960 °C. A dramatic improvement in Q × f ∼ 107,415 GHz was observed with only 0.5 wt % B 2 O 3 addition. Chemical compatibility was confirmed via cofiring with silver electrodes at 940 °C. All the merits show promising potential for advanced substrates.
研究领域:
材料科学
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电子材料
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Applied Ceramic Technology
·
2023
·Vol. 20
·期 6
·3786-3794
·
IF 2.1
Junqi Chen,Zhaohui Wang,Peili Qing,Jinwu Chen
A series of LiIn 1- x Al x O 2 ( x =0.05, 0.10, 0.15, 0.20, 0.25) microwave dielectric ceramics with low permittivity were synthesized via a solid-state reaction method. XRD, Raman spectra, and SEM analysis reveal that a single LiInO 2 tetragonal structure phase could be obtained at the x < 0.10, and with the x increased further to 0.15–0.25, the diffraction peaks of the secondary phase LiAlO 2 were detected. In the LiIn 1- x Al x O 2 ceramics, the τ f was closely related to the ε r , and the relative density, microstructure, and microwave dielectric properties were effectively improved by the Al 3+ substitution for In 3+ . Bond valence theory analysis demonstrates that the Al 3+ entered the In 3+ site exhibits a strength rattling effect, which is beneficial to the increase of ε r . While Al 3+ substitution for In 3+ simultaneously lowers the average ionic polarizability, resulting in a decrease in ε r . A near-zero τ f (0.74 ppm/°C) combined with ε r approximately 12.83, Q × f = 58 200 GHz, was obtained in LiIn0 .85 Al0 .15 O 2 ceramic sintered at 970°C.
研究领域:
材料科学
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物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 28
·1-11
·
IF 2.8
Xia Junjia,Ma Xing-Hua,Zhang Zhenlu,Nahm Sahn,Zhang Shuling,Ma Xingyi,Guo Feng
In this work, ZnGa 2– x O 4–1.5 x (0.0 ≤ x ≤ 0.15) ceramics were synthesized by a solid-state reaction method. ZnGa 2 O 4 ceramic that is sintered at 1300 °C/3 h exhibits good microwave dielectric properties with ε r of 11.06, Q × f of 74,730 GHz, and τ f of − 69.7 ppm/°C. However, it cannot be fully densified at temperatures lower than 960 °C, even when a large amount of B 2 O 3 is added, which seriously inhibits its application in the LTCC (low temperature cofired ceramic) field. Therefore, adding B 2 O 3 to Ga 2 O 3 -deficient ZnGa 2 O 4 ceramics is proposed to decrease the sintering temperature to below 960 °C. Owing to the dual effect of the B 2 O 3 -rich and ZnO-B 2 O 3 related liquid phases, ceramics with added B 2 O 3 (≥ 20 mol%) were found to sinter well at 950 °C, and good microwave dielectric properties were also achieved. In particular, 25 mol% B 2 O 3 added to ZnGa 1.95 O 3.925 ceramic sintered at 950 °C showed promising microwave dielectric properties for 5 G/6 G technologies without reaction with a silver electrode: ε r = 9.19, Q × f = 37,337 GHz, and τ f = − 58.3 ppm/°C.
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
Crystals
·
2023
·Vol. 13
·期 6
·955
·
IF 2.7
Qi Su,Jingjing Qu,Fei Liu,Changlai Yuan,Xiao Liu,Mingwei Su,Liufang Meng,Guohua Chen
Ti4+-ion-doped (n+ 1)SrO −nCeO2(n= 2) ceramic systems were prepared with the conventional solid-state reaction method, and the effects of the phase structures and compositions, sintering behaviors, microstructures and microwave dielectric properties of these ceramic systems were investigated in detail as a function of TiO2content. The analytical results of the XRD patterns show that the pure (n+ 1)SrO −nCeO2(n= 2) system is a composite-phase ceramic system with coexisting SrCeO3and Sr2CeO4phases (represented as a SrCeO3+ Sr2CeO4system), which belong to the orthogonal structures of the Pmcn (62) and Pbam (55) space groups, respectively. For thexTiO2-(1 − x) (SrCeO3+ Sr2CeO4) (x= 0.1–0.4) ceramic samples, the secondary phase Sr2TiO4can also be detected within the range of the investigated components. Meanwhile, the Raman spectroscopy, SEM-EDS, and HRTEM (SAED) analysis results also verified the correctness and consistency of the phase structures and compositions for all the given specimens. In addition, complex impedance spectroscopy was used to detect the conductive behavior of these compound ceramic systems, and the calculation results show that the appropriate addition of Ti4+-ions can make the SrCeO3+ Sr2CeO4system have better thermal stability. The composition ofx= 0.2 multiphase structural ceramic sample sintered at 1330 °C for 4 h has a near zero τfvalue of ~−4.6 ppm/°C, a moderateεrof ~40.3 and a higherQ×f~44,020 GHz (at 6.56 GHz). The relatively superior-performing ceramics developed in this work are expected to provide a promising microwave dielectric material for communication components.Keywords:phase structures and compositions;SrCeO3+ Sr2CeO4system;TiO2addition;microwave dielectric properties
研究领域:
材料科学
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陶瓷学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Min Yang,Yong Zheng,Weimin Ding,Xuepeng Lu,Lan Wang,Zhiyi Jiang,Bo Li,Zuowei Dong
This study addresses the challenge posed by the high sintering temperature (>850 °C) required for current high-performance BaZnP 2 O 7 -based ceramics by investigating the substitution of V 5+ at the P-site in BaZnP 2 O 7 ceramic. The objective was to lower the sintering temperature to below 850 °C while preserving the high-quality characteristics of the ceramics. Results reveal that the solubility of V 5+ in BaZnP 2 O 7 ceramics is limited, and secondary phases such as BaZn 2 (PO 4 ) 2 and Ba 3 V 2 O 3 (PO 4 ) 3 were formed when the concentration of V 5+ exceeds 0.005. The substitution of V 5+ for P 5+ effectively reduces the sintering temperature of BaZnP 2 O 7 ceramics from 840 (at x = 0) to 680 °C (at x = 0.10). The dielectric constant ( ε r ) of BaZn(P 1- x V x ) 2 O 7 ceramics is primarily influenced by porosity and the presence of secondary phases. The losses due to anharmonic vibrations in BaZn(P 1- x V x ) 2 O 7 ceramics were effectively reduced, leading to an increase in Q × f to ∼70,000 GHz at x = 0.005. The temperature coefficient of resonant frequency ( τ f ) is mainly affected by bond energy ( E ) and the content of the Ba 3 V 2 O 3 (PO 4 ) 3 phase. Ultimately, the BaZn(P 0.995 V 0.005 ) 2 O 7 ceramic sintered at 820 °C for 4 h exhibited the optimal microwave dielectric properties: ε r = 8.24, Q × f = 75,419 GHz, and τ f = −34.76 ppm/°C.
研究领域:
材料科学
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陶瓷工程
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2024
·Vol. 35
·期 21
·1-13
·
IF 2.8
Su Congxue,Tao Wenlong,Chen Lianchun,Che Haiyan,Wang Ruijuan,Fan Jun,Qin Xingliu,Chen Zhilin,Fang Liang
Orthorhombic olivine-structured LiTmRO 4 (R = Si, Ge) ceramics were synthesized using a solid-state reaction. Promising microwave dielectric properties of ε r = 8.18, τ f = 13.7 ppm/°C and a high-quality factor ( Q × f ) of 24,274 GHz for LiTmSiO 4 were obtained at 1130 °C, and ε r = 8.67, τ f = − 24.4 ppm/°C and Q × f = 19,231 GHz for LiTmGeO 4 were achieved at 1090 °C. According to the bond valence results, Tm 3+ and Ge 4+ presented a compressed state, but Li + exhibited a strong rattling state in LiTmGeO 4 , which led to a higher ε r than ε theo . The integrated effect of the rattling cations (Li + and Si 4+ ) and a compressed cation (Tm 3+ ) in LiTmSiO 4 resulted in a smaller positive deviation ∆ ε r . The larger packing fraction of LiTmSiO 4 contributed to a higher Q × f than that of LiTmGeO 4 . The R–O bond in both ceramics played a leading role in influencing Q × f according to the Phillips–Van Vechten–Levine chemical bond theory.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Jia Peng Yuan,Nuo Chen,Cheng Chao Hu,Bing Liu,Kai Xin Song
Cold sintering has proven effective in densifying microwave dielectric ceramics , but the resulting properties are significantly influenced by the crystallinity of the raw powder. In this study, lithium fluoride (LiF) raw powder underwent pre-calcination at temperatures ranging from 650 °C to 800 °C for 3 h to enhance grain crystallinity. The calcined powder was then mixed with 10 wt% deionized water and cold-sintered at 150 °C under 900 MPa for 1 h to achieve dense LiF ceramics. XRD results confirmed the preservation of LiF phase composition throughout both processes. Increasing calcination temperature exhibited a positive correlation with enhanced relative density in cold-sintered ceramics, reaching up to 98.6 % at 800 °C. SEM images revealed controlled grain growth with higher calcination temperatures. ε r increased with temperature, corresponding to the variation in relative density. Significantly, Qf value experienced substantial enhancement with increasing calcination temperature, ultimately achieving optimal microwave dielectric properties ( ε r = 8.80, Qf = 33,300 GHz, and τ f = −138 ppm/°C) through cold sintering of LiF powder pre-calcinated at 800 °C.
研究领域:
材料科学
·
陶瓷工程
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产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2024
·Vol. 107
·期 7
·4878-4890
·
IF 3.5
Qi Yuan,Yutong Meng,Tao Wang,Wencai Hu,Sen Wang,Gaobin Liu,Qiyao Wang,Kuoming Song,He Zhao,Shuai Yan,Xin Li
Li 2 (Mg 1– x Cu x ) 2 Mo 3 O 12 (0 ≤ x ≤0.1) ceramics were prepared using the conventional solid-phase method to study the effect of the Cu 2+ substitution for Mg 2+ on the sintering behavior, crystal structure, and microwave dielectric properties of ceramics. The experimental results show that the substitution of Cu 2+ for Mg 2+ reduces the sintering temperature of the ceramics to 550°C. X-ray diffraction patterns show that the introduction of Cu 2+ does not produce a new phase, but rather promotes the formation of Li 2 (Mg 1– x Cu x ) 2 Mo 3 O 12 solid solution. The microwave dielectric properties of the ceramics are influenced by the cell parameters, bond lengths, and structural stability. However, Cu 2+ creates oxygen vacancies during sintering, thereby deteriorating the dielectric properties ( Q × f decreases). The microwave dielectric properties of Li 2 (Mg 1– x Cu x ) 2 Mo 3 O 12 ceramics are optimal at a sintering temperature of 550°C and x = 0.02, with ε r = 9.17, Q × f = 7960 GHz, and τ f = –58.77 ppm/°C. Additionally, these ceramics are compatible with Al electrodes.
研究领域:
材料科学
·
晶体学
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DOI
高影响因子
危险品化学品经营许可证（带存储）