JOURNAL OF ELECTRONIC MATERIALS
·
2017
·Vol. 46
·期 10
·5877-5883
·
IF 1.579
Wang Yan,Han Jing,Guo Fu,Ke Xiaoxing
Grain orientations are a significant factor under high-density current stressing, but there are few literature reports about the influence of grain orientation on electromigration in composite solder joints. Most research relating to the electromigration behavior of composite solders have been carried out by adding different kinds of reinforced particles in order to relieve the electromigration phenomena, while the impacts of grain orientation on the electromigration have been neglected. In this paper, Sn-3.5Ag composite solder joints reinforced by 2 vol.% Cu were fabricated to investigate the effects of Sn grain orientation on electromigration. The one-dimensional single-grained solder joints were stressed under a constant current density of 10 4 A/cm 2 for different times at room temperature. The samples, of which the c -axis of the Sn grains was nearly parallel to the electron flow direction, exhibited serious electromigration-induced phenomena after current stressing for 528 h. However, electromigration was not observed in the samples where the Sn grains had their c -axis perpendicular to the electron flow direction. Therefore, the grain orientations have a great influence on the electromigration behavior in composite solders and Cu atoms moved faster along the c -axis of the Sn grains than along the a - and b -axes during current stressing.
研究领域:
材料科学
·
电子封装技术
·
金属材料学
·
微电子可靠性
·
物理冶金
✓ 已验证
DOI
高影响因子
THIN SOLID FILMS
·
2024
·
IF 2
Silin Han,Chongyang Li,Yuhang Chen,Yunwen Wu,Ming Li,Tao Hang
In this paper, the changes in microstructure and conductivity of the films before and after thermal and laser annealing are observed, which corresponds to various combinations of crystallite sizes and impurity densities. The results show that the impurities promote grain boundary migration at larger initial crystallite sizes, which contradicts previous reports. This is because the rate of grain growth is determined by the driving force and resistance to grain growth, the former provided by the energy of grain boundaries and the impurities outside the nanograin boundaries, and the latter by the impurities enriched within the boundaries. Additionally, laser annealing is more effective than thermal annealing in stimulating impurity diffusion, resulting in a reduced influence of impurities on grain growth.
研究领域:
材料科学
·
冶金学
·
薄膜技术
·
固体物理
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yingchun Liu,Hongjun Zhang,Chengyu Ma,Kai Li,Bin Yang,Wenwu Cao,Jiubin Tan
Textured BaTiO 3 -based piezoelectric ceramics show the excellent application potential as their piezoelectric characteristics almost approach the commercial lead-based ceramics. Piezoelectric multilayer actuators (MLAs) with low driving voltages and compact structures are great in line with the equipment trend of miniaturization and functional integration. However, the coarse textured grains result in few grain layers in each thin ceramic layer of MLAs, hardly guaranteeing the electromechanical dependability. In this work, we combined the composition regulation with a modified template grain growth (TGG) to prepare fine-grained textured ceramics. The Zr 4+ and Sn 4+ co-substituted (Ba 0.95 Ca 0.05 )(Ti 0.94 Zr 0.05 Sn 0.01 )O 3 (BCZTS) was chosen as the matrix composition. Unreacted BaCO 3 (BC, 7.3 % in content) was artificially introduced into matrix to realize the partial reaction template grain growth (RTGG), reducing textured grains from 9.7 μm to 6.9 μm. Textured BCTZS-BC MLAs achieved high texture degree of 92 % and further smaller grain size of 3.4 μm at 1300 °C, due to inhibition on mass transfer and improvement on thermal conductivity of Pt electrodes. The high strain of 0.12 % in textured MLAs is almost 2.3 times enhancement compared to non-textured counterparts, and the ultralow strain hysteresis H s of 5.6 % at 30 kV/cm is equivalent to that in PZT MLAs. The microscopic coercive voltage is 3.1 V with a maximum displacement of 210 p.m., which is mainly ascribed to the smaller domain sizes and the favorable “4O” domain configuration in textured MLAs.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
ULTRASONICS SONOCHEMISTRY
·
2024
·
IF 8.7
Xiaoqiang Zhang,Hongyue Chen,Yuhan Wang,Xin Gao,Zhijun Wang,Nan Wang,Duyang Zang
We investigate the effect of ultrasound on the evaporation and crystallization of sessile NaCl solution droplets which were positioned in traveling or standing wave ultrasound field. The experimental results indicated that the ultrasound field can significantly accelerate the evaporation rate of the sessile droplets and refine the crystal grains. By adjusting the distance between the sessile droplets and the ultrasound emitter, it is found that, in traveling wave ultrasound field, the sessile droplet evaporation time and the time for the appearance of NaCl grains exhibited a fluctuating increase as the droplet-emitter distance increased. While in the standing wave ultrasound, the sessile droplet evaporation rate increases with the increasing droplet-emitter distance. Overall, the traveling wave ultrasound field has a stronger effect on grain refinement of the sessile droplets than the standing wave ultrasound field. The grain refinement is attributed to the decrease of critical nucleation radius caused by ultrasound energy and the increase of the nucleation rate caused by the accelerated evaporation rate. In addition, the breakage of grains caused by ultrasonic cavitation would also lead to grain refinement.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Ruxia Liu,Chuandong Wu,Jian Zhang,Guoqiang Luo,Qiang Shen,Lianmeng Zhang
We report on an investigation of the influence of sintering temperature on microstructure and mechanical behaviors of the Al matrix composites. In this paper, the ultrafine grained AA7075/B 4 C composites was synthesized via cryomilling and one-step consolidation. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were utilized for characterization of the grain size of the AA7075/B 4 C composites consolidated at various sintering temperatures. Our results indicated that the grain size increased gradually from ∼73.1 nm to ∼184.7 nm with the sintering temperature increasing from 350 °C to 450 °C. The formation of abnormal grain growth was observed in the AA7075/B 4 C composite consolidated at 500 °C B 4 C particles distributed homogenously, discretely and randomly in the Al matrix based on the observation in Field-emission scanning electron microscopy (FESEM). The porosities were found to decrease in the AA7075/B 4 C composites with the rising of sintering temperature. The Vickers hardness , compressive yield strength and fracture strength of the AA7075/B 4 C consolidated at 450 °C were 233 HV, 724.9 MPa and 834.5 MPa, respectively. The analysis of strengthening mechanisms revealed that increasing of sintering temperature resulted in the sacrifice of grain-boundary strengthening and dislocation strengthening.
研究领域:
材料科学
·
金属基复合材料
·
粉末冶金
·
显微结构表征
·
力学行为
·
材料加工工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Yan Ziyang,Wu Angxuan,Wang Xilin,Huang Rongxia,Yan Nianping,Jia Zhidong,Wang Liming
In this paper, ZnO was used as a sintering aid as well as reactant in the reactive flash sintering (RFS) of zinc-containing ceramic materials at room temperature (25 °C). The RFS of ZnO-based ceramics, both ZnAl 2 O 4 and Zn 2 TiO 4 , were achieved with the application of a high electric field. Contrary to previous reports, the RFS of ZnAl 2 O 4 was divided into two stages according to temperature changes, and the effect of the reaction exotherm on the RFS was presented for the first time in this paper. In addition, the RFS produced a larger grain size of ZnAl 2 O 4 than conventional sintering did.
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Haibin Sun,Xue Guo,Jiao Li,Guochang Li,Zanzhong Yang,Hao Ding,Weilu Yan,Shuai Qi,Peng Wang,Youjie Song
In order to clarify the effect of grain size on the electrical performance of BaZr 0.1 Ce 0.7 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) solid electrolytes with addition of NiO, microcrystalline (~1.5 µm) and ultrafine-grained (~280 nm) BZCYYb electrolytes (with 1 wt% NiO) were fabricated by the conventional and two-step sintering method, respectively. The results show that compared with microcrystalline electrolytes, the ultrafine-grained electrolytes have similar grain-interior conductivities, but much lower grain-boundary conductivities, illustrating that the grain boundary is not conducive for ionic transport. As a result, the electrical conductivity of microcrystalline electrolytes (1.9 × 10 −2 S cm −1 at 600 °C in wet air) is higher than that of ultrafine-grained electrolytes (1.1 × 10 −2 S cm −1 at 600 °C in wet air). In addition, the OCV (open-circuit voltage) values of electrolyte-supported single cells show that the undesired electronic conduction exists in the electrolytes due to the BaY 2 NiO 5 impurity formed by the reaction of NiO and BZCYYb. The ultrafine-grained electrolytes show lower OCV values than that of microcrystalline ones, due to the prolonged electronic transport paths. Therefore, large-grained or grain boundary-free microstructure are necessary for improving the electrical performance of BZCYYb electrolytes.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Q.B. Chen,B. Meng,M.Y. Zhao,H. Xie,L.F. Bian,X. Yang
In order to investigate the grain size effect on the electrical conductivity of the submicron samarium-heavily-doped ceria , the Ce 0.8 Sm 0.2 O 1.9 (SDC20) ceramics with grain sizes from 128 nm to 533 nm were prepared by sintering at 1000–1300 °C in the air atmosphere. The crystalline structure, micro-morphology, density and electrical conductivity of the SDC20 ceramics were measured and characterized by XRD , SEM, TEM, Archimedes method and electrochemical impedance spectrum, respectively. All the sintered samples show the single SDC phase, low porosity and clean grain boundary without any impurities. The grain sizes of SDC ceramics grow continuously with the rising sintering temperature , and the relative densities increase as the sintering temperature rises from 1000 °C to 1200 °C and then decrease with the temperature from 1200 °C to 1300 °C. The specific grain boundary conductivity of SDC keeps decreasing while the grain and apparent grain boundary conductivities increase during the whole grain size range of 128–533 nm.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2025
·
IF 6.3
Mengzhu Li,Yanqing Wang,Zhiping Fang,Dongchen Guo,Min Fan,Hui Dai,Fuling Guo,Wangchao Chen,Chengwu Shi,Peng Cui
Antimony selenosulfide (Sb 2 (S,Se) 3 ) demonstrates strong potential for thin-film solar cells owing to its tunable bandgap, low toxicity, and high stability. However, conventional fabrication methods often yield films with small grain sizes and random orientations, which hinder device performance. Herein, an in situ polymerization-assisted grain growth (iPAGG) strategy was developed, specifically enabling the oriented growth of Sb 2 (S,Se) 3 on Cd-free TiO 2 substrates, by introducing acrylic acid (AA) into the chemical bath deposition process. The carboxylate groups from AA coordinate with Sb 3+ ions, promoting oriented growth of Sb 2 (S,Se) 3 film. This approach yields films with enlarged grains, reduced defect densities, and strengthened [ hk 1] preferred orientation. As a result, Cd-free Sb 2 (S,Se) 3 solar cells employing the optimized AA concentration yielded a champion power conversion efficiency (PCE) of 7.24%, outperforming the control device (6.70%). Further interfacial modification with poly (acrylic acid)-modified SnO 2 boosts the PCE to 7.55%. This work offers an effective way toward the fabrication of high-performance and environmentally friendly Sb 2 (S,Se) 3 photovoltaics.
研究领域:
材料科学
·
光伏技术
·
纳米结构制备
·
表面化学
·
半导体物理
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 18
·2309019
·
IF 27.4
Zhanhui Jia,Hao Shen,Jiawei Kou,Tianyi Zhang,Zhen Wang,Wei Tang,Marca Doeff,Ching-Yu Chiang,Kai Chen
The application of solid-state electrolytes in Li batteries is hampered by the occurrence of Li-dendrite-caused short circuits. To avoid cell failure, the electrolytes can only be stressed with rather low current densities, severely restricting their performance. As grain size and pore distributions significantly affect dendrite growth in ceramic electrolytes such as Li 7 La 3 Zr 2 O 12 and its variants; here, a “detour and buffer” strategy to bring the superiority of both coarse and fine grains into play, is proposed. To validate the mechanism, a coarse/fine bimodal grain microstructure is obtained by seeding unpulverized large particles in the green body. The rearrangement of coarse grains and fine pores is fine-tuned by changing the ratio of pulverized and unpulverized powders. The optimized bimodal microstructure, obtained when the two powders are equally mixed, allows, without extra interface decoration, cycling for over 2000 h as the current density is increased from 1.0 mA·cm −2 , and gradually, up to 2.0 mA·cm −2 . The “detour and buffer” effects are confirmed from postmortem analysis. The complex grain boundaries formed by fine grains discourage the direct infiltration of Li. Simultaneously, the coarse grains further increase the tortuosity of the Li path. This study sheds light on the microstructure optimization for the polycrystalline solid-state electrolytes.
研究领域:
材料科学
·
储能技术
·
固态电池
·
陶瓷电解质
·
微观结构工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2017
·
IF 2.299
Misganaw Alemu Zeleke,Dong-Hau Kuo,Osman Ahmed Zelekew,Albert Daniel Saragih
Ge-substituted Cu 2 Sn(S,Se) 3 bulks with Cu 2 (Sn 1- x Ge x )(S,Se) 3 formula at x = 0, 0.25, 0.50, 0.75, and 1.0 were synthesized by reactive liquid phase sintering , where the heating process was held at 200 °C for 20 min before reaching the sintering temperature of 600 °C for 30 min. In the presence of volatile Sb 2 S 3 sintering aid , the effects on densification , grain boundary, crystalline size, and electrical properties of Ge-substitution were investigated. Cu 2 (Sn 1- x Ge x )(S,Se) 3 showed p-type behavior for all x values. It was found that the mobility was increased sharply and carrier concentration was decreased rapidly as the x -value was increased. The electrical conductivities were found to be 14.0, 22.7, 36.8, 126, and 153 S/cm at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. X-ray diffraction (XRD) peaks were shifted to the higher angle and band gaps increased upon successive increasing of the Ge/[Ge+Sn] fraction being 1.19, 1.21, 1.22, 1.24, and 1.26 eV at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. The studies of Ge-x-CTSSe bulks were based on Ge Sn defects and supported by the data of morphological, structural, electrical, and optical properties .
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
Coatings
·
2022
·Vol. 12
·期 4
·526
·
IF 3.236
Jiaqi Li,Junjun Wang,Fengmin Wu,Hui Ma,Tianyi Ma,Yu Tian,Danqing Liu,Bin Yang
In this paper, Bi2O3-doped (K0.5Na0.5)NbO3(x = 0.1, 0.2, 0.3, 0.4) lead-free ceramics are prepared by a conventional solid-state reaction and analyzed by studying the structure, ferroelectric, and piezoelectric properties. It is found that the doping of Bi2O3increases the proportion of the trigonal phase in KNN ceramics, thus enabling the construction of KNN ceramics with an orthogonal–trigonal phase boundary at room temperature. At the same time, doping with Bi2O3can reduce the grain size and improve grain size uniformity of the ceramics. The KNN-0.1%Bi2O3ceramic has the best piezoelectric properties in all composition; the results are as follows:d33= 121pC/N,kp= 0.474,kt= 0.306.Keywords:KNN lead-free ceramics;Bi2O3doping;grain effects;piezoelectric property
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）