Microelectronics Packaging Application using post-LTCC technology

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000127-000129
Author(s):  
Yoshihiko IMANAKA ◽  
Hideyuki AMADA ◽  
Fumiaki KUMASAKA
Keyword(s):  
Dielectric Constant ◽  
Barium Titanate ◽  
Room Temperature ◽  
Electronic Devices ◽  
Tape Casting ◽  
Rapid Evolution ◽  
Lithium Ion ◽  
Aerosol Deposition ◽  
Nano Particles ◽  
Degree Of Crystallinity

The rapid evolution in electronic equipment has created a demand for advanced devices that are flexible, thin, and light in weight. This demand is driving the development of flexible and stretchable electronic devices as a core technology. To produce wearable computers, we need to fabricate functional membranes that contain passive devices such as capacitors and resistors on resin sheets at low temperatures. These sheets can then serve as mounting boards for various electronic devices. By improving the technique for room-temperature aerosol deposition (ASD) of a ceramic material (post-LTCC technology), we have established a technology for forming a dielectric inorganic film with an excellent degree of crystallinity and favorable electric properties for use in the production of flexible and stretchable electronic devices on a polyimide sheet. In the barium titanate film produced by the deposition on a polyimide sheet, a closely packed film with a high degree of sealing was formed by means of structure control to establish large-particle anchors, measuring about 100 nm in diameter, at the interface between the ceramic film and the polyimide sheet. The maximum dielectric constant of a film of barium titanate formed on the polyimide sheet by using the improved aerosol-deposition was 350 .By using this method to form a three-dimensional capillary structure inside a film, we produced a capacitor film with an apparent dielectric constant of 40,000 at room temperature. We also demonstrate cathode films for quick-charging lithium ion batteries. To achieve rapid charging, it is necessary to improve the speed of the chemical reaction between the cathode material and the electrolyte. Our process, however, does not require any unnecessary additive, such as a binder, unlike conventional tape casting method, and forms a film consisting of nano-particles of a high crystallinity, and is therefore effective for rapid charging.

scholarly journals Barium titanate flakes based composites for microwave absorbing applications

2013 ◽  
Vol 7 (4) ◽  
pp. 189-193 ◽  
Author(s):  
Raj Jain ◽  
Ashish Dubey ◽  
Amit Soni ◽  
Sanjiv Gupta ◽  
Trilok Shami
Keyword(s):  
Barium Titanate ◽  
Reflection Loss ◽  
Composite Laminates ◽  
Sol Gel ◽  
Tape Casting ◽  
Weight Ratio ◽  
Single Layer ◽  
Wide Frequency Range ◽  
Nano Particles ◽  
Electromagnetic Properties

Barium titanate (BT) has attained research focus in recent past owing to considering its high dielectric constant and stealth capabilities in microwave region. Shape effects of BT viz. powder, micron size flakes, nano particles and nanotubes have been studied vastly for its stealth capabilities. Present study aims at the preparation of millimetric size barium titanate flakes (BTFs) via controlled sol-gel process followed by tape casting. BTFs were mixed in varied weight ratio (50-90 wt.%) with polyurethane resin to fabricate composite laminates. Electromagnetic properties measurement in X and Ku band revealed high values of real and imaginary permittivity. Reflection loss measurements demonstrated more than 20 dB loss in wide frequency range (11.4-13.6 GHz). For single layer microwave absorber, reflection loss values have been calculated and it is observed that calculated and measured reflection loss values are in good agreement to each other. Developed material can find applications in broadband radar signature reduction.

Dielectric Constant of Barium Titanate Synthesized by Containerless Processing

2004 ◽  
Vol 848 ◽  
Author(s):  
Jianding Yu ◽  
Paul-François Paradis ◽  
Takehiko Ishikawa ◽  
Shinichi Yoda
Keyword(s):  
Dielectric Constant ◽  
Barium Titanate ◽  
Single Crystal ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Undercooled Liquid ◽  
Electrostatic Levitation ◽  
Containerless Processing ◽  
Synthesis Technique ◽  
Loss Component

ABSTRACTContainerless processing is an attractive synthesis technique that permits deep undercooling and provides the possibility to solidify the undercooled liquid into a selected phase, and to synthesize materials with novel properties. Spheroidal BaTiO3 samples with a diameter of approximately 2mm were solidified by containerless processing, using an electrostatic levitation apparatus. Single crystal hexagonal BaTiO3 and polycrystalline perovskite BaTiO3 were successfully synthesized at different undercoolings levels. An oxygen-deficient single crystal of hexagonal BaTiO3 obtained with this method, exhibited a giant permittivity higher than 100000, with a loss component tanδ of about 0.1 at room temperature. The permittivity showed weak temperature dependence in the 70 K to 300 K range, and a dramatic drop by 2 orders of magnitude below 70 K. In comparison, the polycrystalline perovskite BaTiO3 showed a permittivity of 4000 at room temperature.

Preparation of Potassium Niobate-Coated Barium Titanate Accumulation Ceramics by Solvothermal Synthesis and Enhancement of Piezoelectric Property

2013 ◽  
Vol 566 ◽  
pp. 76-80 ◽  
Author(s):  
Kenta Yamashita ◽  
Shigehito Shimizu ◽  
Nobuhiro Kumada ◽  
Kouichi Nakashima ◽  
Ichiro Fujii ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Barium Titanate ◽  
Piezoelectric Property ◽  
Solvothermal Synthesis ◽  
Room Temperature ◽  
Piezoelectric Properties ◽  
Solvothermal Method ◽  
Potassium Niobate ◽  
Nanostructured Ceramics ◽  
Dielectric And Piezoelectric Properties

Barium titanate (BaTiO3, BT) - potassium niobate (KNbO3, KN) nanostructured ceramics with artificial morphotropic phase boundary (MPB) structure were successfully prepared at temperatures below 230 °C by solvothermal method. Various characterizations suggested that the BT-KN nanostructured ceramics exhibited a porosity of around 30 % and heteroepitaxial interface between BT and KN. Their dielectric and piezoelectric properties were measured at room temperature, and the dielectric constant and apparent piezoelectric constant estimated from slope of strain and electric field curve was 370 and 136 pm/V, respectively.

Preparation of Ferroelectric BaTiO3 Films by Electrophoretic Deposition Technique

2007 ◽  
Vol 336-338 ◽  
pp. 87-90
Author(s):  
Ya Lu Ma ◽  
Yu Zhang ◽  
Hong Long Zhu
Keyword(s):  
Dielectric Constant ◽  
Barium Titanate ◽  
Electrophoretic Deposition ◽  
Room Temperature ◽  
Annealing Temperature ◽  
Ferroelectric Films ◽  
Final Annealing ◽  
Xrd Pattern ◽  
Uniform Microstructure ◽  
Room Temperature Dielectric Constant

Barium titanate ferroelectric films on Pt substrates were fabricated by electrophoretic deposition (EPD) technique. The barium titanate films sintered at different temperature (600°C, 900°C, 1050°C, 1150°C, 1200°C) for 2h, which were prepared via repeated EPD-sintering route 2~3 times were sufficiently dense and had uniform microstructure. The XRD pattern and SEM microphotography have been measured in order to investigate the effects of the final annealing temperature on the phase compositions and microstructure of the film. The experiment results showed that barium titanate films were crystallized into the tetragonal phase at 1050°C and above. The room temperature dielectric constant (ε) and loss tangent (tanδ) at 1kHz were respectively determined for different samples sintered at 600°C, 900°C, 1050°C, 1150°C and 1200°C. Both ε and tanδ showed anomaly peaks at 125°C. The results showed that typical BaTiO3 films sintered at 1050°C having higher dielectric constant (ε=2300) and lower dielectric loss (tanδ=0.02). The room temperature remanant polarization (Pr) and coercive field (EC) were found to be 1.9μC/cm2 and 35kV/cm, respectively.

High-Performance Lead-Free Barium Titanate Piezoelectric Ceramics

2008 ◽  
Vol 54 ◽  
pp. 7-12 ◽  
Author(s):  
Tomoaki Karaki ◽  
Masatoshi Adachi ◽  
Kang Yan
Keyword(s):  
Phase Transition ◽  
Dielectric Constant ◽  
Transition Temperature ◽  
Barium Titanate ◽  
Phase Transition Temperature ◽  
Room Temperature ◽  
Electromechanical Coupling ◽  
Electromechanical Coupling Factor ◽  
Coupling Factor ◽  
Piezoelectric Constants

Barium titanate (BaTiO3) ceramics with a high-density were fabricated by two-step sintering method from hydrothermally synthesized 100 nm BaTiO3 nano-particles. The best specimen with an average grain size of 1.6 μm and a density of 5.91 g/cm3 (98.3% of the theoretical value). The dielectric constant was 4500 and electromechanical coupling factor kp was 45%. Large piezoelectric constants d33 = 460 pC/N and d31 = -185 pC/N were observed in the specimens. This was an important practical result towards obtaining a high d33 in non-lead-based BaTiO3 ceramics manufactured by a low-cost process. These results also indicated the possibility of using BaTiO3 ceramics in piezoelectric devices at room temperature. Temperature dependence of dielectric constant showed two peaks located at 24 and 126 oC, corresponding to orthorhombic-to-tetragonal phase transition temperature Tot and Curie temperature Tc, respectively. Owing to the size effect of nanocrystals, Tot shifted to 24 oC. The maximum of electromechanical coupling factor kp appeared close to the phase transition temperature. It also caused a very large temperature coefficient of resonance frequency from room temperature to 60 oC. Hysteresis curve measurement showed a very low coercive field Ec = 115 V/mm. A large Poisson’s ratio, about 0.38, was determined from the ratio of overtone frequency and resonant frequency in the planar mode. The high Poisson’s ratio and the large dielectric constants are most likely the origin of the high piezoelectric constants in the ceramics.

Room-Temperature Fabrication of Flexible Thin-Film Lithium Batteries Based on Solid Electrolytes and Polyimide Substrates

2015 ◽  
Vol 723 ◽  
pp. 664-669 ◽  
Author(s):  
Mu Chen ◽  
Yue Yan ◽  
Wei Ming Liu ◽  
Chen Zhou ◽  
Zhi Qiang Guo ◽  
...  
Keyword(s):  
Thin Film ◽  
Lithium Batteries ◽  
Room Temperature ◽  
Electronic Devices ◽  
Lithium Ion ◽  
Ceramic Substrates ◽  
Active Layers ◽  
Thin Polymer ◽  
Lithium Ion Conductivity ◽  
Redox Centers

Flexible thin-film lithium batteries can power flexible electronic devices and wearable devices. Here we report room-temperature fabrication of flexible batteries with Li/LiPON/LiFe (WO4)2 active layers on polyimide substrates by sequential magnetron sputtering and thermal evaporation. Inorganic solid electrolyte LiPON films were well prepared to achieve lithium ion conductivity of 1.794×10-6 S/cm in the composition of Li2.7P(O0.99N0.11)4. Due to two redox centers of Fe3+ and W6+ in amorphous LiFe (WO4)2 cathode films, large initial specific capacities of 115.5 μAh/(cm2-μm) and 65.4 μAh/(cm2-μm) are achieved in the flat and bending batteries respectively. After 200 cycles, the discharge capacity remains 27.6 μAh/(cm2-μm). Low-temperature fabrication process of flexible batteries insures the use of lightweight and thin polymer substrates instead of high temperature resistant metal and ceramic substrates.

Effect of Sintering Time on Dielectric Properties of Barium Titanate and Nb Doped Barium Titanate

2016 ◽  
Vol 860 ◽  
pp. 129-133 ◽  
Author(s):  
M.K. Rahman ◽  
M.F. Hossain ◽  
Kazi Mohammad Shorowordi ◽  
M.A. Matin
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Barium Titanate ◽  
Room Temperature ◽  
Niobium Oxide ◽  
Dielectric Material ◽  
Multilayer Ceramic Capacitors ◽  
Sintering Time ◽  
High K ◽  
Room Temperature Dielectric Constant

Barium titanate (BaTiO3) with its perovskite structure is a promising dielectric material for many applications such as transducers, actuators, high-k dielectrics and multilayer ceramic capacitors (MLCC). In this study, we have investigated the effect of sintering time on dielectric properties of BaTiO3 and Nb-doped BaTiO3. BaTiO3 was doped with 0.3 mol % niobium oxide (Nb2O5). At first, nanosized pure BaTiO3 and Nb2O5 doped BaTiO3 were milled, dried and pressed into pellets to prepare green samples. Then, the samples were sintered at 1275°C for different time periods ranging from 2 to 5 hrs. Single stage sintering was adopted for the densification of prepared samples. Microstructure of the sintered samples was investigated employing Field-emission scanning electron microscope (FESEM). Dielectric properties of the samples were measured using an impedance analyzer. Finally, a correlation was established between the dielectric properties of the sintered samples and their microstructure. Nb has shown to provide strong inhibiting effect after sintering the samples in the range of 2 to 5 hours at 1275°C thereby, resulted in higher dielectric properties of doped BaTiO3 ceramics compared to that of pure BaTiO3. The best room temperature dielectric constant of 7200 was obtained for Nb doped BaTiO3 sintered at 1275°C for five hours. Such improved dielectric constant is attributed to the optimum grain size of about 1 micron at this sintering temperature.

Green synthesis of mixed metallic nanoparticles using room temperature self-assembly

2017 ◽  
Vol 13 (2) ◽  
pp. 4671-4677 ◽  
Author(s):  
A. M. Abdelghany ◽  
A.H. Oraby ◽  
Awatif A Hindi ◽  
Doaa M El-Nagar ◽  
Fathia S Alhakami
Keyword(s):  
Self Assembly ◽  
Metallic Nanoparticles ◽  
Room Temperature ◽  
Bimetallic Nanoparticles ◽  
Reduction Process ◽  
Nano Particles ◽  
Nano Structure ◽  
Small Shift ◽  
Molar Ratios ◽  
Vis Spectroscopy

Bimetallic nanoparticles of silver (Ag) and gold (Au) were synthesized at room temperature using Curcumin. Reduction process of silver and gold ions with different molar ratios leads to production of different nanostructures including alloys and core-shells. Produced nanoparticles were characterized simultaneously with FTIR, UV/vis. spectroscopy, transmission electron microscopy (TEM), and Energy-dispersive X-ray (EDAX). UV/vis. optical absorption spectra of as synthesized nanoparticles reveals presence of surface palsmon resonance (SPR) of both silver at (425 nm) and gold at (540 nm) with small shift and broadness of gold band after mixing with resucing and capping agent in natural extract which suggest presence of bimetallic nano structure (Au/Ag). FTIR and EDAX data approve the presence of bimetallic nano structure combined with curcumin extract. TEM micrographs shows that silver and gold can be synthesized separately in the form of nano particles using curcumin extract. Synthesis of gold nano particles in presence of silver effectively enhance and control formation of bi-metallic structure.

Atomistic prediction on the configuration- and temperature-dependent dielectric constant of Be0.25Mg0.75O superlattice as a high-κ dielectric layer

2021 ◽  
Author(s):  
Gyuseung Han ◽  
In Won Yeu ◽  
Kun Hee Ye ◽  
Seung-Cheol Lee ◽  
Cheol Seong Hwang ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dft Calculations ◽  
Bond Length ◽  
Dielectric Layer ◽  
Room Temperature ◽  
High Dielectric Constant ◽  
Temperature Dependent ◽  
High Dielectric

Through DFT calculations, a Be0.25Mg0.75O superlattice having long apical Be–O bond length is proposed to have a high bandgap (>7.3 eV) and high dielectric constant (∼18) at room temperature and above.

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